Recruiting
Phase 2
Phase 3

Zelicapavir

Sponsor:

Enanta Pharmaceuticals, Inc

Code:

NCT07908381

Conditions

RSV

Eligibility Criteria

Sex: All

Age: 18+

Healthy Volunteers: Not accepted

Interventions

zelicapavir

Placebo

Study Details

Brief summary:

Zelicapavir is a novel orally administered non-fusion replication inhibitor of RSV that is being developed for the treatment of patients with RSV infection. This phase 2b/3 study will evaluate the efficacy and safety of zelicapavir compared with placebo in adults with RSV who are at high risk for severe disease. High-risk participants include those who are either ≥75 years of age or ≥18 years of age with COPD and/or CHF. Participants will be non-hospitalized adults who have up to 72 hours of respiratory tract infection symptoms and test positive for RSV.

Conditions

RSV

Study ID

NCT07908381

Start date

Oct 19, 2026

Status verified date

Oct, 2026

Completion date

Jul, 2029

Anticipated

Primary completion date

Jul, 2029

Anticipated

Eligibility Criteria

Eligibility Criteria

Sex: All

Age: 18+

Healthy Volunteers: Not accepted

Inclusion Criteria:

  • Age ≥75 years at the time of enrollment, or, age ≥18 at the time of enrollment and has at least one of the following conditions that predispose them to complications of RSV infection:

1. CHF
2. COPD
  • New onset or worsening of preexisting symptoms consistent with respiratory tract infection no more than 72 hours before administration of the first dose of study intervention: feeling feverish, headache, neck pain, fatigue, loss of appetite, interrupted sleep, body aches, sore throat, nasal congestion, cough, cough with phlegm, wheezing, or short of breath.
  • Reports at least 2 of the following symptoms, one of which must be reported by the participant as at least moderate in severity using the RiiQ™: cough, cough with phlegm, wheezing, or short of breath.
  • Tested positive for RSV infection defined as a positive nucleic acid amplification test (PCR or other) or rapid-antigen viral detection test performed on a nasal swab specimen collected no more than 72 hours before administration of the first dose of study intervention.
  • A woman of childbearing potential who is sexually active with a male must agree to use two effective methods of contraception from the date of Screening until 30 days after her last dose of study drug.
  • A male subject who has not had a vasectomy and is sexually active with a woman of childbearing potential must agree to use effective contraception from the date of Screening to 90 days after his last dose of study drug.

Exclusion Criteria:

  • Reported history of respiratory infection (other than RSV) within 7 days prior to signing the ICF.
  • Anticipated need for hospitalization within 24 hours of signing the ICF.
  • Receiving dialysis or have known severe renal impairment.
  • Reported history of chronic liver disease, including cirrhosis, autoimmune hepatitis, end stage liver disease, history of hepatocellular carcinoma, or decompensated liver failure.
  • Prior receipt of or waiting to receive a bone marrow, stem cell, or solid organ transplant. Currently taking, or has taken within 7 days prior to randomization, or is anticipated to receive during the study, systemic medications that are known to cause immunosuppression. Note: Chronic use of immunomodulators such as dupilumab and omalizumab is permitted.

Study Design

Enrollment

860 participants

Anticipated

Allocation

Randomized

Intervention Model

Parallel Assignment

Primary purpose

Treatment

Interventions and Outcome Measures

Arms

experimental: zelicapavir

Zelicapavir 800 mg, orally

placebo comparator: Placebo

Matching placebo, orally

Interventions

zelicapavir

Zelicapavir 800mg, once daily for 7 days

Placebo

Participants will take matching placebo, once daily for 7 days

Primary outcome measure

  • Time to complete resolution of all 13 RSV symptoms as assessed by the Respiratory Infection Intensity and Impact Questionnaire (RiiQ) symptom scale [ Time Frame: Day 1 through Day 21 ]

Central Contacts and Locations

Central contacts

Chris Harris, MD

617-607-0800charris@enanta.com

Locations

C&A Clinical Trials Corp

Recruiting

Cape Coral, Florida, United States, 33990

Continental Clinical Research, LLC

Recruiting

Miami, Florida, United States, 33144

PanAmerican Clinical Research

Recruiting

Bluffton, South Carolina, United States, 29910

PanAmerican Clinical Research - Brownville

Recruiting

Brownsville, Texas, United States, 78520

More Information

Sponsor

Enanta Pharmaceuticals, Inc

Last update posted

Nov 2, 2026

Last verified

Oct, 2026

Keywords

  • High Risk
  • Respiratory Syncytial Virus
  • EDP-938
  • COPD
  • CHF
  • Elderly

Trial information was received from ClinicalTrials.gov and was last updated on 2026-11-03. This information was provided to ClinicalTrials.gov by Enanta Pharmaceuticals, Inc on 2026-11-02. Recruitment status is synced daily from ClinicalTrials.gov and may not reflect the sponsor's current status. Confirm during your call.