10-Q

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

WASHINGTON, D.C. 20549

___________________________________________

FORM 10-Q

___________________________________________

(Mark One)
☒	QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934

For the quarterly period ended March 31, 2021

or

☐ TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934

For the transition period from ________ to ________             

Commission file number: 001-34962

ZOGENIX, INC.

(Exact Name of Registrant as Specified in its Charter)

Delaware	20-5300780
(State or Other Jurisdiction of Incorporation or Organization)	(I.R.S. Employer Identification No.)
5959 Horton Street, Suite 500 Emeryville, California 94608
(Address of Principal Executive Offices and Zip Code)

510-550-8300

(Registrant’s Telephone Number, Including Area Code)

Securities registered pursuant to Section 12(b) of the Act:

Title of each class	Trading Symbol	Name of each exchange on which registered
Common Stock, par value $0.001 per share	ZGNX	The Nasdaq Global Market

Indicate by check mark whether the registrant: (1) has filed all reports required to be filed by Section 13 or 15(d) of the Securities Exchange Act of 1934 during the preceding 12 months (or for such shorter period that the registrant was required to file such reports), and (2) has been subject to such filing requirements for the past 90 days.    ☒  Yes   ☐  No

Indicate by check mark whether the registrant has submitted electronically every Interactive Data File required to be submitted pursuant to Rule 405 of Regulation S-T (§232.405 of this chapter) during the preceding 12 months (or for such shorter period that the registrant was required to submit such files).    Yes  ☒    No  ☐

Indicate by check mark whether the registrant is a large accelerated filer, an accelerated filer, a non-accelerated filer, a smaller reporting company, or an emerging growth company. See the definitions of “large accelerated filer,” “accelerated filer,” “smaller reporting company,” and “emerging growth company” in Rule 12b-2 of the Exchange Act.

Large accelerated filer	☒	Accelerated filer	☐
Non-accelerated filer	☐	Smaller reporting company	☐
		Emerging growth company	☐

If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act. ☐

Indicate by check mark whether the registrant is a shell company (as defined in Rule 12b-2 of the Exchange Act).    ☐  Yes    ☒  No

The number of outstanding shares of the registrant’s common stock, par value $0.001 per share, as of April 30, 2021 was 55,812,590.

ZOGENIX, INC.

FORM 10-Q

FOR THE QUARTERLY PERIOD ENDED MARCH 31, 2021

TABLE OF CONTENTS

 

		Page
	PART I. FINANCIAL INFORMATION
Item 1.	Financial Statements
	Condensed Consolidated Balance Sheets as of March 31, 2021 and December 31, 2020 (unaudited)	1
	Condensed Consolidated Statements of Operations for the Three Months Ended March 31, 2021 and 2020 (unaudited)	2
	Condensed Consolidated Statements of Comprehensive Loss for the Three Months Ended March 31, 2021 and 2020 (unaudited)	3
	Condensed Consolidated Statements of Stockholders’ Equity for the Three Months Ended March 31, 2021 and 2020 (unaudited)	4
	Condensed Consolidated Statements of Cash Flows for the Three Months Ended March 31, 2021 and 2020 (unaudited)	5
	Notes to the Condensed Consolidated Financial Statements (unaudited)	6
Item 2.	Management’s Discussion and Analysis of Financial Condition and Results of Operations	19
Item 3.	Quantitative and Qualitative Disclosures about Market Risk	29
Item 4.	Controls and Procedures	29
	PART II. OTHER INFORMATION
Item 1.	Legal Proceedings	30
Item 1A.	Risk Factors	30
Item 2.	Unregistered Sales of Equity Securities and Use of Proceeds	30
Item 3.	Defaults Upon Senior Securities	30
Item 4.	Mine Safety Disclosures	30
Item 5.	Other Information	30
Item 6.	Exhibits	31
	Signatures	32

PART I. FINANCIAL INFORMATION

Item 1. Financial Statements

ZOGENIX, INC.

CONDENSED CONSOLIDATED BALANCE SHEETS (Unaudited)

(In thousands, except par value)

	March 31, 2021		December 31, 2020
ASSETS
Current assets:
Cash and cash equivalents	$	86,317	$	166,916
Marketable securities	348,905		338,193
Accounts receivable, net	6,119		3,824
Inventory	2,324		1,026
Prepaid expenses and other current assets	11,065		12,215
Total current assets	454,730		522,174
Property and equipment, net	8,377		8,724
Operating lease right-of-use assets	7,452		7,748
Intangible asset, net	96,587		98,558
Goodwill	6,234		6,234
Other non-current assets	7,584		7,692
Total assets	$	580,964	$	651,130
LIABILITIES AND STOCKHOLDERS’ EQUITY
Current liabilities:
Accounts payable	$	11,964	$	11,945
Accrued and other current liabilities	30,749		54,964
Deferred revenue, current	5,297		5,318
Current portion of operating lease liabilities	1,621		1,688
Current portion of contingent consideration	8,900		8,800
Total current liabilities	58,531		82,715
Deferred revenue, noncurrent	5,664		5,479
Operating lease liabilities, net of current portion	9,937		10,314
Contingent consideration, net of current portion	34,100		33,600
Convertible senior notes	151,451		149,353
Total liabilities	259,683		281,461
Commitments and contingencies
Stockholders’ equity:
Preferred stock, $0.001 par value; 10,000 shares authorized; none issued and outstanding	—		—
Common stock and additional paid-in capital, $0.001 par value: 100,000 shares authorized; 55,813 and 55,736 shares issued and outstanding at March 31, 2021 and December 31, 2020, respectively	1,701,788		1,694,580
Accumulated deficit	(1,380,470)		(1,324,840)
Accumulated other comprehensive loss	(37)		(71)
Total stockholders’ equity	321,281		369,669
Total liabilities and stockholders’ equity	$	580,964	$	651,130

See accompanying notes to the unaudited condensed consolidated financial statements.

ZOGENIX, INC. | Q1 2021 Form 10-Q | 1

ZOGENIX, INC.

CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS (Unaudited)

(In thousands, except per share amounts)

	Three Months Ended March 31,
	2021		2020
Revenues:
Net product sales	$	12,349	$	—
Collaboration revenue	1,335		1,249
Total revenues	13,684		1,249
Costs and expenses:
Cost of product sales (excluding amortization of intangible asset)	676		—
Research and development	30,969		33,240
Selling, general and administrative	31,272		21,318
Intangible asset amortization	1,971		—
Acquired in-process research and development costs	—		1,500
Change in fair value of contingent consideration	600		(7,900)
Total costs and expenses	65,488		48,158
Loss from operations	(51,804)		(46,909)
Interest income	308		1,088
Interest expense	(3,737)		—
Other (expense) income, net	(397)		20,021
Net loss	$	(55,630)	$	(25,800)
Net loss per share, basic and diluted	$	(1.00)	$	(0.54)
Weighted average number of shares used in the calculation of basic and diluted net loss per common share	55,750		48,185

See accompanying notes to the unaudited condensed consolidated financial statements.

ZOGENIX, INC. | Q1 2021 Form 10-Q | 2

ZOGENIX, INC.

CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE LOSS (Unaudited)

(In thousands)

	Three Months Ended March 31,
	2021		2020
Net loss	$	(55,630)	$	(25,800)
Other comprehensive (loss) income, net of tax:
Change in unrealized gains related to marketable securities	(112)		(172)
Foreign currency translation adjustments	146		5
Total other comprehensive income (loss)	34		(167)
Comprehensive loss	(55,596)		(25,967)

See accompanying notes to the unaudited condensed consolidated financial statements.

ZOGENIX, INC. | Q1 2021 Form 10-Q | 3

ZOGENIX, INC.

CONDENSED CONSOLIDATED STATEMENTS OF STOCKHOLDERS’ EQUITY (Unaudited)

(In thousands)

Three Months Ended March 31, 2021	Shares of Common Stock	Common Stock and Additional Paid-in Capital		Accumulated Deficit		Accumulated Other Comprehensive Loss		Total Stockholders’ Equity
Balance at December 31, 2020	55,736	$	1,694,580	$	(1,324,840)	$	(71)	$	369,669
Net loss	—	—		(55,630)		—		(55,630)
Other comprehensive income	—	—		—		34		34
Issuance of common stock under employee equity plans	120	6		—		—		6
Shares repurchased to satisfy tax withholding obligation of vesting restricted stock units	(43)	(896)		—		—		(896)
Stock-based compensation	—	8,098		—		—		8,098
Balance at March 31, 2021	55,813	$	1,701,788	$	(1,380,470)	$	(37)	$	321,281

Three Months Ended March 31, 2020	Shares of Common Stock	Common Stock and Additional Paid-in Capital		Accumulated Deficit		Accumulated Other Comprehensive Income		Total Stockholders’ Equity
Balance at December 31, 2019	45,272	$	1,360,137	$	(1,115,457)	$	379	$	245,059
Net loss	—	—		(25,800)		—		(25,800)
Other comprehensive loss	—	—		—		(167)		(167)
Issuance of common stock, net of offering costs	9,798	221,708		—		—		221,708
Issuance of common stock under employee equity plans	297	3,882		—		—		3,882
Shares repurchased to satisfy tax withholding obligation of vesting restricted stock units	(26)	(569)		—		—		(569)
Stock-based compensation	—	6,394		—		—		6,394
Balance at March 31, 2020	55,341	$	1,591,552	$	(1,141,257)	$	212	$	450,507

See accompanying notes to the unaudited condensed consolidated financial statements.

ZOGENIX, INC. | Q1 2021 Form 10-Q | 4

ZOGENIX, INC.

CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS (Unaudited)

(In thousands)

 

	Three Months Ended March 31,
	2021		2020
Cash flows from operating activities:
Net loss	$	(55,630)	$	(25,800)
Adjustments to reconcile net loss to net cash used in operating activities
Stock-based compensation	8,098		6,394
Depreciation and amortization	2,365		357
Amortization of debt discount and issuance costs	2,098		—
Acquired in-process research and development expense	—		1,500
Change in fair value of contingent consideration liability	600		(7,900)
Other non-cash items, net	236		(38)
Changes in operating assets and liabilities:
Accounts receivable	(2,295)		—
Inventory	(1,298)		—
Prepaid expenses and other current assets	1,150		(20,463)
Other non-current assets	108		(405)
Accounts payable, accrued and other current liabilities	(9,010)		(4,435)
Operating lease liabilities	(444)		(452)
Deferred revenue	164		(1,249)
Net cash used in operating activities	(53,858)		(52,491)
Cash flows from investing activities:
Cash paid for in-process research and development asset	—		(1,500)
Purchases of marketable securities	(141,652)		(15,695)
Proceeds from sale and maturities of marketable securities	130,888		54,605
Purchases of property and equipment	(87)		(193)
Net cash (used in) provided by investing activities	(10,851)		37,217
Cash flows from financing activities:
Payment of contingent consideration	(15,000)		—
Proceeds from issuance of common stock under equity incentive plans	6		2,040
Payments of tax withholding obligation on vesting restricted stock units	(896)		(569)
Proceeds from issuance of common stock, net of issuance costs	—		221,708
Net cash (used in) provided by financing activities	(15,890)		223,179
Net (decrease) increase in cash and cash equivalents	(80,599)		207,905
Cash and cash equivalents, beginning of the period	166,916		62,070
Cash and cash equivalents, end of the period	$	86,317	$	269,975
Supplemental Disclosure of Non-Cash Investing and Financing Activities:
Right-of-use assets obtained in exchange for new operating lease liabilities	$	—	$	1,156

See accompanying notes to the unaudited condensed consolidated financial statements.

ZOGENIX, INC. | Q1 2021 Form 10-Q | 5

ZOGENIX, INC.

NOTES TO CONDENSED CONSOLIDATED FINANCIAL STATEMENTS (Unaudited)

Note 1 – Organization, Basis of Presentation and Liquidity

Zogenix, Inc., and subsidiaries (also referred to as Zogenix, we, our or us) is a global biopharmaceutical company committed to developing and commercializing therapies with the potential to transform the lives of patients and their families living with rare diseases. Our first rare disease therapy, Fintepla (fenfluramine) oral solution, has been approved by the U.S. Food and Drug Administration (FDA) and the European Medicines Agency (EMA) for the treatment of seizures associated with Dravet syndrome, a rare, devastating, severe lifelong epilepsy. Fintepla is also currently under development in Japan. We also have two late-stage development programs underway: one for Fintepla for the treatment of seizures associated with Lennox-Gastaut syndrome (LGS), a rare childhood-onset epilepsy, and another for MT1621, an investigational novel substrate enhancement therapy for the treatment of TK2 deficiency, a rare genetic disorder.

We operate as a single operating segment engaged in the research, development and commercialization of pharmaceutical products, and our headquarters are located in Emeryville, California.

Basis of Presentation

The accompanying condensed consolidated financial statements have been prepared pursuant to generally accepted accounting principles in the United States (GAAP) for interim financial reporting and the rules and regulations of the Securities and Exchange Commission (SEC). The condensed consolidated financial statements do not include all of the information and note disclosures required by GAAP for complete financial statements and should therefore be read in conjunction with the consolidated financial statements and related notes included in our 2020 Annual Report on Form 10-K (2020 Form 10-K), which was filed with the SEC on March 1, 2021. In the opinion of management, these condensed consolidated financial statements reflect all adjustments, which are normal and recurring in nature, necessary for a fair statement of our financial position, results of operations and cash flows for the periods indicated. The results of operations for any interim period are not necessarily indicative of results of operations for any future period.

The accompanying condensed consolidated financial statements include the accounts of Zogenix, Inc. and its wholly-owned subsidiaries. Intercompany accounts and transactions have been eliminated in consolidation.

Liquidity

As of March 31, 2021, our cash, cash equivalents and marketable securities totaled $435.2 million. Excluding gains from two discrete business divestitures, we have incurred significant net losses and negative cash flows from operating activities since inception, resulting in an accumulated deficit of $1.4 billion as of March 31, 2021. We expect to continue to incur significant operating losses and negative cash flows from operations to support the sales and marketing of Fintepla for Dravet syndrome in the U.S. and Europe, potential commercialization of Fintepla for LGS, as well as continuing to advance our clinical programs. Additionally, we are obligated to make future milestone payments that are contingent upon the successful achievement of certain development, regulatory and sales-based milestone events related to Fintepla and MT1621. Historically, we have relied primarily on the proceeds from equity and convertible debt offerings to finance our operations. Until such time, if ever, we can generate a sufficient amount of revenue to finance our cash requirements, we may need to continue to rely on additional financing to achieve our business objectives. However, we may not be able to secure such financing in a timely manner or on favorable terms, if at all, and this risk could be exacerbated by the impact of COVID-19 on global economic conditions. Failure to raise sufficient capital when needed could require us to significantly delay, scale back or discontinue one or more of our product development programs or commercialization efforts or other aspects of our business plans, and our operating results and financial condition would be adversely affected.

Note 2 – Accounting Policies

Use of Estimates

The preparation of our condensed consolidated financial statements requires us to make estimates, judgments and assumptions that may affect the reported amounts of assets, liabilities, equity, revenues and expenses and related disclosure of contingent assets and liabilities. On an ongoing basis we evaluate our estimates, judgments and methodologies. We base our estimates on historical experience and on various other assumptions that we believe are reasonable, the results of which form the basis for making judgments about the carrying values of assets, liabilities and equity and the amount of revenues and expenses. Actual results may differ from those estimates.

ZOGENIX, INC. | Q1 2021 Form 10-Q | 6

Significant Accounting Policies

The significant accounting policies and estimates used in the preparation of the accompanying condensed consolidated financial statements are described in Note 2, Summary of Significant Accounting Policies to the consolidated financial statements in our 2020 Form 10-K. There have been no material changes in our significant accounting policies during the three months ended March 31, 2021.

Recently Issued Accounting Pronouncements Not Yet Adopted

Account Standard Update (ASU) 2020-06, Debt — Debt with Conversion and Other Options (subtopic 470-20) and Derivatives and Hedging — Contracts in Entity’s Own Equity (subtopic 815-40) (ASU 2020-06) simplifies the accounting for certain financial instruments with characteristics of liabilities and equity, including convertible debt instruments with cash conversion features. Specifically, ASU 2020-06 removes the existing guidance that we currently follow for our convertible senior notes, which requires entities to account for cash conversion features in equity separately from the host contract. These amendments are expected to result in more freestanding financial instruments qualifying for equity classification and, as a result, not accounted for as derivatives, as well as fewer embedded features requiring separate accounting from the host contract. In addition, ASU 2020-06 eliminates the treasury stock method when calculating diluted earnings per share for convertible instruments that can be settled in whole or in part with equity and requires the use of the if-converted method. Early adoption is permitted, but no earlier than the fiscal year beginning after December 15, 2020. The standard can be applied using a full or modified retrospective approach.    

ASU 2020-06 will be effective for us as of January 1, 2022. When effective, we expect the accounting for our convertible senior notes as a single unit of account will: i) increase the carrying value of our convertible notes to be closer to its outstanding principal balance, ii) decrease our interest expense over the expected life of the financial instrument, and iii) result in the debt instrument’s effective interest rate to be closer to the stated coupon rate. In addition, the use of the more favorable treasury stock method, which allows an entity with a stated policy of settling convertible instruments with a combination of cash and shares to exclude shares issuable upon conversion that it expects to settle with cash when calculating diluted earnings per share, is no longer permitted. Even if we have the intent and ability to settle conversions by paying the conversion value in cash up to the principal amount being converted and any excess in shares, the adoption of ASU 2020-06 will require that we presume such instruments will be settled by issuance of shares (the “if-converted method”). As a result, our diluted earnings per share under ASU 2020-06 may be lower than if we were able to apply the treasury stock method when calculating the dilutive effect of our Notes in earnings per share.

Note 3 – Product Revenue and Concentration of Credit Risks

Net Product Sales

Fintepla is distributed in the U.S. through an exclusive arrangement with a specialty distributor, who is our customer. The specialty distributor subsequently resells our product through its related specialty pharmacy provider to patients and health care providers. Separately, we have or may enter into payment arrangements with various third-party payers including pharmacy benefit managers, private healthcare insurers and government healthcare programs who provide coverage and reimbursement for our products that have been proscribed to a patient.

In February 2021, we began to distribute Fintepla in Europe (currently, in Germany) through a third-party logistics provider (3PL) for distribution to pharmacies throughout Germany. The pharmacies are our customers, who subsequently resell our product directly to patients and health care providers.

For the three months ended March 31 ,2021, total net product sales generated from Fintepla was $12.3 million, and consisted of $11.3 million derived in the United States and $1.0 million derived in Germany. Fintepla was approved by the FDA in June 2020 and the EMA in December 2020.

We record product revenue at the net sales price (transaction price), which includes estimates of consideration payable to our customers and third-party payers for which reserves are established and that result from government rebates, chargebacks, co-pay assistance, prompt-payment discounts and other allowances that are offered under arrangements between us, our customers, and third-party payers related to the sales of Fintepla.

The following table summarizes the provisions, and credits/payments, for sales-related deductions.

ZOGENIX, INC. | Q1 2021 Form 10-Q | 7

(In thousands)	Rebates		Trade Discounts, Distributor Fees and Other		Total
Balance at December 31, 2020	$	1,161	$	129	$	1,290
Current period provisions	1,904		593		2,497
Credits/payments	(774)		(481)		(1,255)
Balance at March 31, 2021	$	2,291	$	241	$	2,532

We generally invoice our customers and recognize revenue once our performance obligations are satisfied, at which point payment is unconditional. Accordingly, our arrangements with customers did not give rise to contract assets or liabilities during the three months ended March 31, 2021.

Concentration of Credit Risk and Major Customers

As is common in the pharmaceutical industry for products treating rare diseases, Fintepla is distributed through exclusive arrangements with a specialty distributor in the U.S. and through a 3PL who distributes to pharmacy providers throughout Germany. As a result, our accounts receivable balance at March 31, 2021 is highly concentrated with our U.S. customer accounting for over 90% of the balance and over 90% of net product revenue for the three months ended March 31, 2021. Accounts receivable are stated net of an allowance that reflects our current estimate of credit losses expected to occur over the life of the receivable. Estimates of our allowance for credit losses consider a number of factors including existing contractual payment terms, individual customer circumstances, historical payment patterns of our customers, a review of the local economic environment and its potential impact on expected future customer payment patterns. As of March 31, 2021 and December 31, 2020, we believe that the allowances for doubtful accounts, if any, are adequate based on our analysis of the specific business circumstances and expectations of collection for each of the underlying accounts.

Note 4 – Collaboration Arrangement

Nippon Shinyaku Co., Ltd

In March 2019, we entered into an agreement (Shinyaku Agreement) with Nippon Shinyaku Co., Ltd. (Shinyaku) for the exclusive distribution of Fintepla in Japan for the treatment of Dravet syndrome and LGS. No development rights or intellectual property licenses were transferred. As part of the Shinyaku Agreement, we are responsible for completing the global clinical development and all regulatory approval activities for Fintepla to support the submission of new drug applications in Japan for Dravet syndrome and LGS. Upon regulatory approval of Fintepla in Japan, Shinyaku will act as our exclusive distributor for Fintepla and will be responsible for the commercialization activities including the promotion, marketing, sale and distribution of Fintepla in Japan.

