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Significant Accounting Policies (Policies) | 6 Months Ended
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Jun. 30, 2025
Accounting Policies [Abstract] |
Description of Operations | Description of Operations FibroGen, Inc. (“FibroGen” or the “Company”) is a biopharmaceutical company focused on development of novel therapies at the frontiers of cancer biology and anemia. The Company is developing FG-3246, a potential first-in-class antibody-drug conjugate (“ADC”) targeting CD46, for the treatment of metastatic castration-resistant prostate cancer (“mCRPC”) and potentially other cancers. This program also includes the development of FG-3180, an associated CD46-targeted positron emission tomography (“PET”) biomarker and imaging agent. The Company anticipates initiation of a Phase 2 monotherapy dose optimization study of FG-3246 for the treatment of mCRPC, along with the exploratory analysis of FG-3180, in the third quarter of 2025, pending close of the sale of FibroGen International to AstraZeneca Treasury Limited. The Company and its collaboration partners have developed roxadustat (爱瑞卓®, EVRENZOTM), which is currently approved in the People’s Republic of China (“China”), Europe, Japan, and numerous other countries for the treatment of anemia in chronic kidney disease (“CKD”) patients on dialysis and not on dialysis. On February 20, 2025, the Company entered into a share purchase agreement (the “Share Purchase Agreement”) with AstraZeneca Treasury Limited pursuant to which FibroGen and its subsidiary FibroGen China Anemia Holdings, Ltd. agreed to sell all of the issued and outstanding equity interests of FibroGen International (Hong Kong) Ltd. (“FibroGen International”) to AstraZeneca Treasury Limited. AstraZeneca AB (“AstraZeneca”) is the Company’s long-time commercialization partner for roxadustat in greater China and South Korea. This sale includes all of FibroGen’s roxadustat assets in China, including FibroGen International’s subsidiary FibroGen (China) Medical Technology Development Co., Ltd (“FibroGen Beijing”) and its 51.1% interest in Beijing Falikang Pharmaceutical Co., Ltd. (“Falikang”). The transaction is expected to close in the third quarter of 2025, and is subject to customary closing conditions and closing deliverables, including receipt of regulatory approval from the China State Administration for Market Regulation (“SAMR”). FibroGen has retained the rights to roxadustat in the United States of America (“U.S.”), Canada, Mexico, and in all markets not held by AstraZeneca or licensed to Astellas Pharma Inc. (“Astellas”). Roxadustat is not approved for commercialization in any indication in the U.S., Canada, or Mexico. Astellas is commercializing roxadustat (EVRENZOTM) in Europe and Japan to treat anemia under two development and commercialization license agreements: one for Japan, and one for Europe, the Commonwealth of Independent States, the Middle East and South Africa. The Company continues to work on its development plan for roxadustat in anemia associated with lower-risk myelodysplastic syndromes (“MDS”), a high-value indication with significant unmet medical need.
Basis of Presentation and Principles of Consolidation | Basis of Presentation and Principles of Consolidation The unaudited condensed consolidated financial statements and related disclosures have been prepared in accordance with accounting principles generally accepted in the United States (“U.S. GAAP”) applicable to interim financial reporting and with the instructions to Form 10-Q and Rule 10-01 of Regulation S-X of the U.S. Securities and Exchange Commission (“SEC”) and, therefore, do not include all information and footnote disclosures normally included in the annual consolidated financial statements. The financial information included herein should be read in conjunction with the consolidated financial statements and related notes in the Company’s Annual Report on Form 10-K for the year ended December 31, 2024, filed on March 17, 2025. The condensed consolidated financial statements include the accounts of FibroGen, its wholly-owned subsidiaries and its majority-owned subsidiaries, as well as any variable interest entity (“VIE”) for which FibroGen is the primary beneficiary. All inter-company transactions and balances have been eliminated in consolidation. The Company operates as one reportable segment — the development and commercialization of novel therapeutics to treat serious unmet medical needs.
