Summary of Significant Accounting Policies	3 Months Ended
Mar. 31, 2026
Accounting Policies [Abstract]
Summary of Significant Accounting Policies	Summary of Significant Accounting Policies Significant Accounting Policies The Company’s significant accounting policies are disclosed in the audited consolidated financial statements for the year ended December 31, 2025 and the notes thereto, which are included in the Company’s Annual Report on Form 10-K for the fiscal year ended December 31, 2025, filed with the U.S. Securities and Exchange Commission (“SEC”) on March 27, 2026 (the “Annual Report”), and there have been no material changes to such policies during the three months ended March 31, 2026. Basis of Presentation and Consolidation The condensed consolidated financial statements have been prepared in accordance with generally accepted accounting principles in the United States (“GAAP”) and include the Company’s accounts and those of its former wholly owned Australian subsidiary, Kezar Life Sciences Australia Pty Ltd., a proprietary company limited by shares, which was dissolved as of September 29, 2025. All intercompany balances and transactions have been eliminated upon consolidation. The condensed consolidated balance sheet as of December 31, 2025 has been derived from the audited consolidated financial statements at that date but does not include all information and footnotes required by GAAP for complete financial statements. These unaudited condensed consolidated financial statements should be read in conjunction with the audited financial statements included in the Annual Report. Unaudited Condensed Consolidated Financial Statements The accompanying financial information as of March 31, 2026 is unaudited. The condensed consolidated financial statements included in this report reflect all adjustments (consisting only of normal recurring adjustments) that our management considers necessary for the fair statement of the results of operations for the interim periods covered and of our financial condition at the date of the interim balance sheet. The accompanying unaudited condensed consolidated financial statements have been prepared in accordance with GAAP for interim financial information. Accordingly, they do not include all of the information and notes required by GAAP for complete financial statements. The results for interim periods are not necessarily indicative of the results for the entire year or any other interim period. The accompanying condensed consolidated financial statements and related financial information should be read in conjunction with the audited financial statements and the related notes thereto included in our Annual Report. Use of Estimates The preparation of financial statements in conformity with 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 the reported amounts of revenue and expenses during the reporting period. Significant items subject to such judgments, estimates and assumptions include the valuation of marketable securities, impairment of long-lived assets, determining the fair-value of stock-based compensation, and evaluating the progress to completion of external research and development costs. Management bases its estimates on historical experience and on various other market-specific relevant assumptions that management believes to be reasonable under the circumstances. Actual results may differ from those estimates. Estimates and assumptions about future events and their effects cannot be determined with certainty and therefore require the exercise of judgment. As of the date of issuance of these financial statements, the Company is not aware of any specific event or circumstance that would require the Company to update its judgments, estimates and assumptions or revise the carrying value of its assets or liabilities. These estimates may change as new events occur and additional information is obtained and are recognized in the consolidated financial statements as soon as they become known. Actual results could differ from those estimates and any such differences may be material to the Company’s condensed consolidated financial statements. Recently Issued Accounting Pronouncements In December 2025, the Financial Accounting Standards Board (“FASB”) issued Accounting Standards Update No. 2025-12 Codification Improvements (“ASU 2025-12”), which address thirty-three issues, representing amendments to Accounting Standard Codification topics that clarify, correct errors or make minor improvements. The amendments make the Codification easier to understand and apply. ASU 2025-12 is effective for the Company in its annual reporting for fiscal year 2027, and in interim periods beginning in fiscal year 2027. Early adoption and retrospective application are permitted on an issue-by-issue basis. The Company is currently evaluating the impact of the adoption of ASU 2025-12 on its financial statements. In December 2025, the FASB issued Accounting Standards Update No. 2025-11 Interim Reporting (Topic 270) – Narrow-Scope Improvements (“ASU 2025-11”), which clarifies the guidance in Topic 270 to improve the consistency of interim financial reporting. ASU 2025-11 provides a comprehensive list of required interim disclosures and introduces a disclosure principle requiring entities to disclose events since the end of the last annual reporting period that have a material impact on the entity. ASU 2025-11 is effective for the Company in its annual reporting for fiscal year 2028, and in interim periods beginning in fiscal year 2028. Early adoption and retrospective application are permitted. The Company is currently evaluating the impact of the adoption of ASU 2025-11 on its financial statements. In September 2025, the FASB issued Accounting Standards Update No. 2025-06 Intangibles – Goodwill and Other – Internal-Use Software (Subtopic 350-40) – Targeted Improvements to the Accounting for Internal-Use Software (“ASU 2025-06”) to clarify and modernize the accounting for costs related to internal-use software by removing all references to software development project stages and clarifying the threshold entities apply to begin capitalizing costs. ASU 2025-06 is effective for the Company in its annual reporting for fiscal year 2028 on a prospective basis. Early adoption and retrospective reporting are permitted. The Company is currently evaluating the impact of the adoption of ASU 2025-06 on its financial statements. In November 2024, the FASB issued Accounting Standards Update No. 2024-03 Income Statement– Reporting Comprehensive Income – Expense Disaggregation Disclosures (“ASU 2024-03”), which requires more detailed information about specified categories of expenses included in certain expense captions presented on the face of the income statement. ASU 2024-03 is effective for fiscal years beginning after December 15, 2026 and for interim periods within fiscal years beginning after December 15, 2027. Early adoption is permitted. The amendments may be applied either prospectively to financial statements issued for reporting periods after the effective date of this ASU or retrospectively to all prior periods presented in the financial statements. The Company is currently evaluating the impact of the adoption of ASU 2024-03 on its financial statements and related disclosures. There have been no other recent accounting pronouncements, changes in accounting pronouncements or recently adopted accounting guidance that are expected to have a material impact on the Company’s condensed consolidated financial statements upon adoption.