Shinyaku has agreed to support development and regulatory approval of Fintepla in Japan by actively participating in the design of non-clinical, clinical and manufacturing requirements needed for regulatory submission, actively planning and participating in product labeling decisions and discussions with the Japanese Ministry of Health, Labor and Welfare (MHLW) and obtained distribution exclusivity through the payment of an initial fixed consideration. The collaborative activities under the Shinyaku Agreement prior to regulatory approval are within the scope of the accounting guidance related to collaborative arrangements.

Pursuant to the terms of the agreement, Shinyaku agreed to make aggregate fixed payments of $20.0 million in scheduled installments over a two-year period from the date of the agreement. As of March 31, 2021, all fixed consideration has been received. In addition, we can earn up to $66.0 million from Shinyaku for the achievement of certain regulatory milestones for the treatment of Dravet syndrome and LGS. At contract inception and through March 31, 2021, the regulatory milestone variable consideration was fully constrained as the achievement of the events tied to these regulatory milestone payments was highly dependent on factors outside our control.

We can earn up to an additional $42.5 million tied to the achievement of certain net sales milestones by Shinyaku through the term of the agreement, which generally expires in 2045. Shinyaku will only become a customer and subject to revenue from contracts from customers accounting guidance after regulatory approval of Fintepla in Japan occurs and Shinyaku places purchase orders with us. To date, Shinyaku has not provided us with any purchase orders and thus no revenue has been recognized for the supply of Fintepla.

For the three months ended March 31, 2021 and 2020, collaboration revenue under this arrangement was $1.3 million and $1.2 million, respectively. As of March 31, 2021, the deferred revenue balance of $11.0 million was classified as either current or net of current portion in the accompanying condensed consolidated balance sheets

ZOGENIX, INC. | Q1 2021 Form 10-Q | 8

based on the period over which the collaboration revenue is expected to be recognized. We expect to recognize collaboration revenue related to these collaborative activities through the end of 2023.

Note 5 – Strategic License Agreement

Tevard Collaboration, Option and License Agreement

In October 2019, we entered into an option agreement with Tevard Biosciences (Tevard), a privately-held company focused on advancing novel gene therapies and other genetic epilepsies. In December 2020, we exercised the option on Tevard’s Dravet syndrome program and entered into a collaboration, option and license agreement with Tevard (the Tevard Agreement) and will be responsible for funding preclinical studies and clinical development for this program. The financial terms of the Tevard Agreement included an upfront payment of $5.2 million. In connection with the transaction, we also purchased a convertible promissory note issued by Tevard in the amount of $5.0 million. The note matures in December 2022 and carries interest at 3.5% per year. The note will automatically convert into equity securities issued by Tevard in their next equity financing transaction at a conversion price equal to the price paid per share by other investors of the financing transaction.

For the three months ended March 31, 2021, amounts payable to reimburse Tevard for its costs incurred under the Dravet syndrome program of $0.8 million were recorded as research and development expense. For the three months ended March 31, 2020, option maintenance fees of $1.5 million incurred prior to our opt-in of Tevard’s Dravet syndrome program in December 2020 were immediately expensed to acquired in-process research and development costs.

At the inception of the agreement and through March 31, 2021, Tevard is a variable interest entity in which we held variable interests through our licensed Dravet syndrome program and convertible promissory note. We determined that we are not the primary beneficiary of Tevard as we do not have voting control or other forms of power to direct activities that most significantly impact Tevard’s economic performance.

At each reporting period, we evaluate the note receivable for current expected credit loss by considering factors such as historical experience, market data, issuer-specific factors, and current economic conditions. As of March 31, 2021, no provision for current expected credit losses was deemed necessary based on the expected timing of an equity financing that would result in the automatic conversion of the note to equity securities of Tevard and their existing cash on hand was sufficient to meet their operating requirements prior to the consummation of a financing transaction.

As of March 31, 2021, we do not have any current legal or contractual obligations to provide financing to Tevard and our maximum exposure to future loss is limited to the $5.0 million note receivable. While we have committed to fund the Dravet syndrome development program for Tevard’s early discovery activities, our obligation to fund these efforts is contingent upon continued involvement in the program and/or the lack of any adverse events which could cause the discontinuance of the program. Our exposure to future losses is limited as we have the unilateral right to terminate the agreement with 180 days advanced notice.

Note 6 – Cash, Cash Equivalents and Marketable Securities

The following tables summarize the amortized cost and the estimated fair value of our cash, cash equivalents and marketable securities as of March 31, 2021 and December 31, 2020:

ZOGENIX, INC. | Q1 2021 Form 10-Q | 9

	March 31, 2021
(In thousands)	Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses		Estimated Fair Value
Current assets:
Cash	$	26,847	$	—	$	—	$	26,847
Cash equivalents:
Money market funds	38,974		—		—		38,974
Certificate of deposits	1,500		—		—		1,500
Commercial paper	18,996		—		—		18,996
Total cash and cash equivalents	86,317		—		—		86,317
Marketable securities:
U.S. Treasuries	26,924		6		—		26,930
Certificate of deposits	55,283		—		—		55,283
Commercial paper	233,419		—		—		233,419
Corporate debt securities	27,002		59		(2)		27,059
U.S. Government-sponsored enterprises debt securities	6,200		14		—		6,214
Total marketable securities	348,828		79		(2)		348,905
Total cash, cash equivalents and marketable securities	$	435,145	$	79	$	(2)	$	435,222

	December 31, 2020
(In thousands)	Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses		Estimated Fair Value
Current assets:
Cash	$	23,887	$	—	$	—	$	23,887
Cash equivalents:
Money market funds	80,986		—		—		80,986
Commercial paper	61,043		—		—		61,043
Certificate of deposits	1,000		—		—		1,000
Total cash equivalents	143,029		—		—		143,029
Total cash and cash equivalents	166,916		—		—		166,916
Marketable securities:
U.S. Treasuries	43,050		1		(1)		43,050
Commercial paper	210,986		—		—		210,986
Certificate of deposits	44,480		—		—		44,480
U.S. Government-sponsored enterprises debt securities	6,200		17		—		6,217
Corporate debt securities	33,288		172		—		33,460
Total marketable securities	338,004		190		(1)		338,193
Total cash, cash equivalents and marketable securities	$	504,920	$	190	$	(1)	$	505,109

As of March 31, 2021, all marketable securities held have maturity dates within one year or less. We regularly review our available-for-sale marketable securities in an unrealized loss position and evaluate the current expected credit loss by considering factors such as historical experience, market data, issuer-specific factors, and current economic conditions. As of March 31, 2021, the aggregate difference between the amortized cost and fair value of each security in an unrealized loss position was de minimis. Since any provision for expected credit losses for a security held is limited to the amount the fair value is less than its amortized cost, no allowance for expected credit loss was deemed necessary at March 31, 2021.

See Note 7 for further information regarding the fair value of our financial instruments.

ZOGENIX, INC. | Q1 2021 Form 10-Q | 10

Note 7 – Fair Value Measurements

Fair value is defined as the price that would be received to sell an asset or paid to transfer a liability (an exit price) in the principal or most advantageous market for the asset or liability in an orderly transaction between market participants on the measurement date. A three-level valuation hierarchy has been established under GAAP for disclosure of fair value measurements. The valuation hierarchy is based on the transparency of inputs to the valuation of an asset or liability as of the measurement date. The three levels are defined as follows:

Level 1:Observable inputs such as quoted prices in active markets;

Level 2:Inputs, other than the quoted prices in active markets, that are observable either directly or indirectly; and

Level 3:Unobservable inputs in which there is little or no market data, which require the reporting entity to develop its own assumptions.

Our financial instruments consist primarily of cash and cash equivalents, marketable securities, notes receivable and other current assets, accounts payable and accrued liabilities, convertible senior notes and contingent consideration liability, and are reported at their respective fair values on our condensed consolidated balance sheets. The remaining financial instruments are carried at cost which approximates their respective fair values because of the short-term nature of these financial instruments. See Note 6 for further information regarding the amortized cost of our financial assets.

The following tables summarize assets and liabilities recognized or disclosed at fair value on a recurring basis as of March 31, 2021 and December 31, 2020:

	March 31, 2021
(In thousands)	Level 1		Level 2		Level 3		Total
Assets:
Cash equivalents:
Money market funds	$	38,974	$	—	$	—	$	38,974
Certificate of deposits	—		1,500		—		1,500
Commercial paper	—		18,996		—		$	18,996
Marketable securities:
U.S. Treasury securities	—		26,930		—		26,930
Certificate of deposits	—		55,283		—		55,283
Commercial debt securities	—		233,419		—		233,419
Commercial paper	—		27,059		—		27,059
U.S. Government-sponsored enterprises debt securities	—		6,214		—		6,214
Total(1)	$	38,974	$	369,401	$	—	$	408,375
Liabilities:
Contingent consideration	$	—	$	—	$	43,000	$	43,000

ZOGENIX, INC. | Q1 2021 Form 10-Q | 11

	December 31, 2020
(In thousands)	Level 1		Level 2		Level 3		Total
Assets:
Cash equivalents:
U.S. Treasuries	$	—	$	13,799	$	—	$	13,799
Money market funds	39,536		—		—		39,536
Certificate of deposits	—		3,008		—		3,008
Commercial paper	—		21,648		—		21,648
Marketable securities:
U.S. Treasuries	—		27,896		—		27,896
Commercial paper	—		101,951		—		101,951
U.S. Government-sponsored enterprises debt securities	—		6,219		—		6,219
Corporate debt securities	—		50,357		—		50,357
Certificate of deposits	—		41,284		—		41,284
Total(1)	$	39,536	$	266,162	$	—	$	305,698
Liabilities:
Contingent consideration	$	—	$	—	$	42,400	$	42,400

————————————

(1)Fair value is determined by taking into consideration valuations obtained from third-party pricing services. The third-party pricing services utilize industry standard valuation models, for which all significant inputs are observable, either directly or indirectly, to estimate fair value. These inputs include reported trades of and broker/dealer quotes on the same or similar securities; issuer credit spreads; benchmark securities; and other observable inputs.

Contingent Consideration Liability

As of March 31, 2021, our contingent consideration liability consisted of sales-based milestones for Fintepla, which resulted from our 2014 acquisition of Brabant. The maximum amount of future contingent consideration (undiscounted) that we could be required to pay was $45.0 million.

The following table provides a reconciliation of our contingent consideration liability measured at fair value on a recurring basis using significant unobservable inputs (Level 3) for the three months ended March 31, 2021 and 2020 (in thousands):

	Three Months Ended March 31,
	2021		2020
Balance at beginning of period	$	42,400	$	63,800
Change in fair value	600		(7,900)
Balance at end of period	$	43,000	$	55,900

For the three months ended March 31, 2021, the $0.6 million increase to the estimated fair value of the contingent consideration liability reflects the interest component of contingent consideration related to the passage of time. For the three months ended March 31, 2020, the $7.9 million was primarily due to changes to our probability-weighted estimates for achieving regulatory/commercial milestones and the use of a higher discount rate to reflect an increase in credit-adjusted interest rates.

The following table summarizes the significant unobservable inputs used in the fair value measurement of our contingent consideration liabilities as of March 31, 2021.

ZOGENIX, INC. | Q1 2021 Form 10-Q | 12

Fair Value as of March 31, 2021 (in thousands)	Valuation Technique	Unobservable Input	Range	Weighted Average(1)
$43,000	Discounted cash flow	Discount rate	1.9% — 3.0%	2.5%
		Probability of payment	100%	100%
		Projected year of payment	2021 — 2030	2022

————————————

(1)Unobservable inputs were weighted by the relative fair value of each sales-based milestone payment.

Convertible Senior Notes

As of March 31, 2021 and December 31, 2020, the estimated fair value of our convertible senior notes due 2027 was approximately $259.8 million and $260.5 million, respectively, and was determined based on a binomial lattice model with Level 2 inputs. When determining the estimated fair value of our Notes, we utilize a binomial lattice model which incorporates the terms and conditions of our convertible senior notes and market-based risk measurements that are indirectly observable, such as credit risk. The lattice model produces an estimated fair value based on changes in the price of the underlying common stock price over successive periods of time. An estimated yield based on comparable non-convertible debt instruments in the market is used to discount the cash flows.

Note 8 – Intangible Asset

Our intangible asset consists of worldwide development, commercialization and related intellectual property rights including patents and licenses for Fintepla, our first rare disease therapy approved for marketing in the U.S. and Europe.

The following table provides details of the carrying amount of our finite-lived intangible asset:

(In thousands)	March 31, 2021		December 31, 2020
Finite-lived intangible asset	$	102,500	$	102,500
Accumulated amortization	(5,913)		(3,942)
Total intangible asset, net	$	96,587	$	98,558

As of March 31, 2021 and December 31, 2020, the carrying value of the intangible asset will be amortized over its estimated remaining useful life of 12.3 years and 12.5 years, respectively. At March 31, 2021, the estimated amortization expense for each of the five succeeding years was approximately $7.9 million per year.

Note 9 – Balance Sheet Details

Inventory

The following table provides details of our inventory balance:

(In thousands)	March 31, 2021		December 31, 2020
Raw materials	$	659	$	391
Work in process	755		243
Finished goods	910		392
Total	$	2,324	$	1,026

ZOGENIX, INC. | Q1 2021 Form 10-Q | 13

Accrued and Other Current Liabilities

The following table provides details of accrued and other current liabilities:

(In thousands)	March 31, 2021		December 31, 2020
Accrued clinical trial expenses	$	14,405	$	16,477
Accrued compensation	7,135		10,917
Accrued milestone payment	—		15,000
Other accrued liabilities	9,209		12,570
Total	$	30,749	$	54,964

Note 10 – Convertible Senior Notes

In September and October 2020, we issued $230.0 million aggregate principal amount of 2.75% convertible senior notes due 2027 (the Notes) and realized net proceeds of $222.5 million. The Notes are governed by an indenture (Indenture), dated as of September 28, 2020, between Zogenix and U.S. Bank National Association, as trustee. Under the Indenture, the Notes are senior, unsecured obligations of Zogenix, are equal in right of payment with its future senior, unsecured indebtedness of Zogenix, and structurally subordinated to all indebtedness and liabilities of its subsidiaries. Interest is payable semi-annually in arrears on April 1 and October 1 of each year, beginning on April 1, 2021 at a rate of 2.75% per year. The Notes mature on October 1, 2027, unless earlier repurchased, redeemed or converted. The Indenture contains customary terms and covenants and may become due and payable upon the occurrence of an event of default, but does not contain any financial covenants. As of March 31, 2021, we were in compliance with all covenants under the Indenture.

The Notes are convertible, subject to certain conditions described below, into shares of our common stock at an initial conversion rate of 41.1794 shares per $1,000 principal amount of the Notes, which represents an initial conversion price of approximately $24.28 per share, subject to adjustments upon the occurrence of certain events. Certain corporate events described in the Indenture may increase the conversion rate for holders who elect to convert their Notes in connection with such corporate event should they occur. We also may choose to repurchase outstanding Notes through open-market transactions, including through Rule 10b5-1 trading plan to facilitate open-market repurchases, or otherwise, from time to time.

Holders may convert the Notes in multiples of $1,000 principal amount at any time prior to October 1, 2027, but only in the following circumstances:

•during any calendar quarter ending after December 31, 2020, if our closing stock price exceeds 130% of the conversion price on each of at least 20 trading days of the last 30 consecutive trading days of the immediately preceding calendar quarter;

•during the five consecutive business day period after any 10 consecutive trading day period in which the Notes’ trading price is less than 98% of the product of our closing stock price times the conversion rate; or

•the occurrence of certain corporate events, such as a change of control, merger, default or liquidation.

In addition, holders may also convert their Notes at their option at any time beginning on July 1, 2027 until the close of business on the second scheduled trading day immediately before the maturity date for the Notes, without regard to the foregoing circumstances.

Upon conversion, we will pay or deliver, as the case may be, cash, shares of our common stock or a combination thereof at our election.

We may not redeem the Notes prior to October 7, 2024. On or after October 7, 2024, the Notes are redeemable for cash, in whole or in part (subject to minimum redemption amounts), at our option at any time, and from time to time, before the 40th scheduled trading day immediately before October 1, 2027, at a cash redemption price equal to 100% of the principal amount of the Notes to be redeemed, plus accrued and unpaid interest, if any, but only if our closing stock price exceeds 130% of the conversion price on (1) each of at least 20 trading days, whether or not consecutive, during the 30 consecutive trading days ending on, and including, the trading day immediately before the date we send the related redemption notice; and (2) the trading day immediately before the date we send such notice. In addition, calling any Note for redemption will constitute a make-whole fundamental change (as defined in the Indenture) with respect to that Note, in which case the conversion rate applicable to the conversion of that Note will be increased in certain circumstances if it is converted after it is called for redemption.

ZOGENIX, INC. | Q1 2021 Form 10-Q | 14

In accounting for the issuance of the Notes, we separated the Notes between a liability component and an equity component utilizing applicable guidance for convertible instruments that may be settled with a combination of cash and shares, at our election. This resulted in the recognition of $152.1 million as the liability component of the Notes. The carrying amount of the equity component of approximately $77.9 million, representing the conversion option, was determined by deducting the fair value of the liability component from the principal amount of the Notes. The difference between the principal amount of the Notes and the liability component (the debt discount) is amortized to interest expense using the effective interest method over the expected term of the Notes. The equity component of the Notes is included in additional paid-in capital in the condensed consolidated balance sheets. In accounting for debt issuance costs, we allocated the total amount incurred of $7.5 million to the liability and equity components using the same proportions as the principal amount of the Notes. Debt issuance costs attributable to the liability component of $4.9 million were recorded as debt discount and are being amortized to interest expense over the expected term of the Notes. Debt issuance costs attributable to the equity component of approximately $2.6 million were netted with the equity component within our condensed consolidated stockholders' equity.

The equity component balance of $75.3 million, net of allocated issuance costs, is not remeasured as long as the conversion option of the Notes continues to meet the conditions for equity classification. As of March 31, 2021, there have been no changes to the net carrying value of the equity component balance since the date of issuance of the Notes.

The following table provides additional details on the carrying amounts of our:

(in thousands)	March 31, 2021		December 31, 2020
Liability component:
Principal amount of Notes	$	230,000	$	230,000
Less: unamortized debt discount and issuance costs	(78,549)		(80,647)
Net carrying amount of Notes	$	151,451	$	149,353
Equity component — net carrying amount	$	75,333	$	75,333

For the three months ended March 31, 2021, total interest expense recognized related to our Notes consists of the following:

(in thousands)	Three Months Ended March 31, 2021
Contractual coupon interest	1,615
Amortization of debt discount and issuance costs	2,098
Total interest expense	$	3,713

For the three months ended March 31, 2021, the effective interest rate on the liability component of the Notes was 9.9%, which remained unchanged from the date of issuance. The unamortized debt discount and issuance costs of $78.5 million as of March 31, 2021 will be amortized over the remaining term of approximately 6.5 years. We had no interest expense for the same period in 2020 as we had no borrowings.

During the three months ended March 31, 2021, the closing price of our common stock did not exceed 130% of the applicable conversion price of our Notes on at least 20 of the last 30 consecutive trading days of the quarter; furthermore, no other conditions allowing holders of the Notes to convert have been met as of March 31, 2021. Therefore, the Notes are not convertible for the three months ending June 30, 2021 and are classified as long-term debt. Should the closing price conditions be met in a future quarter, the Notes will be convertible at the holders’ option during the immediately following quarter. Based on the closing price of our common stock of $19.52 per share on March 31, 2021, the if-converted value of the Notes was less than the outstanding principal balance.

Note 11 – Stock-Based Compensation

Stock Options

The following is a summary of stock option activity for the three months ended March 31, 2021 (in thousands, except per share data):

ZOGENIX, INC. | Q1 2021 Form 10-Q | 15

	Shares	Weighted- Average Exercise Price per Share
Outstanding at December 31, 2020	5,311	$	29.12
Granted	946	18.96
Exercised	(1)	10.33
Canceled	(75)	33.73
Outstanding at March 31, 2021	6,181	$	27.51

Restricted Stock Units

Time-based restricted stock units (RSUs) and performance-based restricted stock units (PSUs) will be settled with our common stock on a one-to-one basis upon vesting. The following is a summary of our stock award activity for the three months ended March 31, 2021 (in thousands, except per share data):

	RSUs		PSUs		Total
December 31, 2020	393		—		393
Granted(1)	450		482		932
Vested	(119)		—		(119)
Canceled	(6)		(3)		(9)
Outstanding at March 31, 2021	718		479		1,197
(1) Weighted-average grant date fair value	$	18.76	$	19.60	$	19.20

For the three months ended March 31, 2021, we granted 0.5 million PSUs to employees and executive officers. The PSUs are subject to vesting based on various performance conditions including achievement of certain regulatory milestones, net product revenue targets and the number of patients with reimbursed therapy, subject to continued service by the employee. Compensation expense related to equity-based awards with performance conditions and terms that provide for a graded vesting schedule is recognized over the requisite service period on a straight-line basis for each separately vesting tranche of the award, and is based on the expected satisfaction of the performance conditions at each reporting date. For performance conditions associated with regulatory milestones, we determined the outcome is not probable of being achieved unless and until the occurrence of the event. As a result, compensation expense will only be recognized, at a point in time, when regulatory approval occurs. We expect stock-based compensation will fluctuate from period to period based on the timing of achievement of regulatory milestones and such fluctuations may be material. For performance conditions associated with the net product revenue and the number of patients receiving reimbursed therapy, we determined the outcome is probable of being achieved and stock-based compensation expense is recognized commencing at the grant date over the implicit service period.