Discontinued Operations | Discontinued Operations On February 20, 2025, the Company entered into the Share Purchase Agreement with AstraZeneca Treasury Limited pursuant to which FibroGen and its subsidiary FibroGen China Anemia Holdings, Ltd. agreed to sell all of the issued and outstanding equity interests of FibroGen International to AstraZeneca Treasury Limited for an aggregate purchase price comprised of $85 million in cash for the enterprise value of FibroGen International, plus an additional cash amount equal to the net cash held in China by FibroGen International and its subsidiaries as of the closing. This sale includes all of FibroGen’s roxadustat assets in China, including FibroGen International’s subsidiary FibroGen Beijing and its 51.1% interest in Falikang. The transaction is expected to close in the third quarter of 2025, and is subject to customary closing conditions and closing deliverables, including receipt of regulatory approval from the China SAMR. The Company analyzed the quantitative and qualitative factors and concluded that the sale of FibroGen International represents a strategic shift in FibroGen’s business and qualified as a discontinued operation. As a result, the Company determined that FibroGen International met the “held for sale” criteria and the “discontinued operations” criteria in accordance with Financial Accounting Standard Board (“FASB”) Accounting Standards Codification (“ASC”) 205, Presentation of Financial Statements, as of June 30, 2025 and December 31, 2024. Accordingly, the condensed consolidated balance sheets and the condensed consolidated statements of operations, and the notes to the condensed consolidated financial statements were recasted for all periods presented to reflect the discontinuation of FibroGen International in accordance with ASC 205. The operating results related to FibroGen International are classified as discontinued operations, and have been reflected as discontinued operations in the condensed consolidated statements of operations, while the related assets and liabilities were classified within the condensed consolidated balance sheets as held for sale for all periods presented. See Note 2, Discontinued Operations, for related disclosures. Unless otherwise noted, discussion in the notes to these consolidated financial statements, relates to solely to the Company’s continuing operations.
Reverse Stock Split | Reverse Stock Split On June 16, 2025, the Company effected a 1-for-25 reverse stock split (the “Reverse Stock Split”). The Reverse Stock Split reduced the number of issued and outstanding shares of common stock from approximately 101.1 million shares to approximately 4.0 million shares. Proportionate adjustments have been made to the number of shares available for issuance under the Company’s equity incentive plans as well as outstanding equity awards, in accordance with their respective terms. All share amounts have been retroactively adjusted in the condensed consolidated financial statements and the notes to the condensed consolidated financial statements, where applicable, to reflect the Reverse Stock Split.
Liquidity and Going Concern | Liquidity and Going Concern The unaudited condensed consolidated financial statements are prepared in accordance with the U.S. GAAP applicable to a going concern, which contemplates the realization of assets and the satisfaction of liabilities in the normal course of business and does not include any adjustments relating to the recoverability and classification of recorded asset amounts or the amounts and classification of liabilities that might result from the outcome of the uncertainties described below. If the Company is unable to complete the above mentioned sale of FibroGen International, access additional cash from its China operations, or raise additional capital in the U.S., the Company would not have sufficient liquidity to continue operations in the U.S. for the 12 months from the date that the financial statements are issued and would not be able to comply with its financial covenant that requires a minimum balance of $18.75 million of unrestricted cash and cash equivalents to be held in accounts in the United States. Upon an event of default, the Company’s senior secured term loan facilities could become immediately due and payable. The Company has evaluated measures to access additional cash from its China operations and believes the sale of FibroGen International represents the most efficient way to access the entirety of its cash from China upon closing of the transaction. There is also the potential that the Company raises additional funds in the U.S. at any time through equity, equity-linked, or debt financing arrangements or from other sources. There can be no assurances that these plans will be successful. As a result of these factors, the Company has determined that there is substantial doubt about its ability to continue as a going concern within 12 months after the date that the financial statements are issued.
Use of Estimates | Use of Estimates The preparation of the condensed consolidated financial statements in conformity with U.S. GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the financial statements and reported amounts of revenues and expenses during the reporting period. The more significant areas requiring the use of management estimates and assumptions include valuation and recognition of revenue and deferred revenue, specifically, estimates in variable consideration for drug product sales, and estimates in transaction price per unit for the China performance obligation. On an ongoing basis, management reviews these estimates and assumptions. Changes in facts and circumstances may alter such estimates and actual results could differ from those estimates. In the Company’s opinion, the accompanying unaudited condensed consolidated financial statements include all normal recurring adjustments necessary for a fair statement of its financial position, results of operations and cash flows for the interim periods presented.
