Welcome to our dedicated page for ENANTA PHARMACEUTICALS SEC filings (Ticker: ENTA), a comprehensive resource for investors and traders seeking official regulatory documents including 10-K annual reports, 10-Q quarterly earnings, 8-K material events, and insider trading forms.
Enanta Pharmaceuticals, Inc. filings document a clinical-stage biotechnology issuer focused on small-molecule therapies for viral infections and immunological diseases. Its Form 8-K disclosures cover financial results, Regulation FD clinical-data materials, research and development updates, material agreements and capital-structure information for common stock traded under ENTA on the Nasdaq Global Select Market.
Proxy and annual meeting filings record governance matters including director elections, advisory executive compensation votes, auditor ratification and amendments to the 2019 Equity Incentive Plan. Other event disclosures also document patent litigation matters, including proceedings involving U.S. Patent No. 11,358,953 and Pfizer's COVID-19 antiviral Paxlovid.
Enanta Pharmaceuticals (ENTA) prospectus supplement excerpts describe an offering with underwriter arrangements, lock-up agreements and planned use of proceeds to fund clinical trials, research and general corporate purposes. The company notes ongoing royalties from an AbbVie collaboration and proceeds from an April 2023 royalty sale that support its R&D programs.
The filing highlights clinical and preclinical programs including a STAT6 oral inhibitor program with a development candidate expected to be nominated in the second half of 2025, zelicapavir safety outcomes (mostly mild AEs; diarrhea 3.3%, asthma 2.5%) and antiviral efficacy signals versus placebo. The supplement also summarizes U.S. federal tax withholding rules for non-U.S. holders and customary risk and forward-looking statement disclaimers.
Enanta Pharmaceuticals reported that it has positive topline results from a Phase 2b study of its drug candidate zelicapavir (formerly EDP-938) in high-risk adults with respiratory syncytial virus (RSV). This mid-stage trial focuses on adults who are more likely to develop serious RSV disease, so encouraging data at this stage can be important for deciding whether to move the program into later-stage studies.
To share more detail, the company prepared a slide deck titled “Phase 2b Study of Zelicapavir in High-Risk Adults: RSVHR Topline Results,” which is included as an exhibit to this report. The presentation is being furnished rather than filed, which limits how it is treated under certain securities law liability provisions, but it provides investors with an overview of the initial clinical findings for zelicapavir in RSV.
Enanta Pharmaceuticals filed an Form 8-K reporting a proof-of-concept, signal-finding study of oral antiviral zelicapavir for RSV. Patients were enrolled within 72 hours of symptom onset and received 800mg once daily for 5 days or placebo. The trial measured symptoms using the RiiQTM scale covering 13 RSV symptoms and assessed a four-symptom lower respiratory tract disease (LRTD) subset as the primary endpoint, defined as time to resolution to mild, with predefined complete-resolution analyses also conducted. Secondary measures included total RiiQTM score, patient global impressions, virology, safety, and hospitalization rate. The filing references the company’s 2024 10-K and includes the company caution on forward-looking statements. The 8-K is signed by Jay R. Luly, Ph.D. and dated September 29, 2025.
Enanta Pharmaceuticals (ENTA) Form 3: Kathleen S. Capps reports beneficial ownership tied to her role as Executive Director, Accounting & Controller and director/officer of Enanta. She directly holds 5,829 shares represented by unvested RSUs and a series of stock options exercisable between 04/01/2026 and 11/27/2034 covering named share amounts. The filing lists vesting schedules for RSUs and exercise prices for each option.
Enanta Pharmaceuticals (ENTA) Form 3: Harry R. Trout III reported ownership of 10,912 shares of Enanta common stock, consisting of 762 vested shares and 10,150 shares underlying unvested restricted stock units (RSUs). The RSUs vest in scheduled installments between December 1, 2025 and subsequent annual or multi-year installment schedules described in the filing. Mr. Trout also holds a series of stock options covering 53,966 underlying shares with exercise prices ranging from $8.83 to $81.20; one option grant is 100% vested and exercisable and other grants vest quarterly over four years from their grant dates. The filing was signed by an attorney-in-fact on Mr. Trout's behalf.
Enanta Pharmaceuticals reported temporary changes in its finance leadership. On August 26, 2025, the board named Harry R. Trout, III, the company’s Vice President of Finance, as interim principal financial officer and Kathleen (“Katie”) S. Capps, CPA, Executive Director, Accounting & Controller, as interim principal accounting officer. These appointments are explicitly described as interim while Chief Financial and Administrative Officer Paul J. Mellett is on a medical leave of absence and will continue until he is able to resume his roles. The company notes that Trout and Capps have long tenures in accounting and finance roles, will be eligible for standard indemnification agreements, and have not entered into any new material compensation or other arrangements in connection with these interim appointments. The filing also states there are no family relationships or related-party transactions involving either executive that require disclosure.
Enanta Pharmaceuticals, Inc. filed a current report describing new patent litigation related to COVID-19 treatments. On August 20, 2025, Enanta announced it filed a suit in the Unified Patent Court of the European Union against Pfizer Inc. and certain subsidiaries.
The action seeks a determination of liability for alleged use and infringement of European Patent No. EP 4 051 265 in connection with the manufacture, use and sale of Pfizer’s COVID-19 antiviral Paxlovid (nirmatrelvir tablets; ritonavir tablets) across 18 participating EU countries. The patent, granted and published on August 20, 2025, stems from Enanta’s July 2020 coronavirus protease inhibitor work and is the European counterpart to a U.S. patent already in related U.S. litigation between the companies.
Enanta Pharmaceuticals reported stable royalty-driven revenue but continued operating losses while advancing multiple clinical and preclinical programs. Royalty revenue was $18.3 million for the quarter and $50.2 million for the nine months ended June 30, 2025. The company posted a net loss of $18.3 million for the quarter and $63.2 million for the nine months, and had an accumulated deficit of $386.2 million as of June 30, 2025.
Enanta held $204.1 million in cash, cash equivalents and short-term marketable securities and stated that these resources, together with retained royalty cash flows, are expected to fund operations into fiscal 2028. The company recorded a $147.7 million liability related to a $200.0 million royalty sale transaction and continues to recognize 100% of HCV royalties as revenue. Clinical updates include positive pediatric topline results for zelicapavir, completion of enrollment in a Phase 2b high-risk adult zelicapavir study (topline expected September 2025), positive Phase 2a challenge results for EDP-323, Phase 2 results for EDP-235, and progression of immunology programs (KIT and STAT6). The company has appealed a district court decision invalidating a patent asserted against Pfizer; appeal briefs have been filed.
Enanta Pharmaceuticals, Inc. filed a Form 8-K to report that it has announced its financial results for the fiscal quarter ended June 30, 2025. On August 11, 2025, the company issued a press release with these quarterly results and furnished that release as Exhibit 99.1. The filing is primarily administrative, directing readers to the press release for detailed financial information, and is signed on behalf of the company by President and Chief Executive Officer Jay R. Luly, Ph.D.
Scott T. Rottinghaus, identified in this filing as Chief Medical Officer of Enanta Pharmaceuticals (ENTA), reported a non-sale equity transaction dated 08/08/2025 in which 2,217 shares of ENTA common stock were forfeited to satisfy withholding taxes arising from the settlement of a portion of a restricted stock unit award granted on August 8, 2022. The filing lists a per-share amount of $6.99 associated with the transaction. Following the withholding forfeiture, the reporting person beneficially owns 22,590 shares of common stock directly. The Form 4 entry indicates this was an internal tax-withholding action rather than an open-market disposition and was executed by an attorney-in-fact on behalf of the reporting person.