UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

WASHINGTON, D.C. 20549

FORM 10-Q

(Mark One)

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

For the Quarterly Period Ended September 30, 2012

OR

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

Commission File Number 0-26483

diaDexus, Inc.

(Exact name of Registrant as Specified in its Charter)

Delaware	94-3236309
(State or other jurisdiction of incorporation or organization)	(I.R.S. Employer Identification No.)
349 Oyster Point Boulevard South San Francisco, California	94080
(Address of principal executive offices)	(Zip Code)

(650) 246-6400

(Registrant’s telephone number, including area code)

Indicate by check mark whether the issuer (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  x    No  ¨

Indicate by check mark whether the registrant has submitted electronically and posted on its corporate website, if any, every Interactive Data File required to be submitted and posted 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 and post such files).    Yes  x    No  ¨

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

Large accelerated filer	¨	Accelerated filer	¨
Non-accelerated filer	¨  (Do not check if a smaller reporting company)	Smaller reporting company	x

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

The number of shares outstanding of the registrant’s common stock, $0.01 par value per share, was 53,313,039, as of November 2, 2012.

DIADEXUS, INC.

FORM 10-Q FOR THE QUARTER ENDED SEPTEMBER 30, 2012

TABLE OF CONTENTS

PART I – FINANCIAL INFORMATION
Item 1.	Financial Statements (Unaudited)
	Condensed Balance Sheets	3
	Condensed Statements of Comprehensive Loss	4
	Condensed Statements of Cash Flows	5
	Notes to Condensed Financial Statements	6
Item 2.	Management’s Discussion and Analysis of Financial Condition and Results of Operations	17
Item 3.	Quantitative and Qualitative Disclosures About Market Risk	23
Item 4	Controls and Procedures	23
PART II – OTHER INFORMATION
Item 1.	Legal Proceedings	25
Item 1A.	Risk Factors	25
Item 2.	Unregistered Sales of Equity Securities and Use of Proceeds	34
Item 3.	Defaults Upon Senior Securities	34
Item 4.	Mine Safety Disclosures	34
Item 5.	Other Information	34
Item 6.	Exhibits	35
Signatures		36

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PART I – FINANCIAL INFORMATION

Item 1. Financial Statements

DIADEXUS, INC.

CONDENSED BALANCE SHEETS

(in thousands, except share data)

	September 30, 2012			December 31, 2011
	(unaudited)			(Note 1)
Assets
Current assets:
Cash and cash equivalents	$	12,955		$	10,484
Short-term investment securities		996			6,492
Accounts receivable, net of allowance for doubtful accounts of $0 and rebate reserve of $0 at September 30, 2012 and $4 and $20, respectively, at December 31, 2011		2,471			2,408
Inventories		199			117
Restricted cash		—			400
Assets held for sale		300			304
Prepaid expenses and other current assets		998			975
Total current assets		17,919			21,180
Long-term investments		—			250
Restricted cash		1,400			1,400
Property and equipment, net		1,263			1,350
Other long-term assets		161			175
Total assets	$	20,743		$	24,355
Liabilities and Stockholders’ Equity
Current liabilities:
Accounts payable	$	311		$	882
Notes payable, current portion		—			372
Deferred revenues, current portion		326			331
Unfavorable lease obligations		563			492
Accrued and other current liabilities		1,934			2,469
Total current liabilities		3,134			4,546
Non-current portion of notes payable		4,883			4,526
Non-current portion of deferred revenue		302			530
Non-current portion of deferred rent		338			266
Non-current portion of unfavorable lease obligation		2,627			3,063
Other long term liabilities		333			284
Total liabilities		11,617			13,215
Commitments and contingencies (Note 14)
Stockholders’ equity:
Preferred Stock, $0.01 par value, 19,979,500 shares authorized; none issued and outstanding		—			—
Common stock, $0.01 par value; 100,000,000 shares authorized; 53,313,039 and 53,067,045 shares issued and outstanding at September 30, 2012 and December 31, 2011, respectively		533			531
Additional paid-in capital		205,928			205,557
Accumulated other comprehensive loss		—			(5	)
Accumulated deficit		(197,335	)		(194,943	)
Total stockholders’ equity		9,126			11,140
Total liabilities and stockholders’ equity	$	20,743		$	24,355

See accompanying notes to condensed financial statements.

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DIADEXUS, INC.

CONDENSED STATEMENTS OF COMPREHENSIVE LOSS

(in thousands, except share data)

	Three Months Ended September 30,						Nine Months  Ended September 30,
	2012			2011			2012			2011
	(unaudited)						(unaudited)
Revenues:
License revenue	$	76		$	76		$	229		$	229
Royalty revenue		279			914			2,353			2,863
Product sales		4,943			3,206			12,775			8,092
Product sales to related party		—			161			—			321
Total revenues		5,298			4,357			15,357			11,505
Operating costs and expenses:
Product costs		1,558			1,439			4,875			3,776
Sales and marketing		1,297			1,207			3,929			3,291
Research and development		912			1,449			3,297			4,215
General and administrative		1,674			2,150			5,354			7,106
Total operating costs and expenses		5,441			6,245			17,455			18,388
Loss from operations		(143	)		(1,888	)		(2,098	)		(6,883	)
Interest income, interest expense and other income (expense), net:
Interest income		3			12			14			44
Interest expense		(99	)		390			(302	)		390
Other income (expense), net		(1	)		9			(4	)		9
Loss before income tax		(240	)		(1,477	)		(2,390	)		(6,440	)
Income tax		1			2			(2	)		(1	)
Net loss	$	(239	)	$	(1,475	)	$	(2,392	)	$	(6,441	)
Basic and diluted net loss per share:	$	—		$	(0.03	)	$	(0.05	)	$	(0.12	)
Weighted average shares used in computing basic and diluted net loss per share		53,215,893			53,067,057			53,117,270			53,067,057
Other comprehensive loss, net of tax:
Net change in unrealized gain/(loss) on available-for-sale securities		1			(2	)		5			(4	)
Comprehensive loss	$	(238	)	$	(1,477	)	$	(2,387	)	$	(6,445	)

See accompanying notes to condensed financial statements.

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DIADEXUS, INC.

CONDENSED STATEMENTS OF CASH FLOWS

(in thousands)

	Nine Months Ended September 30,
	2012			2011
	(unaudited)
Operating activities:
Net loss	$	(2,392	)	$	(6,441	)
Adjustments to reconcile net loss to net cash used in operating activities:
Loss (gain) on disposal of property and equipment and assets held for sale		4			(9	)
Depreciation and amortization		379			407
Stock-based compensation		257			617
Amortization on investments		26			199
Provision for rebate reserve (reversal)		(20	)		36
Provision for doubtful accounts (reversal)		(4	)		—
Noncash other interest (income) expense		21			(379	)
Noncash interest associated with notes payable		99			2
Inventory written off		31			—
Unfavorable lease		(365	)		(269	)
Changes in operating assets and liabilities
Accounts receivable		(39	)		39
Accounts receivable from related party		—			175
Inventory		(113	)		(42	)
Prepaid expenses, other current assets and other long-term assets		3			(62	)
Accounts payable		(493	)		149
Accrued liabilities and other long term liabilities		(340	)		663
Deferred rent		72			78
Deferred revenue		(233	)		(208	)
Net cash used in operating activities		(3,107	)		(5,045	)
Investing activities:
Purchases of property and equipment		(567	)		(278	)
Proceeds from sales of assets		2			13
Restricted cash		400			—
Maturities of available-for-sale investments		6,721			16,527
Purchases of available-for-sale investments		(996	)		(26,505	)
Net cash provided by (used in) investing activities		5,560			(10,243	)
Financing activities:
Net proceeds from notes payable		—			4,980
Proceed from issuance of common stock		68			—
Debt issuance costs		(50	)		(25	)
Net cash provided by financing activities		18			4,955
Net increase (decrease) in cash and cash equivalents		2,471			(10,333	)
Cash and cash equivalents, beginning of period		10,484			20,394
Cash and cash equivalents, end of period	$	12,955		$	10,061
Supplemental disclosure:
Cash paid for interest	$	201		$	—
Net change in accounts payable from acquisition of property and equipment	$	(78	)	$	352
Net change in accrued liabilities from acquisition of property and equipment	$	(195	)	$	139
Issuance of warrants for common stock in connection with debt	$	48		$	94
Debt issuance costs in accounts payable and accrued liabilities	$	—		$	111

See accompanying notes to condensed financial statements.

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diaDexus, Inc.

Notes to Condensed Financial Statements

1. Business Overview

diaDexus, Inc., a Delaware corporation (the “Company”), is a life sciences company focused on developing and commercializing proprietary cardiovascular diagnostic products addressing unmet needs in cardiovascular disease. The Company is the successor to a company initially formed as a joint venture between SmithKlineBeecham Corporation (now GlaxoSmithKline LLC (“GlaxoSmithKline”)) and Incyte Pharmaceuticals, Inc. Upon formation, SmithKlineBeecham Corporation granted the Company an exclusive license to certain diagnostic intellectual property, including Lp-PLA₂, an inflammatory marker of cardiovascular risk.

The Company’s products, PLAC^® Tests, provide information, over and above traditional risk factors, to help identify individuals at increased risk of suffering a heart attack or stroke. Some of these events may be reduced with earlier detection and more aggressive risk-reducing strategies, including treatment to lower LDL-cholesterol goals with statins. The Company has commercialized two PLAC Tests. One test measures the mass of circulating Lp-PLA₂ in the blood, the PLAC Test ELISA Kit. The PLAC Test ELISA Kit is the only blood test cleared by the U.S. Food and Drug Administration (“the FDA”) to aid in assessing risk for both coronary heart disease and ischemic stroke associated with atherosclerosis. The second test, the PLAC Test for Lp-PLA₂ Activity, is an enzyme assay for the quantitative determination of Lp-PLA₂ activity levels in human plasma and serum on automated clinical chemistry analyzers, to be used in conjunction with clinical evaluation and patient risk assessment as an indicator of atherosclerotic cardiovascular disease. The Company is currently commercializing the PLAC Test ELISA Kit in the United States and Europe and the PLAC Test for Lp-PLA₂ Activity in Europe.

The Company has incurred substantial losses since inception and expects to continue to incur net losses for at least the next few years if the Company engages in new development activities to broaden or enhance its product pipeline. To date, the Company has funded its operations primarily through private placements of preferred stock and debt financing, as well as through revenue generated from the sale of products.

In September 2011, the Company entered into a loan and security agreement with Comerica Bank, which was amended in September 2012 (Note 9). This loan contains various covenants. If the Company breaches any of these covenants or is unable to make a required payment of principal or interest, or experiences a material adverse change to its business, it could result in a default under the loan. Additionally, the Company is required to achieve revenues equal to at least 80% of monthly projections approved by its Board of Directors and provided to the bank, and failure to do so could result in a default under the loan. Upon the occurrence of an event of default under the loan, the bank could elect to declare all amounts outstanding to be immediately due and payable. If the Company is unable to repay those amounts, the bank could proceed against the collateral granted to them to secure such indebtedness. The Company has pledged substantially all of its assets, other than its intellectual property, as collateral under the loan. The Company’s future liquidity requirements may increase beyond currently expected levels if it fails to maintain compliance with its covenants. In order to meet the future liquidity needs, the Company may become reliant on additional equity and/or debt financing. Additional funding may not be available when needed or on terms acceptable to the Company. Any additional equity financing may be dilutive to stockholders, and debt financing, if available, may involve restrictive covenants. The Company cannot assure you that it will be able to raise any such additional funding.

PLAC Test ELISA Kit

The Company introduced its initial PLAC Test ELISA Kit product in 2004. The PLAC Test ELISA Kit uses microplate technologies to measure levels of Lp-PLA₂. The infrastructure for performing microplate tests typically exists only at large and midsize clinical reference laboratories and large hospitals, which must be certified by the US Department of Health and Human Services (“DHHS”) for high-complexity diagnostics under the Clinical Laboratory Improvement Amendments (“CLIA”). Smaller hospitals and clinics can order the PLAC Test ELISA Kit for their patients from those institutions that are able to perform microplate tests and offer the PLAC Test ELISA Kit. Patients can have their blood drawn at a local laboratory and shipped to the more advanced institutions for analysis. The PLAC Test ELISA Kit is the only product the Company markets in both the United States and Europe.

PLAC Test for Lp-PLA₂ Activity

The Company introduced the PLAC Test for Lp-PLA₂ Activity in Europe in March 2012. This PLAC Test for Lp-PLA₂ Activity is an enzyme assay for the quantitative determination of Lp-PLA₂ activity levels in human serum or plasma. The PLAC Test for Lp-PLA₂ Activity allows for the measurement of Lp-PLA₂ using automated clinical chemistry analyzer technology. This clinical chemistry technology is more prevalent than the microplate technology used for the PLAC Test

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ELISA Kit and is less difficult to operate, such that a broader array of institutions can conduct the test. This group includes clinical laboratories and hospitals of all sizes. In addition, the sample handling requirements are much less stringent for the PLAC Test for Lp-PLA₂ Activity compared to the PLAC Test ELISA Kit, allowing greater ease of use for those facilities processing specimens. The PLAC Test for Lp-PLA₂ Activity is currently available in Europe for use in conjunction with clinical evaluation and patient risk assessment as an indicator of atherosclerotic cardiovascular disease. The Company affixed the CE marking for this intended use by self-certification in January 2012. The PLAC Test for Lp-PLA₂ Activity is available on a commercial basis only in Europe. The Company plans to pursue 510(k) clearance for this test from the FDA and eventually commercialize this assay format in the United States if the Company obtains FDA clearance.

