Nature of the Business and Basis of Presentation	3 Months Ended
Dec. 31, 2025
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Nature of the Business and Basis of Presentation	1. Nature of the Business and Basis of Presentation Enanta Pharmaceuticals, Inc. (collectively with its subsidiary, the “Company”), incorporated in Delaware in 1995, is a biotechnology company that uses its robust, chemistry-driven approach and drug discovery capabilities to discover and develop small molecule drugs for virology and immunology indications. The Company discovered glecaprevir, the second of two antiviral protease inhibitors developed through its collaboration with AbbVie for the treatment of acute or chronic infection with hepatitis C virus, or HCV. Glecaprevir is co-formulated as part of AbbVie’s leading brand of direct-acting antiviral, or DAA, combination treatment for HCV, which has been marketed under the tradenames MAVYRET® (U.S.) and MAVIRET® (ex-U.S.) (glecaprevir/pibrentasvir) since 2017. The Company is subject to many of the risks common to companies in the biotechnology industry, including but not limited to, the uncertainties of research and development, competition from technological innovations of others, dependence on collaborative arrangements, protection of proprietary technology, dependence on key personnel and compliance with government regulation. Product candidates currently under development will require significant additional research and development efforts, including extensive preclinical and clinical testing and regulatory approvals, prior to commercialization. These efforts require significant amounts of capital, adequate personnel and infrastructure, and extensive compliance reporting capabilities. Unaudited Interim Financial Information The condensed consolidated balance sheet as of September 30, 2025 was derived from audited financial statements but does not include all disclosures required by accounting principles generally accepted in the United States of America (“GAAP”). The accompanying unaudited condensed consolidated financial statements as of December 31, 2025 and for the three months ended December 31, 2025 and 2024 have been prepared by the Company pursuant to the rules and regulations of the Securities and Exchange Commission (“SEC”) for interim financial statements. Certain information and footnote disclosures normally included in financial statements prepared in accordance with GAAP have been condensed or omitted pursuant to such rules and regulations. These condensed consolidated financial statements should be read in conjunction with the Company’s audited consolidated financial statements and the notes thereto included in the Company’s Annual Report on Form 10-K for the fiscal year ended September 30, 2025. In the opinion of management, all adjustments, consisting of normal recurring adjustments necessary for a fair statement of the Company’s financial position as of December 31, 2025 and results of operations for the three months ended December 31, 2025 and 2024 and cash flows for the three months ended December 31, 2025 and 2024 have been made. The results of operations for the three months ended December 31, 2025 are not necessarily indicative of the results of operations that may be expected for subsequent quarters or the year ending September 30, 2026. The accompanying condensed consolidated financial statements have been prepared in conformity with GAAP. All amounts in the condensed consolidated financial statements and in the notes to the condensed consolidated financial statements, except per share amounts, are in thousands unless otherwise indicated. The accompanying condensed consolidated financial statements have been prepared based on continuity of operations, realization of assets and the satisfaction of liabilities and commitments in the ordinary course of business. The Company began reporting a net loss in fiscal 2020 and reported a net loss of $11,938 for the three months ended December 31, 2025 and $81,889 for the year ended September 30, 2025. As of December 31, 2025, the Company had an accumulated deficit of $416,867. The Company expects to continue to generate operating losses for the foreseeable future as the Company continues to advance its wholly-owned programs. As of December 31, 2025, the Company had $241,904 in cash, cash equivalents and short-term and long-term marketable securities. The Company expects that its cash, cash equivalents and short-term and long-term marketable securities will be sufficient to fund its operating expenses and capital expenditure requirements for at least 12 months from the issuance date of the interim condensed consolidated financial statements. The Company may seek additional funding through equity offerings, non-dilutive financings, collaborations, strategic alliances or licensing agreements. The Company may not be able to obtain sufficient financing on acceptable terms, or at all, and the Company may not be able to enter into collaborations or other arrangements. The terms of any financing may adversely affect the holdings or the rights of the Company’s stockholders. If the Company is unable to obtain funding, the Company could be forced to delay, reduce or eliminate some or all of its research and development programs, product expansion or commercialization efforts, or the Company may be unable to continue operations. Follow-on Public Offering In October 2025, the Company closed an underwritten public offering of its common stock. The Company issued and sold 7,475 shares of its common stock at a public offering price of $10.00 per share. The aggregate gross proceeds of the offering, before deducting underwriting discounts and commissions and other offering expenses, were $74,750.