Net Loss per Share | Net Income (Loss) per Share Potential common shares that would have the effect of increasing diluted earnings per share are considered to be anti-dilutive and as such, these shares are not included in the calculation of diluted earnings per share. The Company reported a loss from continuing operations for each of the three and six months ended June 30, 2025 and 2024. Therefore, dilutive common shares are not assumed to have been issued since their effect is anti-dilutive for these periods. Diluted weighted average shares excluded the following potential common shares related to stock options, service-based restricted stock units (“RSUs”), performance-based RSUs (“PRSUs”), total shareholder return (“TSR”) awards and shares to be purchased under the 2014 Employee Stock Purchase Plan (“ESPP”) for the periods presented as they were anti-dilutive (in thousands):
|  | Three Months Ended June 30, |  |  | Six Months Ended June 30, |
|  | 2025 |  |  | 2024 |  |  | 2025 |  |  | 2024 |
Employee stock options |  |  | 490 |  |  |  | 603 |  |  |  | 500 |  |  |  | 551 |
RSUs, PRSUs and TSR awards |  |  | 36 |  |  |  | 156 |  |  |  | 42 |  |  |  | 157 |
ESPP |  |  | — |  |  |  | 18 |  |  |  | — |  |  |  | 20 |
|  |  | 526 |  |  |  | 777 |  |  |  | 542 |  |  |  | 728 |
Risks and Uncertainties | Risks and Uncertainties The Company’s future results of operations involve a number of risks and uncertainties. Factors that could affect the Company’s future operating results and cause actual results to vary materially from expectations include, but are not limited to, the results of clinical trials and the achievement of milestones, research developments, actions by regulatory authorities, market acceptance of the Company’s product candidates, competition from other products and larger companies, the liquidity and capital resources of the Company, intellectual property protection for the Company’s proprietary technology, strategic relationships, and dependence on key individuals, suppliers, clinical organization, and other third parties.
Recently Issued Accounting Guidance Not Yet Adopted | Recently Issued Accounting Guidance Not Yet Adopted In November 2024, the FASB issued Accounting Standards Update (“ASU”) 2024-03, Income Statement - Reporting Comprehensive Income - Expense Disaggregation Disclosures (Subtopic 220-40), and relevantly in January 2025, the FASB issued ASU 2025-01, Income Statement - Reporting Comprehensive Income - Expense Disaggregation Disclosures (Subtopic 220-40): Clarifying the Effective Date. The guidance requires entities to disaggregate operating expenses into specific categories to provide enhanced transparency into the nature and function of expenses. This guidance is effective for fiscal years beginning after December 15, 2026, and for interim periods within fiscal years beginning after December 15, 2027, with early adoption permitted. This guidance should be applied either prospectively to financial statements issued for reporting periods after the effective date or retrospectively to any or all prior periods presented in the financial statements. The Company is currently in the process of evaluating the effects of this guidance on its related disclosures. In December 2023, the FASB issued ASU 2023-09, Income Taxes (Topic 740): Improvements to Income Tax Disclosures, which requires enhanced income tax disclosures, including specific categories and disaggregation of information in the effective tax rate reconciliation, disaggregated information related to income taxes paid, income or loss from continuing operations before income tax expense or benefit, and income tax expense or benefit from continuing operations. This guidance is effective for annual periods beginning after December 15, 2024, with early adoption permitted. The Company is currently in the process of evaluating the impact of this pronouncement on its related disclosures.