All references in these notes to condensed financial statements to the “Company,” “we,” “us” and “our” refer to diaDexus, Inc. (f/k/a VaxGen, Inc.), a Delaware corporation, unless the context requires otherwise.

Basis of Presentation

The accompanying unaudited condensed financial statements have been prepared in accordance with U.S. generally accepted accounting principles (“GAAP”) for interim financial information and with the instructions to Form 10-Q and Article 10 of Regulation S-X. The year-end condensed balance sheet data was derived from audited financial statements, but does not include all disclosures required by U.S. GAAP. In the opinion of management, the accompanying unaudited condensed financial statements have been prepared on a consistent basis with December 31, 2011 audited financial statements and includes all adjustments, consisting of normal recurring adjustments, which are necessary to fairly state the Company’s financial position as of September 30, 2012 and results of operations and cash flows for both the three and nine months ended September 30, 2012.

2. Summary of Significant Accounting Policies

The Company’s significant accounting policies are disclosed in the Company’s annual report on Form 10-K for the year ended December 31, 2011, filed with the SEC on March 15, 2012, and have not changed as of September 30, 2012.

Recent Accounting Pronouncements

In December 2011, the Financial Accounting Standards Board (“FASB”) issued Accounting Standards Update (“ASU”) No. 2011-11, “Disclosure about Offsetting Assets and Liabilities.” ASU 2011-11 will require the Company to disclose information about offsetting and related arrangements to enable users of its financial statements to understand the effect of those arrangements on its financial positions. The new guidance is effective for annual reporting periods beginning on or after January 1, 2013, and interim periods within those annual periods. The disclosures are to be applied retroactively for all comparative periods presented. The Company does not expect that this guidance will have an impact on its financial position, results of operations or cash flows as it is disclosure-only in nature.

In May 2011, the FASB amended its guidance to converge fair value measurement and disclosure guidance about fair value measurement under U.S. GAAP with International Financial Reporting Standards (“IFRS”). IFRS is a comprehensive series of accounting standards published by the International Accounting Standard Board. The amendment changes the wording used to describe many of the requirements in the U.S. GAAP for measuring fair value and for disclosing information about fair value measurements. For many of the requirements, the FASB does not intend for the amendment to result in a change in the application of the requirements in the current authoritative guidance. The amendment became effective prospectively for the Company’s interim period ended March 31, 2012. The Company adopted this guidance and the adoption did not have a material impact on the Company’s financial positions, results of operations or cash flows.

In June 2011, the FASB issued a new standard on the presentation of comprehensive income. The new standard eliminated the alternative to report other comprehensive income and its components in the statement of changes in equity. Under the new standard, companies can elect to present items of net income and other comprehensive income in one continuous statement or in two separate, but consecutive statements. We adopted the provisions of this guidance during the first quarter 2012.

3. Cash, Cash Equivalents and Investments

As part of its cash management program, the Company maintains a portfolio of marketable investment securities. The securities are investment grade and generally mature within one year and may include tax exempt securities and certificates of deposit. The fair value of substantially all securities is determined by quoted market prices. The Company maintains its cash in bank accounts, which at times may exceed federally insured limits. The Company has not experienced any losses on such accounts. The Company considers all highly liquid investments purchased with an original maturity of three months or less at the time of purchase to be cash equivalents.

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The following is a summary of cash, cash equivalents, and available-for-sale securities at September 30, 2012 and December 31, 2011 (in thousands):

	September 30, 2012
	Cost Basis		Unrealized Gains		Unrealized Losses		Estimated Fair Value
Cash and cash equivalents:
Cash	$	6,408	$	—	$	—	$	6,408
Money market funds		6,547		—		—		6,547
Total cash and cash equivalents	$	12,955	$	—	$	—	$	12,955
Available-for-sale marketable securities:
Certificates of deposit		996		—		—		996
Total available-for-sale marketable securities	$	996	$	—	$	—	$	996

	December 31, 2011
	Cost Basis		Unrealized Gains		Unrealized Losses			Estimated Fair Value
Cash and cash equivalents:
Cash	$	3,243	$	—	$	—		$	3,243
Money market funds		7,241		—		—			7,241
Total cash and cash equivalents	$	10,484	$	—	$	—		$	10,484
Available-for-sale marketable securities:
Commercial paper		3,147		—		(1	)		3,146
Corporate notes		2,850		—		(4	)		2,846
US government agency obligations		750		—		—			750
Total available-for-sale marketable securities	$	6,747	$	—	$	(5	)	$	6,742

Fair Value Measurements

In accordance with ASC 820, the Company discloses and recognizes the fair value of its assets and liabilities using a hierarchy that prioritizes the inputs to valuation techniques used to measure fair value. The guidance establishes three levels of the fair value hierarchy as follows:

Level 1: Observable inputs, such as quoted prices in active markets for identical assets or liabilities;

Level 2: Observable inputs other than Level 1 prices, such as quoted prices for similar assets or liabilities, quoted prices in markets that are not active, or other inputs that are observable or can be corroborated by observable market data for substantially the full term of the assets or liabilities;

Level 3: Unobservable inputs that are supported by little or no market activity and that are significant to the fair value of the assets or liabilities.

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The following table represents the Company’s fair value hierarchy for its financial assets (cash equivalents and investments) measured at fair value on a recurring basis as of September 30, 2012 and December 31, 2011 (in thousands):

			Fair Value Measurements
	Balance at September  30, 2012		Quoted Prices In  Active Markets for Identical  Assets Level 1		Significant other Observable Inputs Level 2		Significant Unobservable Inputs Level 3
Assets:
Cash	$	6,408	$	6,408	$	—	$	—
Money market funds		6,547		6,547		—		—
Certificates of deposit		996		—		996		—
Restricted cash		1,400		—		1,400		—
	$	15,351	$	12,955	$	2,396	$	—

			Fair Value Measurements
	Balance as of December  31, 2011		Quoted Prices In  Active Markets for Identical  Assets Level 1		Significant other Observable Inputs Level 2		Significant Unobservable Inputs Level 3
Assets:
Cash	$	3,243	$	3,243	$	—	$	—
Money market funds		7,241		7,241		—		—
Commercial paper		3,146		—		3,146		—
Corporate notes		2,846		—		2,846		—
US government agency obligations		750		—		750		—
Restricted cash		1,800		—		1,800		—
	$	19,026	$	10,484	$	8,542	$	—

The fair value of the notes payable is valued based on Level 2 inputs and approximates its book value. The fair value of the notes payable is based on the present value of expected future cash flows and assumptions about current interest rates and the credit worthiness of the Company. As of September 30, 2012, the notes payable is carried at face value of $5.0 million less any unamortized debt discount.

The carrying value of other financial instruments, including cash, accounts receivable, accounts payable and other payables, approximates fair value due to their short maturities.

4. Inventory

Inventory consists of the following (in thousands):

	September 30, 2012		December 31, 2011
Finished goods	$	180	$	71
Raw materials		19		46
	$	199	$	117

5. Assets Held For Sale

Prior to the period reflected in this report, the Company had committed to a plan to sell the equipment related to its manufacturing facility and had determined that these assets met the criteria for, and had been classified as, “held for sale” in accordance with ASC Topic 360. The market approach was used in determining the fair market value of these assets.

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Total assets held for sale as of September 30, 2012 and December 31, 2011 is as follows (in thousands):

			Fair Value Measurements
Description	Carrying Value at September 30, 2012		September 30, 2012		Quoted Prices in Active Markets for Identical Assets (Level 1)		Significant Other Observable Inputs (Level 2)		Significant Unobservable Inputs (Level 3)		Nine Months Ended September 30, 2012 Total Gains (Losses)
Assets held for sale	$	300	$	695	$	—	$	—	$	695	$	(2	)

			Fair Value Measurements
Description	December 31, 2011		Quoted Prices in Active Markets for Identical Assets (Level 1)		Significant Other Observable Inputs (Level 2)		Significant Unobservable Inputs (Level 3)		Year Ended December 31, 2011 Total Gains (Losses)
Assets held for sale	$	304	$	—	$	—	$	304	$	—

The measurement of the assets held for sale fair value incorporated significant unobservable inputs as a result of a lack of any available observable market information to determine the fair value. The calculation of the fair value of assets held for sale used a market valuation technique that relied on Level 3 inputs, including quoted prices for similar assets. The Company is committed to selling these assets and signed an agreement to sell the assets for $695,000, net of disposal costs. Any gain or loss resulting from the sale of the assets held for sale at September 30, 2012 will be included in the statement of comprehensive loss.

6. Property, Plant and Equipment

Property and equipment are recorded at cost. Expenditures for major additions and improvements are capitalized, and maintenance and repairs are charged to expense as incurred. When property and equipment are retired or otherwise disposed of, the cost and accumulated depreciation are removed from the accounts and any resulting gain or loss is included in the results of operations for the respective period. Depreciation is provided over the estimated useful lives of the related assets using the straight-line method for financial statement purposes. The Company uses other depreciation methods for tax purposes where appropriate. The estimated useful lives for significant property and equipment categories are as follows:

Office and Laboratory equipment	3 years
Computer equipment and software	3 years
Leasehold improvements	Term of lease agreement

The following is a summary of property and equipment at cost less accumulated depreciation as of September 30, 2012 and December 31, 2011 (in thousands):

	September 30, 2012			December 31, 2011
Laboratory equipment	$	3,083		$	5,202
Leasehold improvements		602			8,283
Computer and software		334			1,916
Furniture and fixtures		163			835
		4,182			16,236
Less: Accumulated depreciation and amortization		(2,919	)		(14,886	)
	$	1,263		$	1,350

Depreciation and amortization expense was $0.1 million and $0.4 million for the three and nine months ended September 30, 2012, respectively, and $0.1 million and $0.4 million, respectively, for the same periods in 2011.

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7. Total Accrued and Other Current Liabilities

Total accrued and other current liabilities include the following as of September 30, 2012 and December 31, 2011 (in thousands):

	September 30, 2012		December 31, 2011
Accrued payroll and related expenses	$	1,011	$	1,351
Accrued royalty expense		171		207
Accrued sales tax		65		126
Accrued legal and patent expense		166		35
Accrued consulting expenses		73		69
Property and equipment		5		200
Accrued audit fees		—		120
Accrued collaborative research obligations		18		96
Other current liabilities		425		265
Total accrued and other current liabilities	$	1,934	$	2,469

8. Concentration of Credit Risk

Revenues from the following customers represented a significant portion of total revenue for the three and nine months ended September 30, 2012 and 2011 and accounts receivable as of September 30, 2012 and December 31, 2011:

	Revenue												Accounts Receivable
	Three Months Ended September  30,						Nine Months Ended September  30,						September 30,			December 31,
	2012			2011			2012			2011			2012			2011
Customer A		44	%		45	%		45	%		28	%		31	%		44	%
Customer B		15	%		10	%		13	%		10	%		23	%		13	%
Customer C		6	%		—	%		6	%		—	%		9	%		—	%
Customer D		6	%		—	%		4	%		—	%		9	%		—	%
Customer E		—	%		20	%		—	%		30	%		—	%		20	%
Customer F		—	%		9	%		4	%		12	%		—	%		15	%
Total		71	%		84	%		72	%		80	%		72	%		92	%

9. Notes Payable

In September 2011, the Company entered into a loan and security agreement with Comerica Bank to borrow up to $5,000,000, the entire amount of which was borrowed at a rate of 5.25% per annum. The loan was payable in 36 monthly installments which were to begin in October 2012, with interest only payments being made from October 2011 to September 2012. The Company paid an initial fee of $25,000 for access to this loan and will be required to pay an additional fee of $100,000 following repayment of the loan. The Company may prepay all, but not less than all, of the loaned amount with 30 days advance notice to the bank. In connection with the loan, the Company issued a warrant to the bank to purchase 480,769 shares of the Company’s common stock (Note 13).

The term loan is secured by a first priority security interest on all of the Company’s assets excluding the Company’s intellectual property (except for rights to payment related to the sale, licensing or disposition of such intellectual property rights) and property not assignable without consent by a third party or with respect to which granting a security interest is contrary to law. In addition, the Company has agreed not to sell, assign, transfer, pledge or otherwise encumber its intellectual property to another entity without the bank’s approval or consent, subject to certain exceptions.

The loan and security agreement contains customary representations and warranties, covenants, events of defaults and termination provisions. The affirmative covenants include, among other things, that the Company timely file taxes, maintain good standing and government compliance, achieve at least 80% of specified monthly revenue projections calculated on a trailing three months basis, maintain primary depository and operating accounts with the bank, maintain liability and other insurance, and provide security interests to the bank in the collateral of any subsidiary formed or acquired by the Company in the future. The negative covenants provide, among other things, that without the prior consent of the bank, the Company may not dispose of certain assets, engage in certain business combinations or acquisitions, incur additional indebtedness or

11

encumber any of the Company’s property (subject to certain exceptions), pay dividends on the Company’s capital stock or make prohibited investments. The loan and security agreement provides that an event of default will occur if, among other triggers, (1) the Company defaults in the payment of any amount payable under the agreement when due, (2) there occurs any circumstance or circumstances that could reasonably be expected to result in a material adverse effect on the Company’s business, operations or condition, or on the Company’s ability to perform its obligations under the agreement, (3) the Company becomes insolvent, (4) the Company undergoes a change in control or (5) the Company breaches any negative covenants or certain affirmative covenants in the agreement or, subject to a cure period, otherwise neglects to perform or observe any material item in the agreement. The repayment of the term loan may be accelerated, at the option of the bank, following the occurrence of an event of default, which would require the Company to pay to the bank an amount equal to the sum of: (i) all outstanding principal plus accrued interest, (ii) the final payment, plus (iii) all other sums, that shall have become due and payable but have not been paid, including interest at the default rate with respect to any past due amounts. As of September 30, 2012, the Company was in compliance with all the covenants.

