| Item 7.01 |
Regulation FD Disclosure. |
On September 29, 2025, Enanta Pharmaceuticals, Inc. (“Enanta”) issued a press release announcing positive topline data from its Phase 2b high-risk adults study of zelicapavir (formerly EDP-938) for the treatment of respiratory syncytial virus (“RSV”). A copy of the press release is furnished as Exhibit 99.1 hereto and is incorporated herein by this reference.
The information in Item 7.01 of this Current Report on Form 8-K, including Exhibit 99.1 attached hereto, is intended to be furnished and shall not be deemed “filed” for purposes of Section 18 of the Securities and Exchange Act of 1934, as amended (the “Exchange Act”), or otherwise subject to the liabilities of that section, nor shall it be deemed incorporated by reference in any filing under the Securities Act of 1933, as amended, or the Exchange Act, except as expressly set forth by specific reference in any such filing.
As noted in Item 7.01 above, Enanta announced positive topline data from its Phase 2b high-risk adults study of zelicapavir for the treatment of RSV on September 29, 2025.
This Phase 2b study was a randomized, double-blind, placebo-controlled study of RSV infection in non-hospitalized adults who are at high risk of complications, including the elderly and/or those with congestive heart failure (“CHF”), chronic obstructive pulmonary disease (“COPD”) or asthma. The proportion of patients aged 65-74 years or those with asthma was capped at 20% of the total population. Patients were enrolled within 72 hours of symptom onset and received 800mg of zelicapavir or placebo once daily for 5 days. The goal of this proof-of-concept, signal finding study was to inform the design of a Phase 3 trial, including populations and endpoints, as well as give an indication of a treatment effect on symptoms that could be confirmed in a larger registrational study. Symptoms were measured using the Respiratory Infection Intensity and Impact Questionnaire (“RiiQTM”) scale, which evaluates a total of 29 parameters, including 13 RSV symptoms, four of which are lower respiratory tract disease (“LRTD”) symptoms, and three other impact of disease components (daily activities, emotions, and social relationships). The primary endpoint evaluated the time to resolution of the LRTD subset of four symptoms to mild. Predefined analyses of complete resolution, defined by all symptoms absent, were also conducted. Multiple secondary endpoints, including all 13 RSV symptoms, total RiiQTM score, additional patient reported outcomes (e.g.; PGI-S), virology, safety, and hospitalization rate, were assessed.
A total of 186 subjects received 800mg of zelicapavir (n=121) or placebo (n=65) orally, once daily for 5 days and were evaluated for 28 days thereafter (safety population). An efficacy population of 175 patients was further defined as those who were PCR positive for RSV at a central laboratory. An HR3 population was defined as those who had CHF, COPD, or age >75 (81% of the efficacy population). Demographics and baseline characteristics were balanced across treatment groups, with the majority of patients being enrolled within 48 hours of symptom onset.
Zelicapavir demonstrated a favorable safety profile over the initial 5-day dosing period and through 28 days of follow-up, with adverse events (“AEs”) being similar between zelicapavir and placebo. No adverse events led to treatment discontinuation or study withdrawal in the zelicapavir group. The majority of AEs were mild with diarrhea and asthma being the most common AEs on zelicapavir at 3.3% and 2.5%, respectively.