Collaboration Arrangements and Revenues | Astellas Agreements Astellas Japan Agreement In June 2005, the Company entered into a collaboration agreement with Astellas for the development and commercialization (but not manufacture) of roxadustat for the treatment of anemia in Japan (“Astellas Japan Agreement”). Under this agreement, Astellas agreed to pay license fees, other upfront consideration and various milestone payments, totaling $172.6 million. The Astellas Japan Agreement also provides for tiered payments based on net sales of product (as defined) in the low 20% range of the list price published by Japan’s Ministry of Health, Labour and Welfare, adjusted for certain elements, after commercial launch. The aggregate amount of consideration received under the Astellas Japan Agreement through June 30, 2025 totaled $105.1 million, excluding drug product revenue that is discussed under the Drug Product Revenue, Net section below. Based on its current development plans for roxadustat in Japan, the Company does not expect to receive most or all of the additional potential milestones under the Astellas Japan Agreement. Amounts recognized as license revenue and development revenue under the Astellas Japan Agreement were not material for the three and six months ended June 30, 2025 and 2024. The transaction price related to consideration received through June 30, 2025 and accounts receivable has been allocated to each of the performance obligations under the Astellas Japan Agreement, including $100.3 million for license and $17.1 million for co-development. There was no license revenue or development revenue resulting from changes to estimated variable consideration in the current period relating to performance obligations satisfied or partially satisfied in previous periods for the three months ended June 30, 2025 under the Astellas Japan Agreement. The Company does not expect material variable consideration from estimated future co-development billing beyond the development period in the transaction price related to the Astellas Japan Agreement. In 2018, FibroGen and Astellas entered into an amendment to the Astellas Japan Agreement that allows Astellas to manufacture roxadustat drug product for commercialization in Japan (the “Astellas Japan Amendment”). The related drug product revenue is described under the Drug Product Revenue, Net section below. Astellas Europe Agreement In April 2006, the Company entered into a separate collaboration agreement with Astellas for the development and commercialization of roxadustat for the treatment of anemia in Europe, the Middle East, the Commonwealth of Independent States and South Africa (“Astellas Europe Agreement”). Under the terms of the Astellas Europe Agreement, Astellas agreed to pay license fees, other upfront consideration and various milestone payments, totaling $745.0 million. Under the Astellas Europe Agreement, Astellas committed to fund 50% of joint development costs for Europe and North America, and all territory-specific costs. The Astellas Europe Agreement also provides for tiered payments based on net sales of product (as defined) in the low 20% range. The aggregate amount of consideration received under the Astellas Europe Agreement through June 30, 2025 totaled $685.0 million, excluding drug product revenue that is discussed under the Drug Product Revenue, Net section below. Based on its current development plans for roxadustat in Europe, the Company does not expect to receive most or all of the additional potential milestones under the Astellas Europe Agreement. Amounts recognized as license revenue and development revenue under the Astellas Europe Agreement were not material for the three and six months ended June 30, 2025 and 2024. The transaction price related to consideration received through June 30, 2025 and accounts receivable has been allocated to each of the performance obligations under the Astellas Europe Agreement, including $619.0 million for license and $288.4 million for co-development. There was no license revenue or development revenue resulting from changes to estimated variable consideration in the current period relating to performance obligations satisfied or partially satisfied in previous periods for three months ended June 30, 2025 under the Astellas Europe Agreement. The Company does not expect material variable consideration from estimated future co-development billing beyond the development period in the transaction price related to the Astellas Europe Agreement. In 2021, the Company entered into an EU Supply Agreement with Astellas under the Astellas Europe Agreement (“Astellas EU Supply Agreement”) to define general forecast, order, supply and payment terms for Astellas to purchase roxadustat bulk drug product from FibroGen in support of commercial supplies. The related drug product revenue is described under the Drug Product Revenue, Net section below. AstraZeneca Agreements AstraZeneca U.S./Rest of World (“RoW”) Agreement Effective July 30, 2013, the Company entered into a collaboration agreement with AstraZeneca for the development and commercialization of roxadustat for the treatment of anemia in the U.S. and all other countries in the world, other than China, not previously licensed under the Astellas Europe and Astellas Japan Agreements (“AstraZeneca U.S./RoW Agreement”). On February 23, 2024, the Company and AstraZeneca entered into an agreement to terminate the AstraZeneca U.S./RoW Agreement, effective as of February 25, 2024 (“AstraZeneca Termination and Transition Agreement”). Pursuant to the AstraZeneca Termination and Transition Agreement, AstraZeneca returns all of their non-China roxadustat rights to the Company, with the exception of South Korea, and provides certain assistance during a transition period. In addition, as a part of this AstraZeneca Termination and Transition Agreement, AstraZeneca will receive tiered mid-single digit royalties on FibroGen’s sales of roxadustat in the terminated territories, or thirty-five percent of all revenue FibroGen receives if it licenses or sells such rights to a third-party. Neither party incurred any early termination penalties. The aggregate amount of consideration for milestone and upfront payments received under the AstraZeneca U.S./RoW Agreement through the termination totaled $439.0 million, excluding drug product revenue under the Master Supply Agreement with AstraZeneca under the AstraZeneca U.S./RoW Agreement (“AstraZeneca Master Supply Agreement”), entered in 2020, which is described under the Drug Product Revenue, Net section below. In addition, resulting from the AstraZeneca Termination and Transition Agreement, the Company and AstraZeneca settled the outstanding balances relating to past transactions under the AstraZeneca Master Supply Agreement. Accordingly, during the first quarter of 2024, the Company accounted for the termination of the AstraZeneca U.S./RoW agreement as a contract modification under the ASC 606, Revenue from Contracts with Customers (“ASC 606”) and recorded a cumulative catch-up adjustment as described under the Drug Product Revenue, Net section below. The Company’s collaboration agreement with AstraZeneca for roxadustat in China, as described below, remains in place. AstraZeneca China Agreement Effective July 30, 2013, the Company (through its subsidiaries affiliated with China) entered into a collaboration agreement with AstraZeneca for roxadustat for the treatment of anemia in China (“AstraZeneca China Agreement”). Under the terms of the AstraZeneca China Agreement, AstraZeneca agreed to pay upfront consideration and potential milestone payments, totaling $376.7 million. The AstraZeneca China Agreement is structured as a 50/50 profit or loss share (as defined), which was amended under the AstraZeneca China Amendment as defined and discussed below, and provides for joint development costs (including capital and equipment costs for construction of the manufacturing plant in China), to be shared equally during the development period. The aggregate amount of such consideration received for milestone and upfront payments through June 30, 2025 totaled $81.2 million. AstraZeneca China Amendment In July 2020, FibroGen China Anemia Holdings, Ltd., FibroGen Beijing, FibroGen International, and AstraZeneca entered into an amendment to the AstraZeneca China Agreement, relating to the development and commercialization of roxadustat in China (the “AstraZeneca China Amendment”). Under the AstraZeneca China Amendment, in 2020, FibroGen Beijing and AstraZeneca completed the establishment of a jointly owned entity, Falikang, which performs roxadustat distribution, as well as conducts sales and marketing through AstraZeneca. Substantially all direct roxadustat product sales to distributors in China are made by Falikang, while FibroGen Beijing continues to sell roxadustat product directly in limited areas in China. FibroGen Beijing manufactures and supplies commercial product to Falikang based on a gross transfer price, which is adjusted for the estimated profit share. Further discussion related to the sales to Falikang is discussed under the China Performance Obligation section below. The related net product revenue recognized from the sales to Falikang was $16.4 million and $46.0 million for the three months ended June 30, 2025 and 2024, and $53.3 million and $73.1 million for the six months ended June 30, 2025 and 2024, respectively, which were included in the discontinued operations in the condensed consolidated statements of operations together with the sales directly to distributors, resulting from the Share Purchase Agreement with AstraZeneca Treasury Limited as discussed in Note 2, Discontinued Operations. Prior to the above-mentioned termination of the AstraZeneca U.S./RoW Agreement, the Company evaluated under the ASC 606 and accounted for the AstraZeneca U.S./RoW Agreement and the AstraZeneca China Agreement as a single arrangement with the presumption that two or more agreements executed with a single customer at or around the same time should be presumed to be a single arrangement. As a result of the termination of the AstraZeneca U.S./RoW Agreement, during the first quarter of 2024, the Company recorded the final development revenue under the AstraZeneca U.S./RoW Agreement and AstraZeneca China Agreement, which was immaterial. The transaction price related to consideration received and accounts receivable through the termination of the AstraZeneca U.S./RoW Agreement has been allocated to each of the performance obligations under the AstraZeneca U.S./RoW Agreement and AstraZeneca China Agreement, including $344.5 million for license, $625.5 million for co-development, information sharing and committee services, and $551.1 million for China performance obligation (with cumulative revenue of $408.1 million through June 30, 2025) that is recognized as product revenue, net included in discontinued operations as described under China Performance Obligation section below.