On September 11, 2012, the Company and Comerica Bank entered into an Amended and Restated Loan and Security Agreement (the “Amendment”). The Amendment extends the interest-only payment period for an additional twelve months, through September 23, 2013, and extends the maturity date for an additional twelve months, to September 23, 2016. The Amendment also reduces the monthly principal payments by amortizing the loan over a 48 month basis, resulting in an increased balloon payment of principal on the maturity date. The Company paid a fee of $50,000 for access to the Amendment. Pursuant to the Amendment, the Company issued a warrant to Comerica to purchase 168,919 shares of its common stock. The warrant has an exercise price of $0.37 per share and will expire on September 11, 2019 (Note 13).

The Company accounted for this amendment as a debt modification since the terms of the original and the amended Loan and Security Agreements were not substantially different, and the present value of cash flows of the modified instrument was within 10% of the cash flows of the original debt instrument. Accordingly, debt discount of $48,000 associated with the Amended Loan and security Agreement, and unamortized debt discount of $72,000 from the Original Term Loan will be amortized as an adjustment of interest expense over the term of the Amended Loan and Security Agreement using the effective interest method.

Future minimum payments for the notes payable are as follows (in thousands):

2012 (remainder of year)	$	66
2013		574
2014		1,466
2015		1,400
2016		2,357
Total minimum payments		5,863
Less: Amount representing interest		(863	)
Present value of minimum payments		5,000
Less: Unamortized debt discount		(117	)
Notes payable, net		4,883
Less: Notes payable, current portion		—
Non-current portion of notes payable	$	4,883

10. Common Stock

On July 15, 2011, the Company amended its certificate of incorporation to increase the number of authorized shares of its common stock, par value of $0.01 per share, to 100,000,000. The holders of common stock are entitled to receive dividends, as, when and if declared by the Company’s Board of Directors out of funds legally available for distribution, subject to the restriction on dividends contained in the Company’s loan agreement with a bank (Note 9).

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11. Basic and Diluted Net Loss per Share

Basic net loss per common share is based on the weighted average number of common shares outstanding during the period. Diluted net loss per common share is based on the weighted average number of common shares and other dilutive securities outstanding during the period, provided that including these dilutive securities does not increase the net loss per share.

The effect of the options and warrants was anti-dilutive for the three and nine months ended September 30, 2012 and 2011. The following table shows the total outstanding securities considered anti-dilutive and therefore, excluded from the computation of diluted net loss per share (in thousands):

	As of September 30,
	2012		2011
Options to purchase common stock		11,025		8,528
Warrants to purchase common stock		650		485
Total		11,675		9,013

12. Stock Based Compensation

Stock Option Plans

2012 Equity Incentive Award Plan

The Company’s stockholders approved the 2012 Equity Incentive Award Plan (the “2012 Plan”) at the 2012 Annual Meeting of Stockholders on May 17, 2012 and approved 3,000,000 shares of common stock authorized for issuance. On May 17, 2012, all stock options that were issued and issuable in the 1996 Plan, the Director Plan and outside of plans were transferred to the 2012 Plan. Options granted under the 2012 Plan may be designated as qualified or nonqualified at the discretion of the Compensation Committee of the Board of Directors. Generally, shares issuable upon exercise of options vest ratably over four years, beginning one year from the date of grant; however, options can vest upon grant. Option terms expire no later than 10 years from the date of grant, or 5 years from the date the option is granted to a greater than 10% stockholder. The stock options are exercisable at not less than the fair market value of the stock at the date of grant, or not less than 110% of the fair market value of the stock at the date of grant if granted to a greater than 10% stockholder. As of September 30, 2012, options for 11,025,348 shares were outstanding and 3,733,054 shares were available for grant under the 2012 Plan.

1996 Stock Option Plan

The 1996 Stock Option Plan (the “1996 Plan”) initially had 4,750,000 shares of common stock authorized for issuance and a provision that automatically increased this number by 3.5% of the issued and outstanding common stock on the last trading day of the December immediately preceding each fiscal year through January 2007. Options granted under the 1996 Plan were designated as qualified or nonqualified at the discretion of the Compensation Committee of the Board of Directors. Generally, shares issuable upon exercise of options vest ratably over four years, beginning one year from the date of grant; however, options could vest upon grant. All options expire no later than 10 years from the date of grant. Qualified stock options are exercisable at not less than the fair market value of the stock at the date of grant, and nonqualified stock options are exercisable at prices determined at the discretion of the Board of Directors, but not less than 85% of the fair market value of the stock at the date of grant. On May 17, 2012, 6,398,904 shares that were subject to awards under this plan and 1,555,492 shares which were available for issuance under this plan were transferred to the 2012 Equity Incentive Award Plan.

1998 Director Stock Option Plan

The 1998 Director Stock Option Plan (the “Director Plan”) for non-employee directors had 300,000 shares of common stock authorized for issuance. On May 17, 2012, 170,000 shares that were subject to awards under this plan and 130,000 shares which were available for issuance under this plan were transferred to the 2012 Equity Incentive Award Plan upon stockholder approval.

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The following table summarizes stock compensation expense related to employee stock options and employee stock based compensation for the three and nine months ended September 30, 2012 and 2011, which was incurred as follows (in thousands)

	Three Months Ended September 30,				Nine Months Ended September 30,
	2012		2011		2012		2011
Stock compensation expense:
Product costs	$	3	$	1	$	8	$	7
Research and development		19		38		50		81
Sales and marketing		19		14		48		40
General and administrative		52		102		151		489
Total stock compensation expense	$	93	$	155	$	257	$	617

Stock based compensation expense recognized during the three and nine months ended September 30, 2012 and 2011 includes compensation expense for stock based awards granted to employees based on the grant date fair value estimated in accordance with the provisions of ASC 718. As of September 30, 2012, the total remaining unrecognized cost was approximately $0.9 million to be recognized over approximately three years.

Valuation Assumptions

The compensation expense related to stock options recognized was determined using the Black-Scholes option valuation model. Option valuation models require the input of subjective assumptions and these assumptions can vary over time. The weighted average assumptions used were as follows:

	Three Months Ended September 30,						Nine Months Ended September 30,
	2012			2011			2012			2011
Dividend yield		0.0	%		0.0	%		0.0	%		0.0	%
Risk-free interest rate		0.58	%		0.64	%		0.54	%		0.75	%
Expected volatility		95.47	%		93.93	%		95.98	%		93.50	%
Forfeiture rate		13.24	%		11.57	%		13.24	%		11.57	%
Expected term (years)		4.12			4.27			4.12			4.27
Fair value per share at grant date	$	0.22		$	0.18		$	0.21			$0.19

The expected stock price volatility assumption was determined by examining the historical volatilities for industry peers, as the Company did not have sufficient trading history for the Company’s common stock. The Company will continue to analyze the historical stock price volatility and expected term assumption as more historical data for the Company’s common stock becomes available. The risk-free interest rate assumption is based on the U.S. Treasury instruments whose term was consistent with the expected term of the Company’s stock options. The expected dividend assumption is based on the Company’s history and expectation of dividend payouts. Different estimates of volatility and expected term could materially change the value of an option and the resulting expense. The expected term of stock option represents the weighted-average period the stock options are expected to remain outstanding and is based on the options vesting terms, contractual terms and historical information to develop reasonable expectations about future exercise patterns and post-vesting employment termination behavior.

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Employee Stock-Based Compensation

The table below presents information related to stock option activity for the nine months ended September 30, 2012, as follows:

	Number of Options Outstanding			Weighted- Average Exercise Price		Weighted- Average Remaining Contractual Term (In years)		Aggregate Intrinsic Value
Outstanding at December 31, 2011		9,187,589		$	0.48
Options granted		2,663,190			0.32
Options exercised		(245,994	)		0.27
Options cancelled/forfeited/expired		(579,437	)		0.78
Outstanding at September 30, 2012		11,025,348		$	0.43		6.93	$	684,154
Exercisable at September 30, 2012		5,200,714		$	0.59		4.42	$	358,428
Vested and expected to vest at September 30, 2012		10,051,660		$	0.44		6.71	$	632,964

13. Stock Warrants

The Company issues warrants to investors as part of its overall financing strategy and to vendors in order to reduce costs. In connection with the loan and security agreement the Company entered into with Comerica bank (Note 9) in September 2011, the Company issued a warrant to purchase 480,769 shares of the Company’s common stock, at an exercise price of $0.26 per share. The warrant expires in September 2018. The initial fair value of the warrant was calculated using the Black-Scholes option pricing model and the following assumptions: volatility of 88.03%, risk-free interest rate of 1.36%, exercise price of $0.26 and an expected life of 7 years. The fair value of the warrant was determined to be $94,000 and was recorded as equity in additional paid-in-capital and a discount to the carrying value of the loan. Through August 2012, the discount was amortized to interest expense using the effective interest rate method over the 48-month term of the original loan. As of September 2012, and in connection with the Amended and Restated Loan and Security Agreement between the Company and Comerica Bank (the “Amendment”, Note 9), the unamortized discount will be recognized over the remaining term of the amended loan, which matures in September 2016.

In connection with the Amendment the Company issued a warrant to purchase 168,919 shares of the Company’s common stock, at an exercise price of $0.37 per share. This warrant expires in September 2019. The initial fair value of the warrant was calculated using the Black-Scholes option pricing model and the following assumptions: volatility of 89.87%, risk-free interest rate of 1.03%, exercise price of $0.37 and an expected life of 7 years. The fair value of the warrant was determined to be $48,000 and was recorded as equity in additional paid-in-capital and a discount to the carrying value of the loan. The discount is being amortized to interest expense using the effective interest rate method over the remaining term of the amended loan which matures in September 2016.

As of September 30, 2012, there were warrants outstanding to purchase 649,688 shares of the Company’s common stock, with a weighted-average exercise price of $0.29 per share and an aggregate exercise price of $0.2 million.

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The following table summarizes information about all warrants outstanding as of September 30, 2012:

	Warrants Outstanding						Warrants Exercisable
Exercise Price	Number Outstanding		Weighted Average Remaining Contractual Life (In Years)		Weighted Average Exercise Price		Number Exercisable		Weighted Average Exercise Price
$0.26		480,769		5.98	$	0.26		480,769	$	0.26
$0.37		168,919		6.98	$	0.37		168,919	$	0.37
		649,688		6.24	$	0.29		649,688	$	0.29

14. Leases, Commitments and Contingencies

The Company leases an office and laboratory facility (the “349 Facility”) under a long-term, non-cancelable operating lease agreement, which expires in December 2016. The Company also leased another office and laboratory facility (the “343 Facility”), and subleased a portion of that facility, until the Company’s underlying lease for that facility expired on January 1, 2012. Upon expiration of the 343 Facility lease, restricted cash of $400,000 previously pledged as security for this lease was released.

In 2010, the Company recorded a lease obligation associated with the 349 Facility, which contained a lease payment that exceeded current market rates. Accordingly, the Company recognized a $4.1 million unfavorable lease obligation, included in the accompanying balance sheet. The Company amortizes the unfavorable lease obligation using the effective interest rate method.

Rent expense for the Company’s facilities was $508,000 and $1.5 million for the three and nine months ended September 30, 2012, respectively, and $798,000 and $2.3 million, respectively, for the same periods in 2011. The terms of the lease for the 349 Facility provides for rental payments on a graduated scale. The Company recognizes rent expense on a straight-line basis over the lease period. Deferred rent of $338,000 and $266,000 as of September 30, 2012 and December 31, 2011, respectively, is included in the accompanying balance sheet.

Rental income from the sublease of the 343 Facility was $0 for both the three and nine months ended September 30, 2012 and $151,000 and $809,000, respectively, for the same periods in 2011. This rental income has been included as a reduction to operating expenses for the three and nine months ended September 30, 2011 in the statements of comprehensive income.

Future minimum lease payments under non-cancelable operating leases are as follows (in thousands):

	Operating Leases
2012 (remainder of year)	$	608
2013		2,505
2014		2,581
2015		2,658
2016		2,738
Total minimum lease payments	$	11,090

15. Income Taxes

Provision for Income Tax

The Company’s effective tax rate is 0% for income tax for the nine months ended September 30, 2012 and the Company expects that its effective tax rate for the full year 2012 will be 0%. Based on the weight of available evidence, including cumulative losses since inception and expected future losses, the Company has determined that it is more likely than not that the deferred tax asset amount will not be realized and therefore a valuation allowance has been provided on net deferred tax assets.

Under the provisions of Section 382 and 383 of the Internal Revenue Code, a change of control, as defined, may impose an annual limitation on the amount of the Company’s net operating loss and tax credit carryforwards, and other tax attributes, that can be used to reduce future tax liabilities. As a result of the Reverse Merger, certain of the Company’s Old diaDexus tax attributes prior to the Reverse Merger are subject to an annual limitation of $240,000 for federal and state purposes.

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The Company files U.S. Federal and multiple state tax returns. The Company is currently not subject to any income tax examinations. Due to the Company’s losses, generally all years remain open.

Uncertain Tax Positions

Effective January 1, 2009, the Company adopted ASC 740-10, which requires that the Company recognize the financial statement effects of a tax position when it becomes more likely than not, based upon the technical merits, that the position will be sustained upon examination.