The following table summarizes the components of total stock-based compensation expense included in our condensed consolidated statements of operations:

	Three Months Ended March 31,
(In thousands)	2021		2020
Research and development	$	3,299	$	2,729
Selling, general and administrative	4,799		3,665
Total	$	8,098	$	6,394

The following table summarizes stock-based compensation expense by award type included in our condensed consolidated statements of operations:

ZOGENIX, INC. | Q1 2021 Form 10-Q | 16

	Three Months Ended March 31,
(In thousands)	2021		2020
Time-based stock options and restricted stock units	$	7,475	$	6,242
Performance-based stock units	427		—
Employee stock purchase plan (ESPP)	196		152
Total	$	8,098	$	6,394

Shares reserved and available for future issuance under all employee equity plans as of March 31, 2021 and December 31, 2020 were 2.1 million shares and 3.9 million shares, respectively.

Note 12 – Net Loss Per Share

Basic net loss per share is calculated by dividing net loss by the weighted average number of shares outstanding for the period. Diluted net loss per share is calculated by dividing net loss by the weighted average number of shares of common stock and potential dilutive common stock equivalents outstanding during the period if the effect is dilutive. Our potentially dilutive shares of common stock include outstanding stock options, restricted stock units, warrants to purchase common stock and rights under our Notes.

A reconciliation of the numerators and denominators used in computing net loss per share is as follows (in thousands, except per share amounts):

	Three Months Ended March 31,
	2021		2020
Numerator:
Net loss	$	(55,630)	$	(25,800)
Denominator:
Shares used in per share calculation	55,750		48,185
Net loss per share, basic and diluted	$	(1.00)	$	(0.54)

The following table presents the potential shares of common stock outstanding that were excluded from the calculation of diluted net loss per share for the periods presented because including them would have been anti-dilutive (in thousands):

	Three Months Ended March 31,
	2021	2020
Shares subject to outstanding stock options	5,476	4,450
Shares subject to outstanding restricted stock units	738	485
Shares subject to outstanding warrants to purchase common stock	28	28
Shares issuable upon conversion of Notes	9,430	—
Total	15,672	4,963

Note 13 – United Kingdom (U.K.) Research and Development (R&D) Tax Relief Scheme

We conduct extensive research and development activities that benefit from U.K.’s small and medium-sized enterprises (SMEs) R&D tax relief scheme. Under this tax relief scheme, a SME can make an election (i) to receive an enhanced U.K. tax deduction on its eligible R&D activities or, when an SME entity is in a net operating loss position, or (ii) to surrender net operating losses that arise from its eligible R&D activities in exchange for a cash payment from the U.K. tax authorities. As the tax incentives may be received without regard to an entity’s actual tax liability, they are not subject to accounting for income taxes. Amounts recognized by us for cash payment claims under the SME R&D tax relief scheme are recorded as a component of other income after an election for tax relief has been made by submitting a claim for a discrete tax year and collectability is deemed probable and reasonably assured.

ZOGENIX, INC. | Q1 2021 Form 10-Q | 17

In December 2019, we elected to surrender net operating losses by submitting claims to receive cash payments of $9.9 million and $9.8 million related to our 2017 and 2018 tax years, respectively. Upon approval of our submitted claims by the U.K. tax authorities in the first quarter of 2020, we recorded income of $19.7 million as a component of other income on the condensed consolidated statement of operations. For our 2019 tax year, we have not yet decided whether to seek tax relief by surrendering some of our losses for a tax credit cash rebate claim or electing to receive enhanced U.K. tax deductions on our eligible research and development activities. Under the U.K.’s tax legislation, there is a two-year window after the end of a tax year to seek relief under this tax relief scheme.

ZOGENIX, INC. | Q1 2021 Form 10-Q | 18

Item 2. Management’s Discussion and Analysis of Financial Condition and Results of Operations.

Forward-Looking Statements

This Quarterly Report on Form 10-Q contains forward-looking statements that involve substantial risks and uncertainties. These forward-looking statements include, but are not limited to, statements about:

•our ability to commercialize Fintepla;

•the progress and timing of clinical trials of Fintepla and MT1621;

•the safety and efficacy of our product candidates;

•the impact of COVID-19 pandemic;

•the timing of submissions to, and decisions made by the U.S. Food and Drug Administration (FDA), the European Medicines Agency (EMA) and other regulatory agencies, including foreign regulatory agencies, with regards to the demonstration of the safety and efficacy of our product candidates and adequacy of the manufacturing processes related to our product candidates to the satisfaction of the FDA and such other regulatory agencies;

•our ability to obtain, maintain and successfully enforce adequate patent and other intellectual property or regulatory exclusivity protection of our product candidates and the ability to operate our business without infringing the intellectual property rights of others;

•the goals of our development activities and estimates of the potential markets for our product candidates, and our ability to compete within those markets;

•our ability to obtain and maintain adequate levels of coverage and reimbursement from third-party payors for any of our product candidates that may be approved for sale, the extent of such coverage and reimbursement and the willingness of third-party payors to pay for our products versus less expensive therapies;

•the impact of healthcare reform laws; and

•projected cash needs and our expected future revenues, operations and expenditures.

The forward-looking statements are contained principally in the sections entitled “Risk Factors” and “Management’s Discussion and Analysis of Financial Condition and Results of Operations.” In some cases, you can identify forward-looking statements by the following words: “may,” “will,” “could,” “would,” “should,” “expect,” “intend,” “plan,” “anticipate,” “believe,” “estimate,” “predict,” “project,” “potential,” “continue,” “ongoing” or the negative of these terms or other comparable terminology, although not all forward-looking statements contain these words. These statements relate to future events or our future financial performance or condition and involve known and unknown risks, uncertainties and other factors that could cause our actual results, levels of activity, performance or achievement to differ materially from those expressed or implied by these forward-looking statements. We discuss many of these risks, uncertainties and other factors in this Quarterly Report on Form 10-Q in greater detail under the heading “Item 1A – Risk Factors.”

Given these risks, uncertainties and other factors, we urge you not to place undue reliance on these forward-looking statements, which speak only as of the date of this report. You should read this Quarterly Report on Form 10-Q completely and with the understanding that our actual future results may be materially different from what we expect. For all forward-looking statements, we claim the protection of the safe harbor for forward-looking statements contained in the Private Securities Litigation Reform Act of 1995. We undertake no obligation to revise or update publicly any forward-looking statements, whether as a result of new information, future events or otherwise, unless required by law.

Fintepla® and Zogenix™ are our trademarks. All other trademarks, trade names and service marks appearing in this Quarterly Report on Form 10-Q are the property of their respective owners. Use or display by us of other parties’ trademarks, trade dress or products is not intended to and does not imply a relationship with, or endorsements or sponsorship of, us by the trademark or trade dress owner.

Unless the context requires otherwise, references in this Quarterly Report on Form 10-Q to “Zogenix,” “we,” “us” and “our” refer to Zogenix, Inc., a Delaware corporation, and its consolidated subsidiaries.

The condensed consolidated financial statements and this Management’s Discussion and Analysis of Financial Condition and Results of Operations should be read in conjunction with the consolidated financial statements and notes thereto for the year ended December 31, 2020 and the related Management’s Discussion and

ZOGENIX, INC. | Q1 2021 Form 10-Q | 19

Analysis of Financial Condition and Results of Operations, both of which are contained in our 2020 Annual Report on Form 10-K, which was filed with the SEC on March 1, 2021.

ZOGENIX, INC. | Q1 2021 Form 10-Q | 20

Overview

We are a global biopharmaceutical company committed to developing and commercializing therapies with the potential to transform the lives of patients and their families living with rare diseases. Our first rare disease therapy, Fintepla (fenfluramine) oral solution has been approved by the U.S. Food and Drug Administration (FDA) and the European Medicines Agency (EMA) for the treatment of seizures associated with Dravet syndrome, a rare, severe lifelong epilepsy. We have two additional late-stage development programs underway: Fintepla for the treatment of seizures associated with Lennox-Gastaut syndrome (LGS), another rare epilepsy and MT1621, an investigational therapy for the treatment of TK2 deficiency (TK2d), a rare genetic disease.

Fintepla for Patients with Rare Epilepsy Disorders

Dravet Syndrome

On June 25, 2020, the FDA granted approval of Fintepla for the treatment of seizures associated with Dravet syndrome in patients 2 years of age and older. During the third quarter of 2020, we commercially launched Fintepla through a restricted distribution program, called the Fintepla Risk Evaluation and Mitigation Strategy (REMS) Program. On December 18, 2020, the EMA granted marketing authorization for Fintepla for the treatment of seizures associated with Dravet syndrome as an add-on therapy to other anti-epileptic medicines for patients two years of age and older. Fintepla is available in Europe under a controlled access program requested by the EMA to prevent off-label use for weight management and to confirm that prescribing physicians have been informed of the need for periodic cardiac monitoring in patients taking Fintepla. We launched Fintepla for sale in Germany in February 2021 and expect to expand into other European markets thereafter. The approval for marketing of Fintepla in the U.S. and Europe was based on positive safety and efficacy results from two randomized, international, multi-center, placebo-controlled Phase 3 trials (Study 1 and Study 2), as well as data from an interim analysis of a long-term, open-label extension study in 330 Dravet syndrome patients treated up to three years.

In September 2020, we reported positive top-line results from our third Phase 3 trial (Study 3) of Fintepla for the treatment of seizures associated with Dravet syndrome. Study 3 corroborates the substantial impact of Fintepla on convulsive seizure reduction in patients with Dravet syndrome as previously demonstrated in Studies 1 and 2. Study 3 expands the countries where Fintepla has been evaluated to include Japan. In March 2019, we entered into an exclusive distribution agreement (Shinyaku Agreement) with Nippon Shinyaku Co., Ltd. (Shinyaku) for the potential commercialization of Fintepla in Japan. We retained responsibility for clinical development programs for Fintepla, including completion of an additional Phase 3 trial (Study 3) to expand the countries to include Japan, amongst others, where Fintepla for the treatment of Dravet syndrome has been evaluated. We expect to include Study 3 as the pivotal study in our planned submission of a Japanese New Drug Application (J-NDA) in the second half of 2021.

Lennox-Gastaut Syndrome

In February 2020, we reported positive top-line results from our Phase 3 multicenter, global LGS trial (Study 1601), a double-blind, placebo-controlled study to assess the safety, tolerability and efficacy of Fintepla when added to a patient’s current anti-epileptic regimen. Study 1601 included a total of 263 patients between the ages of 2 and 35 years whose seizures were uncontrolled while on one or more anti-epileptic drugs. The trial met its primary objective of demonstrating that Fintepla at a dose of 0.7 mg/kg/day was superior to placebo in reducing the frequency of drop seizures and demonstrated statistically significant improvements versus placebo in key secondary efficacy measures, including proportion of patients with a clinically meaningful reduction in drop seizure frequency. We have completed all required studies to support a supplemental New Drug Application (sNDA) in the U.S., and compilation of data package is ongoing with anticipated filing of sNDA in the third quarter of 2021. In Europe, we anticipate submitting a Marketing Authorization Application with European Medicines Agency in the fourth quarter of 2021.

Other Potential Indications

In addition to Dravet syndrome and LGS, we are evaluating the treatment potential of Fintepla in other serious, treatment-resistant epileptic syndromes, including CDKL5 Deficiency Disorder (CDD), an infantile-onset genetic seizure disorder. New data presented from an investigator-initiated study in CDD at the American Epilepsy Society Annual Meeting in December 2020 suggests potential of Fintepla for the treatment of seizures associated with CDD. We anticipate initiating a Phase 3 study of Fintepla for the treatment of CDD in the second half of 2021.

ZOGENIX, INC. | Q1 2021 Form 10-Q | 21

MT1621 for Patients with TK2 Deficiency

As a result of our acquisition of Modis in September 2019, we became a party to the Exclusive License Agreement, by and between Modis and Columbia University, dated as of September 26, 2016 (the Columbia Agreement), related to MT1621. MT1621 is an investigational deoxynucleoside-combination substrate enhancement therapy in development for the treatment of TK2d, a rare, debilitating, and often fatal genetic mitochondrial DNA depletion disease that primarily affects infants and children and for which there are currently no approved therapies.

In April 2020, we held an End-of-Phase 2 meeting with the FDA and in June 2020, we met with the FDA to discuss chemistry, manufacturing, and controls (CMC) for MT1621. In the meetings, the FDA outlined the additional clinical and non-clinical information needed for an NDA submission. Based on the feedback, we expect availability of all required data by end of 2021 to support an NDA submission and anticipate submission of an NDA in the first half of 2022. In addition, we are conducting a Phase 1 pharmacokinetic (PK) study in renal impairment, as recommended by the FDA, to provide dosing recommendations in the setting of impaired renal function and include the results in the NDA submission. The FDA also concurred with our proposed CMC plan for the prospective NDA submission.

Preclinical Pipeline

Tevard Gene Therapy Collaboration for Genetic Epilepsies

In December 2020, we entered into a collaboration with Tevard Biosciences, Inc. (Tevard) for the research, development and commercialization of gene therapies for the treatment of Dravet syndrome and other epilepsy disorders. The collaboration is at the research and discovery stage and will leverage Tevard’s novel t-RNA-based technology to treat genetic disorders not amenable to traditional types of gene therapies, such as Dravet Syndrome.

Business Update Regarding the COVID-19 Pandemic

The current COVID-19 worldwide pandemic has presented substantial public health and economic challenges and is affecting our employees, patients and their families and caregivers, communities and business operations, as well as the U.S. and global economies and financial markets. International and U.S. governmental authorities in impacted regions are taking actions in an effort to slow the spread of COVID-19, including issuing varying forms of “stay-at-home” orders, and restricting business functions outside of one’s home. In response, we closed our offices for all but the most essential activities and have implemented a policy allowing all employees to work from home across all locations, following the guidelines or directives issued by federal, state and local government agencies in the U.S. as well as the U.K. government.

We commenced the commercial launch of Fintepla in the United States in July 2020 and in Germany in February 2021. Our commercialization efforts will need to navigate through the operational restrictions imposed on our sales force from quarantines, travel restrictions and bans and other governmental and healthcare restrictions related to COVID-19. As a result of these restrictions, until very recently, our sales force has not been able to conduct in-person interactions with physicians and healthcare providers and are largely restricted to primarily conducting educational and promotional activities for Fintepla virtually, which may impact our ability to market Fintepla. In addition, Fintepla is being launched through our Fintepla REMS program in the U.S. and a controlled access program in Europe, with each program requiring patients to obtain echocardiograms during this pandemic.

To date, we have been able to continue to supply Fintepla and MT1621 to our patients currently enrolled in our clinical trials and do not currently anticipate any interruptions in supply. Any delays in the completion of our clinical trials and any disruption in our supply chain could have a material adverse effect on our business, results of operations and financial condition. The full extent to which the COVID-19 pandemic will directly or indirectly impact our business, results of operations and financial condition, will depend on future developments that are highly uncertain, including as a result of new information that may emerge concerning COVID-19 and the actions taken to contain it or treat COVID-19, as well as the economic impact on local, regional, national and international markets.

Critical Accounting Policies and Estimates

The preparation of our unaudited condensed consolidated financial statements in accordance with GAAP requires that we make estimates and assumptions that affect the reported amounts of assets, liabilities, expenses and related disclosures. We evaluate our estimates and assumptions on an ongoing basis. Our estimates are based

ZOGENIX, INC. | Q1 2021 Form 10-Q | 22

on historical experience and various other assumptions that we believe to be reasonable under the circumstances. Actual results could differ from those estimates. Our critical accounting policies are discussed in Part II, Item 7, “Management's Discussion and Analysis of Financial Condition and Results of Operations” section of our 2020 Form 10-K. There have been no material changes during the three months ended March 31, 2021 to the critical accounting policies previously disclosed in that report.

Recent Accounting Pronouncements

For information with respect to recent accounting pronouncements that are of significance or potential significance to us, see Note 2, Accounting Policies to the condensed consolidated financial statements in Part I, Item 1 of this Quarterly Report on Form 10-Q.

Results of Operations

Comparison of Three Months Ended March 31, 2021 and 2020

The following table summarizes our total revenues for the periods indicated:

Revenues

	Three Months Ended March 31,
(in thousands)	2021		2020		Change
Net product sales	$	12,349	$	—	$	12,349
Collaboration revenue	1,335		1,249		86
Total revenues	$	13,684	$	1,249	$	12,435

Net Product Sales

For the three months ended March 31, 2021, total net product sales generated from Fintepla was $12.3 million, and consisted of $11.3 million derived in the United States and $1.0 million derived in Germany. Fintepla was approved by the FDA in June 2020 and marketing authorization was granted by the EMA in December 2020.

Collaboration Revenue

Collaboration revenue was flat for the three months ended March 31, 2021 as compared to the same period in 2020 as we conducted Study 3 to expand the countries where Fintepla has been evaluated to include Japan in fulfillment of our performance obligations under the collaboration arrangement. We anticipate Study 3 will be the pivotal study included in our planned submission of a J-NDA, expected to occur in the second half of 2021.

Cost of Product Sales (Excluding Amortization of Intangible Asset)

Cost of product sales (excluding amortization of intangible asset) includes the cost of producing and distributing inventories that are related to product revenues during the respective period (including salary-related and stock-based compensation expenses for employees involved with production and distribution, freight and indirect overhead costs) and third-party royalties payable on our net product revenues. Cost of product sales may also include costs related to excess or obsolete inventory adjustment charges, abnormal costs, unabsorbed manufacturing and overhead costs, and manufacturing variances.

During the three months ended March 31, 2021, cost of product sales primarily consisted of royalties payable on net product sales of Fintepla under a license agreement and labeling and packaging costs. Substantially all the cost of product sold during the three months ended March 31, 2021 had a zero-cost basis. Prior to receiving FDA approval for Fintepla, we recorded all manufacturing product costs as research and development expense. We expect our inventory with zero-cost basis will be depleted by the end of 2021 and expect cost of product sales to increase as a percentage of net sales in future periods as we produce and then sell inventory that reflects the full cost of manufacturing.

ZOGENIX, INC. | Q1 2021 Form 10-Q | 23

Research and Development Expenses

	Three Months Ended March 31,
(in thousands)	2021		2020		Change
Research and development	$	30,969	$	33,240	$	(2,271)

Research and development (R&D) expenses consist of expenses incurred in developing, testing and seeking marketing approval of our product candidates, including: payments made to third-party clinical research organizations (CROs) and investigational sites, which conduct our clinical trials on our behalf, and consultants; expenses associated with regulatory submissions, pre-clinical development and clinical trials; payments to third-party manufacturers, which produce our active pharmaceutical ingredient and finished product; pre-launch inventory, personnel related expenses, such as salaries, benefits, travel and other related expenses, including stock-based compensation; and facility, maintenance, depreciation and other related expenses.

For each of our R&D programs, we incur both external and internal costs. External costs include clinical and non-clinical activities performed by CROs, lab services, purchases of product candidate materials and manufacturing development costs. We track external R&D expenses for each of our key development programs. We have not tracked internal costs on a program-by-program basis because our R&D employees and infrastructure resources are utilized across our product candidate development programs.

The table below sets forth components of our R&D expenses for the periods presented.

	Three Months Ended March 31,
(in thousands)	2021		2020		Change
Fintepla for Dravet syndrome	$	4,515	$	7,311	$	(2,796)
Fintepla for LGS	7,834		7,943		(109)
MT1621	5,997		1,652		4,345
Tevard gene-therapy program for Dravet syndrome	786		—		786
Other(1)	177		797		(620)
Total external costs	19,309		17,703		1,606
Internal costs	11,660		15,537		(3,877)
Total	$	30,969	$	33,240	$	(2,271)

————————————

(1)Other external costs include early-phase exploratory research programs.

In October 2014, we acquired worldwide development and commercialization rights to Fintepla from the acquisition of Brabant and have since incurred significant expenditures related to conducting clinical trials of Fintepla. R&D expenses related to Fintepla for Dravet syndrome decreased by $2.8 million for the three months ended March 31, 2021 compared to the same period in 2020 primarily due to the wind-down of clinical activities related to our Phase 3 trials Study 1 and Study 1504, partially offset by costs incurred to conduct a Phase 3 clinical trial (Study 3) to support a J-NDA submission in Japan. R&D expenses related to MT1621 increased by $4.3 million in the same year-over-year periods as we continue to advance the MT1621 development program, including work related to chemistry, manufacturing, and controls process requirements. Internal costs for research and development activities decreased by $3.9 million for the three months ended March 31, 2021 compared to the same period in 2020 as our medical affairs function subsequent to regulatory approval of Fintepla is classified as selling, general and administrative expenses.

Selling, General and Administrative Expenses

	Three Months Ended March 31,
(in thousands)	2021		2020		Change
Selling, general and administrative	$	31,272	$	21,318	$	9,954

Selling, general and administrative expenses consist primarily of salaries and related costs for our personnel, including stock-based compensation, market research expenses for our product and product candidates that are in development and marketing expenses to support our commercial launch efforts, executive, finance, accounting,

ZOGENIX, INC. | Q1 2021 Form 10-Q | 24

business development and internal support functions, facility-related costs and consulting fees, in each case not otherwise included in R&D expenses.

