KYNTRA BIO, INC.

To the Board of Directors and Stockholders of FibroGen, Inc.

Opinions on the Financial Statements and Internal Control over Financial Reporting

We have audited the accompanying consolidated balance sheets of FibroGen, Inc. and its subsidiaries (the "Company") as of December 31, 2024 and 2023, and the related consolidated statements of operations, of comprehensive loss, of changes in redeemable non-controlling interests and stockholders’ deficit and of cash flows for the years then ended, including the related notes and financial statement schedule listed in the accompanying index (collectively referred to as the "consolidated financial statements"). We also have audited the Company's internal control over financial reporting as of December 31, 2024, based on criteria established in Internal Control - Integrated Framework (2013) issued by the Committee of Sponsoring Organizations of the Treadway Commission (COSO).

In our opinion, the consolidated financial statements referred to above present fairly, in all material respects, the financial position of the Company as of December 31, 2024 and 2023, and the results of its operations and its cash flows for the years then ended in conformity with accounting principles generally accepted in the United States of America. Also in our opinion, the Company maintained, in all material respects, effective internal control over financial reporting as of December 31, 2024, based on criteria established in Internal Control - Integrated Framework (2013) issued by the COSO.

Substantial Doubt About the Company's Ability to Continue as a Going Concern

The accompanying consolidated financial statements have been prepared assuming that the Company will continue as a going concern. As discussed in Note 2 to the consolidated financial statements, the Company needs to complete the sale of FibroGen International, access additional cash from its China operations, or raise additional capital in order to fund its United States operations and to comply with certain debt covenants under its senior secured short term loan facilities. These conditions raise substantial doubt about its ability to continue as a going concern. Management's plans in regard to these matters are also described in Note 2. The consolidated financial statements do not include any adjustments that might result from the outcome of this uncertainty.

Basis for Opinions

The Company's management is responsible for these consolidated financial statements, for maintaining effective internal control over financial reporting, and for its assessment of the effectiveness of internal control over financial reporting, included in Management’s Annual Report on Internal Control over Financial Reporting appearing under Item 9A. Our responsibility is to express opinions on the Company’s consolidated financial statements and on the Company's internal control over financial reporting based on our audits. We are a public accounting firm registered with the Public Company Accounting Oversight Board (United States) (PCAOB) and are required to be independent with respect to the Company in accordance with the U.S. federal securities laws and the applicable rules and regulations of the Securities and Exchange Commission and the PCAOB.

We conducted our audits in accordance with the standards of the PCAOB. Those standards require that we plan and perform the audits to obtain reasonable assurance about whether the consolidated financial statements are free of material misstatement, whether due to error or fraud, and whether effective internal control over financial reporting was maintained in all material respects.

Our audits of the consolidated financial statements included performing procedures to assess the risks of material misstatement of the consolidated financial statements, whether due to error or fraud, and performing procedures that respond to those risks. Such procedures included examining, on a test basis, evidence regarding the amounts and disclosures in the consolidated financial statements. Our audits also included evaluating the accounting principles used and significant estimates made by management, as well as evaluating the overall presentation of the consolidated financial statements. Our audit of internal control over financial reporting included obtaining an understanding of internal control over financial reporting, assessing the risk that a material weakness exists, and testing and evaluating the design and operating effectiveness of internal control based on the assessed risk. Our audits also included performing such other procedures as we considered necessary in the circumstances. We believe that our audits provide a reasonable basis for our opinions.

Definition and Limitations of Internal Control over Financial Reporting

A company’s internal control over financial reporting is a process designed to provide reasonable assurance regarding the reliability of financial reporting and the preparation of financial statements for external purposes in accordance with generally accepted accounting principles. A company’s internal control over financial reporting includes those policies and procedures that (i) pertain to the maintenance of records that, in reasonable detail, accurately and fairly reflect the transactions and dispositions of the assets of the company; (ii) provide reasonable assurance that transactions are recorded as necessary to permit preparation of financial statements in accordance with generally accepted accounting principles, and that receipts and expenditures of the company are being made only in accordance with authorizations of management and directors of the company; and (iii) provide reasonable assurance regarding prevention or timely detection of unauthorized acquisition, use, or disposition of the company’s assets that could have a material effect on the financial statements.

Because of its inherent limitations, internal control over financial reporting may not prevent or detect misstatements. Also, projections of any evaluation of effectiveness 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.

Critical Audit Matters

The critical audit matter communicated below is a matter arising from the current period audit of the consolidated financial statements that was communicated or required to be communicated to the audit committee and that (i) relates to accounts or disclosures that are material to the consolidated financial statements and (ii) involved our especially challenging, subjective, or complex judgments. The communication of critical audit matters does not alter in any way our opinion on the consolidated financial statements, taken as a whole, and we are not, by communicating the critical audit matter below, providing a separate opinion on the critical audit matter or on the accounts or disclosures to which it relates.

Determining the Transaction Price for Product Revenue Recognition for Sales to Beijing Falikang Pharmaceutical Co. Ltd. ("Falikang")

As described in Notes 2, 3, and 4 to the consolidated financial statements, with respect to the roxadustat commercial product, revenue is recognized at a point in time when control of the product is transferred to Falikang. Total product revenue, net recognized related to sales to Falikang was $159.0 million for the year ended December 31, 2024. Revenue is recognized based on the estimated transaction price per unit and the actual quantity of product delivered to Falikang during the reporting period. The estimated transaction price per unit is determined based on the overall transaction price over the total estimated sales quantity for the estimated performance period in which management determined it is likely those sales would occur. Management applied significant judgment in determining the transaction price per unit, which involved the use of significant assumptions such as (i) the estimated total gross transaction price and profit share, (ii) the estimated total sales quantity, and (iii) the estimated performance period in which the Company determined it is likely those sales would occur.

The principal considerations for our determination that performing procedures relating to determining the transaction price for product revenue recognition for sales to Falikang is a critical audit matter are the significant judgment by management when determining the transaction price per unit, which in turn led to a high degree of auditor judgment, subjectivity, and effort in performing procedures and in evaluating management’s significant assumptions related to the estimated total gross transaction price, estimated total sales quantity, and estimated performance period over which the Company determined it is likely those sales would occur.

Addressing the matter involved performing procedures and evaluating audit evidence in connection with forming our overall opinion on the consolidated financial statements. These procedures included testing the effectiveness of controls relating to revenue recognition, including controls over the determination of the transaction price per unit for sales to Falikang. These procedures also included, among others, testing management’s process for determining the transaction price per unit, which included evaluating the appropriateness of the method, testing the completeness and accuracy of the data used in the method, and evaluating the reasonableness of significant assumptions related to the estimated total gross transaction price, estimated total sales quantity, and estimated performance period over which the Company determined it is likely those sales would occur. Evaluating the reasonableness of the significant assumptions used by management involved evaluating whether the assumptions were reasonable considering (i) the current and historical transaction price and quantity, (ii) the consistency with external market, industry and regulatory data, (iii) whether these assumptions were consistent with evidence obtained in other areas of the audit, and (iv) patent expiration and market exclusivity.

/s/PricewaterhouseCoopers LLP

Irvine, California

March 17, 2025

We have served as the Company’s auditor since 2000.