The gross amount of unrecognized tax benefits as of September 30, 2012 is $1.4 million related to the reserve on R&D credits, none of which will affect the effective tax rate if recognized due to the valuation allowance. The Company does not expect any material changes in the next 12 months in unrecognized tax benefits.

The Company recognizes interest and/or penalties related to uncertain tax positions. To the extent accrued interest and penalties do not ultimately become payable, amounts accrued will be reduced and reflected in the period that such determination is made. The interest and penalties are recognized as other expense and not tax expense. The Company currently has no interest and penalties related to uncertain tax positions.

16. Subsequent Events

None

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

The following Management’s Discussion and Analysis of Financial Condition and Results of Operations contains forward-looking statements that involve a number of risks and uncertainties. Our actual results could differ materially from those indicated by forward-looking statements as a result of various factors, including but not limited to, the period for which we estimate our cash resources are sufficient, the availability of additional funds, as well as those set forth under “Risk Factors” and those that may be identified from time to time in our reports and registration statements filed with the Securities and Exchange Commission.

The following discussion and analysis is intended to provide an investor with a narrative of our financial results and an evaluation of our financial condition and results of operations. This discussion should be read in conjunction with the unaudited Condensed Financial Statements and related Notes included in Item 1 of this Quarterly Report and the Consolidated Financial Statements and related Notes and Management’s Discussion and Analysis of Financial Condition and Results of Operations contained in our Annual Report on Form 10-K for the year ended December 31, 2011.

Overview

We are a life sciences company developing and commercializing proprietary cardiovascular diagnostic products addressing unmet needs in cardiovascular disease. We are the successor to a company initially formed as a joint venture between SmithKlineBeecham Corporation (now GlaxoSmithKline LLC (“GlaxoSmithKline”)) and Incyte Pharmaceuticals, Inc. Upon formation, SmithKlineBeecham Corporation granted us an exclusive license to certain diagnostic intellectual property, including Lp-PLA₂, an inflammatory marker of cardiovascular risk.

Our products, known as PLAC^® Tests, provide information, over and above traditional risk factors, to help identify individuals at increased risk of suffering a heart attack or stroke. Some of these events may be reduced with earlier detection and more aggressive risk-reducing strategies, including treatment to lower LDL-cholesterol goals with statins. We have commercialized two PLAC Tests. One test measures the mass of circulating Lp-PLA₂ in the blood, the PLAC Test ELISA Kit. The PLAC Test ELISA Kit is the only blood test cleared by the FDA to aid in assessing risk for both coronary heart disease and ischemic stroke associated with atherosclerosis. The second test, the PLAC Test for Lp-PLA₂ Activity, is an enzyme assay for the quantitative determination of Lp-PLA₂ activity levels in human plasma and serum on automated clinical chemistry analyzers, to be used in conjunction with clinical evaluation and patient risk assessment as an indicator of atherosclerotic cardiovascular disease. We are currently commercializing the PLAC Test ELISA Kit in the United States and Europe and the PLAC Test for Lp-PLA₂ Activity in Europe.

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We have incurred substantial losses since inception, and expect to continue to incur net losses for at least the next few years if the Company engages in new development activities to broaden or enhance its product pipeline. To date, we have funded our operations primarily through private placements of preferred stock and debt financing, as well as through revenue generated from the sale of products.

We entered into a loan agreement with a bank in September 2011, which was amended in September 2012. The agreement contains certain financial and non-financial covenants. Our future liquidity requirements may increase beyond currently expected levels if we fail to maintain compliance with such covenants. In order to meet our future liquidity needs, we may become reliant on additional equity and/or debt financing. Additional funding may not be available when needed or on terms acceptable to us. Any additional equity financing may be dilutive to stockholders, and debt financing, if available, may involve restrictive covenants. We cannot assure you that we will be able to raise any such additional funding.

All references in this Quarterly Report on Form 10-Q to the “Company,” “we,” “us” and “our” refer to diaDexus, Inc. (f/k/a VaxGen, Inc.), a Delaware corporation, unless the context requires otherwise.

Critical Accounting Policies and Estimates

The accompanying discussion and analysis of our financial condition and results of operations is based upon our financial statements, which have been prepared in accordance with accounting principles generally accepted in the United States (“GAAP”). The preparation of these financial statements requires management to make estimates and judgments that affect the reported amounts of assets, liabilities and expenses, and related disclosures. On an ongoing basis, we evaluate these estimates. Estimates are based on historical experience, information received from third parties and on various other assumptions that are believed to be reasonable under the circumstances, the results of which form the basis for making judgments about the carrying values of assets and liabilities that are not readily apparent from other sources. Actual results could therefore differ materially from those estimates under different assumptions or conditions.

Critical accounting estimates, as defined by the Securities and Exchange Commission (“SEC”), are those that are most important to the portrayal of our financial condition and results of operations and require our management’s most difficult and subjective judgments and estimates of matters that are inherently uncertain. The accounting policies and estimates that we consider to be critical, subjective, and requiring judgment in their application are summarized in “Item 7—Management’s Discussion and Analysis of Financial Condition and Results of Operations” in our Annual Report on Form 10-K for the year ended December 31, 2011 filed with SEC on March 15, 2012. There have been no significant changes to the accounting policies and estimates disclosed in our Form 10-K.

Results of Operations

For the Three and Nine Months Ended September 30, 2012 and 2011.

Revenues

	Three Months Ended September 30,				% Increase (Decrease)			Nine Months Ended September 30,				% Increase (Decrease)
	2012		2011		2011 to 2012			2012		2011		2011 to 2012
	(in thousands)							(in thousands)
Revenues:
License revenue	$	76	$	76		—	%	$	229	$	229		—	%
Royalty revenue		279		914		(69)	%		2,353		2,863		(18)	%
Product sales		4,943		3,206		54	%		12,775		8,092		58	%
Product sales to related party		—		161		(100)	%		—		321		(100)	%
Total net revenues	$	5,298	$	4,357		22	%	$	15,357		11,505		33	%

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Revenues by geography are based on the billing address of the customer. The following table sets forth revenues by geographic area (in thousands):

	Three months ended				Nine months ended
	September 30,				September 30,
	2012		2011		2012		2011
United States	$	5,195	$	4,320	$	15,123	$	11,354
Europe		79		32		173		114
Rest of the world		24		5		61		37
	$	5,298	$	4,357	$	15,357	$	11,505

Revenues are generated from licensing fees, royalties earned, product sales, and contract arrangements. The accounting classification of product revenue as either royalties or product sales relates to the sales channels used by the Company, and as such, we believe that operating performance is most effectively evaluated by examining total net revenues.

The increase in net revenues of approximately $941,000 for the three months ended September 30, 2012 and $3.9 million for the nine months ended September 30, 2012 as compared to the same periods in 2011 reflects an increased volume demand for our PLAC Test ELISA Kit offset by a decline in average sales price for our product.

Our top four customers accounted for 71% and 70% of our net revenues for the three and nine months ended September 30, 2012, respectively, compared to 55% and 38%, respectively, for the same periods in 2011. Because of this customer concentration and the timing of orders from these customers, our quarterly revenue may fluctuate materially. Our largest customers are able to exert greater influence over our product pricing, which has led to a decline in average sales price in recent quarters. We expect moderate downward price pressure to continue for the remainder of the year. In 2013, we anticipate that the Company will be subject to a new medical device excise tax of 2.3% under the Patient Protection and Affordable Care Act of 2010. This new tax is anticipated to be imposed on our U.S. sales only. While our agreements with customers allow the Company to charge all applicable taxes, our customer concentration may adversely impact our ability to pass through and ultimately collect this new tax.

Product Costs

	Three Months Ended September 30,				% Increase (Decrease)			Nine Months Ended September 30,				% Increase (Decrease)
	2012		2011		2011 to 2012			2012		2011		2011 to 2012
	(in thousands)							(in thousands)
Product costs		1,558		1,439		8	%		4,875		3,776		29	%

Product costs include our expenditures for cost of goods, manufacturing support, product supplies, quality control, personnel expenses and facility costs. Product costs increased $119,000 for the three months ended September 30, 2012 compared to the three months ended September 30, 2011. This increase primarily reflects an increase in product-related materials and supplies costs of approximately $106,000 due to increased demand for our PLAC Tests, an increase in facilities related expense of $37,000 due to our relocation to a larger facility and an increase of approximately $23,000 in equipment depreciation costs used to produce our PLAC Test ELISA Kit. These cost increases were partially offset by a decrease of approximately $42,000 in severance cost.

Product costs increased $1.1 million for the nine months ended September 30, 2012 compared to the nine months ended September 30, 2011. This increase primarily reflects an increase in product-related materials and supplies costs of approximately $782,000 due to increased demand for our PLAC Tests, an increase in facilities related expenses of $249,000 due to our relocation to a larger facility and an increase of approximately $111,000 in maintenance and depreciation costs of equipment used to produce our PLAC Test ELISA Kit. These cost increases were partially offset by a decrease of approximately $42,000 in severance costs. We expect product costs to continue to increase due to volume demand growth for our PLAC Tests, partially offset by production economies of scale. We anticipate the new medical device excise tax will be included as a product cost in 2013.

Sales and Marketing Expenses

	Three Months Ended September 30,				% Increase (Decrease)			Nine Months Ended September 30,				% Increase (Decrease)
	2012		2011		2011 to 2012			2012		2011		2011 to 2012
	(in thousands)							(in thousands)
Sales and marketing expenses		1,297		1,207		7	%		3,929		3,291		19	%

Sales and marketing expenses include our expenditures on customer support, medical and other consultant fees, marketing programs and materials, and personnel expenses. Sales and marketing expenses increased $90,000 for the three months ended September 30, 2012 compared to the three months ended

19

September 30, 2011. This increase primarily reflects higher personnel expenses of approximately $287,000 due to expansion of our sales and marketing team, partially offset by a decrease in severance costs incurred in connection with the departure of our former Chief Commercial Officer of approximately $196,000.

Sales and marketing expenses increased $638,000 for the nine months ended September 30, 2012 compared to the nine months ended September 30, 2011. The increase primarily reflects an increase in personnel costs of approximately $630,000 due to an expansion of our sales and marketing team, an increase in travel expense of approximately $136,000 due to higher personnel expenses, travel costs related to a product launch in Europe, and an increase in marketing program expense of approximately $99,000. These cost increases were partially offset by a decrease in severance costs incurred in connection with the departure of our former Chief Commercial Officer of approximately $196,000 and a decrease in facility-related costs of approximately $34,000.

We expect our sales and marketing expenses to increase as we identify and hire additional personnel and as we develop and commercialize new products to maintain and expand our position in the market for diagnostics in cardiovascular disease.

Research and Development Expenses

	Three Months Ended September 30,				% Increase (Decrease)			Nine Months Ended September 30,				% Increase (Decrease)
	2012		2011		2011 to 2012			2012		2011		2011 to 2012
	(in thousands)							(in thousands)
Research and development expenses		912		1,449		(37	)%		3,297		4,215		(22	)%

Research and development expenses include costs related to product development, regulatory support of our technology and other technical support costs, including salaries and consultant fees. Research and development expenses decreased $537,000 for the three months ended September 30, 2012 compared to the three months ended September 30, 2011. This decrease primarily reflects a decrease in personnel and severance costs of approximately $409,000 due principally to the departure of our former Chief Science Officer in October 2011, a reduction in lab and facility costs associated with product development of approximately $72,000, a reduction in travel and entertainment expense of approximately $30,000 and a reduction of expenses related to clinical studies of approximately $13,000.

Research and development expenses decreased $918,000 for the nine months ended September 30, 2012 compared to the nine months ended September 30, 2011. This decrease primarily reflects a reduction in personnel and severance costs of approximately $787,000 due principally to the departure of our former Chief Science Officer in October 2011 and a decrease in travel and entertainment expense of approximately $14,000. These cost decreases were partially offset by an increase in lab and facility expense of approximately $119,000, due partly to our relocation to a larger facility.

We expect research and development costs will increase in the future reflecting staffing increases and new product development projects.

General and Administrative Expenses

	Three Months Ended September 30,				% Increase (Decrease)			Nine Months Ended September 30,				% Increase (Decrease)
	2012		2011		2011 to 2012			2012		2011		2011 to 2012
	(in thousands)							(in thousands)
General and administrative expenses		1,674		2,150		(22	)%		5,354		7,106		(25	)%

General and administrative expenses include personnel costs for finance, administration, information systems and professional fees as well as facilities expenses. General and administrative expenses decreased $476,000 for the three months ended September 30, 2012 compared to the three months ended September 30, 2011. This decrease primarily reflects a reduction in facility costs of approximately $497,000 for the 343 Oyster Point facility due to the expiration of the associated facility lease in January 2012, no repeat of prior period expenses related to our move to 349 Oyster Point of approximately $117,0000 and a reduction of consulting expense of approximately $15,000. These cost decreases were partially offset by reduced sublease income of approximately $151,000, due to the expiration of the 343 Oyster Point facility lease.

General and administrative expenses decreased $1.8 million for the nine months ended September 30, 2012 compared to the nine months ended September 30, 2011. This decrease primarily reflects a reduction in facility costs of approximately $1.8 million for the 343 Oyster Point facility due to the expiration of the associated facility lease in January 2012, a reduction in severance

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costs primarily associated with the resignation of the Company’s former Chief Executive Officer in June 2011 of approximately $861,000 and no repeat of prior period costs associated with our move to 349 Oyster Point of approximately $145,000. These cost decreases were partially offset by the loss of sublease income of $809,000, an increase in outside professional services costs of $141,000, and an increase in accrued compensation of $118,000.