Selling, general and administrative expenses increased by $10.0 million for the three months ended March 31, 2021 compared to the same period in 2020 and was primarily attributable to increases in personnel-related costs as we build out our specialized and focused commercial teams in support of our Fintepla product launches in the U.S. and Europe and headcount additions in general and administrative to support our commercial team. In addition, commercial spending related to market research, strategic and logistic planning for our product launch also contributed to the increase. The remainder of the increase was attributable to higher insurance premium costs and an increase in utilization of professional services, as well as infrastructure and facilities-related costs.

Amortization of Intangible Asset

	Three Months Ended March 31,
(in thousands)	2021		2020		Change
Amortization of intangible asset	$	1,971	$	—	$	1,971

Our intangible asset consists of worldwide development, commercialization and related intellectual property rights including patents and licenses for our product, Fintepla, which we began to amortize after receipt of FDA approval over its estimated useful life of 13 years on a straight-line basis.

Acquired In-Process Research and Development Costs (IPR&D)

	Three Months Ended March 31,
(in thousands)	2021		2020		Change
Acquired IPR&D	$	—	$	1,500	$	(1,500)

For the three months ended March 31, 2020, we incurred $1.5 million in option maintenance fees for the right to license a preclinical development program to identify and develop potential next-generation gene therapies for Dravet syndrome from Tevard. We exercised the option to opt-in the Dravet syndrome program by entering into a collaboration, option and license agreement with Tevard in December 2020. Costs related to funding this program subsequent to the exercise of our option are recorded within research and development expense.

Change in Fair Value of Contingent Consideration

	Three Months Ended March 31,
(in thousands)	2021		2020
Change in fair value of contingent consideration	$	600	$	(7,900)

The contingent consideration liability relates to milestone payments under an existing agreement in connection with our prior acquisition of Fintepla. At each reporting period, the estimated fair value of the liability is determined by applying the income approach which utilizes variable inputs, such as the probability of success for achieving regulatory and sales-based milestones, anticipated future cash flows, risk-free adjusted discount rates, and nonperformance risk. Any change in the fair value is recorded as contingent consideration (income) expense.

For the three months ended March 31, 2021, the $0.6 million increase to the estimated fair value of our contingent consideration liability reflects the interest component of contingent consideration related to the passage of time.

For the three months ended March 31, 2020, the $7.9 million decrease in fair value of our contingent consideration was primarily due to changes to our probability-weighted estimates for achieving regulatory/commercial milestones and the use of a higher discount rate to reflect an increase in credit-adjusted interest rates.

ZOGENIX, INC. | Q1 2021 Form 10-Q | 25

Other Income (Expense)

	Three Months Ended March 31,
(in thousands)	2021		2020
Other income (expense):
Interest income	308		1,088
Interest expense	(3,737)		—
Other income, net	(397)		20,021
Total	$	(3,826)	$	21,109

For the three months ended March 31, 2020, other income included a $19.7 million claim submitted under UK’s R&D Tax Relief Scheme for eligible R&D expenditures incurred in tax years 2017 and 2018.

Liquidity and Capital Resources

Excluding gains from two discrete business divestitures, we have incurred significant net losses and negative cash flows from operating activities since inception. As of March 31, 2021, our accumulated deficit was $1.4 billion. We expect to continue to incur significant operating losses and negative cash flows from operations to support the marketing and commercialization of Fintepla for Dravet syndrome as well as continuing to advance our clinical programs. Additionally, we are obligated to make future milestone payments that are contingent upon the successful achievement of certain substantive development, regulatory and sales-based milestone events related to Fintepla and MT1621. We recently launched Fintepla in the U.S. and Europe and generate revenue from product sales. We also generate collaboration revenue from our collaborative arrangement with Nippon Shinyaku Co., Ltd. We expect to continue to incur significant operating losses and negative cash flows from operations as we begin to commercialize Fintepla and advance our product candidates through development in the short-term. Historically, we have relied primarily on the proceeds from equity and convertible debt offerings to finance our operations.

We are party to an at-the-market sales agreement (ATM Sales Agreement) with Cantor Fitzgerald & Co. (Cantor), pursuant to which Cantor has agreed to act as sales agent in connection with the issuance and sale of up to $200.0 million in gross aggregate proceeds of our common stock from time to time pursuant to the ATM Sales Agreement and our automatic “shelf” registration statement on Form S-3 registering the offering filed in June 2020. For the three months ended March 31, 2021, there were no sales of common stock under the ATM Sales Agreement and as of March 31, 2021, we have remaining capacity to sell up to approximately $195.0 million of common stock under the ATM Sales Agreement.

In September and October 2020, we issued $230.0 million aggregate principal amount of 2.75% convertible senior Notes due 2027 (Notes) and realized net proceeds of $222.5 million. The Notes are governed by an indenture (Indenture), dated as of September 28, 2020, between Zogenix and U.S. Bank National Association, as trustee. Under the Indenture, the Notes are senior, unsecured obligations of Zogenix, are equal in right of payment with its future senior, unsecured indebtedness of Zogenix, and structurally subordinated to all indebtedness and liabilities of its subsidiaries. Interest is payable semi-annually in arrears on April 1 and October 1 of each year, beginning on April 1, 2021 at a rate of 2.75% per year. The Notes mature on October 1, 2027, unless earlier repurchased, redeemed or converted. The Indenture contains customary terms and covenants and may become due and payable upon the occurrence of an event of default, but does not contain any financial covenants. As of March 31, 2021, we were in compliance with all covenants under the Indenture.

The Notes are convertible, subject to certain conditions described below, into shares of our common stock at an initial conversion rate of 41.1794 shares per $1,000 principal amount of the Notes, which represents an initial conversion price of approximately $24.28 per share, subject to adjustments upon the occurrence of certain events. Certain corporate events described in the Indenture may increase the conversion rate for holders who elect to convert their Notes in connection with such corporate event should they occur. We may also choose to repurchase outstanding Notes through open-market transactions, including through Rule 10b5-1 trading plan to facilitate open-market repurchases, or otherwise, from time to time.

Holders may convert the Notes in multiples of $1,000 principal amount at any time prior to October 1, 2027, but only in the following circumstances:

ZOGENIX, INC. | Q1 2021 Form 10-Q | 26

•during any calendar quarter ending after December 31, 2020, if our closing stock price exceeds 130% of the conversion price on each of at least 20 trading days of the last 30 consecutive trading days of the immediately preceding calendar quarter;

•during the five consecutive business day period after any 10 consecutive trading day period in which the Notes’ trading price is less than 98% of the product of our closing stock price times the conversion rate; or

•the occurrence of certain corporate events, such as a change of control, merger, default or liquidation.

During the three months ended March 31, 2021, the closing price of our common stock did not exceed 130% of the applicable conversion price of our Notes on at least 20 of the last 30 consecutive trading days of the quarter. Furthermore, no other conditions allowing holders of the Notes to convert have been met as of March 31, 2021. Therefore, the Notes are not convertible for the three months ending June 30, 2021.

As of March 31, 2021, our cash, cash equivalents and marketable securities totaled $435.2 million. We believe our existing capital resources are sufficient to meet our projected operating requirements for at least the next 12 months. Our principal uses of cash are research and development expenses, selling, general and administrative expenses and other working capital requirements. Our future funding requirements will depend on many factors, including, but not limited to:

•our ability to generate sales of Fintepla for the treatment of seizures associated with Dravet syndrome;

•the costs of establishing or outsourcing sales, marketing and distribution capabilities for Fintepla for the treatment of Dravet syndrome and, should we elect to do so, for any of our other product candidates;

•the rate of progress and cost of our clinical trials and other product development programs for Fintepla, MT1621 and our other product candidates and any other product candidates that we may develop, in-license or acquire;

•the timing of regulatory approval of our product candidates and the commercial success of Fintepla and any other approved products;

•the costs of filing, prosecuting, defending and enforcing any patent claims and other intellectual property rights associated with Fintepla, MT1621 and any of our other product candidates;

•the timing and amounts of the milestone or other payments we must make related to Fintepla and MT1621;

•the costs, terms and timing of completion of outsourced commercial manufacturing supply arrangements for any product candidate;

•the effect of competing technological and market developments; and

•any delays and cost increases that result from the COVID-19 pandemic.

Until we can generate a sufficient amount of revenue to finance our cash requirements, if ever, we may need to continue to rely on additional financing to achieve our business objectives. However, we may not be able to secure such financing in a timely manner or on favorable terms, if at all, and this risk could be exacerbated by the impact of COVID-19 on global economic conditions. If future funds are raised through issuance of equity or debt securities, these securities may have rights, preferences and privileges senior to those of our existing stockholders. If we raise additional funds through collaboration, licensing or other similar arrangements, it may be necessary to relinquish valuable rights to our potential products or proprietary technologies, or grant licenses on terms that are not favorable to us. Without additional funds at the time we need such funding, we may be forced to delay, scale back or eliminate some of our research and development activities, our commercialization efforts, or other operations and potentially delay product development in an effort to provide sufficient funds to continue our operations. If any of these events occurs, our ability to achieve the development and commercialization goals could be adversely affected.

ZOGENIX, INC. | Q1 2021 Form 10-Q | 27

The following table presents selected information from our statements of cash flows (in thousands):

	Three Months Ended March 31,
	2021		2020
Cash and cash equivalents, beginning of the period	$	166,916	$	62,070
Net cash used in operating activities	(53,858)		(52,491)
Net (used in) provided by investing activities	(10,851)		37,217
Net (used in) provided by financing activities	(15,890)		223,179
Net (decrease) increase in cash and cash equivalents	(80,599)		207,905
Cash and cash equivalents, end of the period	$	86,317	$	269,975

Operating Activities

For the three months ended March 31, 2021, net cash used in operating activities of $53.9 million was primarily attributable to a net loss of $55.6 million and net changes in operating assets and liabilities of $11.6 million, offset by an aggregate of $13.4 million of non-cash charges, net. Non-cash items included stock-based compensation expense of $8.1 million, amortization of debt discount and issuance costs of $2.1 million related to our convertible senior notes and intangible asset amortization of $2.0 million. Net changes in operating assets and liabilities totaled an outflow of $11.6 million, principally due to decreases in accrued liabilities including annual bonus payout and increases in accounts receivable and inventory related to Fintepla commercial sales. This cash outflow was partially offset by cash received of $3.0 million for the final installments due under the Shinyaku Agreement wherein $20.0 million in fixed consideration was scheduled to be paid within the first two years of the date of the agreement.

For the three months ended March 31, 2020, net cash used in operating activities of $52.5 million was primarily attributable to a net loss of $25.8 million and a $19.7 million increase to other receivable to record approved claims under the U.K R&D Tax Credit Relief Scheme.

Investing Activities

For the three months ended March 31, 2021, net cash used in investing activities of $10.9 million was attributable to net marketable securities purchases.

For the three months ended March 31, 2020, net cash provided by investing activities of $37.2 million was primarily attributable to net marketable securities maturities of $38.9 million.

Financing Activities

For the three months ended March 31, 2021, net cash used in financing activities of $15.9 million consisted of a $15.0 million contingent consideration payment related to regulatory approval of Fintepla in Europe and cash used to remit withholding taxes of $0.9 million related to the vesting of restricted stock units that were net share-settled by us to cover the required withholding taxes.

For the three months ended March 31, 2020, net cash provided by financing activities of $223.2 million primarily consisted of net proceeds realized from the issuance of 9.8 million shares of our common stock in a public offering and $1.5 million in net proceeds received from the issuance of common stock pursuant to our equity incentive plans.

Contractual Obligations

There were no material changes outside the ordinary course of our business during the three months ended March 31, 2021 to the information regarding our contractual obligations that was disclosed in Management’s Discussion and Analysis of Financial Condition and Results of Operations included in our 2020 Form 10-K.

Off-Balance Sheet Arrangements

As of March 31, 2021, we did not have any off-balance sheet arrangements, as defined in Item 303(a)(4)(ii) of Regulation S-K.

ZOGENIX, INC. | Q1 2021 Form 10-Q | 28

Item 3. Quantitative and Qualitative Disclosures About Market Risk

For quantitative and qualitative disclosures about market risk, see Item 7A, Quantitative and Qualitative Disclosures About Market Risk, of our 2020 Form 10-K. Our exposures to market risk have not changed materially since December 31, 2020.

Item 4. Controls and Procedures

Conclusions Regarding the Effectiveness of Disclosure Controls and Procedures

We maintain disclosure controls and procedures that are designed to ensure that information required to be disclosed in our Exchange Act reports is recorded, processed, summarized and reported within the timelines specified in the Securities and Exchange Commission’s rules and forms, and that such information is accumulated and communicated to our management, including our Chief Executive Officer and Chief Financial Officer, as appropriate, to allow timely decisions regarding required disclosure. In designing and evaluating the disclosure controls and procedures, management recognized that any controls and procedures, no matter how well designed and operated, can only provide reasonable assurance of achieving the desired control objectives, and in reaching a reasonable level of assurance, management necessarily was required to apply its judgment in evaluating the cost-benefit relationship of possible controls and procedures.

As required by SEC Rule 13a-15(b), we carried out an evaluation, under the supervision and with the participation of our management, including our Chief Executive Officer and Chief Financial Officer, of the effectiveness of the design and operation of our disclosure controls and procedures as of the end of the period covered by this report. Based on the foregoing, our Chief Executive Officer and Chief Financial Officer concluded that our disclosure controls and procedures were effective as of March 31, 2021 at the reasonable assurance level.

Changes in Disclosure Controls and Procedures

There were no changes in our internal control over financial reporting during the three months ended March 31, 2021 that have materially affected, or are reasonably likely to materially affect, our internal control over financial reporting.

ZOGENIX, INC. | Q1 2021 Form 10-Q | 29

PART II – OTHER INFORMATION

Item 1. Legal Proceedings

From time to time, we may become involved in various legal proceedings and claims that arise in the ordinary course of business. We are not currently involved in any material legal proceedings. Such matters are subject to uncertainty and there can be no assurance that such legal proceedings will not have a material adverse effect on our business, results of operations, financial position or cash flows.

Item 1A. Risk Factors

There have been no material changes in our risk factors from those disclosed in Part I, Item 1A of our 2020 Form 10-K.

Item 2. Unregistered Sales of Equity Securities and Use of Proceeds

Unregistered Sales of Equity Securities

None.

Use of Proceeds

Not applicable.

Item 3. Defaults Upon Senior Securities

None.

Item 4. Mine Safety Disclosures

Not applicable.

Item 5. Other Information

None.

ZOGENIX, INC. | Q1 2021 Form 10-Q | 30

Item 6. Exhibits

EXHIBIT INDEX

Exhibit Number	Exhibit Description
3.1(1)	Fifth Amended and Restated Certificate of Incorporation of the Registrant
3.2(2)	Certificate of Amendment of Fifth Amended and Restated Certificate of Incorporation of the Registrant
3.3(3)	Certificate of Amendment of Fifth Amended and Restated Certificate of Incorporation of the Registrant
3.4(4)	Certificate of Amendment of Fifth Amended and Restated Certificate of Incorporation of the Registrant
3.5(1)	Fifth Amended and Restated Certificate of Incorporation of the Registrant
4.1(5)	Form of the Registrant’s Common Stock Certificate
4.2(6)	Warrant dated July 18, 2011 issued by the Registrant to Healthcare Royalty Partners (formerly Cowen Healthcare Royalty Partners II, L.P.)
4.3(7)	Indenture, dated as of September 28, 2020, between Zogenix, Inc. and U.S. Bank National Association, as trustee
4.4(7)	Form of Global Note representing the 2.75% Convertible Senior Notes due 2027 (included as Exhibit A to Exhibit 4.3)
31.1*	Certification of Chief Executive Officer pursuant to Section 302 of the Public Company Accounting Reform and Investor Protection Act of 2002 (18 U.S.C. §1350, as adopted)
31.2*	Certification of Chief Financial Officer pursuant to Section 302 of the Public Company Accounting Reform and Investor Protection Act of 2002 (18 U.S.C. §1350, as adopted)
32.1**	Certification of Chief Executive Officer pursuant to Section 906 of the Public Company Accounting Reform and Investor Protection Act of 2002 (18 U.S.C. §1350, as adopted)
32.2**	Certification of Chief Financial Officer pursuant to Section 906 of the Public Company Accounting Reform and Investor Protection Act of 2002 (18 U.S.C. §1350, as adopted)
101*	Inline XBRL Document Set for the condensed consolidated financial statements and accompanying notes in Part I, Item 1, “Financial Statements” of this Quarterly Report on Form 10-Q.
104*	Inline XBRL for the cover page of this Quarterly Report on Form 10-Q, included in the Exhibit 101 Inline XBRL Document Set.

____________________

(1)Incorporated by reference to Amendment No. 2 to the Registrant’s Registration Statement on Form S-1 filed on October 27, 2010.

(2)Incorporated by reference to the Registrant’s Quarterly Report on Form 10-Q filed on November 8, 2012.

(3)Incorporated by reference to the Registrant’s Quarterly Report on Form 10-Q filed on August 10, 2015.

(4)Incorporated by reference to the Registrant’s Quarterly Report on Form 10-Q filed on August 6, 2019.

(5)Incorporated by reference to Amendment No. 3 to the Registrant’s Registration Statement on Form S-1 filed on November 4, 2010.

(6)Incorporated by reference to the Registrant’s Quarterly Report on Form 10-Q filed on August 12, 2011.

*Filed herewith.

**These certifications are being furnished solely to accompany this quarterly report pursuant to 18 U.S.C. Section 1350, and are not being filed for purposes of Section 18 of the Securities Exchange Act of 1934 and are not subject to the liability of that section. These certifications are not to be incorporated by reference into any filing of Zogenix, Inc., whether made before or after the date hereof, regardless of any general incorporation language in such filing herewith.

ZOGENIX, INC. | Q1 2021 Form 10-Q | 31

SIGNATURES

Pursuant to the requirements of the Securities Exchange Act of 1934, as amended, the Registrant has duly caused this report to be signed on its behalf by the undersigned, thereunto duly authorized.

 

			ZOGENIX, INC.
Date:	May 6, 2021	By:	/s/ Stephen J. Farr
			President and Chief Executive Officer
			(Principal Executive Officer)
Date:	May 6, 2021	By:	/s/ Michael P. Smith
			Executive Vice President, Chief Financial Officer and Treasurer
			(Principal Financial and Accounting Officer)

EX-31.1

Exhibit 31.1

CERTIFICATION OF CHIEF EXECUTIVE OFFICER PURSUANT TO

SECTION 302 OF THE SARBANES-OXLEY ACT OF 2002

I, Stephen J. Farr, certify that:

1.I have reviewed this Quarterly Report on Form 10-Q of Zogenix Inc.;

2.Based on my knowledge, this report does not contain any untrue statement of a material fact or omit to state a material fact necessary to make the statements made, in light of the circumstances under which such statements were made, not misleading with respect to the period covered by this report;

3.Based on my knowledge, the consolidated financial statements, and other financial information included in this report, fairly present in all material respects the financial condition, results of operations and cash flows of the registrant as of, and for, the periods presented in this report;

4.The registrant’s other certifying officer(s) and I are responsible for establishing and maintaining disclosure controls and procedures (as defined in Exchange Act Rules 13a-15(e) and 15d-15(e)) and internal control over financial reporting (as defined in Exchange Act Rules 13a-15(f) and 15d-15(f)) for the registrant and have:

a.Designed such disclosure controls and procedures, or caused such disclosure controls and procedures to be designed under our supervision, to ensure that material information relating to the registrant, including its consolidated subsidiaries, is made known to us by others within those entities, particularly during the period in which this report is being prepared;

b.Designed such internal control over financial reporting, or caused such internal control over financial reporting to be designed under our supervision, to provide reasonable assurance regarding the reliability of financial reporting and the preparation of financial statements for external purposes in accordance with generally accepted accounting principles;

c.Evaluated the effectiveness of the registrant’s disclosure controls and procedures and presented in this report our conclusions about the effectiveness of the disclosure controls and procedures, as of the end of the period covered by this report based on such evaluation; and

d.Disclosed in this report any change in the registrant’s internal control over financial reporting that occurred during the registrant’s most recent fiscal quarter (the registrant’s fourth fiscal quarter in the case of an annual report) that has materially affected, or is reasonably likely to materially affect, the registrant’s internal control over financial reporting; and

5.The registrant’s other certifying officer(s) and I have disclosed, based on our most recent evaluation of internal control over financial reporting, to the registrant’s auditors and the audit committee of the registrant’s board of directors (or persons performing the equivalent functions):

a.All significant deficiencies and material weaknesses in the design or operation of internal control over financial reporting which are reasonably likely to adversely affect the registrant’s ability to record, process, summarize and report financial information; and

b.Any fraud, whether or not material, that involves management or other employees who have a significant role in the registrant’s internal control over financial reporting.