Nature of the Business and Basis of Presentation

3 Months Ended

Dec. 31, 2025

Organization, Consolidation and Presentation of Financial Statements [Abstract]

Nature of the Business and Basis of Presentation

1. Nature of the Business and Basis of Presentation

Enanta Pharmaceuticals, Inc. (collectively with its subsidiary, the “Company”), incorporated in Delaware in 1995, is a biotechnology company that uses its robust, chemistry-driven approach and drug discovery capabilities to discover and develop small molecule drugs for virology and immunology indications. The Company discovered glecaprevir, the second of two antiviral protease inhibitors developed through its collaboration with AbbVie for the treatment of acute or chronic infection with hepatitis C virus, or HCV. Glecaprevir is co-formulated as part of AbbVie’s leading brand of direct-acting antiviral, or DAA, combination treatment for HCV, which has been marketed under the tradenames MAVYRET® (U.S.) and MAVIRET® (ex-U.S.) (glecaprevir/pibrentasvir) since 2017.

The Company is subject to many of the risks common to companies in the biotechnology industry, including but not limited to, the uncertainties of research and development, competition from technological innovations of others, dependence on collaborative arrangements, protection of proprietary technology, dependence on key personnel and compliance with government regulation. Product candidates currently under development will require significant additional research and development efforts, including extensive preclinical and clinical testing and regulatory approvals, prior to commercialization. These efforts require significant amounts of capital, adequate personnel and infrastructure, and extensive compliance reporting capabilities.

Unaudited Interim Financial Information

The condensed consolidated balance sheet as of September 30, 2025 was derived from audited financial statements but does not include all disclosures required by accounting principles generally accepted in the United States of America (“GAAP”). The accompanying unaudited condensed consolidated financial statements as of December 31, 2025 and for the three months ended December 31, 2025 and 2024 have been prepared by the Company pursuant to the rules and regulations of the Securities and Exchange Commission (“SEC”) for interim financial statements. Certain information and footnote disclosures normally included in financial statements prepared in accordance with GAAP have been condensed or omitted pursuant to such rules and regulations. These condensed consolidated financial statements should be read in conjunction with the Company’s audited consolidated financial statements and the notes thereto included in the Company’s Annual Report on Form 10-K for the fiscal year ended September 30, 2025.

In the opinion of management, all adjustments, consisting of normal recurring adjustments necessary for a fair statement of the Company’s financial position as of December 31, 2025 and results of operations for the three months ended December 31, 2025 and 2024 and cash flows for the three months ended December 31, 2025 and 2024 have been made. The results of operations for the three months ended December 31, 2025 are not necessarily indicative of the results of operations that may be expected for subsequent quarters or the year ending September 30, 2026.

The accompanying condensed consolidated financial statements have been prepared in conformity with GAAP. All amounts in the condensed consolidated financial statements and in the notes to the condensed consolidated financial statements, except per share amounts, are in thousands unless otherwise indicated.

The accompanying condensed consolidated financial statements have been prepared based on continuity of operations, realization of assets and the satisfaction of liabilities and commitments in the ordinary course of business. The Company began reporting a net loss in fiscal 2020 and reported a net loss of $11,938 for the three months ended December 31, 2025 and $81,889 for the year ended September 30, 2025. As of December 31, 2025, the Company had an accumulated deficit of $416,867. The Company expects to continue to generate operating losses for the foreseeable future as the Company continues to advance its wholly-owned programs. As of December 31, 2025, the Company had $241,904 in cash, cash equivalents and short-term and long-term marketable securities. The Company expects that its cash, cash equivalents and short-term and long-term marketable securities will be sufficient to fund its operating expenses and capital expenditure requirements for at least 12 months from the issuance date of the interim condensed consolidated financial statements. The Company may seek additional funding through equity offerings, non-dilutive financings, collaborations, strategic alliances or licensing agreements. The Company may not be able to obtain sufficient financing on acceptable terms, or at all, and the Company may not be able to enter into collaborations or other arrangements. The terms of any financing may adversely affect the holdings or the rights of the Company’s stockholders. If the Company is unable to obtain funding, the Company could be forced to delay, reduce or eliminate some or all of its research and development programs, product expansion or commercialization efforts, or the Company may be unable to continue operations.

Follow-on Public Offering

In October 2025, the Company closed an underwritten public offering of its common stock. The Company issued and sold 7,475 shares of its common stock at a public offering price of $10.00 per share. The aggregate gross proceeds of the offering, before deducting underwriting discounts and commissions and other offering expenses, were $74,750.