We expect general and administrative expenses to stay relatively unchanged in the near future.

Interest Income, Interest Expense and Other Income (Expense), net

	Three Months Ended September 30,					% Increase (Decrease)			Nine Months Ended September 30,					% Increase (Decrease)
	2012			2011		2011 to 2012			2012			2011		2011 to 2012
	(in thousands)								(in thousands)
Interest income, interest expense and other income (expense), net
Interest income	$	3		$	12		(75	)%	$	14		$	44		(68	)%
Interest expense		(99	)		390		(125	)%		(302	)		390		(177	)%
Other income (expense), net		(1	)		9		(111	)%		(4	)		9		(144	)%
Total Interest and other income (expense)	$	(97	)	$	411		(124	)%	$	(292	)	$	443		(166	)%

Interest income is derived from cash balances, short-term and long-term investments. Interest expense is based on outstanding debt obligations. The increase in net interest and other expense was primarily due to a debt facility we entered into in September 2011. Interest expense will continue as long as the loan is outstanding and will trend down as the loan is repaid. Total interest and other income for the three and nine months ended September 30, 2011 reflect a reversal, in the third quarter of 2011, of $398,000 in tax-related accrued interest and penalties due to the expiration of the statute of limitations.

Income Taxes

	Three Months Ended September 30,				% Increase (Decrease)			Nine Months Ended September 30,						% Increase (Decrease)
	2012		2011		2011 to 2012			2012			2011			2011 to 2012
	(in thousands)							(in thousands)
Income tax provision		1		2		(50	)%		(2	)		(1	)		100	%

We generated net loss for the three and nine months ended September 30, 2012 and had no federal income tax provision. Our effective tax rate was 0% for income tax for the three and nine months ended September 30, 2012 and we expect that our effective tax rate for the full year 2012 will be 0%. In addition, we have substantial net operating loss carry forwards available to offset future taxable income for federal and state income tax purposes. At September 30, 2012, we had unrecognized tax benefits totaling $1.4 million. Our ability to utilize our net operating losses may be limited due to changes in our ownership as defined by Section 382 of the Code.

Under the provisions of Sections 382 and 383 of the Internal Revenue Code (the “Code”), a change of control, as defined in the Code, may impose an annual limitation on the amount of the Company’s net operating loss and tax credit carryforwards, and other tax attributes that can be used to reduce future tax liabilities. As a result of a merger transaction involving us in 2010, certain of the Company’s tax attributes prior to the merger transaction are subject to an annual limitation of $240,000 for federal and state purposes.

Liquidity and Capital Resources

Since our inception, we have incurred losses, and we have relied primarily on private placements of preferred stock and debt financing, as well as on revenue generated from the sale of products, to fund our operations. As of September 30, 2012, we had an accumulated deficit of $197.3 million, working capital of $14.8 million and stockholders’ equity of $9.1 million. Based on our current operating plan, we believe that our existing cash, cash equivalents, and investment securities will be sufficient to cover our cash needs for operating activities and commitments for at least twelve months.

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Cash, Cash Equivalents and Investments

As of September 30, 2012, we had cash, cash equivalents and short-term investments of $14.0 million, compared to $17.2 million at December 31, 2011. The decrease of $3.2 million primarily reflects cash used in operating activities of $3.1 million.

Cash Flows from Operating Activities

Net cash used in operating activities was $3.1 million for the nine months ended September 30, 2012, and was primarily related to the net loss of $2.4 million, adjusted for non-cash items of $0.4 million in depreciation and amortization, $0.3 million in stock-based compensation, $0.4 million in unfavorable lease amortization and $1.1 million cash outflow related to changes in operating assets and liabilities.

Net cash used in operating activities was $5.0 million for the nine months ended September 30, 2011, and was primarily related to net loss of $6.4 million, adjusted for non-cash items of $0.6 million in stock-based compensation, $0.4 million of depreciation and amortization, $0.4 million of tax provision adjustments, $0.3 million in unfavorable lease amortization, $0.2 million in amortization on investments and $0.8 million cash inflow related to changes in operating assets and liabilities.

Cash Flows from Investing Activities

Net cash provided by investing activities in the nine months ended September 30, 2012 was $5.6 million, primarily due to net investment maturities of $5.7 million and a restricted cash release of $0.4 million relating to the expiration of the 343 Oyster Point facility lease in January 2012. This cash provided by investing activities was partially offset by $0.6 million in purchases of property and equipment.

Net cash used in investing activities in the nine months ended September 30, 2011 was $10.2 million, primarily due to net purchases of available-for-sale investments of $10.0 million and $0.3 million in purchases of property and equipment.

Cash Flows from Financing Activities

Net cash provided by financing activities in the nine months ended September 30, 2012 was $18,000, reflecting proceeds from stock option exercises, partially offset by a fee paid relating to the amendment of a loan and security agreement first entered into in September 2011.

Net cash provided by financing activities in the nine months ended September 30, 2011 was $5.0 million, reflecting proceeds received upon the closing of a term loan associated with the loan and security agreement.

Other Information

Our future capital requirements will depend primarily upon our ability to maintain and grow our current product revenues, to develop and commercialize new products, to manage our obligations under real estate leases, to realize the sale of our assets held for sale, and to improve our reimbursement prospects from third-party payors, including:

• Our ability to obtain regulatory approval for the PLAC Test for Lp-PLA₂ Activity in the United States;

• The rate of product adoption by laboratories and doctors;

• Our ability to expand commercialization of the PLAC Test for Lp-PLA₂ Activity in Europe; and

• The third-party payor community’s acceptance of and reimbursement for the PLAC Tests.

We expect to require additional financing and will seek to raise funds through equity or debt offerings, bank facilities, or other sources of capital. Additional funding may not be available when needed or on terms acceptable to us. Any additional equity financing may be dilutive to stockholders, and debt financing, if available, may involve restrictive covenants. We cannot assure you that we will be able to raise any such additional funding.

We have incurred substantial losses since inception, and expect to continue to incur net losses for at least the next few years if we engage in new development activities to broaden or enhance our product pipeline. To date, we have funded our operations primarily through private placements of preferred stock and debt financing, as well as through revenue generated from the sale of products.

In September 2011, we entered into a loan and security agreement with Comerica Bank, which was amended in September of 2012 (see Note 9 of the Notes to Condensed Financial Statements included in this Quarterly Report on Form 10-Q). This loan contains various covenants.

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If we breach any of these covenants or are unable to make a required payment of principal or interest, or experience a material adverse change to our business, it could result in a default under the loan. Additionally, we are required to achieve revenues equal to at least 80% of monthly projections approved by our Board of Directors and provided to the bank, and failure to do so could result in a default under the loan. Upon the occurrence of an event of default under the loan, the bank could elect to declare all amounts outstanding to be immediately due and payable, which would increase our liquidity requirements beyond the currently expected levels. If we are unable to repay those amounts, the bank could proceed against the collateral granted to them to secure such indebtedness. We have pledged substantially all of our assets, other than our intellectual property, as collateral under the loan. We are in compliance with all the debt covenants as of September 30, 2012.

In order to meet future liquidity needs, we may become reliant on additional equity and/or debt financing.

Commitments and Contingencies

Our contractual obligations and future minimum lease payments that are non-cancelable at September 30, 2012 are disclosed in the following table (in thousands):

	Total		2012(1)		2013		2014		2015		2016
Debt obligations	$	5,863	$	66	$	574	$	1,466	$	1,400	$	2,357
Operating lease obligations		11,090		608		2,505		2,581		2,658		2,738
Total contractual commitments	$	16,953	$	674	$	3,079	$	4,047	$	4,058	$	5,095

(1) Remainder of year.

Off-Balance Sheet Arrangements

As of September 30, 2012, we did not have any off-balance sheet arrangements as defined in Item 303(a)(4)(ii) of SEC

Regulation S-K.

Recent Accounting Pronouncements

See Note 2 of our Notes to Condensed Financial Statements for recent accounting pronouncements, including the expected dates of adoption and estimated effects on our financial statements.

Item 3. Quantitative and Qualitative Disclosure About Market Risk

In the normal course of business, our financial position is routinely subject to a variety of risks, including market risk associated with interest rate movement. We regularly assess these risks and have established policies and business practices intended to protect against these and other exposures. As a result, we do not anticipate material potential losses in these areas.

As of September 30, 2012, we had cash, cash equivalents and short-term investments of $14.0 million, consisting of cash, cash equivalents and highly liquid short-term investments and certificates of deposit. The values of our short-term investments will likely decline by an immaterial amount if market interest rates increase and, therefore, we believe our exposure to interest rate changes is immaterial. Declines of interest rates over time will, however, reduce our interest income from short-term investments.

During the three and nine months ended September 30, 2012, there were no material changes to our market risk disclosures as set forth in Part II Item 7A. “Quantitative and Qualitative Disclosure About Market Risk” in our Annual Report on Form 10-K for the year ended December 31, 2011.

Item 4. Controls and Procedures

Evaluation of Disclosure Controls and Procedures

We have performed an evaluation under the supervision and with the participation of our management, including our principal executive and principal financial officers, of the effectiveness of our disclosure controls and procedures, as defined in Rule 13a-15(e) under the Securities Exchange Act of 1934, as amended (the “Exchange Act”). Based on that evaluation, our management, including our principal executive and principal financial officers, concluded that our disclosure controls and procedures were effective as of September 30, 2012 to provide reasonable assurance that information required to be disclosed by us in the reports filed or submitted by us under the Exchange Act is recorded, processed, summarized and reported within the time periods specified in the SEC’s rules and forms and that such information is accumulated and communicated to management, including our principal executive and principal financial officers, as appropriate to allow timely decisions regarding required disclosures.

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Changes in Internal Controls

There were no changes in our internal control over financial reporting during the quarter ended September 30, 2012 that have materially affected, or are reasonably likely to materially affect, our internal control over financial reporting.

Inherent Limitations on Effectiveness of Controls

Internal control over financial reporting may not prevent or detect all errors and all fraud. A control system, no matter how well conceived and operated, can provide only reasonable, not absolute, assurance that the objectives of the control system are met. Projections of any evaluation of effectiveness of internal control to future periods are subject to the risk that controls may become inadequate because of changes in conditions, or that the degree of compliance with the policies or procedures may deteriorate. Accordingly, our disclosure controls and procedures are designed to provide reasonable, not absolute, assurance that the objectives of our disclosure control system are met.

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PART II – OTHER INFORMATION

Item 1. Legal Proceedings

The Company is from time to time subject to various claims and legal actions during the ordinary course of business. The Company believes that there are currently no claims or legal actions that would reasonably be expected to have a material adverse effect on its results of operations or financial condition.

Item 1A. Risk Factors

Investing in our securities involves a very high degree of risk. You should carefully consider the risks described below and all of the other information in our filings under the Exchange Act before making any investment decisions regarding our common stock. The risks and uncertainties described below are not the only ones we face. Additional risks and uncertainties that we do not know or that we currently deem immaterial may also negatively affect our business, financial condition, operating results, and prospects. In that case, the market price of our common stock could decline, and you could lose all or part of your investment.

Risks Relating to Our Business Operations

We have withdrawn our 510(k) premarket notification for FDA clearance of our PLAC Test for Lp-PLA₂ Activity, and we may be unable to submit a subsequent 510(k) premarket notification or to obtain clearance with respect to such application.

On June 17, 2011, we submitted a premarket notification to the FDA seeking clearance under Section 510(k) of the FDCA to market our PLAC Test for Lp-PLA₂ Activity. This new assay measures the activity levels of the Lp-PLA₂ enzyme in the blood, while the PLAC Test currently marketed in the United States utilizes an ELISA method that measures the concentration of the enzyme. The PLAC Test for Lp-PLA₂ Activity is capable of running on automated, high throughput clinical chemistry analyzers unlike the current PLAC Test ELISA Kit. Future commercialization of an assay capable of running on automated, high throughput clinical chemistry analyzers may be important for the expansion of the PLAC Tests market and revenue growth. On October 24, 2011, we elected to withdraw this application following discussions with the FDA. We plan to develop a new submission. We are in the process of identifying completed clinical trials acceptable to the FDA from which blood samples of patient cohorts may be obtained and then tested to demonstrate the effectiveness of the PLAC Test for Lp-PLA₂ Activity.

There can be no guarantee that we will identify appropriate clinical trials, or that serum samples can be obtained from such trials to support retesting of PLAC Test for Lp-PLA₂ Activity. We cannot assure you that the results of any such clinical trials will support the proposed clinical claims. There can be no guarantee that the FDA will clear the subsequent 510(k) submission on a timely basis, or at all. We are unable to predict the timing of retesting, submission date or receipt of clearance for the PLAC Test for Lp-PLA₂ Activity, which may result in a loss of potential customers and would have an adverse effect on our financial condition and our ability to maintain or expand our business.

Our future success depends on our ability to retain our Chief Executive Officer and other key employees and to attract, retain and motivate qualified personnel.

We depend on the efforts and abilities of our Chief Executive Officer, along with other senior management, our research and development staff and a number of other key management, sales, support, technical and administrative services personnel. Competition for experienced, high-quality personnel exists, and we cannot assure you that we can continue to recruit and retain such personnel. Our failure to hire, train and retain qualified personnel would impair our ability to develop new products and manage our business effectively.

We are an early stage company and have engaged in only limited sales and marketing activities for our first products, the PLAC Tests.