Date: May 6, 2021	By:	/s/ Stephen J. Farr
		Stephen J. Farr
		President and Chief Executive Officer
		(Principal Executive Officer)

EX-31.2

Exhibit 31.2

CERTIFICATION OF CHIEF FINANCIAL OFFICER PURSUANT TO

SECTION 302 OF THE SARBANES-OXLEY ACT OF 2002

I, Michael P. Smith, certify that:

1.I have reviewed this Quarterly Report on Form 10-Q of Zogenix, Inc.;

2.Based on my knowledge, this report does not contain any untrue statement of a material fact or omit to state a material fact necessary to make the statements made, in light of the circumstances under which such statements were made, not misleading with respect to the period covered by this report;

3.Based on my knowledge, the consolidated financial statements, and other financial information included in this report, fairly present in all material respects the financial condition, results of operations and cash flows of the registrant as of, and for, the periods presented in this report;

4.The registrant’s other certifying officer(s) and I are responsible for establishing and maintaining disclosure controls and procedures (as defined in Exchange Act Rules 13a-15(e) and 15d-15(e)) and internal control over financial reporting (as defined in Exchange Act Rules 13a-15(f) and 15d-15(f)) for the registrant and have:

a.Designed such disclosure controls and procedures, or caused such disclosure controls and procedures to be designed under our supervision, to ensure that material information relating to the registrant, including its consolidated subsidiaries, is made known to us by others within those entities, particularly during the period in which this report is being prepared;

b.Designed such internal control over financial reporting, or caused such internal control over financial reporting to be designed under our supervision, to provide reasonable assurance regarding the reliability of financial reporting and the preparation of financial statements for external purposes in accordance with generally accepted accounting principles;

c.Evaluated the effectiveness of the registrant’s disclosure controls and procedures and presented in this report our conclusions about the effectiveness of the disclosure controls and procedures, as of the end of the period covered by this report based on such evaluation; and

d.Disclosed in this report any change in the registrant’s internal control over financial reporting that occurred during the registrant’s most recent fiscal quarter (the registrant’s fourth fiscal quarter in the case of an annual report) that has materially affected, or is reasonably likely to materially affect, the registrant’s internal control over financial reporting; and

5.The registrant’s other certifying officer(s) and I have disclosed, based on our most recent evaluation of internal control over financial reporting, to the registrant’s auditors and the audit committee of the registrant’s board of directors (or persons performing the equivalent functions):

a.All significant deficiencies and material weaknesses in the design or operation of internal control over financial reporting which are reasonably likely to adversely affect the registrant’s ability to record, process, summarize and report financial information; and

b.Any fraud, whether or not material, that involves management or other employees who have a significant role in the registrant’s internal control over financial reporting.

Date: May 6, 2021	By:	/s/ Michael P. Smith
		Michael P. Smith
		Executive Vice President, Chief Financial Officer and Treasurer
		(Principal Financial Officer)

EX-32.1

Exhibit 32.1

CERTIFICATION

Pursuant to Section 906 of the Sarbanes-Oxley Act of 2002

(Subsections (a) and (b) of Section 1350, Chapter 63 of Title 18, United States Code)

In connection with the Quarterly Report on Form 10-Q of Zogenix, Inc. (the “Company”) for the period ended March 31, 2021, as filed with the Securities and Exchange Commission on the date hereof (the “Report”), I, Stephen J. Farr, as Chief Executive Officer of the Company, certify, pursuant to 18 U.S.C. Section 1350, as adopted pursuant to Section 906 of the Sarbanes-Oxley Act of 2002, that to my knowledge:

1.The Report fully complies with the requirements of Section 13(a) or 15(d) of the Securities Exchange Act of 1934; and

2.The information contained in the Report fairly presents, in all material respects, the financial condition and results of operations of the Company.

Date: May 6, 2021	By:	/s/ Stephen J. Farr
		Stephen J. Farr
		President and Chief Executive Officer
		(Principal Executive Officer)

The foregoing certification is being furnished solely to accompany the Report pursuant to 18 U.S.C. § 1350, and is not being filed for purposes of Section 18 of the Securities Exchange Act of 1934, as amended, and is not to be incorporated by reference into any filing of the Company, whether made before or after the date hereof, regardless of any general incorporation language in such filing. A signed original of this written statement required by Section 906 has been provided to the Company and will be retained by the Company and furnished to the Securities and Exchange Commission or its staff upon request.

EX-32.2

Exhibit 32.2

CERTIFICATION

Pursuant to Section 906 of the Sarbanes-Oxley Act of 2002

(Subsections (a) and (b) of Section 1350, Chapter 63 of Title 18, United States Code)

In connection with the Quarterly Report on Form 10-Q of Zogenix Inc. (the “Company”) for the period ended March 31, 2021, as filed with the Securities and Exchange Commission on the date hereof (the “Report”), I, Michael P. Smith, as Chief Financial Officer of the Company, certify, pursuant to 18 U.S.C. Section 1350, as adopted pursuant to Section 906 of the Sarbanes-Oxley Act of 2002, that to my knowledge:

1.The Report fully complies with the requirements of Section 13(a) or 15(d) of the Securities Exchange Act of 1934; and

2.The information contained in the Report fairly presents, in all material respects, the financial condition and results of operations of the Company.

Date: May 6, 2021	By:	/s/ Michael P. Smith
		Michael P. Smith
		Executive Vice President, Chief Financial Officer and Treasurer

The foregoing certification is being furnished solely to accompany the Report pursuant to 18 U.S.C. § 1350, and is not being filed for purposes of Section 18 of the Securities Exchange Act of 1934, as amended, and is not to be incorporated by reference into any filing of the Company, whether made before or after the date hereof, regardless of any general incorporation language in such filing. A signed original of this written statement required by Section 906 has been provided to the Company and will be retained by the Company and furnished to the Securities and Exchange Commission or its staff upon request.

XML

Cover Page - shares	3 Months Ended
	Mar. 31, 2021	Apr. 30, 2021
Cover [Abstract]
Document type	10-Q
Document quarterly report	true
Document period end date	Mar. 31, 2021
Document transition report	false
Entity file number	001-34962
Entity registrant name	ZOGENIX, INC.
Entity incorporation, state or country code	DE
Entity tax identification number	20-5300780
Entity address, address line one	5959 Horton Street
Entity address, address line two	Suite 500
Entity address, city or town	Emeryville
Entity address, state or province	CA
Entity address, postal zip code	94608
City area code	510
Local phone number	550-8300
Title of 12(b) security	Common Stock, par value $0.001 per share
Trading symbol	ZGNX
Security exchange name	NASDAQ
Entity current reporting status	Yes
Entity interactive data current	Yes
Entity filer category	Large Accelerated Filer
Entity small business	false
Entity emerging growth company	false
Entity shell company	false
Entity common stock, shares outstanding		55,812,590
Entity central index key	0001375151
Amendment flag	false
Document fiscal year focus	2021
Document fiscal period focus	Q1
Current fiscal year end date	--12-31

XML

CONDENSED CONSOLIDATED BALANCE SHEETS (Unaudited) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Current assets:
Cash and cash equivalents	$ 86,317	$ 166,916
Marketable securities	348,905	338,193
Accounts receivable, net	6,119	3,824
Inventory	2,324	1,026
Prepaid expenses and other current assets	11,065	12,215
Total current assets	454,730	522,174
Property and equipment, net	8,377	8,724
Operating lease right-of-use assets	7,452	7,748
Intangible asset, net	96,587	98,558
Goodwill	6,234	6,234
Other non-current assets	7,584	7,692
Total assets	580,964	651,130
Current liabilities:
Accounts payable	11,964	11,945
Accrued and other current liabilities	30,749	54,964
Deferred revenue, current	5,297	5,318
Current portion of operating lease liabilities	1,621	1,688
Current portion of contingent consideration	8,900	8,800
Total current liabilities	58,531	82,715
Deferred revenue, noncurrent	5,664	5,479
Operating lease liabilities, net of current portion	9,937	10,314
Contingent consideration, net of current portion	34,100	33,600
Convertible senior notes	151,451	149,353
Total liabilities	259,683	281,461
Commitments and contingencies
Stockholders’ equity:
Preferred stock, $0.001 par value; 10,000 shares authorized; none issued and outstanding	0	0
Common stock and additional paid-in capital, $0.001 par value: 100,000 shares authorized; 55,813 and 55,736 shares issued and outstanding at March 31, 2021 and December 31, 2020, respectively	1,701,788	1,694,580
Accumulated deficit	(1,380,470)	(1,324,840)
Accumulated other comprehensive loss	(37)	(71)
Total stockholders’ equity	321,281	369,669
Total liabilities and stockholders’ equity	$ 580,964	$ 651,130

XML

CONDENSED CONSOLIDATED BALANCE SHEETS (Unaudited) (Parenthetical) - $ / shares	Mar. 31, 2021	Dec. 31, 2020
Statement of Financial Position [Abstract]
Preferred stock par value (usd per share)	$ 0.001	$ 0.001
Preferred stock authorized (shares)	10,000,000	10,000,000
Preferred stock issued (shares)	0	0
Preferred stock outstanding (shares)	0	0
Common stock par value (usd per share)	$ 0.001	$ 0.001
Common stock authorized (shares)	100,000,000	100,000,000
Common stock issued (shares)	55,813,000	55,736,000
Common stock outstanding (shares)	55,813,000	55,736,000

XML

CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS (Unaudited) - USD ($) shares in Thousands, $ in Thousands	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Income Statement [Abstract]
Net product sales	$ 12,349	$ 0
Collaboration revenue	1,335	1,249
Total revenues	13,684	1,249
Costs and expenses:
Cost of product sales (excluding amortization of intangible asset)	676	0
Research and development	30,969	33,240
Selling, general and administrative	31,272	21,318
Intangible asset amortization	1,971	0
Acquired in-process research and development costs	0	1,500
Change in fair value of contingent consideration	600	(7,900)
Total costs and expenses	65,488	48,158
Loss from operations	(51,804)	(46,909)
Interest income	308	1,088
Interest expense	(3,737)	0
Other (expense) income, net	(397)	20,021
Net loss	$ (55,630)	$ (25,800)
Net loss per share, basic and diluted
Net loss per share, basic and diluted (in dollars per share)	$ (1.00)	$ (0.54)
Weighted average number of shares used in the calculation of basic and diluted net loss per common share (in shares)	55,750	48,185

XML

CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE LOSS (Unaudited) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Statement of Comprehensive Income [Abstract]
Net loss	$ (55,630)	$ (25,800)
Other comprehensive (loss) income, net of tax:
Change in unrealized gains related to marketable securities	(112)	(172)
Foreign currency translation adjustments	146	5
Total other comprehensive income (loss)	34	(167)
Comprehensive loss	$ (55,596)	$ (25,967)

XML

CONDENSED CONSOLIDATED STATEMENTS OF STOCKHOLDERS’ EQUITY (Unaudited) - USD ($) shares in Thousands, $ in Thousands	Total	Shares of Common Stock	Common Stock and Additional Paid-in Capital	Accumulated Deficit	Accumulated Other Comprehensive (Loss) Income
Stockholders' Equity Beginning Balance at Dec. 31, 2019	$ 245,059		$ 1,360,137	$ (1,115,457)	$ 379
Stockholders' Equity - Beginning Balance (in shares) at Dec. 31, 2019		45,272
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net loss	(25,800)			(25,800)
Other comprehensive income (loss)	(167)				(167)
Issuance of common stock, net of offering costs	221,708		221,708
Issuance of common stock, net of offering costs (in shares)		9,798
Issuance of common stock under employee equity plans	3,882		3,882
Issuance of common stock under employee equity plans (in shares)		297
Shares repurchased to satisfy tax withholding obligation of vesting restricted stock units	(569)		(569)
Shares repurchased to satisfy tax withholding obligation of vesting restricted stock units (in shares)		(26)
Stock-based compensation	6,394		6,394
Stockholders' Equity Ending Balance at Mar. 31, 2020	450,507		1,591,552	(1,141,257)	212
Stockholders' Equity - Ending Balance (in shares) at Mar. 31, 2020		55,341
Stockholders' Equity Beginning Balance at Dec. 31, 2020	369,669		1,694,580	(1,324,840)	(71)
Stockholders' Equity - Beginning Balance (in shares) at Dec. 31, 2020		55,736
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net loss	(55,630)			(55,630)
Other comprehensive income (loss)	34				34
Issuance of common stock under employee equity plans	6		6
Issuance of common stock under employee equity plans (in shares)		120
Shares repurchased to satisfy tax withholding obligation of vesting restricted stock units	(896)		(896)
Shares repurchased to satisfy tax withholding obligation of vesting restricted stock units (in shares)		(43)
Stock-based compensation	8,098		8,098
Stockholders' Equity Ending Balance at Mar. 31, 2021	$ 321,281		$ 1,701,788	$ (1,380,470)	$ (37)
Stockholders' Equity - Ending Balance (in shares) at Mar. 31, 2021		55,813

XML

CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS (Unaudited) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Cash flows from operating activities:
Net loss	$ (55,630)	$ (25,800)
Adjustments to reconcile net loss to net cash used in operating activities
Stock-based compensation	8,098	6,394
Depreciation and amortization	2,365	357
Amortization of debt discount and issuance costs	2,098	0
Acquired in-process research and development expense	0	1,500
Change in fair value of contingent consideration	600	(7,900)
Other non-cash items, net	236	(38)
Changes in operating assets and liabilities:
Accounts receivable	(2,295)	0
Inventory	(1,298)	0
Prepaid expenses and other current assets	1,150	(20,463)
Other non-current assets	108	(405)
Accounts payable, accrued and other current liabilities	(9,010)	(4,435)
Operating lease liabilities	(444)	(452)
Deferred revenue	164	(1,249)
Net cash used in operating activities	(53,858)	(52,491)
Cash flows from investing activities:
Cash paid for in-process research and development asset	0	(1,500)
Purchases of marketable securities	(141,652)	(15,695)
Proceeds from sale and maturities of marketable securities	130,888	54,605
Purchases of property and equipment	(87)	(193)
Net cash (used in) provided by investing activities	(10,851)	37,217
Cash flows from financing activities:
Payment of contingent consideration	(15,000)	0
Proceeds from issuance of common stock under equity incentive plans	6	2,040
Payments of tax withholding obligation on vesting restricted stock units	(896)	(569)
Proceeds from issuance of common stock, net of issuance costs	0	221,708
Net cash (used in) provided by financing activities	(15,890)	223,179
Net (decrease) increase in cash and cash equivalents	(80,599)	207,905
Cash and cash equivalents, beginning of the period	166,916	62,070
Cash and cash equivalents, end of the period	86,317	269,975
Supplemental Disclosure of Non-Cash Investing and Financing Activities:
Right-of-use assets obtained in exchange for new operating lease liabilities	$ 0	$ 1,156

XML

Organization, Basis of Presentation and Liquidity

3 Months Ended

Mar. 31, 2021

Organization, Consolidation and Presentation of Financial Statements [Abstract]

Organization, Basis of Presentation and Liquidity

Organization, Basis of Presentation and Liquidity

Zogenix, Inc., and subsidiaries (also referred to as Zogenix, we, our or us) is a global biopharmaceutical company committed to developing and commercializing therapies with the potential to transform the lives of patients and their families living with rare diseases. Our first rare disease therapy, Fintepla (fenfluramine) oral solution, has been approved by the U.S. Food and Drug Administration (FDA) and the European Medicines Agency (EMA) for the treatment of seizures associated with Dravet syndrome, a rare, devastating, severe lifelong epilepsy. Fintepla is also currently under development in Japan. We also have two late-stage development programs underway: one for Fintepla for the treatment of seizures associated with Lennox-Gastaut syndrome (LGS), a rare childhood-onset epilepsy, and another for MT1621, an investigational novel substrate enhancement therapy for the treatment of TK2 deficiency, a rare genetic disorder.

We operate as a single operating segment engaged in the research, development and commercialization of pharmaceutical products, and our headquarters are located in Emeryville, California.

Basis of Presentation

The accompanying condensed consolidated financial statements have been prepared pursuant to generally accepted accounting principles in the United States (GAAP) for interim financial reporting and the rules and regulations of the Securities and Exchange Commission (SEC). The condensed consolidated financial statements do not include all of the information and note disclosures required by GAAP for complete financial statements and should therefore be read in conjunction with the consolidated financial statements and related notes included in our 2020 Annual Report on Form 10-K (2020 Form 10-K), which was filed with the SEC on March 1, 2021. In the opinion of management, these condensed consolidated financial statements reflect all adjustments, which are normal and recurring in nature, necessary for a fair statement of our financial position, results of operations and cash flows for the periods indicated. The results of operations for any interim period are not necessarily indicative of results of operations for any future period.

The accompanying condensed consolidated financial statements include the accounts of Zogenix, Inc. and its wholly-owned subsidiaries. Intercompany accounts and transactions have been eliminated in consolidation.

Liquidity

As of March 31, 2021, our cash, cash equivalents and marketable securities totaled $435.2 million. Excluding gains from two discrete business divestitures, we have incurred significant net losses and negative cash flows from operating activities since inception, resulting in an accumulated deficit of $1.4 billion as of March 31, 2021. We expect to continue to incur significant operating losses and negative cash flows from operations to support the sales and marketing of Fintepla for Dravet syndrome in the U.S. and Europe, potential commercialization of Fintepla for LGS, as well as continuing to advance our clinical programs. Additionally, we are obligated to make future milestone payments that are contingent upon the successful achievement of certain development, regulatory and sales-based milestone events related to Fintepla and MT1621. Historically, we have relied primarily on the proceeds from equity and convertible debt offerings to finance our operations. Until such time, if ever, we can generate a sufficient amount of revenue to finance our cash requirements, we may need to continue to rely on additional financing to achieve our business objectives. However, we may not be able to secure such financing in a timely manner or on favorable terms, if at all, and this risk could be exacerbated by the impact of COVID-19 on global economic conditions. Failure to raise sufficient capital when needed could require us to significantly delay, scale back or discontinue one or more of our product development programs or commercialization efforts or other aspects of our business plans, and our operating results and financial condition would be adversely affected.

XML

Accounting Policies

3 Months Ended

Mar. 31, 2021

Accounting Policies [Abstract]

Accounting Policies

Accounting Policies

Use of Estimates

The preparation of our condensed consolidated financial statements requires us to make estimates, judgments and assumptions that may affect the reported amounts of assets, liabilities, equity, revenues and expenses and related disclosure of contingent assets and liabilities. On an ongoing basis we evaluate our estimates, judgments and methodologies. We base our estimates on historical experience and on various other assumptions that we believe are reasonable, the results of which form the basis for making judgments about the carrying values of assets, liabilities and equity and the amount of revenues and expenses. Actual results may differ from those estimates.

Significant Accounting Policies

The significant accounting policies and estimates used in the preparation of the accompanying condensed consolidated financial statements are described in Note 2, Summary of Significant Accounting Policies to the consolidated financial statements in our 2020 Form 10-K. There have been no material changes in our significant accounting policies during the three months ended March 31, 2021.

Recently Issued Accounting Pronouncements Not Yet Adopted

Account Standard Update (ASU) 2020-06, Debt — Debt with Conversion and Other Options (subtopic 470-20) and Derivatives and Hedging — Contracts in Entity’s Own Equity (subtopic 815-40) (ASU 2020-06) simplifies the accounting for certain financial instruments with characteristics of liabilities and equity, including convertible debt instruments with cash conversion features. Specifically, ASU 2020-06 removes the existing guidance that we currently follow for our convertible senior notes, which requires entities to account for cash conversion features in equity separately from the host contract. These amendments are expected to result in more freestanding financial instruments qualifying for equity classification and, as a result, not accounted for as derivatives, as well as fewer embedded features requiring separate accounting from the host contract. In addition, ASU 2020-06 eliminates the treasury stock method when calculating diluted earnings per share for convertible instruments that can be settled in whole or in part with equity and requires the use of the if-converted method. Early adoption is permitted, but no earlier than the fiscal year beginning after December 15, 2020. The standard can be applied using a full or modified retrospective approach.    

ASU 2020-06 will be effective for us as of January 1, 2022. When effective, we expect the accounting for our convertible senior notes as a single unit of account will: i) increase the carrying value of our convertible notes to be closer to its outstanding principal balance, ii) decrease our interest expense over the expected life of the financial instrument, and iii) result in the debt instrument’s effective interest rate to be closer to the stated coupon rate. In addition, the use of the more favorable treasury stock method, which allows an entity with a stated policy of settling convertible instruments with a combination of cash and shares to exclude shares issuable upon conversion that it expects to settle with cash when calculating diluted earnings per share, is no longer permitted. Even if we have the intent and ability to settle conversions by paying the conversion value in cash up to the principal amount being converted and any excess in shares, the adoption of ASU 2020-06 will require that we presume such instruments will be settled by issuance of shares (the “if-converted method”). As a result, our diluted earnings per share under ASU 2020-06 may be lower than if we were able to apply the treasury stock method when calculating the dilutive effect of our Notes in earnings per share.

XML

Product Revenue and Concentration of Credit Risks

3 Months Ended

Mar. 31, 2021

Disaggregation of Revenue [Abstract]

Product Revenue and Concentration of Credit Risks

Product Revenue and Concentration of Credit Risks

Net Product Sales

Fintepla is distributed in the U.S. through an exclusive arrangement with a specialty distributor, who is our customer. The specialty distributor subsequently resells our product through its related specialty pharmacy provider to patients and health care providers. Separately, we have or may enter into payment arrangements with various third-party payers including pharmacy benefit managers, private healthcare insurers and government healthcare programs who provide coverage and reimbursement for our products that have been proscribed to a patient.

In February 2021, we began to distribute Fintepla in Europe (currently, in Germany) through a third-party logistics provider (3PL) for distribution to pharmacies throughout Germany. The pharmacies are our customers, who subsequently resell our product directly to patients and health care providers.

For the three months ended March 31 ,2021, total net product sales generated from Fintepla was $12.3 million, and consisted of $11.3 million derived in the United States and $1.0 million derived in Germany. Fintepla was approved by the FDA in June 2020 and the EMA in December 2020.

