
	Nine Months Ended September 30, 2023
	Balance at Beginning of Period		Additions		Deductions		Balance at End of Period
Contract assets:
Accounts receivable(1)	$	1,901	$	1,426	$	(2,847)	$	480
Prepaid expenses and other current assets	$	781	$	—	$	(781)	$	—
Contract liability:
Deferred revenue	$	47,034	$	—	$	(3,738)	$	43,296

	Nine Months Ended September 30, 2022
	Balance at Beginning of Period		Additions		Deductions		Balance at End of Period
Contract assets:
Accounts receivable(1)	$	19,094	$	92,612	$	(109,836)	$	1,870
Prepaid expenses and other current assets	$	4,309	$	9,550	$	(8,250)	$	5,609
Contract liabilities:
Deferred revenue	$	42,380	$	66,307	$	(64,126)	$	44,561
Accounts payable	$	3,171	$	—	$	(3,171)	$	—

On December 11, 2015, the Company and MTPC entered into the MTPC Agreement, providing MTPC with exclusive development and commercialization rights to vadadustat in Japan and certain other Asian countries, collectively, the MTPC Territory, which was amended effective as of December 2, 2022. In addition, the Company supplies vadadustat to MTPC for both clinical and commercial use in the MTPC Territory. In February 2021, the Company entered into the Royalty Agreement with HCR, whereby the Company sold its right to receive royalties and sales milestones under the MTPC Agreement, subject to certain caps and other terms and conditions. See Note 5 for additional information and Note 5 of the Notes to the Consolidated Financial Statements in the 2022 Annual Report on Form 10-K/A for a more detailed description of the MTPC Agreement.

The Company identified two performance obligations in connection with its material promises under the MTPC Agreement as follows: (i) License, Research and Clinical Supply Performance Obligation and (ii) Rights to Future Know-How Performance Obligation. The Company allocates the transaction price to each performance obligation based on the Company’s best estimate of the relative standalone selling price. The Company developed a best estimate of the standalone selling price for the Rights to Future Know-How Performance Obligation primarily based on the likelihood that additional intellectual property covered by the license conveyed will be developed during the term of the arrangement and determined it is immaterial. As such, the Company did not develop a best estimate of standalone selling price for the License, Research and Clinical Supply Performance Obligation and allocated the entire transaction price to this performance obligation. The deliverables associated with the License, Research and Clinical Supply Performance Obligation were satisfied as of June 30, 2018.

The transaction price was comprised of: (i) the up-front payment of $20.0 million, (ii) the cost for the Phase 2 studies of $20.5 million, (iii) the cost of all clinical supply provided to MTPC for the Phase 3 studies, (iv) $10.0 million in development milestones received, (v) $25.0 million in regulatory milestones received, comprised of $10.0 million relating to the NDA filing

in Japan and $15.0 million relating to regulatory approval of vadadustat in Japan, and (vi) $4.4 million in royalties from net sales of Vafseo. As of September 30, 2023, all development milestones and $25.0 million in regulatory milestones have been achieved. No other regulatory milestones have been assessed as probable of being achieved and as a result have been fully constrained. The Company re-evaluates the transaction price in each reporting period and as uncertain events are resolved or other changes in circumstances occur. Revenue for the License, Research and Clinical Supply Performance Obligation for the MTPC Agreement is being recognized using a proportional performance method, for which all deliverables have been completed. During the three and nine months ended September 30, 2023, the Company recognized revenue from MTPC royalties totaling approximately $0.5 million and $1.4 million, respectively, and approximately $0.4 million and $1.2 million during the three and nine months ended September 30, 2022, respectively. As noted above, in February 2021, the Company entered into the Royalty Agreement, whereby the Company sold its right to receive these royalties and sales milestones under the MTPC Agreement, subject to certain caps and other terms and conditions (see Note 5 for additional information). The revenue is classified as license, collaboration and other revenue in the accompanying unaudited condensed consolidated statements of operations and comprehensive loss. As of September 30, 2023, there were no accounts receivable, contract assets, payables or deferred revenue recorded in connection with the MTPC Agreement.