The Company’s significant accounting policies are disclosed in the audited consolidated financial statements for the year ended December 31, 2025 and the notes thereto, which are included in the Company’s Annual Report on Form 10-K for the fiscal year ended December 31, 2025, filed with the U.S. Securities and Exchange Commission (“SEC”) on March 27, 2026 (the “Annual Report”), and there have been no material changes to such policies during the three months ended March 31, 2026.

The condensed consolidated financial statements have been prepared in accordance with generally accepted accounting principles in the United States (“GAAP”) and include the Company’s accounts and those of its former wholly owned Australian subsidiary, Kezar Life Sciences Australia Pty Ltd., a proprietary company limited by shares, which was dissolved as of September 29, 2025. All intercompany balances and transactions have been eliminated upon consolidation.

The condensed consolidated balance sheet as of December 31, 2025 has been derived from the audited consolidated financial statements at that date but does not include all information and footnotes required by GAAP for complete financial statements. These unaudited condensed consolidated financial statements should be read in conjunction with the audited financial statements included in the Annual Report.

The accompanying financial information as of March 31, 2026 is unaudited. The condensed consolidated financial statements included in this report reflect all adjustments (consisting only of normal recurring adjustments) that our management considers necessary for the fair statement of the results of operations for the interim periods covered and of our financial condition at the date of the interim balance sheet. The accompanying unaudited condensed consolidated financial statements have been prepared in accordance with GAAP for interim financial information. Accordingly, they do not include all of the information and notes required by GAAP for complete financial statements. The results for interim periods are not necessarily indicative of the results for the entire year or any other interim period. The accompanying condensed consolidated financial statements and related financial information should be read in conjunction with the audited financial statements and the related notes thereto included in our Annual Report.

The preparation of financial statements in conformity with 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 the reported amounts of revenue and expenses during the reporting period. Significant items subject to such judgments, estimates and assumptions include the valuation of marketable securities, impairment of long-lived assets, determining the fair-value of stock-based compensation, and evaluating the progress to completion of external research and development costs. Management bases its estimates on historical experience and on various other market-specific relevant assumptions that management believes to be reasonable under the circumstances. Actual results may differ from those estimates.

Estimates and assumptions about future events and their effects cannot be determined with certainty and therefore require the exercise of judgment. As of the date of issuance of these financial statements, the Company is not aware of any specific event or circumstance that would require the Company to update its judgments, estimates and assumptions or revise the carrying value of its assets or liabilities. These estimates may change as new events occur and additional information is obtained and are recognized in the consolidated financial statements as soon as they become known. Actual results could differ from those estimates and any such differences may be material to the Company’s condensed consolidated financial statements.

In December 2025, the Financial Accounting Standards Board (“FASB”) issued Accounting Standards Update No. 2025-12 Codification Improvements (“ASU 2025-12”), which address thirty-three issues, representing amendments to Accounting Standard Codification topics that clarify, correct errors or make minor improvements. The amendments make

the Codification easier to understand and apply. ASU 2025-12 is effective for the Company in its annual reporting for fiscal year 2027, and in interim periods beginning in fiscal year 2027. Early adoption and retrospective application are permitted on an issue-by-issue basis. The Company is currently evaluating the impact of the adoption of ASU 2025-12 on its financial statements.

In December 2025, the FASB issued Accounting Standards Update No. 2025-11 Interim Reporting (Topic 270) – Narrow-Scope Improvements (“ASU 2025-11”), which clarifies the guidance in Topic 270 to improve the consistency of interim financial reporting. ASU 2025-11 provides a comprehensive list of required interim disclosures and introduces a disclosure principle requiring entities to disclose events since the end of the last annual reporting period that have a material impact on the entity. ASU 2025-11 is effective for the Company in its annual reporting for fiscal year 2028, and in interim periods beginning in fiscal year 2028. Early adoption and retrospective application are permitted. The Company is currently evaluating the impact of the adoption of ASU 2025-11 on its financial statements.

In September 2025, the FASB issued Accounting Standards Update No. 2025-06 Intangibles – Goodwill and Other – Internal-Use Software (Subtopic 350-40) – Targeted Improvements to the Accounting for Internal-Use Software (“ASU 2025-06”) to clarify and modernize the accounting for costs related to internal-use software by removing all references to software development project stages and clarifying the threshold entities apply to begin capitalizing costs. ASU 2025-06 is effective for the Company in its annual reporting for fiscal year 2028 on a prospective basis. Early adoption and retrospective reporting are permitted. The Company is currently evaluating the impact of the adoption of ASU 2025-06 on its financial statements.

In November 2024, the FASB issued Accounting Standards Update No. 2024-03 Income Statement– Reporting Comprehensive Income – Expense Disaggregation Disclosures (“ASU 2024-03”), which requires more detailed information about specified categories of expenses included in certain expense captions presented on the face of the income statement. ASU 2024-03 is effective for fiscal years beginning after December 15, 2026 and for interim periods within fiscal years beginning after December 15, 2027. Early adoption is permitted. The amendments may be applied either prospectively to financial statements issued for reporting periods after the effective date of this ASU or retrospectively to all prior periods presented in the financial statements. The Company is currently evaluating the impact of the adoption of ASU 2024-03 on its financial statements and related disclosures.