INNA-051 intranasal prophylaxis to prevent viral respiratory illness in healthy adults 18–45.

A Randomized, Double-Blind, Two-Part, Placebo-Controlled, Multicenter, Phase 2a Study to Evaluate Safety, Tolerability, and Efficacy of INNA-051 as Prophylaxis for Respiratory Tract Illness in Healthy Adults 18 to 45 Years of Age Who Are at Risk for Viral Respiratory Infections

This trial will test whether weekly self-administered INNA-051 nasal powder can prevent or reduce viral respiratory infections in generally healthy adults aged 18–45 who have higher exposure risk.

Quick facts

• Phase: Phase 2
• Study type: Interventional
• Enrollment: 1100 (estimated)
• Ages: 18 Years to 45 Years
• Sex: All
• Sponsor: ENA Respiratory Pty Ltd (Industry-sponsored)
• Locations: 5 sites (Baltimore, Maryland and 4 other locations)
• Trial ID: NCT07222670 on ClinicalTrials.gov

What this trial studies

This randomized, double-blind, placebo-controlled Phase 2a trial tests INNA-051, a TLR2/6 agonist given as a bilateral intranasal dry powder, as a seasonal prophylactic against symptomatic viral respiratory illness. Generally healthy adults aged 18–45 who are at increased risk of exposure are randomized to receive INNA-051 or placebo once weekly for 4 weeks (Part A) or 12 weeks (Part B) during the respiratory virus season. Part A primarily examines safety and tolerability in an outpatient setting while Part B measures safety, tolerability, and the effect on occurrence, severity, and duration of symptomatic respiratory illness. The multicenter trial uses self-administration, regular monitoring for adverse events, and surveillance for symptomatic infections.

Who should consider this trial

Good fit: Ideal participants are generally healthy adults aged 18–45 who are at increased risk of exposure (for example, crowded living or high-contact occupations) and who agree to the contraception requirements.

Not a fit: People with chronic respiratory diseases (such as asthma), diabetes, active viral infections (HBV, HCV, HIV), or other exclusionary conditions are unlikely to be eligible or to receive benefit from this intervention.

Why it matters

Potential benefit: If successful, INNA-051 could provide a simple, broadly acting intranasal protection that reduces the chance, severity, or duration of viral respiratory illnesses in at-risk adults.

How similar studies have performed: Preclinical studies and early-phase work with intranasal TLR agonists have shown promise in reducing viral replication and symptoms, but large-scale clinical proof of broad-spectrum human protection remains limited.

Eligibility criteria

Inclusion Criteria:

* In good general health and without clinically significant medical, psychiatric, chronic or intermittent health conditions.
* At risk for exposure to viral respiratory infection, for example, living in crowded housing, university housing, or military barracks, working in a childcare center or caring for a child aged 10 or less, healthcare workers, factory workers, taxi and bus drivers, grocery clerks, and educators or counselors who work in crowded environments or with multiple exposures with different people daily.
* Agree to use highly effective birth control.

Exclusion Criteria:

* Presence of Type I or Type II diabetes, asthma or other chronic respiratory condition.
* Active infections including Hepatitis B Virus, Hepatitis C Virus, or Human Immunodeficiency (HIV).
* Concurrent participation in another clinical trial involving investigational product or prior receipt of investigational product within 90 days or 5 half-lives of the product.
* Active clinical signs or symptoms of acute respiratory illness (runny nose, sore throat, fever, etc.).
* Received a vaccine against Respiratory Syncytial Virus (RSV) or COVID-19 within 180 days.
* Pregnant or lactating women.

Where this trial is running

Baltimore, Maryland and 4 other locations

• Center for Vaccine Development and Global Health (CVD) — Baltimore, Maryland, United States (Recruiting)
• Naval Medical Research Command (NMRC) — Bethesda, Maryland, United States (Recruiting)
• Accellacare of Raleigh — Raleigh, North Carolina, United States (Recruiting)
• Accellacare of Piedmont HealthCare — Statesville, North Carolina, United States (Recruiting)
• Accellacare - Wilmington — Wilmington, North Carolina, United States (Recruiting)

Study contacts

• Study coordinator: ENA Respiratory

Conditions Viral Respiratory Infection; Viral Respiratory Illnesses; Respiratory virus; Viral respiratory infection; Viral respiratory illness; Prophylaxis; Intranasal; Viral respiratory disease