We record product revenue at the net sales price (transaction price), which includes estimates of consideration payable to our customers and third-party payers for which reserves are established and that result from government rebates, chargebacks, co-pay assistance, prompt-payment discounts and other allowances that are offered under arrangements between us, our customers, and third-party payers related to the sales of Fintepla.

The following table summarizes the provisions, and credits/payments, for sales-related deductions.

(In thousands)	Rebates		Trade Discounts, Distributor Fees and Other		Total
Balance at December 31, 2020	$	1,161	$	129	$	1,290
Current period provisions	1,904		593		2,497
Credits/payments	(774)		(481)		(1,255)
Balance at March 31, 2021	$	2,291	$	241	$	2,532

We generally invoice our customers and recognize revenue once our performance obligations are satisfied, at which point payment is unconditional. Accordingly, our arrangements with customers did not give rise to contract assets or liabilities during the three months ended March 31, 2021.

Concentration of Credit Risk and Major Customers

As is common in the pharmaceutical industry for products treating rare diseases, Fintepla is distributed through exclusive arrangements with a specialty distributor in the U.S. and through a 3PL who distributes to pharmacy providers throughout Germany. As a result, our accounts receivable balance at March 31, 2021 is highly concentrated with our U.S. customer accounting for over 90% of the balance and over 90% of net product revenue for the three months ended March 31, 2021. Accounts receivable are stated net of an allowance that reflects our current estimate of credit losses expected to occur over the life of the receivable. Estimates of our allowance for credit losses consider a number of factors including existing contractual payment terms, individual customer circumstances, historical payment patterns of our customers, a review of the local economic environment and its potential impact on expected future customer payment patterns. As of March 31, 2021 and December 31, 2020, we believe that the allowances for doubtful accounts, if any, are adequate based on our analysis of the specific business circumstances and expectations of collection for each of the underlying accounts.

XML

Collaboration Arrangement

3 Months Ended

Mar. 31, 2021

Organization, Consolidation and Presentation of Financial Statements [Abstract]

Collaboration Arrangement

Collaboration Arrangement

Nippon Shinyaku Co., Ltd

In March 2019, we entered into an agreement (Shinyaku Agreement) with Nippon Shinyaku Co., Ltd. (Shinyaku) for the exclusive distribution of Fintepla in Japan for the treatment of Dravet syndrome and LGS. No development rights or intellectual property licenses were transferred. As part of the Shinyaku Agreement, we are responsible for completing the global clinical development and all regulatory approval activities for Fintepla to support the submission of new drug applications in Japan for Dravet syndrome and LGS. Upon regulatory approval of Fintepla in Japan, Shinyaku will act as our exclusive distributor for Fintepla and will be responsible for the commercialization activities including the promotion, marketing, sale and distribution of Fintepla in Japan.

Shinyaku has agreed to support development and regulatory approval of Fintepla in Japan by actively participating in the design of non-clinical, clinical and manufacturing requirements needed for regulatory submission, actively planning and participating in product labeling decisions and discussions with the Japanese Ministry of Health, Labor and Welfare (MHLW) and obtained distribution exclusivity through the payment of an initial fixed consideration. The collaborative activities under the Shinyaku Agreement prior to regulatory approval are within the scope of the accounting guidance related to collaborative arrangements.

Pursuant to the terms of the agreement, Shinyaku agreed to make aggregate fixed payments of $20.0 million in scheduled installments over a two-year period from the date of the agreement. As of March 31, 2021, all fixed consideration has been received. In addition, we can earn up to $66.0 million from Shinyaku for the achievement of certain regulatory milestones for the treatment of Dravet syndrome and LGS. At contract inception and through March 31, 2021, the regulatory milestone variable consideration was fully constrained as the achievement of the events tied to these regulatory milestone payments was highly dependent on factors outside our control.

We can earn up to an additional $42.5 million tied to the achievement of certain net sales milestones by Shinyaku through the term of the agreement, which generally expires in 2045. Shinyaku will only become a customer and subject to revenue from contracts from customers accounting guidance after regulatory approval of Fintepla in Japan occurs and Shinyaku places purchase orders with us. To date, Shinyaku has not provided us with any purchase orders and thus no revenue has been recognized for the supply of Fintepla.

For the three months ended March 31, 2021 and 2020, collaboration revenue under this arrangement was $1.3 million and $1.2 million, respectively. As of March 31, 2021, the deferred revenue balance of $11.0 million was classified as either current or net of current portion in the accompanying condensed consolidated balance sheets

based on the period over which the collaboration revenue is expected to be recognized. We expect to recognize collaboration revenue related to these collaborative activities through the end of 2023.

XML

Strategic License Agreement

3 Months Ended

Mar. 31, 2021

Research and Development [Abstract]

Strategic License Agreement

Strategic License Agreement

Tevard Collaboration, Option and License Agreement

In October 2019, we entered into an option agreement with Tevard Biosciences (Tevard), a privately-held company focused on advancing novel gene therapies and other genetic epilepsies. In December 2020, we exercised the option on Tevard’s Dravet syndrome program and entered into a collaboration, option and license agreement with Tevard (the Tevard Agreement) and will be responsible for funding preclinical studies and clinical development for this program. The financial terms of the Tevard Agreement included an upfront payment of $5.2 million. In connection with the transaction, we also purchased a convertible promissory note issued by Tevard in the amount of $5.0 million. The note matures in December 2022 and carries interest at 3.5% per year. The note will automatically convert into equity securities issued by Tevard in their next equity financing transaction at a conversion price equal to the price paid per share by other investors of the financing transaction.

For the three months ended March 31, 2021, amounts payable to reimburse Tevard for its costs incurred under the Dravet syndrome program of $0.8 million were recorded as research and development expense. For the three months ended March 31, 2020, option maintenance fees of $1.5 million incurred prior to our opt-in of Tevard’s Dravet syndrome program in December 2020 were immediately expensed to acquired in-process research and development costs.

At the inception of the agreement and through March 31, 2021, Tevard is a variable interest entity in which we held variable interests through our licensed Dravet syndrome program and convertible promissory note. We determined that we are not the primary beneficiary of Tevard as we do not have voting control or other forms of power to direct activities that most significantly impact Tevard’s economic performance.

At each reporting period, we evaluate the note receivable for current expected credit loss by considering factors such as historical experience, market data, issuer-specific factors, and current economic conditions. As of March 31, 2021, no provision for current expected credit losses was deemed necessary based on the expected timing of an equity financing that would result in the automatic conversion of the note to equity securities of Tevard and their existing cash on hand was sufficient to meet their operating requirements prior to the consummation of a financing transaction.

As of March 31, 2021, we do not have any current legal or contractual obligations to provide financing to Tevard and our maximum exposure to future loss is limited to the $5.0 million note receivable. While we have committed to fund the Dravet syndrome development program for Tevard’s early discovery activities, our obligation to fund these efforts is contingent upon continued involvement in the program and/or the lack of any adverse events which could cause the discontinuance of the program. Our exposure to future losses is limited as we have the unilateral right to terminate the agreement with 180 days advanced notice.

XML

Cash, Cash Equivalents and Marketable Securities

3 Months Ended

Mar. 31, 2021

Cash and Cash Equivalents [Abstract]

Cash, Cash Equivalents and Marketable Securities

Cash, Cash Equivalents and Marketable SecuritiesThe following tables summarize the amortized cost and the estimated fair value of our cash, cash equivalents and marketable securities as of March 31, 2021 and December 31, 2020:

	March 31, 2021
(In thousands)	Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses		Estimated Fair Value
Current assets:
Cash	$	26,847	$	—	$	—	$	26,847
Cash equivalents:
Money market funds	38,974		—		—		38,974
Certificate of deposits	1,500		—		—		1,500
Commercial paper	18,996		—		—		18,996
Total cash and cash equivalents	86,317		—		—		86,317
Marketable securities:
U.S. Treasuries	26,924		6		—		26,930
Certificate of deposits	55,283		—		—		55,283
Commercial paper	233,419		—		—		233,419
Corporate debt securities	27,002		59		(2)		27,059
U.S. Government-sponsored enterprises debt securities	6,200		14		—		6,214
Total marketable securities	348,828		79		(2)		348,905
Total cash, cash equivalents and marketable securities	$	435,145	$	79	$	(2)	$	435,222

	December 31, 2020
(In thousands)	Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses		Estimated Fair Value
Current assets:
Cash	$	23,887	$	—	$	—	$	23,887
Cash equivalents:
Money market funds	80,986		—		—		80,986
Commercial paper	61,043		—		—		61,043
Certificate of deposits	1,000		—		—		1,000
Total cash equivalents	143,029		—		—		143,029
Total cash and cash equivalents	166,916		—		—		166,916
Marketable securities:
U.S. Treasuries	43,050		1		(1)		43,050
Commercial paper	210,986		—		—		210,986
Certificate of deposits	44,480		—		—		44,480
U.S. Government-sponsored enterprises debt securities	6,200		17		—		6,217
Corporate debt securities	33,288		172		—		33,460
Total marketable securities	338,004		190		(1)		338,193
Total cash, cash equivalents and marketable securities	$	504,920	$	190	$	(1)	$	505,109

As of March 31, 2021, all marketable securities held have maturity dates within one year or less. We regularly review our available-for-sale marketable securities in an unrealized loss position and evaluate the current expected credit loss by considering factors such as historical experience, market data, issuer-specific factors, and current economic conditions. As of March 31, 2021, the aggregate difference between the amortized cost and fair value of each security in an unrealized loss position was de minimis. Since any provision for expected credit losses for a security held is limited to the amount the fair value is less than its amortized cost, no allowance for expected credit loss was deemed necessary at March 31, 2021.

See Note 7 for further information regarding the fair value of our financial instruments.

XML

Fair Value Measurements

3 Months Ended

Mar. 31, 2021

Fair Value Disclosures [Abstract]

Fair Value Measurements

Fair Value Measurements

Fair value is defined as the price that would be received to sell an asset or paid to transfer a liability (an exit price) in the principal or most advantageous market for the asset or liability in an orderly transaction between market participants on the measurement date. A three-level valuation hierarchy has been established under GAAP for disclosure of fair value measurements. The valuation hierarchy is based on the transparency of inputs to the valuation of an asset or liability as of the measurement date. The three levels are defined as follows:

Level 1:Observable inputs such as quoted prices in active markets;

Level 2:Inputs, other than the quoted prices in active markets, that are observable either directly or indirectly; and

Level 3:Unobservable inputs in which there is little or no market data, which require the reporting entity to develop its own assumptions.

Our financial instruments consist primarily of cash and cash equivalents, marketable securities, notes receivable and other current assets, accounts payable and accrued liabilities, convertible senior notes and contingent consideration liability, and are reported at their respective fair values on our condensed consolidated balance sheets. The remaining financial instruments are carried at cost which approximates their respective fair values because of the short-term nature of these financial instruments. See Note 6 for further information regarding the amortized cost of our financial assets.

The following tables summarize assets and liabilities recognized or disclosed at fair value on a recurring basis as of March 31, 2021 and December 31, 2020:

	March 31, 2021
(In thousands)	Level 1		Level 2		Level 3		Total
Assets:
Cash equivalents:
Money market funds	$	38,974	$	—	$	—	$	38,974
Certificate of deposits	—		1,500		—		1,500
Commercial paper	—		18,996		—		$	18,996
Marketable securities:
U.S. Treasury securities	—		26,930		—		26,930
Certificate of deposits	—		55,283		—		55,283
Commercial debt securities	—		233,419		—		233,419
Commercial paper	—		27,059		—		27,059
U.S. Government-sponsored enterprises debt securities	—		6,214		—		6,214
Total(1)	$	38,974	$	369,401	$	—	$	408,375
Liabilities:
Contingent consideration	$	—	$	—	$	43,000	$	43,000

	December 31, 2020
(In thousands)	Level 1		Level 2		Level 3		Total
Assets:
Cash equivalents:
U.S. Treasuries	$	—	$	13,799	$	—	$	13,799
Money market funds	39,536		—		—		39,536
Certificate of deposits	—		3,008		—		3,008
Commercial paper	—		21,648		—		21,648
Marketable securities:
U.S. Treasuries	—		27,896		—		27,896
Commercial paper	—		101,951		—		101,951
U.S. Government-sponsored enterprises debt securities	—		6,219		—		6,219
Corporate debt securities	—		50,357		—		50,357
Certificate of deposits	—		41,284		—		41,284
Total(1)	$	39,536	$	266,162	$	—	$	305,698
Liabilities:
Contingent consideration	$	—	$	—	$	42,400	$	42,400

————————————

(1)Fair value is determined by taking into consideration valuations obtained from third-party pricing services. The third-party pricing services utilize industry standard valuation models, for which all significant inputs are observable, either directly or indirectly, to estimate fair value. These inputs include reported trades of and broker/dealer quotes on the same or similar securities; issuer credit spreads; benchmark securities; and other observable inputs.

Contingent Consideration Liability

As of March 31, 2021, our contingent consideration liability consisted of sales-based milestones for Fintepla, which resulted from our 2014 acquisition of Brabant. The maximum amount of future contingent consideration (undiscounted) that we could be required to pay was $45.0 million.

The following table provides a reconciliation of our contingent consideration liability measured at fair value on a recurring basis using significant unobservable inputs (Level 3) for the three months ended March 31, 2021 and 2020 (in thousands):

	Three Months Ended March 31,
	2021		2020
Balance at beginning of period	$	42,400	$	63,800
Change in fair value	600		(7,900)
Balance at end of period	$	43,000	$	55,900

For the three months ended March 31, 2021, the $0.6 million increase to the estimated fair value of the contingent consideration liability reflects the interest component of contingent consideration related to the passage of time. For the three months ended March 31, 2020, the $7.9 million was primarily due to changes to our probability-weighted estimates for achieving regulatory/commercial milestones and the use of a higher discount rate to reflect an increase in credit-adjusted interest rates.

The following table summarizes the significant unobservable inputs used in the fair value measurement of our contingent consideration liabilities as of March 31, 2021.

Fair Value as of March 31, 2021 (in thousands)	Valuation Technique	Unobservable Input	Range	Weighted Average(1)
$43,000	Discounted cash flow	Discount rate	1.9% — 3.0%	2.5%
		Probability of payment	100%	100%
		Projected year of payment	2021 — 2030	2022

————————————

(1)Unobservable inputs were weighted by the relative fair value of each sales-based milestone payment.

Convertible Senior Notes

As of March 31, 2021 and December 31, 2020, the estimated fair value of our convertible senior notes due 2027 was approximately $259.8 million and $260.5 million, respectively, and was determined based on a binomial lattice model with Level 2 inputs. When determining the estimated fair value of our Notes, we utilize a binomial lattice model which incorporates the terms and conditions of our convertible senior notes and market-based risk measurements that are indirectly observable, such as credit risk. The lattice model produces an estimated fair value based on changes in the price of the underlying common stock price over successive periods of time. An estimated yield based on comparable non-convertible debt instruments in the market is used to discount the cash flows.

XML

Balance Sheet Details

3 Months Ended

Mar. 31, 2021

Balance Sheet Related Disclosures [Abstract]

Balance Sheet Details

Balance Sheet Details

Inventory

The following table provides details of our inventory balance:

(In thousands)	March 31, 2021		December 31, 2020
Raw materials	$	659	$	391
Work in process	755		243
Finished goods	910		392
Total	$	2,324	$	1,026

Accrued and Other Current Liabilities

The following table provides details of accrued and other current liabilities:

(In thousands)	March 31, 2021		December 31, 2020
Accrued clinical trial expenses	$	14,405	$	16,477
Accrued compensation	7,135		10,917
Accrued milestone payment	—		15,000
Other accrued liabilities	9,209		12,570
Total	$	30,749	$	54,964

XML

Intangible Asset

3 Months Ended

Mar. 31, 2021

Goodwill and Intangible Assets Disclosure [Abstract]

Intangible Asset

Intangible Asset

Our intangible asset consists of worldwide development, commercialization and related intellectual property rights including patents and licenses for Fintepla, our first rare disease therapy approved for marketing in the U.S. and Europe.

The following table provides details of the carrying amount of our finite-lived intangible asset:

(In thousands)	March 31, 2021		December 31, 2020
Finite-lived intangible asset	$	102,500	$	102,500
Accumulated amortization	(5,913)		(3,942)
Total intangible asset, net	$	96,587	$	98,558

As of March 31, 2021 and December 31, 2020, the carrying value of the intangible asset will be amortized over its estimated remaining useful life of 12.3 years and 12.5 years, respectively. At March 31, 2021, the estimated amortization expense for each of the five succeeding years was approximately $7.9 million per year.

XML

Convertible Senior Notes

3 Months Ended

Mar. 31, 2021

Debt Disclosure [Abstract]

Convertible Senior Notes

Convertible Senior Notes

In September and October 2020, we issued $230.0 million aggregate principal amount of 2.75% convertible senior notes due 2027 (the Notes) and realized net proceeds of $222.5 million. The Notes are governed by an indenture (Indenture), dated as of September 28, 2020, between Zogenix and U.S. Bank National Association, as trustee. Under the Indenture, the Notes are senior, unsecured obligations of Zogenix, are equal in right of payment with its future senior, unsecured indebtedness of Zogenix, and structurally subordinated to all indebtedness and liabilities of its subsidiaries. Interest is payable semi-annually in arrears on April 1 and October 1 of each year, beginning on April 1, 2021 at a rate of 2.75% per year. The Notes mature on October 1, 2027, unless earlier repurchased, redeemed or converted. The Indenture contains customary terms and covenants and may become due and payable upon the occurrence of an event of default, but does not contain any financial covenants. As of March 31, 2021, we were in compliance with all covenants under the Indenture.

The Notes are convertible, subject to certain conditions described below, into shares of our common stock at an initial conversion rate of 41.1794 shares per $1,000 principal amount of the Notes, which represents an initial conversion price of approximately $24.28 per share, subject to adjustments upon the occurrence of certain events. Certain corporate events described in the Indenture may increase the conversion rate for holders who elect to convert their Notes in connection with such corporate event should they occur. We also may choose to repurchase outstanding Notes through open-market transactions, including through Rule 10b5-1 trading plan to facilitate open-market repurchases, or otherwise, from time to time.

Holders may convert the Notes in multiples of $1,000 principal amount at any time prior to October 1, 2027, but only in the following circumstances:

•during any calendar quarter ending after December 31, 2020, if our closing stock price exceeds 130% of the conversion price on each of at least 20 trading days of the last 30 consecutive trading days of the immediately preceding calendar quarter;

•during the five consecutive business day period after any 10 consecutive trading day period in which the Notes’ trading price is less than 98% of the product of our closing stock price times the conversion rate; or

•the occurrence of certain corporate events, such as a change of control, merger, default or liquidation.

In addition, holders may also convert their Notes at their option at any time beginning on July 1, 2027 until the close of business on the second scheduled trading day immediately before the maturity date for the Notes, without regard to the foregoing circumstances.

Upon conversion, we will pay or deliver, as the case may be, cash, shares of our common stock or a combination thereof at our election.

We may not redeem the Notes prior to October 7, 2024. On or after October 7, 2024, the Notes are redeemable for cash, in whole or in part (subject to minimum redemption amounts), at our option at any time, and from time to time, before the 40th scheduled trading day immediately before October 1, 2027, at a cash redemption price equal to 100% of the principal amount of the Notes to be redeemed, plus accrued and unpaid interest, if any, but only if our closing stock price exceeds 130% of the conversion price on (1) each of at least 20 trading days, whether or not consecutive, during the 30 consecutive trading days ending on, and including, the trading day immediately before the date we send the related redemption notice; and (2) the trading day immediately before the date we send such notice. In addition, calling any Note for redemption will constitute a make-whole fundamental change (as defined in the Indenture) with respect to that Note, in which case the conversion rate applicable to the conversion of that Note will be increased in certain circumstances if it is converted after it is called for redemption.

In accounting for the issuance of the Notes, we separated the Notes between a liability component and an equity component utilizing applicable guidance for convertible instruments that may be settled with a combination of cash and shares, at our election. This resulted in the recognition of $152.1 million as the liability component of the Notes. The carrying amount of the equity component of approximately $77.9 million, representing the conversion option, was determined by deducting the fair value of the liability component from the principal amount of the Notes. The difference between the principal amount of the Notes and the liability component (the debt discount) is amortized to interest expense using the effective interest method over the expected term of the Notes. The equity component of the Notes is included in additional paid-in capital in the condensed consolidated balance sheets. In accounting for debt issuance costs, we allocated the total amount incurred of $7.5 million to the liability and equity components using the same proportions as the principal amount of the Notes. Debt issuance costs attributable to the liability component of $4.9 million were recorded as debt discount and are being amortized to interest expense over the expected term of the Notes. Debt issuance costs attributable to the equity component of approximately $2.6 million were netted with the equity component within our condensed consolidated stockholders' equity.

The equity component balance of $75.3 million, net of allocated issuance costs, is not remeasured as long as the conversion option of the Notes continues to meet the conditions for equity classification. As of March 31, 2021, there have been no changes to the net carrying value of the equity component balance since the date of issuance of the Notes.