On July 15, 2020, the Company and MTPC entered into a supply agreement, or MTPC Supply Agreement, under which the Company supplies vadadustat drug product to MTPC for commercial use in Japan and certain other Asian countries, as contemplated by the MTPC Agreement. See Note 5 of the Notes to the Consolidated Financial Statements in the 2022 Annual Report on Form 10-K/A for a more detailed description of this supply agreement.

On December 16, 2022, the Company, MTPC and Esteve Química, S.A., or Esteve, executed an Assignment of Supply Agreement, or Esteve Assignment Agreement, pursuant to which the Supply Agreement between the Company and Esteve, or Esteve Agreement (see Note 12) was assigned to MTPC. The Esteve Assignment Agreement transferred the rights and obligations of the Company under the Esteve Agreement to MTPC, including the obligations under certain purchase orders issued by the Company and accepted by Esteve that will continue to have a binding effect on MTPC to take delivery of the product from Esteve in accordance with the terms of the Esteve Agreement. The Company has no further obligation to take delivery of, or pay for, product delivered by Esteve.

The Company recognized no revenue and $3.7 million in revenue under the MTPC Supply Agreement during the three and nine months ended September 30, 2023, respectively, and $5.1 million and $12.7 million in revenue during the three and nine months ended September 30, 2022, respectively. Due to the Esteve Agreement, the Company no longer records accounts receivable, deferred revenue or other current liabilities relating to the MTPC Supply Agreement.

On June 4, 2021, the Company entered into a License Agreement, or Cyclerion Agreement, with Cyclerion Therapeutics Inc., or Cyclerion, pursuant to which Cyclerion granted the Company an exclusive global license under certain intellectual property rights to research, develop and commercialize praliciguat, an investigational oral soluble guanylate stimulator.

Under the terms of the Cyclerion Agreement, the Company made an upfront payment of $3.0 million in cash to Cyclerion, which was paid and recorded to research and development expense in June 2021. Substantially all of the fair value of the assets acquired in conjunction with the Cyclerion Agreement was concentrated in the acquired license. As a result, the Company accounted for this transaction as an asset acquisition under ASU No. 2017-01, Business Combinations (Topic 805): Clarifying the Definition of a Business. The upfront payment was charged to expense at acquisition, as it relates to a development stage compound with no alternative future use. In addition, Cyclerion is eligible to receive up to an aggregate of $222.0 million from the Company in specified development and regulatory milestone payments on a product-by-product basis. Cyclerion will also be eligible to receive specified commercial milestones as well as tiered royalties ranging from a low-single-digit- to mid-double-digit percentage of net sales, on a product-by-product basis, and subject to reduction upon expiration of patent rights or the launch of a generic product in the territory. A more detailed description of this agreement can be found in Note 5 of the Notes to the Consolidated Financial Statements in the 2022 Annual Report on Form 10-K/A.

On May 12, 2017, the Company entered into a License Agreement, as amended and restated on February 18, 2022, or the Vifor Agreement, with Vifor (International) Ltd. (now a part of CSL Limited), or CSL Vifor, which grants CSL Vifor an exclusive license to sell vadadustat to Fresenius Kidney Care Group LLC, an affiliate of Fresenius Medical Care North America, or FMCNA, and its affiliates, including Fresenius Kidney Care Group LLC, to certain third-party dialysis organizations approved by the Company, to independent dialysis organizations that are members of certain group purchasing organizations and certain non-retail specialty pharmacies, collectively, the Supply Group, in the United States, or Vifor Territory. CSL Vifor has agreed not to sell or otherwise supply vadadustat until the FDA has granted regulatory approval for vadadustat for the treatment of

The Vifor Agreement is structured as a profit share arrangement between the Company and CSL Vifor in which the Company will receive approximately 66% of the profits, net of certain pre-specified costs. In addition, CSL Vifor made an upfront payment to the Company of $25.0 million in February 2022 in connection with the amendment and restatement of the Vifor Agreement, which was recorded as long-term deferred revenue in the accompanying unaudited condensed consolidated balance sheet.