Product Revenue, Net | Product revenue, net, which is included in the discontinued operations, consists primarily of revenues from sales of roxadustat commercial product to Falikang. Substantially all direct roxadustat product sales to distributors in China are made by Falikang. FibroGen Beijing manufactures and supplies commercial product to Falikang. The net transaction price for FibroGen Beijing’s product sales to Falikang is based on a gross transaction price, adjusted for the estimated profit share. The roxadustat sales to Falikang marked the beginning of the Company’s China performance obligation under the Company’s agreements with AstraZeneca. Product revenue is based on the transaction price of the China performance obligation. Revenue is recognized when control of the product is transferred to Falikang, in an amount that reflects the allocation of the transaction price to the performance obligation satisfied during the reporting period. Periodically, the Company updates its assumptions such as total sales quantity, timing of China’s volume-based purchasing program, performance period, gross transaction price, profit share and other inputs including foreign currency translation impact, among others. The China Health Authority has accepted abbreviated new drug applications for over 20 generics roxadustat applicants and approved multiple for marketing in China, since roxadustat’s inclusion in the 2023 National Reimbursement Drug List. In July 2025, roxadustat was announced as being included in the 11th round of the China’s volume-based purchasing program whereby a national tender has been called. Any net transaction price in excess of the revenue recognized is added to the deferred balance to date, and will be recognized in future periods as the performance obligation is satisfied. While the related product revenue recognized is included in discontinued operations, as of June 30, 2025 and December 31, 2024, the related deferred revenues were not included in the disposal group held for sale as the related obligation to AstraZeneca will be satisfied upon the closing of the divestiture of FibroGen International. The following table includes a roll-forward of the related deferred revenue that is considered as a contract liability (in thousands):
|  | Balance at December 31, 2024 |  |  | Additions |  |  | Recognized as Revenue (Discontinued Operations) |  |  | Currency Translation and Other |  |  | Balance at June 30, 2025 |
AstraZeneca China performance obligation - deferred revenue |  | $ | (132,097 | ) |  | $ | (63,509 | ) |  | $ | 53,308 |  |  | $ | (649 | ) |  | $ | (142,947 | )
Deferred revenue includes amounts allocated to the China performance obligation under the AstraZeneca arrangement as revenue recognition associated with this unit of accounting is tied to the commercial launch of the products within China and to when the control of the manufactured commercial products is transferred to AstraZeneca. As of June 30, 2025, approximately $20.7 million of the above deferred revenue related to the China unit of accounting was included in short-term deferred revenue, which represents the amount of deferred revenue associated with the China unit of accounting that is expected to be recognized within the next 12 months, associated with the commercial sales in China.
Drug Product Revenue, Net | Drug Product Revenue, Net Drug product revenue from commercial-grade active pharmaceutical ingredient (“API”) or bulk drug product sales to Astellas and AstraZeneca was as follows for the three and six months ended June 30, 2025 and 2024 (in thousands):
|  | Three Months Ended June 30, |  |  | Six Months Ended June 30, |
|  | 2025 |  |  | 2024 |  |  | 2025 |  |  | 2024 |
Astellas Japan Agreement |  | $ | 44 |  |  | $ | (366 | ) |  | $ | 1,825 |  |  | $ | (2,571 | )
Astellas Europe Agreement |  |  | 1,171 |  |  |  | 1,095 |  |  |  | 1,986 |  |  |  | 2,116 |
AstraZeneca U.S./RoW Agreement |  |  | — |  |  |  | — |  |  |  | — |  |  |  | 25,671 |
Drug product revenue, net |  | $ | 1,215 |  |  | $ | 729 |  |  | $ | 3,811 |  |  | $ | 25,216 |
Astellas Japan Agreement The Company updates its estimate of variable consideration related to the API shipments fulfilled under the terms of Astellas Japan Amendment at each balance sheet date. The adjustment to the drug product revenue for the three months ended June 30, 2025 was immaterial. For the three months ended March 31, 2025, the Company updated its estimate of variable consideration related to the API shipments fulfilled under the terms of Astellas Japan Amendment, and accordingly recorded an adjustment to the drug product revenue of $1.8 million. Specifically, the change in estimated variable consideration was based on the API held by Astellas at period end, adjusted to reflect the changes in the estimated yield from the manufacture of bulk product tablets, among others. For the three months ended June 30, 2024, the Company updated its estimate of variable consideration related to the API shipments fulfilled under the terms of Astellas Japan Amendment, and accordingly recorded a reduction to the drug product revenue of $0.4 million Specifically, the change in estimated variable consideration was