The following table provides additional details on the carrying amounts of our:

(in thousands)	March 31, 2021		December 31, 2020
Liability component:
Principal amount of Notes	$	230,000	$	230,000
Less: unamortized debt discount and issuance costs	(78,549)		(80,647)
Net carrying amount of Notes	$	151,451	$	149,353
Equity component — net carrying amount	$	75,333	$	75,333

For the three months ended March 31, 2021, total interest expense recognized related to our Notes consists of the following:

(in thousands)	Three Months Ended March 31, 2021
Contractual coupon interest	1,615
Amortization of debt discount and issuance costs	2,098
Total interest expense	$	3,713

For the three months ended March 31, 2021, the effective interest rate on the liability component of the Notes was 9.9%, which remained unchanged from the date of issuance. The unamortized debt discount and issuance costs of $78.5 million as of March 31, 2021 will be amortized over the remaining term of approximately 6.5 years. We had no interest expense for the same period in 2020 as we had no borrowings.

During the three months ended March 31, 2021, the closing price of our common stock did not exceed 130% of the applicable conversion price of our Notes on at least 20 of the last 30 consecutive trading days of the quarter; furthermore, no other conditions allowing holders of the Notes to convert have been met as of March 31, 2021. Therefore, the Notes are not convertible for the three months ending June 30, 2021 and are classified as long-term debt. Should the closing price conditions be met in a future quarter, the Notes will be convertible at the holders’ option during the immediately following quarter. Based on the closing price of our common stock of $19.52 per share on March 31, 2021, the if-converted value of the Notes was less than the outstanding principal balance.

XML

Stock-Based Compensation

3 Months Ended

Mar. 31, 2021

Share-based Payment Arrangement [Abstract]

Stock-Based Compensation

Stock-Based Compensation

Stock Options

The following is a summary of stock option activity for the three months ended March 31, 2021 (in thousands, except per share data):

	Shares	Weighted- Average Exercise Price per Share
Outstanding at December 31, 2020	5,311	$	29.12
Granted	946	18.96
Exercised	(1)	10.33
Canceled	(75)	33.73
Outstanding at March 31, 2021	6,181	$	27.51

Restricted Stock Units

Time-based restricted stock units (RSUs) and performance-based restricted stock units (PSUs) will be settled with our common stock on a one-to-one basis upon vesting. The following is a summary of our stock award activity for the three months ended March 31, 2021 (in thousands, except per share data):

	RSUs		PSUs		Total
December 31, 2020	393		—		393
Granted(1)	450		482		932
Vested	(119)		—		(119)
Canceled	(6)		(3)		(9)
Outstanding at March 31, 2021	718		479		1,197
(1) Weighted-average grant date fair value	$	18.76	$	19.60	$	19.20

For the three months ended March 31, 2021, we granted 0.5 million PSUs to employees and executive officers. The PSUs are subject to vesting based on various performance conditions including achievement of certain regulatory milestones, net product revenue targets and the number of patients with reimbursed therapy, subject to continued service by the employee. Compensation expense related to equity-based awards with performance conditions and terms that provide for a graded vesting schedule is recognized over the requisite service period on a straight-line basis for each separately vesting tranche of the award, and is based on the expected satisfaction of the performance conditions at each reporting date. For performance conditions associated with regulatory milestones, we determined the outcome is not probable of being achieved unless and until the occurrence of the event. As a result, compensation expense will only be recognized, at a point in time, when regulatory approval occurs. We expect stock-based compensation will fluctuate from period to period based on the timing of achievement of regulatory milestones and such fluctuations may be material. For performance conditions associated with the net product revenue and the number of patients receiving reimbursed therapy, we determined the outcome is probable of being achieved and stock-based compensation expense is recognized commencing at the grant date over the implicit service period.

The following table summarizes the components of total stock-based compensation expense included in our condensed consolidated statements of operations:

	Three Months Ended March 31,
(In thousands)	2021		2020
Research and development	$	3,299	$	2,729
Selling, general and administrative	4,799		3,665
Total	$	8,098	$	6,394

The following table summarizes stock-based compensation expense by award type included in our condensed consolidated statements of operations:

	Three Months Ended March 31,
(In thousands)	2021		2020
Time-based stock options and restricted stock units	$	7,475	$	6,242
Performance-based stock units	427		—
Employee stock purchase plan (ESPP)	196		152
Total	$	8,098	$	6,394

Shares reserved and available for future issuance under all employee equity plans as of March 31, 2021 and December 31, 2020 were 2.1 million shares and 3.9 million shares, respectively.

XML

Net Loss Per Share

3 Months Ended

Mar. 31, 2021

Earnings Per Share [Abstract]

Net Loss Per Share

Net Loss Per Share

Basic net loss per share is calculated by dividing net loss by the weighted average number of shares outstanding for the period. Diluted net loss per share is calculated by dividing net loss by the weighted average number of shares of common stock and potential dilutive common stock equivalents outstanding during the period if the effect is dilutive. Our potentially dilutive shares of common stock include outstanding stock options, restricted stock units, warrants to purchase common stock and rights under our Notes.

A reconciliation of the numerators and denominators used in computing net loss per share is as follows (in thousands, except per share amounts):

	Three Months Ended March 31,
	2021		2020
Numerator:
Net loss	$	(55,630)	$	(25,800)
Denominator:
Shares used in per share calculation	55,750		48,185
Net loss per share, basic and diluted	$	(1.00)	$	(0.54)

The following table presents the potential shares of common stock outstanding that were excluded from the calculation of diluted net loss per share for the periods presented because including them would have been anti-dilutive (in thousands):

	Three Months Ended March 31,
	2021	2020
Shares subject to outstanding stock options	5,476	4,450
Shares subject to outstanding restricted stock units	738	485
Shares subject to outstanding warrants to purchase common stock	28	28
Shares issuable upon conversion of Notes	9,430	—
Total	15,672	4,963

XML

United Kingdom (U.K.) Research and Development (R&D) Tax Relief Scheme	3 Months Ended
	Mar. 31, 2021
Other Income and Expenses [Abstract]
United Kingdom (U.K.) Research and Development (R&D) Tax Relief Scheme	United Kingdom (U.K.) Research and Development (R&D) Tax Relief SchemeWe conduct extensive research and development activities that benefit from U.K.’s small and medium-sized enterprises (SMEs) R&D tax relief scheme. Under this tax relief scheme, a SME can make an election (i) to receive an enhanced U.K. tax deduction on its eligible R&D activities or, when an SME entity is in a net operating loss position, or (ii) to surrender net operating losses that arise from its eligible R&D activities in exchange for a cash payment from the U.K. tax authorities. As the tax incentives may be received without regard to an entity’s actual tax liability, they are not subject to accounting for income taxes. Amounts recognized by us for cash payment claims under the SME R&D tax relief scheme are recorded as a component of other income after an election for tax relief has been made by submitting a claim for a discrete tax year and collectability is deemed probable and reasonably assured.In December 2019, we elected to surrender net operating losses by submitting claims to receive cash payments of $9.9 million and $9.8 million related to our 2017 and 2018 tax years, respectively. Upon approval of our submitted claims by the U.K. tax authorities in the first quarter of 2020, we recorded income of $19.7 million as a component of other income on the condensed consolidated statement of operations. For our 2019 tax year, we have not yet decided whether to seek tax relief by surrendering some of our losses for a tax credit cash rebate claim or electing to receive enhanced U.K. tax deductions on our eligible research and development activities. Under the U.K.’s tax legislation, there is a two-year window after the end of a tax year to seek relief under this tax relief scheme.

XML

Accounting Policies (Policies)

3 Months Ended

Mar. 31, 2021

Accounting Policies [Abstract]

Use of Estimates

Use of EstimatesThe preparation of our condensed consolidated financial statements requires us to make estimates, judgments and assumptions that may affect the reported amounts of assets, liabilities, equity, revenues and expenses and related disclosure of contingent assets and liabilities. On an ongoing basis we evaluate our estimates, judgments and methodologies. We base our estimates on historical experience and on various other assumptions that we believe are reasonable, the results of which form the basis for making judgments about the carrying values of assets, liabilities and equity and the amount of revenues and expenses. Actual results may differ from those estimates.

Recently Issued Accounting Pronouncements Not Yet Adopted

Recently Issued Accounting Pronouncements Not Yet Adopted

Account Standard Update (ASU) 2020-06, Debt — Debt with Conversion and Other Options (subtopic 470-20) and Derivatives and Hedging — Contracts in Entity’s Own Equity (subtopic 815-40) (ASU 2020-06) simplifies the accounting for certain financial instruments with characteristics of liabilities and equity, including convertible debt instruments with cash conversion features. Specifically, ASU 2020-06 removes the existing guidance that we currently follow for our convertible senior notes, which requires entities to account for cash conversion features in equity separately from the host contract. These amendments are expected to result in more freestanding financial instruments qualifying for equity classification and, as a result, not accounted for as derivatives, as well as fewer embedded features requiring separate accounting from the host contract. In addition, ASU 2020-06 eliminates the treasury stock method when calculating diluted earnings per share for convertible instruments that can be settled in whole or in part with equity and requires the use of the if-converted method. Early adoption is permitted, but no earlier than the fiscal year beginning after December 15, 2020. The standard can be applied using a full or modified retrospective approach.    

ASU 2020-06 will be effective for us as of January 1, 2022. When effective, we expect the accounting for our convertible senior notes as a single unit of account will: i) increase the carrying value of our convertible notes to be closer to its outstanding principal balance, ii) decrease our interest expense over the expected life of the financial instrument, and iii) result in the debt instrument’s effective interest rate to be closer to the stated coupon rate. In addition, the use of the more favorable treasury stock method, which allows an entity with a stated policy of settling convertible instruments with a combination of cash and shares to exclude shares issuable upon conversion that it expects to settle with cash when calculating diluted earnings per share, is no longer permitted. Even if we have the intent and ability to settle conversions by paying the conversion value in cash up to the principal amount being converted and any excess in shares, the adoption of ASU 2020-06 will require that we presume such instruments will be settled by issuance of shares (the “if-converted method”). As a result, our diluted earnings per share under ASU 2020-06 may be lower than if we were able to apply the treasury stock method when calculating the dilutive effect of our Notes in earnings per share.

Fair Value Measurements

Fair value is defined as the price that would be received to sell an asset or paid to transfer a liability (an exit price) in the principal or most advantageous market for the asset or liability in an orderly transaction between market participants on the measurement date. A three-level valuation hierarchy has been established under GAAP for disclosure of fair value measurements. The valuation hierarchy is based on the transparency of inputs to the valuation of an asset or liability as of the measurement date. The three levels are defined as follows:

Level 1:Observable inputs such as quoted prices in active markets;

Level 2:Inputs, other than the quoted prices in active markets, that are observable either directly or indirectly; and

Level 3:Unobservable inputs in which there is little or no market data, which require the reporting entity to develop its own assumptions.

Our financial instruments consist primarily of cash and cash equivalents, marketable securities, notes receivable and other current assets, accounts payable and accrued liabilities, convertible senior notes and contingent consideration liability, and are reported at their respective fair values on our condensed consolidated balance sheets. The remaining financial instruments are carried at cost which approximates their respective fair values because of the short-term nature of these financial instruments.

Net Loss Per Share

Basic net loss per share is calculated by dividing net loss by the weighted average number of shares outstanding for the period. Diluted net loss per share is calculated by dividing net loss by the weighted average number of shares of common stock and potential dilutive common stock equivalents outstanding during the period if the effect is dilutive. Our potentially dilutive shares of common stock include outstanding stock options, restricted stock units, warrants to purchase common stock and rights under our Notes.

XML

Product Revenue and Concentration of Credit Risks (Tables)

3 Months Ended

Mar. 31, 2021

Disaggregation of Revenue [Abstract]

Revenue Provisions, and Credits or Payments for Sales-related Deductions

The following table summarizes the provisions, and credits/payments, for sales-related deductions.

(In thousands)	Rebates		Trade Discounts, Distributor Fees and Other		Total
Balance at December 31, 2020	$	1,161	$	129	$	1,290
Current period provisions	1,904		593		2,497
Credits/payments	(774)		(481)		(1,255)
Balance at March 31, 2021	$	2,291	$	241	$	2,532

XML

Cash, Cash Equivalents and Marketable Securities (Tables)

3 Months Ended

Mar. 31, 2021

Cash and Cash Equivalents [Abstract]

Amortized cost and fair value of cash, cash equivalents and marketable securities

The following tables summarize the amortized cost and the estimated fair value of our cash, cash equivalents and marketable securities as of March 31, 2021 and December 31, 2020:

	March 31, 2021
(In thousands)	Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses		Estimated Fair Value
Current assets:
Cash	$	26,847	$	—	$	—	$	26,847
Cash equivalents:
Money market funds	38,974		—		—		38,974
Certificate of deposits	1,500		—		—		1,500
Commercial paper	18,996		—		—		18,996
Total cash and cash equivalents	86,317		—		—		86,317
Marketable securities:
U.S. Treasuries	26,924		6		—		26,930
Certificate of deposits	55,283		—		—		55,283
Commercial paper	233,419		—		—		233,419
Corporate debt securities	27,002		59		(2)		27,059
U.S. Government-sponsored enterprises debt securities	6,200		14		—		6,214
Total marketable securities	348,828		79		(2)		348,905
Total cash, cash equivalents and marketable securities	$	435,145	$	79	$	(2)	$	435,222

	December 31, 2020
(In thousands)	Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses		Estimated Fair Value
Current assets:
Cash	$	23,887	$	—	$	—	$	23,887
Cash equivalents:
Money market funds	80,986		—		—		80,986
Commercial paper	61,043		—		—		61,043
Certificate of deposits	1,000		—		—		1,000
Total cash equivalents	143,029		—		—		143,029
Total cash and cash equivalents	166,916		—		—		166,916
Marketable securities:
U.S. Treasuries	43,050		1		(1)		43,050
Commercial paper	210,986		—		—		210,986
Certificate of deposits	44,480		—		—		44,480
U.S. Government-sponsored enterprises debt securities	6,200		17		—		6,217
Corporate debt securities	33,288		172		—		33,460
Total marketable securities	338,004		190		(1)		338,193
Total cash, cash equivalents and marketable securities	$	504,920	$	190	$	(1)	$	505,109

XML

Fair Value Measurements (Tables)

3 Months Ended

Mar. 31, 2021

Fair Value Disclosures [Abstract]

Assets measured at fair value on recurring basis

The following tables summarize assets and liabilities recognized or disclosed at fair value on a recurring basis as of March 31, 2021 and December 31, 2020:

	March 31, 2021
(In thousands)	Level 1		Level 2		Level 3		Total
Assets:
Cash equivalents:
Money market funds	$	38,974	$	—	$	—	$	38,974
Certificate of deposits	—		1,500		—		1,500
Commercial paper	—		18,996		—		$	18,996
Marketable securities:
U.S. Treasury securities	—		26,930		—		26,930
Certificate of deposits	—		55,283		—		55,283
Commercial debt securities	—		233,419		—		233,419
Commercial paper	—		27,059		—		27,059
U.S. Government-sponsored enterprises debt securities	—		6,214		—		6,214
Total(1)	$	38,974	$	369,401	$	—	$	408,375
Liabilities:
Contingent consideration	$	—	$	—	$	43,000	$	43,000

	December 31, 2020
(In thousands)	Level 1		Level 2		Level 3		Total
Assets:
Cash equivalents:
U.S. Treasuries	$	—	$	13,799	$	—	$	13,799
Money market funds	39,536		—		—		39,536
Certificate of deposits	—		3,008		—		3,008
Commercial paper	—		21,648		—		21,648
Marketable securities:
U.S. Treasuries	—		27,896		—		27,896
Commercial paper	—		101,951		—		101,951
U.S. Government-sponsored enterprises debt securities	—		6,219		—		6,219
Corporate debt securities	—		50,357		—		50,357
Certificate of deposits	—		41,284		—		41,284
Total(1)	$	39,536	$	266,162	$	—	$	305,698
Liabilities:
Contingent consideration	$	—	$	—	$	42,400	$	42,400

————————————

(1)Fair value is determined by taking into consideration valuations obtained from third-party pricing services. The third-party pricing services utilize industry standard valuation models, for which all significant inputs are observable, either directly or indirectly, to estimate fair value. These inputs include reported trades of and broker/dealer quotes on the same or similar securities; issuer credit spreads; benchmark securities; and other observable inputs.

Liabilities measured at fair value on recurring basis

The following tables summarize assets and liabilities recognized or disclosed at fair value on a recurring basis as of March 31, 2021 and December 31, 2020:

	March 31, 2021
(In thousands)	Level 1		Level 2		Level 3		Total
Assets:
Cash equivalents:
Money market funds	$	38,974	$	—	$	—	$	38,974
Certificate of deposits	—		1,500		—		1,500
Commercial paper	—		18,996		—		$	18,996
Marketable securities:
U.S. Treasury securities	—		26,930		—		26,930
Certificate of deposits	—		55,283		—		55,283
Commercial debt securities	—		233,419		—		233,419
Commercial paper	—		27,059		—		27,059
U.S. Government-sponsored enterprises debt securities	—		6,214		—		6,214
Total(1)	$	38,974	$	369,401	$	—	$	408,375
Liabilities:
Contingent consideration	$	—	$	—	$	43,000	$	43,000

	December 31, 2020
(In thousands)	Level 1		Level 2		Level 3		Total
Assets:
Cash equivalents:
U.S. Treasuries	$	—	$	13,799	$	—	$	13,799
Money market funds	39,536		—		—		39,536
Certificate of deposits	—		3,008		—		3,008
Commercial paper	—		21,648		—		21,648
Marketable securities:
U.S. Treasuries	—		27,896		—		27,896
Commercial paper	—		101,951		—		101,951
U.S. Government-sponsored enterprises debt securities	—		6,219		—		6,219
Corporate debt securities	—		50,357		—		50,357
Certificate of deposits	—		41,284		—		41,284
Total(1)	$	39,536	$	266,162	$	—	$	305,698
Liabilities:
Contingent consideration	$	—	$	—	$	42,400	$	42,400

————————————

(1)Fair value is determined by taking into consideration valuations obtained from third-party pricing services. The third-party pricing services utilize industry standard valuation models, for which all significant inputs are observable, either directly or indirectly, to estimate fair value. These inputs include reported trades of and broker/dealer quotes on the same or similar securities; issuer credit spreads; benchmark securities; and other observable inputs.

Reconciliation of liabilities measured at fair value using significant unobservable inputs (Level 3)

The following table provides a reconciliation of our contingent consideration liability measured at fair value on a recurring basis using significant unobservable inputs (Level 3) for the three months ended March 31, 2021 and 2020 (in thousands):

	Three Months Ended March 31,
	2021		2020
Balance at beginning of period	$	42,400	$	63,800
Change in fair value	600		(7,900)
Balance at end of period	$	43,000	$	55,900

Significant inputs used in fair value measurement

The following table summarizes the significant unobservable inputs used in the fair value measurement of our contingent consideration liabilities as of March 31, 2021.

Fair Value as of March 31, 2021 (in thousands)	Valuation Technique	Unobservable Input	Range	Weighted Average(1)
$43,000	Discounted cash flow	Discount rate	1.9% — 3.0%	2.5%
		Probability of payment	100%	100%
		Projected year of payment	2021 — 2030	2022

————————————

(1)Unobservable inputs were weighted by the relative fair value of each sales-based milestone payment.