Unless earlier terminated, the Vifor Agreement will expire upon the later of the expiration of all patents that claim or cover vadadustat or expiration of marketing or regulatory exclusivity for vadadustat in the Vifor Territory. CSL Vifor may terminate the Vifor Agreement in its entirety upon 30 months' prior written notice after the first anniversary of the receipt of regulatory approval, if approved from the FDA for vadadustat for dialysis-dependent CKD patients. The Company may terminate the Vifor Agreement in its entirety for convenience, following the earlier of a certain period of time elapsing or following certain specified regulatory events and upon six months’ prior written notice. If the Company so terminates for convenience, subject to specified exceptions, the Company will pay a termination fee to CSL Vifor. In addition, either party may, subject to a cure period, terminate the Vifor Agreement in the event of the other party’s uncured material breach or bankruptcy.

On February 18, 2022, in connection with the amendment and restatement, the Company and CSL Vifor entered into an investment agreement, or Second Investment Agreement, pursuant to which the Company sold an aggregate of 4,000,000 shares of its common stock, or 2022 Shares, to CSL Vifor at a price per share of $5.00 for a total of $20 million on February 22, 2022.

The amounts representing the premium over the closing stock price and the amount paid of $4.7 million under the First Investment Amendment and $13.6 million under the Second Investment Amendment were determined by the Company to represent consideration related to the Vifor Agreement and recorded as long-term deferred revenue in long-term liabilities on the unaudited condensed consolidated financial statements.

CSL Vifor agreed to a lock-up restriction not to sell the 2017 Shares or the 2022 Shares for a period of time following the effective date of the First Investment Agreement and Second Investment Agreement, respectively, which restriction with respect to the 2017 Shares has expired. The First Investment Agreement and the Second Investment Agreement each contain a customary standstill agreement.

In addition, the First Investment Agreement and Second Investment Agreement contain voting agreements made by CSL Vifor with respect to the 2017 Shares and 2022 Shares, respectively. The 2017 Shares and 2022 Shares have not been registered pursuant to the Securities Act of 1933, as amended, or the Securities Act, and were issued and sold in reliance upon the exemption from registration contained in Section 4(a)(2) of the Securities Act and Rule 506 promulgated thereunder as the transaction did not involve any public offering within the meaning of Section 4(a)(2) of the Securities Act. See Note 5 of the Notes to the Consolidated Financial Statements in the 2022 Annual Report on Form 10-K/A for a more detailed description of the Vifor Agreement.

The Company identified one performance obligation under the Vifor Agreement, as amended, the deliverable of the license. Thus until the license is delivered, the transaction price of $43.3 million which is comprised of the up-front payment of $25.0 million and the premiums paid by CSL Vifor on the First Investment Agreement and Second Investment Agreement of $4.7 million and $13.6 million, respectively, will remain in long-term deferred revenue in the accompanying unaudited condensed consolidated balance sheet.

Under the Vifor Agreement, these payments from CSL Vifor are non-refundable and non-creditable against any other amount due to the Company. In addition, if the Centers for Medicare & Medicaid Services, or CMS, determines that vadadustat is excluded from the Transitional Drug Add-on Payment Adjustment, or TDAPA, the Company can terminate the Vifor Agreement and will be required to repay the up-front payment of $25.0 million and the premiums paid by CSL Vifor of $18.3 million.

Fund, for the supply of vadadustat for the Vifor Territory already delivered or to be delivered to the Company through the end of 2023. The amount of the Working Capital Fund can be reviewed at specified intervals and may be adjusted based on a number of factors including outstanding supply commitments for vadadustat and agreed upon vadadustat inventory levels held by the Company for the Vifor Territory. Upon termination or expiration of the Vifor Agreement for any reason other than convenience by CSL Vifor (including following receipt of the CRL for vadadustat), the Company will be required to refund the outstanding balance of the Working Capital Fund on the date of termination or expiration.