based on the API held by Astellas at period end, adjusted to reflect foreign exchange impacts and the changes in the estimated bulk product strength mix intended to be manufactured by Astellas, among others. For the three months ended March 31, 2024, the Company updated its estimate of variable consideration related to the API shipments fulfilled under the terms of Astellas Japan Amendment, and accordingly recorded a reduction to the drug product revenue of $2.2 million. Specifically, the change in estimated variable consideration was based on the API held by Astellas at period end, adjusted to reflect the changes in the estimated bulk product strength mix intended to be manufactured by Astellas, and foreign exchange impacts, among others. As of June 30, 2025, the balances related to the API price true-up under the Astellas Japan Agreement were $0.6 million in accrued liabilities, representing the Company’s best estimate of the timing for these amounts to be paid. As of December 31, 2024, the balances related to the API price true-up under the Astellas Japan Agreement were $2.5 million in accrued liabilities and $0.6 million in other long-term liabilities. Astellas Europe Agreement The Company transferred bulk drug product for commercial purposes under the terms of the Astellas Europe Agreement and the Astellas EU Supply Agreement in the prior years. The Company recognized the related fully burdened manufacturing costs as drug product revenue in the respective periods and recorded the constrained transaction price in deferred revenue due to a high degree of uncertainty associated with the variable consideration for revenue recognition purposes. The Company updates its estimate of variable consideration related to the bulk drug product transferred in prior years at each balance sheet date. During the fourth quarter of 2024, the Company transferred bulk drug product for commercial purposes under the terms of the Astellas Europe Agreement and the Astellas EU Supply Agreement, and recognized the related fully-burdened manufacturing costs of $0.6 million as drug product revenue, and recorded $4.4 million as deferred revenue due to a high degree of uncertainty associated with the variable consideration for revenue recognition purposes. In addition, the Company updated its estimate of variable consideration related to the bulk drug product transferred in prior years. Specifically, the change in estimated variable consideration was based on the bulk drug product held by Astellas at the period end, adjusted to reflect the changes in the estimated transfer price, forecast information, shelf-life estimates and other items. As a result, for the year ended December 31, 2024, the Company reclassified $7.2 million from the related deferred revenue to accrued liabilities. As of December 31, 2024, the related balance in accrued liabilities was $10.5 million. Further for the six months ended June 30, 2025, the Company reclassified $1.3 million from the related deferred revenue to accrued liabilities. As of June 30, 2025, the balances related to the bulk drug product price true-up under the Astellas Europe Agreement and the Astellas EU Supply Agreement were $11.9 million in accrued liabilities, representing the Company’s best estimate that these amounts will be paid within the next 12 months. The Company recognized royalty revenue of $1.2 million and $1.1 million as drug product revenue from the deferred revenue under the Astellas Europe Agreement for the three months ended June 30, 2025 and 2024, and $2.0 million and $2.1 million for the six months ended June 30, 2025 and 2024, respectively. It is the Company’s best estimate that the remainder of the deferred revenue will be recognized as revenue when uncertainty is resolved, based on the performance of roxadustat product sales in the Astellas territory. The following table includes a roll-forward of the above-mentioned deferred revenues that are considered as contract liabilities related to drug product (in thousands):
|  | Balance at December 31, 2024 |  |  | Recognized as Revenue |  |  | Reclassified to Accrued Liability / Accounts Payable |  |  | Balance at June 30, 2025 |
Drug product revenue - deferred revenue: |  |  |  |  |  |  |  |  |  |  |  |
Astellas Europe Agreement |  | $ | (9,901 | ) |  | $ | 1,986 |  |  | $ | 1,327 |  |  | $ | (6,588 | )
AstraZeneca U.S./RoW Agreement As described under AstraZeneca Agreements section above, pursuant to the AstraZeneca Termination and Transition Agreement related to the AstraZeneca U.S./RoW Agreement, the Company and AstraZeneca settled the outstanding balances relating to past transactions under the AstraZeneca Master Supply Agreement. Accordingly, during the first quarter of 2024, the Company accounted for the termination of the AstraZeneca U.S./RoW agreement as a contract modification under the ASC 606 and recorded a cumulative catch-up net adjustment of $25.7 million to the drug product revenue and received the cash during the second quarter of 2024. Corresponding to the drug product revenue, during the first quarter of 2024, the Company recorded the related cost of goods sold of $21.1 million.

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