Our products may never gain significant acceptance in the marketplace and therefore never generate substantial revenue or profits for the Company. As is the case with all novel biomarkers, we must establish a market for our PLAC Tests and build that market through physician education and awareness programs. Publication in peer review journals of results from outcome studies using our products will be an important consideration in the adoption by physicians and in the coverage by insurers of our products. Our ability to commercialize successfully the PLAC Tests and other diagnostic products will depend on many factors, including:

• whether healthcare providers believe our PLAC Tests and any other diagnostic tests that we successfully develop provide sufficient incremental clinical utility;

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• whether we are able to demonstrate that treatment of individuals based on their Lp-PLA₂ levels improves clinical outcomes in prospective clinical studies; and

• whether health insurers, government health programs and other third-party payors will cover and pay for our diagnostic tests and the amounts they will reimburse.

These factors may present obstacles to commercial acceptance of our products, and we may need to devote substantial time and money to surmount these obstacles, and the result might not be successful.

Our business is characterized by a high degree of customer concentration. Our top four customers accounted for 72% and 57% of our accounts receivable as of September 30, 2012 and 2011, respectively, and 70% and 38% of our revenue for the nine months ended September 30, 2012 and 2011, respectively. The loss of one or more of these customers or a decline in revenue from one or more of these customers could have a material adverse effect on our business, financial condition, and results of operations.

Sales to a limited number of customers account for a significant portion of our revenue and accounts receivable. Our dependence on and the identity of our key customers may vary from period to period as a result of competition among our customers, developments related to our products, and changes in individual customers’ purchases of our products. We may experience greater or lesser customer concentration in the future, depending on future commercial agreements and whether we are able to grow our revenue from the PLAC Test for Lp-PLA₂ Activity. However, it is likely that our revenue and profitability will continue to be dependent on a very limited number of customers, and we may experience an even higher degree of customer concentration in the future. The loss of, material reduction in sales volume to, or significant adverse change in our relationship with any of our key customers could have a material adverse effect on our revenue in any given period and may result in significant annual and quarterly revenue variations. Moreover, our largest customers are able to exert greater influence over our product pricing, which has led to a decline in average sales price in recent quarters. Such downward pressure on our pricing has the potential to continue. In addition, we may be unable to collect related accounts receivables when due, which could have a material adverse effect on our business.

We rely on two manufacturers to supply materials for our PLAC Test ELISA Kit. If these manufacturers are unable to supply our materials in a timely manner, or at all, we may be unable to meet demand, which would have a material adverse effect on our business.

Prior to June 2012, we depended on a sole source to manufacture our PLAC Test ELISA Kit. In June 2012, we qualified a second manufacturer for our PLAC Test ELISA Kit, and we intend to order regularly from both of these third-party manufacturers in the future. We rely on our third-party manufacturers to maintain their manufacturing facility in compliance with FDA and other federal, state and/or local regulations including health, safety and environmental standards. If they fail to maintain compliance with FDA or other critical regulations, they could be ordered to curtail operations, which would have a material adverse impact on our business. In addition, increases in the prices we pay our manufacturer, or lapses in quality, such as failure to meet our specifications or the requirements of the Quality System Regulations, or QSR, and other regulatory requirements, could materially adversely affect our business. Any manufacturing defect or error discovered after our products have been produced and distributed could result in significant consequences, including costly recall procedures and damage to our reputation. Our ability to replace the existing manufacturers may be difficult, because the number of potential manufacturers is limited.

We currently depend on certain key vendors and suppliers of materials, some of which are sole source or for whom an alternative could be difficult to replace in a timely manner, that are essential for the manufacture of our products. Any interruption in the supply of product, or the inability to obtain materials from alternate sources in a timely manner, could impair our ability to supply the PLAC Test ELISA Kit and to meet the demands of our customers, which would have a material adverse effect on our business.

We manufacture our PLAC Test for Lp-PLA₂ Activity on-site in South San Francisco, California and we could experience process, quality control and shipping problems due to the early stage of manufacturing.

We have developed manufacturing of the PLAC Test for Lp-PLA₂ Activity in house. We are dependent on the expertise of our personnel for this product. We could observe performance deviations that have not been apparent during development, including performance and stability of the PLAC Test for Lp-PLA₂ Activity. The discovery of such performance deviations or of any manufacturing problems may adversely affect our sales in Europe.

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If third-party payors do not reimburse our customers for the use of our clinical diagnostic products or if they reduce reimbursement levels, our ability to sell our products will be harmed.

We sell our products primarily through distributors and to laboratory customers, substantially all of which receive reimbursement for the health care services they provide to their patients from third-party payors, such as Medicare, Medicaid and other government programs, private insurance plans and managed care programs. Third-party payors are increasingly attempting to contain health care costs by limiting both coverage and the level of reimbursement for medical products and services. Accordingly, third-party payors are increasingly challenging the prices charged for diagnostic tests. Most of these third-party payors may deny coverage and reimbursement if they determine that a product was not medically necessary or not used in accordance with cost-effective treatment methods, or was used for an unapproved indication.

In the United States, third-party payors generally require billing codes on claims for reimbursement that describe the services provided. For laboratory services, the American Medical Association (“AMA”) establishes most of the billing codes using a data code set called Current Procedural Terminology, or CPT, codes. Each third-party payor generally develops payment amounts and coverage policies for their beneficiaries or members that ties to the CPT code established for the laboratory test and, therefore, coverage and reimbursement may differ by payor even if the same billing code is reported for claims filing purposes. For laboratory tests without a specific billing code, payors often review claims on a claim-by-claim basis and there are increased uncertainties as to coverage and eligibility for reimbursement. Currently, the tests performed by our assays are described by existing CPT codes, but we cannot guarantee that the CPT codes will not be revised or new CPT codes will not be established for our future assays. If our customers are not reimbursed for our products, they may reduce or discontinue purchases of our products, which would cause our revenues to decline. Lower-than-expected, or decreases in, reimbursement amounts for tests performed using our products may decrease amounts physicians and other practitioners are able to charge patients, which in turn may adversely affect the willingness of physicians and other practitioners to purchase our products at prices we target, or at all. If we are unable to sell our products at target prices, our revenue and gross margins will suffer and our business could be materially harmed.

Our business, in particular the growth of our business, is dependent on our ability to successfully develop and commercialize novel diagnostic products and services based on biomarkers. If we fail to develop and commercialize or enter into collaborations for new diagnostic products, we may be unable to execute our business plan.

Our long-term ability to generate product revenue will depend in part on our ability to develop additional formats or versions of the PLAC Tests and other new diagnostic products. If internal efforts do not generate sufficient product candidates, we will need to identify third parties that wish to collaborate with us to develop new products and applications. Our ability to enter into third-party relationships will depend in part on our ability to negotiate acceptable license and related agreements. Even if we are successful in establishing collaborative arrangements, they may never result in the successful development or commercialization of any product candidate or the generation of any sales or royalty revenues. In addition, rapid technological developments and innovations characterize the markets for our products and services. Our success will depend in large part on our ability to correctly identify emerging trends, enhance capabilities, and develop and manufacture new products quickly, in a cost-effective manner, and at competitive prices. The development of new and enhanced products is a complex and costly process. We may need to make substantial capital expenditures and incur significant research and development costs to develop and introduce such new products and enhancements. If we fail to timely develop and introduce competitive new products or additional formats of our existing products, our business could be materially adversely affected.

International expansion of our business exposes us to significant risks associated with doing business outside of the United States.

Our business strategy incorporates international expansion, including establishing and maintaining direct sales and physician outreach and education capabilities outside of the United States and expanding our relationship with distributors. Doing business internationally involves a number of risks, including:

• multiple, conflicting and changing laws and regulations such as tax laws, export and import restrictions, employment laws, regulatory requirements and other governmental approvals, permits and licenses;

• failure by us or our distributors to obtain and maintain regulatory approvals for the use of our tests in various countries;

• difficulties in managing foreign operations;

• complexities associated with managing multiple payor reimbursement regimes or patient self-pay systems;

• logistics and regulations associated with shipping, including infrastructure conditions and transportation delays;

• limits in our ability to penetrate international markets if we are not able to process tests locally;

• financial risks, such as longer payment cycles, difficulty collecting accounts receivable and exposure to foreign currency exchange rate fluctuations;

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• natural disasters, political and economic instability, including wars, terrorism, and political unrest, outbreak of disease, boycotts, curtailment of trade and other business restrictions; and

• regulatory and compliance risks that relate to maintaining accurate information and control over sales and distributors’ activities that may fall within purview of the Foreign Corrupt Practice Act, its books and records provisions or its anti-bribery provisions.

Any of these factors could significantly harm our future international expansion and operations and, consequently, our revenues and results of operations.

Our dependence on distributors for foreign sales of our PLAC Test for Lp-PLA₂ Activity could limit or prevent us from selling our test in Europe and from realizing long-term international revenue growth.

As of September 30, 2012, we had exclusive distribution agreements for our products in 15 European countries, and we may enter into other similar arrangements in other countries in the future. Exclusive distribution arrangements limit our ability to directly, or indirectly through other distributors to address customers in those countries. Distributors may not commit the necessary resources to market and sell our PLAC Tests to the level of our expectations. We intend to grow our business internationally, and to do so we may need to attract additional distributors to expand the territories in which we sell our PLAC Test for Lp-PLA₂ Activity. If current or future distributors do not perform adequately, or we are unable to locate distributors in particular geographic areas, we may not realize long-term international revenue growth.

The requirements of being a public company have required and will continue to require significant resources, increase our costs and occupy our management, and we may be unable to comply with these requirements in a timely or cost-effective manner.

As a company with public reporting responsibilities, we have incurred and will continue to incur significant legal, accounting, and other compliance expenses in meeting the requirements to:

• prepare and file and distribute periodic and current reports under the Exchange Act for a larger operating business and comply with other Exchange Act requirements applicable to public companies;

• formalize old and establish new internal policies, such as those relating to insider trading and disclosure controls and procedures;

• involve and retain to a greater degree outside counsel and accountants in the above activities; and

• establish and maintain an investor relations function, including the provision of certain information on our website.

Compliance with these rules and regulations will cause us to incur significant legal and financial compliance costs. In addition, we are required to implement and maintain effective internal control over financial reporting and disclosure. In particular, we must perform system and process evaluation and testing of our internal control over financial reporting to allow management to report on the effectiveness of our internal control over financial reporting. Our testing may reveal deficiencies in our internal control over financial reporting that are deemed to be material weaknesses. We have incurred and expect to continue to incur significant expense and devote substantial management effort toward ensuring compliance with these requirements. Moreover, if we are not able to comply with these requirements in a timely manner, or if we identify deficiencies in our internal control over financial reporting that are deemed to be material weaknesses, the market price of our common stock could decline and we could be subject to sanctions or investigations by the SEC or other regulatory authorities, which would entail expenditure of additional financial and management resources.

Natural disasters, including earthquakes, may damage our facilities.

Our corporate and manufacturing facilities are located in California. Our facilities in California are in close proximity to known earthquake fault zones. As a result, our corporate, research and manufacturing facilities are susceptible to damage from earthquakes and other natural disasters, such as fires, floods and similar events. Although we maintain general business insurance against fires and some general business interruptions, there can be no assurance that the scope or amount of coverage will be adequate in any particular case. Insurance specifically for earthquake risks is not available on commercially reasonable terms.

Failure in our information technology and storage systems could significantly disrupt the operation of our business.

Our ability to execute our business plan depends, in part, on the continued and uninterrupted performance of our information technology systems, or IT systems. IT systems are vulnerable to damage from a variety of sources, including telecommunications or network failures, malicious human acts and natural disasters. Moreover, despite network security and back-up measures, some of our servers are potentially vulnerable to physical or electronic break-ins, computer viruses and

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similar disruptive problems. Despite the precautionary measures we have taken to prevent unanticipated problems that could affect our IT systems, sustained or repeated system failures that interrupt our ability to generate and maintain data could adversely affect our ability to operate our business.

Risks Relating to Government Regulations

We are subject to extensive regulation by the FDA and other regulatory agencies and failure to comply with such regulation could have a material adverse effect on our business, financial condition, and results of operations.

Our business and our medical device products, including our PLAC Tests, are subject to extensive regulation by the FDA and other federal, state, and foreign regulatory agencies. These laws and regulations govern many aspects of our products and operations, and the products and operations of our suppliers and distributors, including premarket clearance and approval, design, development and manufacturing, labeling, packaging, safety and adverse event reporting, recalls, storage, advertising, promotion, sales and record keeping. Failure to comply with these laws and regulations could result in, among other things, warning letters, civil or criminal penalties, injunctions, delays in clearance or approval of our products, withdrawal of cleared products, recalls, and other operating restrictions, all of which could cause us to incur significant expenses.

Before we can market or sell a new product or a significant modification to an existing product in the United States, we must obtain either clearance under Section 510(k) of the FDCA, or approval of a pre-market approval application, or PMA, from the FDA, unless an exemption applies. In the 510(k) clearance process, the applicant must demonstrate to the FDA’s satisfaction that a proposed device is “substantially equivalent” to a device legally on the market, known as a “predicate” device, with respect to intended use, technology and safety and effectiveness, in order to obtain clearance from the FDA to market the proposed device. Clinical data is sometimes required to support substantial equivalence. The PMA pathway requires an applicant to demonstrate the safety and effectiveness of the device based, in part, on extensive data, including, but not limited to, technical, preclinical, clinical trial, manufacturing, and labeling data. The FDA can delay, limit, or deny clearance or approval of a device for many reasons, including:

• we may not be able to demonstrate to the FDA’s satisfaction that our products are substantially equivalent to lawful predicate device or safe and effective for their intended uses;

• the data from our pre-clinical studies and clinical trials may be insufficient to support clearance or approval, where required;

• the manufacturing process or facilities we use may not meet applicable requirements; and

• changes in FDA clearance or approval policies or the adoption of new regulations may require additional data.