The Company has determined the Working Capital Fund itself does not represent an obligation to transfer goods or services to CSL Vifor in the future and thus under ASC 606 was recorded as a refund liability. The refund liability is considered a debt arrangement with zero coupon interest and the Company imputes interest on the refund liability at a rate of 15.0% per annum, which was determined based on certain factors, including the Company's credit rating, comparable securities yield and the expected repayment period. On March 18, 2022, when the $40.0 million was received from CSL Vifor, the Company recorded an initial discount on the refund liability and a corresponding deferred gain on the condensed consolidated balance sheet. The discount on the refund liability is being amortized to interest expense using the effective interest method over the expected term of the Vifor Agreement. The deferred gain is being amortized to interest income on a straight-line basis over the expected term of the Vifor Agreement. The amortization of the discount was $0.7 million and $2.4 million for the three and nine months ended September 30, 2023, respectively, and $1.1 million and $2.3 million for the three and nine months ended September 30, 2022, respectively. The amortization of the deferred gain was $1.0 million and $3.0 million for the three and nine months ended September 30, 2023, respectively, and $0.9 million and $1.8 million for the three and nine months ended September 30, 2022, respectively. As of September 30, 2023, the $40.3 million refund liability is classified as a long-term liability based on management's estimated timing of the repayment of the refund liability to Vifor exceeding one-year.

The Company had a license agreement, which was amended from time to time, with Panion & BF Biotech, Inc., or Panion, under which Keryx Biopharmaceuticals, Inc., or Keryx, the Company's wholly owned subsidiary, was the contracting party, or Panion License Agreement, pursuant to which Keryx in-licensed the exclusive worldwide rights, excluding certain Asian-Pacific countries, or Licensor Territory, for the development and commercialization of ferric citrate.

On April 17, 2019, the Company and Panion entered into a second amended and restated license agreement, or Panion Amended License Agreement, which amends and restates in full the Panion License Agreement, effective as of April 17, 2019. The Panion Amended License Agreement provides Keryx with an exclusive license under Panion-owned know-how and patents with the right to sublicense, develop, make, use, sell, offer for sale, import and export ferric citrate worldwide, excluding the Licensor Territory. The Panion Amended License Agreement also provides Panion with an exclusive license under the Keryx-owned patents, with the right to sublicense (with the Company’s written consent), develop, make, use, sell, offer for sale, import and export ferric citrate in certain countries in the Licensor Territory. Under the Panion Amended License Agreement, Panion is eligible to receive from the Company or any sublicensee royalty payments based on a mid-single digit percentage of sales of ferric citrate in the Company’s licensed territories. The Company is eligible to receive from Panion or any sublicensee royalty payments based on a mid-single digit percentage of net sales of ferric citrate in Panion’s licensed territories. See Note 5 of the Notes to the Consolidated Financial Statements in the 2022 Annual Report on Form 10-K/A for a more detailed description of this license agreement.

The Company recognized royalty payments due to Panion of approximately $3.1 million and $9.3 million during the three and nine months ended September 30, 2023, respectively, and $2.9 million and $9.5 million during the three and nine months ended September 30, 2022, respectively, relating to the Company’s sales of Auryxia in the United States and JT and Torii’s net sales of Riona in Japan.

The Company has an Amended and Restated Sublicense Agreement, which was amended in June 2013, with JT and Torii, or JT and Torii Sublicense Agreement, under which Keryx, the Company’s wholly owned subsidiary, remains the contracting party. Under the JT and Torii Sublicense Agreement, JT and Torii obtained the exclusive sublicense rights for the development and commercialization of ferric citrate hydrate in Japan. JT and Torii are responsible for the future development and commercialization costs in Japan. See Note 5 of the Notes to the Consolidated Financial Statements in the 2022 Annual Report on Form 10-K/A for a more detailed description of this sublicense agreement.