XML

Balance Sheet Details (Tables)

3 Months Ended

Mar. 31, 2021

Balance Sheet Related Disclosures [Abstract]

Schedule of Inventory

The following table provides details of our inventory balance:

(In thousands)	March 31, 2021		December 31, 2020
Raw materials	$	659	$	391
Work in process	755		243
Finished goods	910		392
Total	$	2,324	$	1,026

Details of accrued and other current liabilities

The following table provides details of accrued and other current liabilities:

(In thousands)	March 31, 2021		December 31, 2020
Accrued clinical trial expenses	$	14,405	$	16,477
Accrued compensation	7,135		10,917
Accrued milestone payment	—		15,000
Other accrued liabilities	9,209		12,570
Total	$	30,749	$	54,964

XML

Intangible Asset (Tables)

3 Months Ended

Mar. 31, 2021

Goodwill and Intangible Assets Disclosure [Abstract]

Schedule of Intangible Assets

The following table provides details of the carrying amount of our finite-lived intangible asset:

(In thousands)	March 31, 2021		December 31, 2020
Finite-lived intangible asset	$	102,500	$	102,500
Accumulated amortization	(5,913)		(3,942)
Total intangible asset, net	$	96,587	$	98,558

XML

Convertible Senior Notes (Tables)

3 Months Ended

Mar. 31, 2021

Debt Disclosure [Abstract]

Long-Term Debt

The following table provides additional details on the carrying amounts of our:

(in thousands)	March 31, 2021		December 31, 2020
Liability component:
Principal amount of Notes	$	230,000	$	230,000
Less: unamortized debt discount and issuance costs	(78,549)		(80,647)
Net carrying amount of Notes	$	151,451	$	149,353
Equity component — net carrying amount	$	75,333	$	75,333

For the three months ended March 31, 2021, total interest expense recognized related to our Notes consists of the following:

(in thousands)	Three Months Ended March 31, 2021
Contractual coupon interest	1,615
Amortization of debt discount and issuance costs	2,098
Total interest expense	$	3,713

XML

Stock-Based Compensation (Tables)

3 Months Ended

Mar. 31, 2021

Share-based Payment Arrangement [Abstract]

Summary of stock option activity

The following is a summary of stock option activity for the three months ended March 31, 2021 (in thousands, except per share data):

	Shares	Weighted- Average Exercise Price per Share
Outstanding at December 31, 2020	5,311	$	29.12
Granted	946	18.96
Exercised	(1)	10.33
Canceled	(75)	33.73
Outstanding at March 31, 2021	6,181	$	27.51

Schedule of restricted stock unit activity

The following is a summary of our stock award activity for the three months ended March 31, 2021 (in thousands, except per share data):

	RSUs		PSUs		Total
December 31, 2020	393		—		393
Granted(1)	450		482		932
Vested	(119)		—		(119)
Canceled	(6)		(3)		(9)
Outstanding at March 31, 2021	718		479		1,197
(1) Weighted-average grant date fair value	$	18.76	$	19.60	$	19.20

Stock-based compensation expense

The following table summarizes the components of total stock-based compensation expense included in our condensed consolidated statements of operations:

	Three Months Ended March 31,
(In thousands)	2021		2020
Research and development	$	3,299	$	2,729
Selling, general and administrative	4,799		3,665
Total	$	8,098	$	6,394

The following table summarizes stock-based compensation expense by award type included in our condensed consolidated statements of operations:

	Three Months Ended March 31,
(In thousands)	2021		2020
Time-based stock options and restricted stock units	$	7,475	$	6,242
Performance-based stock units	427		—
Employee stock purchase plan (ESPP)	196		152
Total	$	8,098	$	6,394

XML

Net Loss Per Share (Tables)

3 Months Ended

Mar. 31, 2021

Earnings Per Share [Abstract]

Basic and diluted net loss per share

A reconciliation of the numerators and denominators used in computing net loss per share is as follows (in thousands, except per share amounts):

	Three Months Ended March 31,
	2021		2020
Numerator:
Net loss	$	(55,630)	$	(25,800)
Denominator:
Shares used in per share calculation	55,750		48,185
Net loss per share, basic and diluted	$	(1.00)	$	(0.54)

Schedule of antidilutive securities excluded from computation of diluted net loss per share

The following table presents the potential shares of common stock outstanding that were excluded from the calculation of diluted net loss per share for the periods presented because including them would have been anti-dilutive (in thousands):

	Three Months Ended March 31,
	2021	2020
Shares subject to outstanding stock options	5,476	4,450
Shares subject to outstanding restricted stock units	738	485
Shares subject to outstanding warrants to purchase common stock	28	28
Shares issuable upon conversion of Notes	9,430	—
Total	15,672	4,963

XML

Organization, Basis of Presentation and Liquidity - Narrative (Details) $ in Thousands	3 Months Ended
	Mar. 31, 2021 USD ($) program divestiture segment	Dec. 31, 2020 USD ($)
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Number of late-stage development programs | program	2
Number of operating segments | segment	1
Total cash, cash equivalents and short-term investments, estimated fair value	$ 435,222	$ 505,109
Number of discrete business divestitures | divestiture	2
Accumulated deficit	$ 1,380,470	$ 1,324,840

XML

Product Revenue and Concentration of Credit Risks - Narrative (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Disaggregation of Revenue [Line Items]
Net product sales	$ 12,349	$ 0
Geographic Concentration Risk [Member] | Accounts Receivable
Disaggregation of Revenue [Line Items]
Concentration of credit risk and major customers (percent)	90.00%
Geographic Concentration Risk [Member] | Product revenue
Disaggregation of Revenue [Line Items]
Concentration of credit risk and major customers (percent)	90.00%
United States
Disaggregation of Revenue [Line Items]
Net product sales	$ 11,300
Germany
Disaggregation of Revenue [Line Items]
Net product sales	$ 1,000

XML

Product Revenue and Concentration of Credit Risks - Revenue Provisions, and Credits or Payments for Sales-related Deductions (Details) $ in Thousands	3 Months Ended
	Mar. 31, 2021 USD ($)
Sales-related Provisions, Credits and Payments [Roll Forward]
Balance at December 31, 2020	$ 1,290
Current period provisions	2,497
Credits/payments	(1,255)
Balance at March 31, 2021	2,532
Rebates
Sales-related Provisions, Credits and Payments [Roll Forward]
Balance at December 31, 2020	1,161
Current period provisions	1,904
Credits/payments	(774)
Balance at March 31, 2021	2,291
Trade Discounts, Distributor Fees and Other
Sales-related Provisions, Credits and Payments [Roll Forward]
Balance at December 31, 2020	129
Current period provisions	593
Credits/payments	(481)
Balance at March 31, 2021	$ 241

XML

Collaboration Arrangement (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020	Mar. 31, 2019
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Collaboration revenue	$ 1,335	$ 1,249
Nippon Shinyaku Co., Ltd. (Shinyaku) | Collaborative arrangement
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Collaboration revenue	1,300	$ 1,200
Deferred revenue	11,000
Nippon Shinyaku Co., Ltd. (Shinyaku) | Collaborative arrangement | Fixed consideration
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Performance obligation at inception of arrangement			$ 20,000
Nippon Shinyaku Co., Ltd. (Shinyaku) | Collaborative arrangement | Fixed consideration | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2019-04-01
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Timing of consideration to be received			2 years
Nippon Shinyaku Co., Ltd. (Shinyaku) | Collaborative arrangement | Achievement of regulatory milestones | Variable consideration
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Amount that can be earned upon achievement of milestone	66,000
Nippon Shinyaku Co., Ltd. (Shinyaku) | Collaborative arrangement | Achievement of net sales milestones | Variable consideration
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Amount that can be earned upon achievement of net sales milestone	$ 42,500

XML

Strategic License Agreement (Details) - Tevard Biosciences (Tevard) - Strategic license agreement - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2021	Oct. 31, 2019
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Upfront payment		$ 5.2
Promissory notes purchased		$ 5.0
Stated interest rate (percent)		3.50%
Research and development expense	$ 0.8
Option maintenance fees	1.5
Maximum exposure to future loss	$ 5.0

XML

Cash, Cash Equivalents and Marketable Securities (Details) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Cash and Cash Equivalents [Line Items]
Cash	$ 26,847	$ 23,887
Cash equivalents:		143,029
Total cash and cash equivalents	86,317	166,916
Marketable securities, amortized cost	348,828	338,004
Marketable securities, gross unrealized gains	79	190
Marketable securities, gross unrealized losses	(2)	(1)
Marketable securities, estimated fair value	348,905	338,193
Total cash, cash equivalents and marketable securities, amortized cost	435,145	504,920
Total cash, cash equivalents and marketable securities	435,222	505,109
U.S. Treasuries
Cash and Cash Equivalents [Line Items]
Marketable securities, amortized cost	26,924	43,050
Marketable securities, gross unrealized gains	6	1
Marketable securities, gross unrealized losses	0	(1)
Marketable securities, estimated fair value	26,930	43,050
Money market funds
Cash and Cash Equivalents [Line Items]
Cash equivalents:	38,974	80,986
Certificate of deposits
Cash and Cash Equivalents [Line Items]
Cash equivalents:	1,500	1,000
Marketable securities, amortized cost	55,283	44,480
Marketable securities, gross unrealized gains	0	0
Marketable securities, gross unrealized losses	0	0
Marketable securities, estimated fair value	55,283	44,480
Commercial paper
Cash and Cash Equivalents [Line Items]
Cash equivalents:	18,996	61,043
Marketable securities, amortized cost	233,419	210,986
Marketable securities, gross unrealized gains	0	0
Marketable securities, gross unrealized losses	0	0
Marketable securities, estimated fair value	233,419	210,986
Corporate debt securities
Cash and Cash Equivalents [Line Items]
Marketable securities, amortized cost	27,002	33,288
Marketable securities, gross unrealized gains	59	172
Marketable securities, gross unrealized losses	(2)	0
Marketable securities, estimated fair value	27,059	33,460
U.S. Government-sponsored enterprises debt securities
Cash and Cash Equivalents [Line Items]
Marketable securities, amortized cost	6,200	6,200
Marketable securities, gross unrealized gains	14	17
Marketable securities, gross unrealized losses	0	0
Marketable securities, estimated fair value	$ 6,214	$ 6,217

XML

Fair Value Measurements - Assets and Liabilities Measured at Fair Value on Recurring Basis (Details) - USD ($)	Mar. 31, 2021	Dec. 31, 2020
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Marketable securities:	$ 348,905,000	$ 338,193,000
Total assets	408,375,000	305,698,000
Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total assets	38,974,000	39,536,000
Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total assets	369,401,000	266,162,000
Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total assets	0	0
Contingent consideration	43,000,000
Contingent consideration
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Contingent consideration	43,000,000	42,400,000
Contingent consideration | Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Contingent consideration	0	0
Contingent consideration | Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Contingent consideration	0	0
Contingent consideration | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Contingent consideration	43,000,000	42,400,000
U.S. Treasuries
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash equivalents:		13,799,000
Marketable securities:	26,930,000	27,896,000
U.S. Treasuries | Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash equivalents:		0
Marketable securities:	0	0
U.S. Treasuries | Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash equivalents:		13,799,000
Marketable securities:	26,930,000	27,896,000
U.S. Treasuries | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash equivalents:		0
Marketable securities:	0	0
Money market funds
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash equivalents:	38,974,000	39,536,000
Money market funds | Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash equivalents:	38,974,000	39,536,000
Money market funds | Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash equivalents:	0	0
Money market funds | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash equivalents:	0	0
Certificate of deposits
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash equivalents:	1,500,000	3,008,000
Marketable securities:	55,283,000	41,284,000
Certificate of deposits | Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash equivalents:	0	0
Marketable securities:	0	0
Certificate of deposits | Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash equivalents:	1,500,000	3,008,000
Marketable securities:	55,283,000	41,284,000
Certificate of deposits | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash equivalents:	0	0
Marketable securities:	0	0
Commercial debt securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Marketable securities:	233,419,000
Commercial debt securities | Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Marketable securities:	0
Commercial debt securities | Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Marketable securities:	233,419,000
Commercial debt securities | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Marketable securities:	0
Commercial paper
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash equivalents:	18,996,000	21,648,000
Marketable securities:	27,059,000	101,951,000
Commercial paper | Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash equivalents:	0	0
Marketable securities:	0	0
Commercial paper | Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash equivalents:	18,996,000	21,648,000
Marketable securities:	27,059,000	101,951,000
Commercial paper | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash equivalents:	0	0
Marketable securities:	0	0
U.S. Government-sponsored enterprises debt securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Marketable securities:	6,214,000	6,219,000
U.S. Government-sponsored enterprises debt securities | Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Marketable securities:	0	0
U.S. Government-sponsored enterprises debt securities | Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Marketable securities:	6,214,000	6,219,000
U.S. Government-sponsored enterprises debt securities | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Marketable securities:	0	0
Corporate debt securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Marketable securities:		50,357,000
Corporate debt securities | Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Marketable securities:		0
Corporate debt securities | Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Marketable securities:		50,357,000
Corporate debt securities | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Marketable securities:		$ 0
ZX008
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Potential contingent consideration payment, maximum	$ 45,000,000.0

XML

Fair Value Measurements - Reconciliation of Liabilities Measured at Fair Value Using Significant Unobservable Inputs (Details) - Contingent consideration - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Balance at beginning of period	$ 42,400	$ 63,800
Change in fair value	600	(7,900)
Balance at end of period	$ 43,000	$ 55,900

XML

Fair Value Measurements - Significant Inputs Used in Fair Value Measurement (Details) $ in Thousands	Mar. 31, 2021 USD ($)	Dec. 31, 2020 USD ($)
Initial Notes | Convertible Notes
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Fair value of convertible notes	$ 259,800	$ 260,500
Level 3
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Fair value	$ 43,000
Discount rate | Discounted cash flow | Minimum
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Measurement input (percent)	0.019
Discount rate | Discounted cash flow | Maximum
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Measurement input (percent)	0.030
Discount rate | Discounted cash flow | Weighted average
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Measurement input (percent)	0.025
Probability of payment | Discounted cash flow | Minimum
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Measurement input (percent)	1
Probability of payment | Discounted cash flow | Weighted average
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Measurement input (percent)	1

XML

Balance Sheet Details - Components of Inventory (Details) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Balance Sheet Related Disclosures [Abstract]
Raw materials	$ 659	$ 391
Work in process	755	243
Finished goods	910	392
Total	2,324	1,026
Accrued compensation	$ 7,135	$ 10,917

XML

Balance Sheet Details - Details of Accrued and Other Current Liabilities (Details) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Balance Sheet Related Disclosures [Abstract]
Accrued clinical trial expenses	$ 14,405	$ 16,477
Accrued compensation	7,135	10,917
Accrued milestone payment	0	15,000
Other accrued liabilities	9,209	12,570
Total	$ 30,749	$ 54,964

XML

Intangible Asset - Schedule of Intangible Assets (Details) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Goodwill and Intangible Assets Disclosure [Abstract]
Finite-lived intangible asset	$ 102,500	$ 102,500
Accumulated amortization	(5,913)	(3,942)
Total intangible asset, net	$ 96,587	$ 98,558

XML

Intangible Asset - Estimated Amortization Expense (Details) - USD ($) $ in Millions	3 Months Ended	12 Months Ended
	Mar. 31, 2021	Dec. 31, 2020
Goodwill and Intangible Assets Disclosure [Abstract]
Estimated useful life of intangible asset	12 years 3 months 18 days	12 years 6 months
Finite-Lived Intangible Assets, Amortization Expense, Maturity Schedule [Abstract]
Succeeding year 1	$ 7.9
Succeeding year 2	7.9
Succeeding year 3	7.9
Succeeding year 4	7.9
Succeeding year 5	$ 7.9

XML

Convertible Senior Notes (Details)		1 Months Ended	2 Months Ended	3 Months Ended
	Sep. 28, 2020	Oct. 05, 2020 USD ($)	Oct. 31, 2020 USD ($) day $ / shares	Mar. 31, 2021 USD ($) $ / shares	Mar. 31, 2020 USD ($)	Dec. 31, 2020 USD ($)
Debt Instrument [Line Items]
Stock price (in usd per share) | $ / shares				$ 19.52
The Notes | Convertible Notes
Debt Instrument [Line Items]
Aggregate principal amount			$ 230,000,000.0
Net proceeds realized			$ 222,500,000
Conversion ratio	0.0411794
Conversion price (in usd per share) | $ / shares			$ 24.28
Multiples of principle amount available as optional conversion to holders			$ 1,000
Liability component allocation of issuance		$ 152,100,000
Carrying amount of equity component		77,900,000
Issuance costs incurred		7,500,000
Debt issuance costs attributable to the liability component		4,900,000
Debt issuance costs attributable to the equity component		2,600,000
Equity component of convertible senior notes		$ 75,300,000
Effective interest rate (percent)				9.90%
Unamortized debt discount and issuance costs				$ 78,500,000
Amortization period of unamortized issuance costs				6 years 6 months
Total interest expense				$ 3,713,000
The Notes | Convertible Notes | Conversion circumstance, one
Debt Instrument [Line Items]
Conversion price threshold (percent)			130.00%
Conversion threshold in days | day			20
Conversion threshold in consecutive days | day			30
The Notes | Convertible Notes | Conversion circumstance, two
Debt Instrument [Line Items]
Conversion price threshold (percent)			98.00%
Conversion threshold in days | day			5
Conversion threshold in consecutive days | day			10
The Notes | Convertible Notes | Conversion circumstance, three
Debt Instrument [Line Items]
Conversion price threshold (percent)			130.00%	130.00%
Conversion threshold in days | day			20
Conversion threshold in consecutive days | day			30
Redemption price percentage of principal (percent)			100.00%
Initial Notes | Convertible Notes
Debt Instrument [Line Items]
Stated interest rate (percent)			2.75%
Unamortized debt discount and issuance costs				$ 78,549,000		$ 80,647,000
Total interest expense					$ 0
Borrowings				$ 151,451,000	$ 0	$ 149,353,000

XML

Convertible Senior Notes - Schedule of Convertible Debt (Details) - USD ($)	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020	Dec. 31, 2020
Debt Instrument [Line Items]
Amortization of debt discount and issuance costs	$ 2,098,000	$ 0
Initial Notes | Convertible Notes
Debt Instrument [Line Items]
Principal amount of Notes	230,000,000		$ 230,000,000
Less: unamortized debt discount and issuance costs	(78,549,000)		(80,647,000)
Net carrying amount of Notes	151,451,000	0	149,353,000
Total interest expense		$ 0
The Notes | Convertible Notes
Debt Instrument [Line Items]
Less: unamortized debt discount and issuance costs	(78,500,000)
Equity component — net carrying amount	75,333,000		$ 75,333,000
Contractual coupon interest	1,615,000
Amortization of debt discount and issuance costs	2,098,000
Total interest expense	$ 3,713,000

XML

Stock-Based Compensation - Options Activity (Details) shares in Thousands	3 Months Ended
	Mar. 31, 2021 $ / shares shares
Shares (in thousands)
Options outstanding, beginning of period (in shares) | shares	5,311
Granted (in shares) | shares	946
Exercised (in shares) | shares	(1)
Canceled (in shares) | shares	(75)
Options outstanding, end of period (in shares) | shares	6,181
Weighted- Average Exercise Price per Share
Outstanding weighted average exercise price, beginning balance (in usd per share) | $ / shares	$ 29.12
Granted weighted average exercise price (in usd per share) | $ / shares	18.96
Exercised weighted average exercise price (in usd per share) | $ / shares	10.33
Canceled weighted average exercise price (in usd per share) | $ / shares	33.73
Outstanding weighted average exercise price, ending balance (in usd per share) | $ / shares	$ 27.51

XML

Stock-Based Compensation - Restricted Stock Unit Activity (Details) shares in Thousands	3 Months Ended
	Mar. 31, 2021 $ / shares shares
RSUs
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number of Shares [Roll Forward]
Outstanding at beginning of period (in shares)	393
Granted (in shares)	450
Vested (in shares)	(119)
Canceled (in shares)	(6)
Outstanding at end of period (in shares)	718
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value [Abstract]
Granted - Weighted average fair value per share at grant date (in usd per share) | $ / shares	$ 18.76
PSUs
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number of Shares [Roll Forward]
Outstanding at beginning of period (in shares)	0
Granted (in shares)	482
Vested (in shares)	0
Canceled (in shares)	(3)
Outstanding at end of period (in shares)	479
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value [Abstract]
Granted - Weighted average fair value per share at grant date (in usd per share) | $ / shares	$ 19.60
Stock awards
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number of Shares [Roll Forward]
Outstanding at beginning of period (in shares)	393
Granted (in shares)	932
Vested (in shares)	(119)
Canceled (in shares)	(9)
Outstanding at end of period (in shares)	1,197
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value [Abstract]
Granted - Weighted average fair value per share at grant date (in usd per share) | $ / shares	$ 19.20

XML

Stock-Based Compensation - Additional Information (Details) - shares shares in Thousands	3 Months Ended
	Mar. 31, 2021	Dec. 31, 2020
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares reserved and available for future issuance (shares)	2,100	3,900
PSUs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vested (shares)	0
PSUs granted (in shares)	482

XML

Stock-Based Compensation - Stock-Based Compensation Expense (Detail) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
	Mar. 31, 2020	Dec. 31, 2020
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Stock-based compensation expense	$ 8,098	$ 6,394
Time-based stock options and restricted stock units
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Stock-based compensation expense	7,475	6,242
Performance-based stock units
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Stock-based compensation expense	427	0
Employee stock purchase plan (ESPP)
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Stock-based compensation expense	196	152
Research and development
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Stock-based compensation expense	3,299	2,729
Selling, general and administrative
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Stock-based compensation expense	$ 4,799	$ 3,665

XML

Net Loss Per Share - Reconciliation of Numerator and Denominators in Computing Net Loss per Share (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Numerator:
Net loss	$ (55,630)	$ (25,800)
Denominator:
Shares used in per share calculation (in shares)	55,750	48,185
Net loss per share, basic and diluted (in dollars per share)	$ (1.00)	$ (0.54)

XML

Net Loss Per Share - Antidilutive Securities (Details) - shares shares in Thousands	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Anti-dilutive securities excluded from computation of earnings per share amount	15,672	4,963
Shares subject to outstanding stock options
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Anti-dilutive securities excluded from computation of earnings per share amount	5,476	4,450
Shares subject to outstanding restricted stock units
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Anti-dilutive securities excluded from computation of earnings per share amount	738	485
Shares subject to outstanding warrants to purchase common stock
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Anti-dilutive securities excluded from computation of earnings per share amount	28	28
Shares issuable upon conversion of Notes
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Anti-dilutive securities excluded from computation of earnings per share amount	9,430	0

XML

United Kingdom (U.K.) Research and Development (R&D) Tax Relief Scheme (Details) - USD ($) $ in Millions	1 Months Ended	3 Months Ended
	Dec. 31, 2019	Mar. 31, 2021	Mar. 31, 2020
U.K. tax legislation | U.K. tax legislation
Operating Loss Carryforwards [Line Items]
Window to seek relief under U.K. tax legislature		2 years
Tax year 2017
Operating Loss Carryforwards [Line Items]
Claim for refundable cash credit	$ 9.9
Proceeds from claims	9.9
Tax year 2018
Operating Loss Carryforwards [Line Items]
Claim for refundable cash credit	9.8
Proceeds from claims	$ 9.8
2017 and 2018 tax year claims
Operating Loss Carryforwards [Line Items]
Other income			$ 19.7