Further, any modification we make to a 510(k)-cleared device that could significantly affect its safety or effectiveness, or that would constitute a major change in its intended use, design, or manufacture, would require us to seek a new 510(k) clearance or, possibly, approval of a PMA. The FDA requires every manufacturer to make this determination in the first instance, but the FDA may review any manufacturer’s decision. The FDA may not agree with our decisions regarding whether new clearances or approvals are necessary for changes to 510(k) cleared devices. If the FDA disagrees with our determination and requires us to submit new 510(k) notifications or PMAs for modifications to our previously cleared products for which we have concluded that new clearances or approvals are unnecessary, we may be required to cease marketing or to recall the modified product until we obtain clearance or approval, and we may be subject to significant regulatory fines or penalties.

Even when a product reaches the market, the subsequent discovery of previously unknown problems, such as material deficiencies or defects in design, labeling, or manufacture, or a potential unacceptable risk to health, with a product may result in restrictions on the product, including recall or withdrawal of the product from the market, and/or a requirement to submit a new 510(k) submission or PMA for the product in order to support continued marketing.

We and our suppliers are subject to inspections by the FDA and other regulatory agencies and deficiencies identified during these audits could have a material adverse effect on our results of operations.

Once regulatory clearance or approval has been granted, the product and its manufacturer are subject to continual review by the FDA and other regulatory authorities. For example, we are also subject to routine inspection by the FDA and certain state agencies for compliance with the QSR, which establishes the good manufacturing practices for medical devices, and Medical Device Reporting regulations, which require us to report to the FDA any incident in which one of our products may have caused or contributed to a death or serious injury or malfunctioned in a way that could cause death or serious injury. Although we believe that we have adequate processes in place to ensure compliance with these and other postmarket requirements, the FDA or other regulatory bodies could disagree and take enforcement action including issuing warning letters, untitled letters, fines, injunctions, consent decrees or civil penalties, or imposing operating restrictions or partial suspension or total shutdown of manufacturing, selling or exporting our products, among other sanctions, if it concludes that

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we are out of compliance with applicable regulations or if it concludes that our products pose an unacceptable risk to health or are otherwise deficient in design, labeling or manufacture. Further, the ability of our suppliers to supply critical components or materials and of our distributors to sell our products could be adversely affected if their operations are determined to be out of compliance. The FDA and other regulatory bodies could also require us to recall products if we fail to comply with applicable regulations. Such actions by the FDA and other regulatory bodies would adversely affect our revenues and results of operations.

We are and will be subject to new regulations which could have a material adverse effect on our results of operations.

Many national, regional, and local laws and regulations, including the recently-enacted healthcare reform legislation, have not been fully implemented by the regulatory authorities or adjudicated by the courts, and their provisions are open to a variety of interpretations. In the ordinary course of business, we must frequently make judgments with respect to compliance with applicable laws and regulations. If regulators subsequently disagree with the manner in which we have sought to comply with these regulations, we could be subjected to various sanctions, including substantial civil and criminal penalties, as well as product recall, seizure or injunction with respect to the sale of our products. Such sanctions could severely impair our reputation within the industry and any limitation on our ability to manufacture and market our products could have a material adverse effect on our business. In addition, in January 2011, the FDA announced twenty-five action items it intends to take in reforming the 510(k) premarket review program. The FDA issued its recommendations and proposed action items in response to concerns from both within and outside of the FDA about the 510(k) program. Although the FDA has not detailed the specific modifications or clarifications that the Agency intends to make to its guidance, policies, and regulations pertaining to the review and regulation of devices such as ours which seek and receive marketing clearance through the 510(k) process, the FDA’s announced action items signal that additional regulatory requirements are likely. For example, in July 2011, the FDA issued a draft guidance document intended to clarify when changes to a cleared 510(k) warrant submission of a new 510(k), which many observers believe will result in an increase in the number of 510(k)s submitted to the FDA. The FDA intends to issue a variety of additional draft guidance and regulations over the coming months and years which would, among other things, establish a Unique Device Identification System and clarify the FDA’s use and application of several key terms in the 510(k) review process. These reforms, when fully implemented, could impose additional regulatory requirements upon us which could delay our ability to obtain new clearances, increase the cost of compliance, or restrict our ability to maintain our current 510(k) clearances.

Healthcare reform and its restrictions on coverage and reimbursement may adversely affect our profitability.

Legislation both proposed and passed has had an impact on reimbursement levels for diagnostic services, including laboratory tests. For instance, in March 2010, President Barack Obama signed the Patient Protection and Affordable Care Act, as amended by the Health Care and Education Reconciliation Act (collectively, the “PPACA”), which makes a number of substantial changes to the way health care is financed by both governmental and private insurers. Among other things, the PPACA mandates a reduction in payments for clinical laboratory services paid under the Medicare Clinical Laboratory Fee Schedule of 1.75% for the years 2011 through 2015. A productivity adjustment also is made to the fee schedule payment amount. In addition, on February 22, 2012, President Obama signed the Middle Class Tax Relief and Job Creation Act of 2012, which, among other things, mandated an additional change in Medicare reimbursement for clinical laboratory services. This legislation requires a rebasing of the Medicare clinical laboratory fee schedule to effect a 2% reduction in payment rates otherwise determined for 2013, which in turn will serve as a base for 2014 and subsequent years. Further, with respect to the PPACA changes, the legislation establishes an Independent Payment Advisory Board (“IPAB”) to reduce the per capita rate of growth in Medicare spending. The IPAB has broad discretion to propose policies, which may have a negative impact on payment rates for services, including clinical laboratory services, beginning in 2016, and for hospital services beginning in 2020.

Although some of these provisions may negatively impact payment rates for clinical laboratory services, the PPACA also extends coverage to approximately 32 million previously uninsured people, which may result in an increase in the demand for our tests and services. There is significant uncertainty as to whether Congress will attempt to revise or terminate the PPACA, and there remain significant uncertainties regarding the measures that may be adopted as the PPACA is implemented.

In addition, other legislative changes have been proposed and adopted since the PPACA was enacted. Most recently, on August 2, 2011, President Obama signed into law the Budget Control Act of 2011, which, among other things, creates the Joint Select Committee on Deficit Reduction to recommend proposals in spending reductions to Congress. The Joint Select Committee did not achieve a targeted deficit reduction of at least $1.2 trillion for the years 2013 through 2021, triggering the legislation’s automatic reduction to several government programs. This includes aggregate reductions to Medicare payments to providers of up to 2% per fiscal year, starting in 2013. The full impact on our business of the PPACA and the new law is uncertain. Levels of reimbursement may decrease in the future, and future legislation, regulation or reimbursement policies of third-party payors may adversely affect the demand for and price levels of our products.

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We are subject to healthcare laws, regulation and enforcement, and our failure to comply with those laws could have a material adverse effect on our results of operations and financial conditions.

We are also subject to healthcare fraud and abuse regulation and enforcement by both the federal government and the states in which we conduct our business. The laws that may affect our ability to operate include:

• the federal Health Insurance Portability and Accountability Act of 1996 as amended by the Health Information Technology for Economic and Clinical Health Act, which governs the conduct of certain electronic healthcare transactions and protects the security and privacy of protected health information;

• the federal healthcare programs’ Anti-Kickback Statute, which prohibits, among other things, persons from knowingly and willfully soliciting, receiving, offering or paying remuneration, directly or indirectly, in exchange for or to induce either the referral of an individual for, or the purchase, order or recommendation of, any good or service for which payment may be made under federal healthcare programs such as the Medicare and Medicaid programs;

• federal false claims laws which prohibit, among other things, individuals or entities from knowingly presenting, or causing to be presented, claims for payment from Medicare, Medicaid, or other third-party payors that are false or fraudulent;

• federal criminal laws that prohibit executing a scheme to defraud any healthcare benefit program or making false statements relating to healthcare matters; and

• state law equivalents of each of the above federal laws, such as anti-kickback and false claims laws which may apply to items or services reimbursed by any third-party payor, including commercial insurers. If our operations are found to be in violation of any of the laws described above or any other governmental regulations that apply to us, we may be subject to penalties, including civil and criminal penalties, damages, fines, the curtailment or restructuring of our operations, the exclusion from participation in federal and state healthcare programs and imprisonment, any of which could adversely affect our ability to operate our business and our financial results.

Risks Relating to Liquidity

Our Comerica Bank loan contains restrictions that limit our flexibility in operating our business, and our lender may accelerate repayment of amounts outstanding under certain circumstances.

In September 2011, we entered into a loan and security agreement with Comerica Bank. This agreement was amended effective September 2012. This loan contains various covenants that limit our ability to engage in specified types of transactions. These covenants limit our ability to, among other things:

• Sell, transfer, lease or dispose of our assets;

• Create, incur or assume additional indebtedness;

• Encumber or permit liens on certain of our assets;

• Pay dividends on, repurchase or make distributions with respect to our common stock;

• Make specified investments;

• Consolidate, merge, sell or otherwise dispose of all or substantially all of our assets; and

• Enter into certain transactions with our affiliates.

If we breach of any of these covenants, are unable to make a required payment of principal or interest, or experience a material adverse change to our business, it could result in a default under the loan. Additionally, we are required to achieve revenues equal to at least 80% of monthly projections approved by our Board of Directors and provided to the bank, and our failure to do so could result in a default under the loan. Upon the occurrence of an event of default under the loan, the bank could elect to declare all amounts outstanding to be immediately due and payable. If we were unable to repay those amounts, the bank could proceed against the collateral granted to them to secure such indebtedness. We have pledged substantially all of our assets, other than our intellectual property, as collateral under the loan.

We will need to raise additional capital to support our operations in the future.

We will require additional funds to commercialize our products and develop new products. Our ability to fund our net losses and to conduct the required development activities related to any new product candidates will be significantly limited if we are unable to obtain the necessary capital. We will seek to raise funds through equity or debt offerings, bank facilities, or

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other sources of capital. Additional funding may not be available when needed or on terms acceptable to us. Any additional equity financing may be dilutive to stockholders, and debt financing, if available, may involve restrictive covenants. We cannot assure you that we will be able to raise any such additional funding.

We are an early stage company with a history of losses, we expect to incur losses for at least the next few years, and we may never achieve profitability.

We have incurred substantial net losses since our inception. Our accumulated deficit was $197.3 million at September 30, 2012. For the nine months ended September 30, 2012 and 2011, we incurred a net loss of $2.4 million and $6.4 million, respectively. We expect to continue to incur net losses for at least the next few years. If we are unable to execute our commercialization strategy to achieve profitability, or if the time required to achieve profitability is longer than we anticipate, we may not be able to continue our business.

We are solely dependent on our product line of PLAC Tests. We expect that the PLAC Tests will account for a substantial portion of our revenue for the foreseeable future. We do not know if our PLAC Tests will be successful over the long-term and it is possible that the demand for the product may decline over time. Any decline in demand or failure of our PLAC Tests to penetrate current or new market significantly could have a material adverse effect on our business, financial condition, and results of operations.

We have liabilities for real estate leases in excess of what is necessary for our current business. We will incur these additional expenses until we are able to sublease a portion of our larger leased facility.

We have a significant real estate lease for a facility of approximately 65,000 square feet with current monthly minimum required expenses of approximately $220,000. The term of the lease continues until December 31, 2016. Until such time that we are able to sublease a portion of the facility, we will incur liabilities for real estate leases significantly in excess of what is necessary for our current business. We may never be able to sublease a portion of the facility.

Risks Relating to Intellectual Property

If the combination of patents, trade secrets, trademarks, and contractual provisions that we rely on to protect our intellectual property proves inadequate, our ability to successfully commercialize our products will be harmed and we may never be able to operate our business profitably.

Our success depends, in large part, on our ability to protect proprietary discoveries, technology, and diagnostic tests that we develop under the patent and other intellectual property laws of the United States and other countries, so that we can seek to prevent others from unlawfully using our inventions and proprietary information.

Additionally, we have filed or have license rights to a number of patent applications that are in an early stage of prosecution, and we cannot make any assurances that any of the pending patent applications will result in patents being issued. In addition, due to technological changes that may affect our proposed products or judicial interpretation of the scope of our patents, our proposed products might not, now or in the future, be adequately covered by our patents.

Moreover, the U.S. Leahy-Smith America Invents Act, enacted in September 2011, brings significant changes to the U.S. patent system, which include a change to a “first to file” system from a “first to invent” system and changes to the procedures for challenging issued patents and disputing patent applications during the examination process, among other things. The effects of these changes on our patent portfolio and business have yet to be determined, as the U.S. Patent and Trademark Office must still implement regulations relating to these changes and U.S. courts have yet to address the new provisions, but in any event, these changes could increase the costs and uncertainties surrounding the prosecution of our patent applications and the enforcement or defense of our patent rights.