The Company identified two performance obligations in connection with its obligations under the JT and Torii Sublicense Agreement: (i) License and Supply Performance Obligation and (ii) Rights to Future Know-How Performance Obligation. The Company allocated the transaction price to each performance obligation based on the Company’s best estimate of the relative standalone selling price. The Company developed a best estimate of the standalone selling price for the Rights to Future Know-How Performance Obligation primarily based on the likelihood that additional intellectual property covered by the license conveyed will be developed during the term of the arrangement and determined it immaterial. As such, the

The Company recognized license revenue of $1.4 million and $4.0 million during the three and nine months ended September 30, 2023, respectively, and $1.2 million and $3.9 million during the three and nine months ended September 30, 2022, respectively, related to royalties earned on net sales of Riona in Japan. The Company records the associated mid-single digit percentage of net sales royalty expense due to Panion, the licensor of Riona, in the same period as the royalty revenue from JT and Torii is recorded.

On December 22, 2022, the Company and Averoa SAS, or Averoa, entered into a license agreement, or Averoa License Agreement, pursuant to which the Company granted to Averoa an exclusive license to develop and commercialize ferric citrate, or Averoa Licensed Product, in the European Economic Area, Turkey, Switzerland and the United Kingdom, or Averoa Territory.

Under the Averoa License Agreement, the Company is entitled to receive tiered escalating royalties ranging from a mid-single digit percentage to a low double-digit percentage of Averoa's annual net sales in the Averoa Territory, including certain minimum royalty amounts in certain years, and subject to reduction in certain circumstances. The Company and Averoa have established a joint steering committee to oversee the development, manufacturing and commercialization of the Averoa Licensed Product in the Averoa Territory. The Averoa License Agreement expires on the date of expiration of all royalty obligations due thereunder with respect to the Averoa Licensed Product on a country-by-country basis in the Averoa Territory, unless earlier terminated in accordance with the Averoa License Agreement.

The Averoa License Agreement provides that the Company and Averoa will enter into a supply agreement pursuant to which the Company will supply the Averoa Licensed Product to Averoa for commercial use in the Averoa Territory. The Company will have the right to terminate the supply agreement upon 24 months' notice, which may be provided on or after January 1, 2024. As of September 30, 2023, the Company and Averoa have not yet entered into a supply agreement.

On May 24, 2023, or Medice Effective Date, the Company and Medice entered into the Medice License Agreement, pursuant to which the Company granted to Medice an exclusive license to develop and commercialize vadadustat, or Medice Licensed Product, for the treatment of anemia in adult patients with chronic kidney disease in the Medice Territory.

The royalties will expire on a country-by-country basis upon the latest to occur of (a) the date of expiration of the last-to-expire valid claim of any Company, Medice or joint patent that covers the Medice Licensed Product in such country in the Medice Territory, (b) the date of expiration of data or regulatory exclusivity for the Medice Licensed Product in such country in the Medice Territory and (c) the date that is 12 years from first commercial sale of the Medice Licensed Product in such country in the Medice Territory.

Under the Medice License Agreement, the Company retains the right to develop the Medice Licensed Product for non-dialysis patients with anemia due to chronic kidney disease in the Medice Territory. If the Company develops the Medice Licensed Product for non-dialysis patients and such Medice Licensed Product receives marketing approval in the Medice Territory, Medice will commercialize the Medice Licensed Product for both indications in the Medice Territory. In this instance, the Company would receive 70% of the net product margin of any sales of the Medice Licensed Product in the non-dialysis patient population, unless Medice requests to share the cost of the development necessary to gain approval to market the Medice Licensed Product for non-dialysis patients in the Medice Territory and the parties agree on alternative financial terms. If the Company develops the licensed product for non-dialysis patients, the Company has determined that the activities under the Medice License Agreement represent joint operating activities in which both parties are active participants and of which both parties are exposed to significant risks and rewards that are dependent on the success of the activities. Accordingly, if the Company develops the Medice Licensed Product for non-dialysis patients the Company will account for the joint activities in accordance with ASC No. 808, Collaborative Arrangements, or ASC 808. Additionally, the Company has determined that in the

context of the development of the Medice Licensed Product for non-dialysis patients, Medice does not represent a customer as contemplated by ASC 606-10-15, Revenue from Contracts with Customers – Scope and Scope Exceptions. As a result, the activities conducted pursuant to development activities for the Medice Licensed Product for non-dialysis patients will be accounted for as a component of the related expense in the period incurred.

The Medice License Agreement expires on the date of expiration of all payment obligations due thereunder with respect to the Medice Licensed Product in the last country in the Medice Territory, unless earlier terminated in accordance with the terms of the Medice License Agreement. Either party may, subject to a cure period, terminate the Medice License Agreement in the event of the other party's uncured material breach. Medice has the right to terminate the Medice License Agreement in its entirety for convenience upon 12 months' prior written notice delivered on or after the date that is 12 months after the Medice Effective Date.

The Medice License Agreement includes customary terms relating to, among others, indemnification, confidentiality, remedies, and representations and warranties. The Medice License Agreement provides that the Company and Medice will enter into a supply agreement pursuant to which the Company will supply the Medice Licensed Product to Medice for commercial use in the Medice Territory.

The Company evaluated the elements of the Medice License Agreement in accordance with the provisions of ASC 606 and concluded Medice is a customer. The Company's arrangement with Medice contains one material promise under the contract at inception, which is the exclusive license under the Company's intellectual property to develop and commercialize the Medice Licensed Product in the Medice Territory during the term of the Medice License Agreement and use the Akebia Trademark solely in connection with the commercialization of the Medice Licensed Product, or License Deliverable.

The Company identified one performance obligation in connection with its obligations under the Medice License Agreement, which is the License Deliverable, or License Performance Obligation. The transaction price at inception was comprised of the up-front payment of $10.0 million, of which the Company received $8.6 million during the quarter ended June 30, 2023. The remaining $1.4 million was withheld by the German Federal Tax Office and is included in other long-term assets on the condensed consolidated balance sheet as of September 30, 2023.

Pursuant to the terms of the Medice License Agreement, the up-front payment of $10.0 million is non-refundable and non-creditable against any other amount due to the Company and was allocated to the License Performance Obligation, which was satisfied as of the Medice Effective Date. As such, the Company recognized the $10.0 million up-front payment as License, collaboration and other revenue in the condensed consolidated statement of operations and comprehensive loss during the nine months ended September 30, 2023.

On December 18, 2016, the Company entered into a collaboration and license agreement, or Otsuka U.S. Agreement, with Otsuka Pharmaceutical Co. Ltd., or Otsuka. The collaboration was focused on the development and commercialization of vadadustat in the United States. The Company was responsible for leading the development of vadadustat, for which it submitted an NDA to the FDA in March 2021, and for which it received the CRL in March 2022.

The Company did not recognize collaboration revenue with respect to the Otsuka U.S. Agreement during the three months ended September 30, 2023 or 2022. During the nine months ended September 30, 2022, the Company recognized collaboration revenue totaling $86.8 million with respect to the Otsuka U.S. Agreement. During the nine months ended September 30, 2023, the Company recognized $2.2 million in collaboration revenue in connection with the Packaging Validation Transfer Agreement entered into with Otsuka on April 20, 2023. The Company evaluated the agreement under ASC

On April 25, 2017, the Company entered into the Otsuka International Agreement. The collaboration was focused on the development and commercialization of vadadustat in Europe, Russia, China, Canada, Australia, the Middle East and certain other territories, collectively, the Otsuka International Territory. As discussed above, the Otsuka International Agreement was terminated on June 30, 2022 pursuant to the Termination Agreement.

During the three and nine months ended September 30, 2022, the Company recognized no collaboration revenue and $5.5 million with respect to the Otsuka International Agreement, respectively. A more detailed description of this collaboration agreement and the Company's evaluation of this agreement under ASC 606 can be found in Note 5 of the Notes to the Consolidated Financial Statements in the 2022 Annual Report on Form 10-K/A.