Furthermore, there have been several cases involving patents claiming genetic materials and information, and diagnostic products and methods based on genetic materials and information, that are pending in U.S. courts or have been decided by the U.S. Supreme Court that may impact our business. On March 20, 2012, in Mayo Collaborative Services, DBA Mayo Medical Laboratories,

et al. v. Prometheus Laboratories, Inc., the U.S. Supreme Court issued an opinion holding that the processes claimed by Prometheus’ patent were not patent eligible because these processes—determining the relationships between concentrations of certain metabolites in the blood and the likelihood that a thiopurine drug dosage will prove ineffective or cause harm—merely apply laws of nature and are not themselves patentable. Additionally, a suit brought by multiple plaintiffs, including the American Civil Liberties Union, or ACLU, against Myriad Genetics and the USPTO, could also impact biotechnology patents. The Federal Circuit issued a written decision on July 29, 2011 that reversed the U.S. District Court for the Southern District of New York’s ruling that Myriad’s composition claims to “isolated” DNA molecules cover unpatentable subject matter. However, the Federal Court affirmed the District Court’s decision that Myriad’s method

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claims directed to simply “comparing” or “analyzing” DNA sequences without a “transformation” step are not patentable. The U.S. Supreme Court granted certiorari in the Myriad case, vacated the Federal Circuit decision and remanded the case back to the Federal Circuit for further consideration of patentability in light of the Supreme Court’s decision in Mayo v. Prometheus. Upon remand the Court of Appeals for the Federal Circuit issued a written decision on August 16, 2012 maintaining that Myriad’s composition claims to “isolated” DNA molecules cover patentable subject matter and that Myriad’s method claims directed to “comparing” or “analyzing” DNA sequences without a “transformation” step are not patentable. It is unknown if this decision will be appealed and whether or how pending cases will be decided. It is also unknown what impact, if any, the decisions in Prometheus and Myriad or decisions in pending cases will have on gene patents or diagnostic method patents generally or our ability to obtain or enforce such patents in the future.

We license key intellectual property from GlaxoSmithKline and ICOS, and our contractual relationships have certain limitations.

We have an exclusive license from GlaxoSmithKline and a co-exclusive license from ICOS Corporation (“ICOS”) to practice and commercialize technology covered by several issued and pending United States patents and their foreign counterparts. The issued patents that relate to the Company’s current business have expiration dates ranging from 2013 to 2016.

Several of our collaboration agreements with GlaxoSmithKline and ICOS provide licenses to use intellectual property that is important to our business, and we may enter into additional agreements in the future with GlaxoSmithKline or with other third parties that change licenses of valuable technology. Current licenses impose, and future licenses may impose, various commercialization, milestone and other obligations on us, including the obligation to terminate our use of patented subject matter under certain circumstances. If a licensor becomes entitled to, and exercises, termination rights under a license, we could lose valuable rights and our ability to develop our current and future products. Our business may suffer if any current or future licenses terminate, if the licensors fail to abide by the terms of the license or fail to prevent infringement by third parties, if the licensed patents or other rights are found to be invalid or if we are unable to enter into necessary licenses on acceptable terms.

Any inability to adequately protect our proprietary technologies and product candidates could harm our competitive position.

We will be able to protect our proprietary rights from unauthorized use by third parties only to the extent that our proprietary technologies are covered by valid and enforceable patents or are effectively maintained as trade secrets. We plan to continue to apply for patents covering our technologies and products as we deem appropriate. We cannot make assurances that our pending patent applications will issue as patents and, if they do, whether the scope of such claims will be sufficiently broad to prevent third parties from utilizing our technologies, commercializing our discoveries or developing competing products. Any patents we currently hold, or obtain in the future, may not be sufficiently broad to prevent others from utilizing our technologies, commercializing our discoveries, or developing competing technologies and products. Furthermore, third parties may independently develop similar or alternative technologies or design around our patented technologies. Third parties may challenge or invalidate our patents, or our patents may fail to provide us with any competitive advantage.

We have rights to patents and patent applications owned by GlaxoSmithKline, Human Genome Sciences, Inc. (“Human Genome Sciences”) and ICOS that provide important protection on the composition of matter and utility of our products and product candidates. We do not, however, directly control the prosecution and maintenance of all of these patents. GlaxoSmithKline, Human Genome Sciences, and ICOS may not fulfill their obligations as licensors and may allow these patents to go abandoned or may not pursue meaningful claims for our products. Also, while the United States Patent and Trademark Office has issued diagnostic patents covering utility or methods, we do not know whether or how courts will enforce these patents. If a court finds these types of inventions to be unpatentable or interprets them narrowly, the benefits of our patent strategy may not materialize. If any or all of these events occur, they could diminish the value of our intellectual property.

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Risks Relating to Our Stock

Our stock price is likely to be volatile.

Currently, our common stock is quoted on the OTC Bulletin Board. Stocks traded “over the counter” typically are subject to greater volatility than stocks traded on stock exchanges, such as the NASDAQ Stock Market, due to the fact that OTC trading volumes are generally significantly lower than those on stock exchanges. This lower volume may allow a relatively few number of stock trades to greatly affect the stock price, particularly where the trading price of the stock price is relatively low. The trading price of our common stock has been and is likely to continue to be extremely volatile. Some of the many factors that may cause the market price of our common stock to fluctuate include, in no particular order:

• Actions taken by regulatory authorities with respect to our products;

• The progress and results of our product development efforts;

• The outcome of legal actions to which we may become a party;

• Our ability to commercialize the products, if any, that we are able to develop;

• Changes in our capital structure, such as future issuances of securities or the incurrence of additional debt; and

• Restatements of our financial results and/or material weaknesses in our internal controls.

The stock markets and the markets for medical diagnostics and biotechnology stocks in particular, have experienced volatility that has often been unrelated to the operating performance of particular companies. These broad market fluctuations may adversely affect the trading price of our common stock. Investors may not be able to sell when they desire due to insufficient buyer demand and may realize less than, or lose all of, their investment.

We are not currently listed on a national exchange and there can be no assurance we will ever be listed.

As a result of our failure to make timely filings of financial statements, we were delisted from The NASDAQ Stock Market in 2004. Currently, our common stock is quoted on the OTC Bulletin Board under the symbol DDXS. We have not yet applied for our common stock to be listed on a national exchange, and we do not currently meet all of the requirements for listing or relisting on the NASDAQ Stock Market. We do not know when, if ever, our common stock will be listed on a national stock exchange. In addition, we cannot be certain that The NASDAQ Stock Market will approve our stock for relisting or that any other exchange will approve our stock for listing. In order to be eligible for relisting or listing, we must meet the initial listing criteria for The NASDAQ Stock Market or another national exchange, including a minimum per share price.

Our charter documents and Delaware law may discourage an acquisition of the Company.

Provisions of our certificate of incorporation, bylaws, and Delaware law could make it more difficult for a third-party to acquire us, even if doing so would be beneficial to our stockholders. We may issue shares of preferred stock in the future without stockholder approval and upon such terms as our Board of Directors may determine. Our issuance of this preferred stock could have the effect of making it more difficult for a third-party to acquire, or of discouraging a third-party from acquiring, a majority of our outstanding stock. Our bylaws also provide that special stockholders meetings may be called only by our Board of Directors, Chairperson of the Board of Directors, or by our Chief Executive Officer or President, with the result that any third-party takeover not supported by the Board of Directors could be subject to significant delays and difficulties.

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

On September 11, 2012, the Company issued a warrant to Comerica Bank exercisable for 168,919 shares of the Company’s common stock at an exercise price of $0.37 per share. The warrant is exercisable until September 11, 2019. The warrant was issued as partial consideration for Comerica Bank providing the Company with a loan amendment, as described in more detail under the heading “Notes Payable” in Note 9 – “Notes Payable” and Note 13 – “Stock Warrants”, of the Notes to Condensed Financial Statements included in this Quarterly Report on Form 10-Q. The warrant was issued in reliance on the exemption from registration provided by Section 4(2) of the Securities Act of 1933, as amended, for transactions not involving a public offering.”

Item 3. Defaults Upon Senior Securities.

None

Item 4. Mine Safety Disclosures.

Not applicable

Item 5. Other Information.

None

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Item 6. Exhibits

Exhibit No.	Description
3.1	Restated Certificate of Incorporation of the Registrant (incorporated by reference to Exhibit 3.1 to the Registrant’s Quarterly Report on Form 10-Q (file no. 0-26483) for the fiscal quarter ended September 30, 2010, filed on November 15, 2010)
3.2	Certificate of Change of Registered Agent and Registered Office (incorporated by reference to Exhibit 3.1 to the Registrant’s Current Report on Form 8-K (file no. 0-26483), filed on January 25, 2011)
3.3	Amendment to Restated Certificate of Incorporation of the Registrant (incorporated by reference to Exhibit 3.1 to the Registrant’s Current Report on Form 8-K (file no. 0-26483), filed on July 18, 2011)
3.4	Amended and Restated Bylaws of the Registrant (incorporated by reference to Exhibit 3.2 to the Registrant’s Current Report on Form 8-K (file no. 0-26483), filed on November 5, 2010)
4.1	Warrant to purchase shares of Common Stock, issued to Comerica Bank on September 11, 2012
10.1*	Purchase Agreement with Atherotech Diagnostics Lab, dated August 23, 2012 and effective as of August 20, 2012.
10.2*	Volume Discount Program Addendum with Atherotech Diagnostics Lab, dated August 23, 2012 and effective as of August 20, 2012.
10.3*	Amended and Restated Loan and Security Agreement by and between diaDexus, Inc. and Comerica Bank, dated September 11, 2012.
31.1	Certification of Chief Executive Officer pursuant to Exchange Act Rule 13a-14(a)
31.2	Certification of Chief Financial Officer pursuant to Exchange Act Rule 13a-14(a)
32.1	Certification of Chief Executive Officer pursuant to 18 U.S.C. Section 1350, as adopted pursuant to Section 906 of the Sarbanes-Oxley Act of 2002
32.2	Certification of Chief Financial Officer pursuant to 18 U.S.C. Section 1350, as adopted pursuant to Section 906 of the Sarbanes-Oxley Act of 2002
101.INS**	XBRL Instance Document
101.SCH**	XBRL Taxonomy Extension Schema Document
101.CAL**	XBRL Taxonomy Extension Calculation Linkbase Document
101.LAB**	XBRL Taxonomy Extension Label Linkbase Document
101.PRE**	XBRL Taxonomy Extension Presentation Linkbase Document

* Certain portions have been omitted pursuant to a confidential treatment request. Omitted information has been filed separately with the SEC.

** Pursuant to Rule 406T of Regulation S-T, these interactive data files are deemed not filed or part of a registration statement or prospectus for purposes of Sections 11 or 12 of the Securities Act of 1933, as amended, or Section 18 of the Securities Exchange Act of 1934, as amended, and otherwise are not subject to liability under those sections.

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SIGNATURES

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

	diaDexus, Inc.
Date: November 7, 2012	By:	/s/ Brian E. Ward
		Brian E. Ward
		President & Chief Executive Officer
Date: November 7, 2012	By:	/s/ Jean-Frédéric Viret
		Jean-Frédéric Viret
		Chief Financial Officer

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EXHIBIT INDEX

Exhibit No.	Description
3.1	Restated Certificate of Incorporation of the Registrant (incorporated by reference to Exhibit 3.1 to the Registrant’s Quarterly Report on Form 10-Q (file no. 0-26483) for the fiscal quarter ended September 30, 2010, filed on November 15, 2010)
3.2	Certificate of Change of Registered Agent and Registered Office (incorporated by reference to Exhibit 3.1 to the Registrant’s Current Report on Form 8-K (file no. 0-26483), filed on January 25, 2011)
3.3	Amendment to Restated Certificate of Incorporation of the Registrant (incorporated by reference to Exhibit 3.1 to the Registrant’s Current Report on Form 8-K (file no. 0-26483), filed on July 18, 2011)
3.4	Amended and Restated Bylaws of the Registrant (incorporated by reference to Exhibit 3.2 to the Registrant’s Current Report on Form 8-K (file no. 0-26483), filed on November 5, 2010)
4.1	Warrant to purchase shares of Common Stock, issued to Comerica Bank on September 11, 2012
10.1*	Purchase Agreement with Atherotech Diagnostics Lab, dated August 23, 2012 and effective as of August 20, 2012.
10.2*	Volume Discount Program Addendum with Atherotech Diagnostics Lab, dated August 23, 2012 and effective as of August 20, 2012.
10.3*	Amended and Restated Loan and Security Agreement by and between diaDexus, Inc. and Comerica Bank, dated September 11, 2012.
31.1	Certification of Chief Executive Officer pursuant to Exchange Act Rule 13a-14(a)
31.2	Certification of Chief Financial Officer pursuant to Exchange Act Rule 13a-14(a)
32.1	Certification of Chief Executive Officer pursuant to 18 U.S.C. Section 1350, as adopted pursuant to Section 906 of the Sarbanes-Oxley Act of 2002
32.2	Certification of Chief Financial Officer pursuant to 18 U.S.C. Section 1350, as adopted pursuant to Section 906 of the Sarbanes-Oxley Act of 2002
101.INS**	XBRL Instance Document
101.SCH**	XBRL Taxonomy Extension Schema Document
101.CAL**	XBRL Taxonomy Extension Calculation Linkbase Document
101.LAB**	XBRL Taxonomy Extension Label Linkbase Document
101.PRE**	XBRL Taxonomy Extension Presentation Linkbase Document

* Certain portions have been omitted pursuant to a confidential treatment request. Omitted information has been filed separately with the SEC.

** Pursuant to Rule 406T of Regulation S-T, these interactive data files are deemed not filed or part of a registration statement or prospectus for purposes of Sections 11 or 12 of the Securities Act of 1933, as amended, or Section 18 of the Securities Exchange Act of 1934, as amended, and otherwise are not subject to liability under those sections.

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