Revelation Biosciences Inc. announced that the first group of 15 patients have been enrolled and dosed in a Phase 2b viral challenge study (RVL-VRL01) to evaluate the efficacy of intranasal REVTx-99 for the preventive treatment of H3N2 influenza (influenza A) infection in healthy humans. The study is being conducted in Belgium and is enrolling healthy individuals 18 to 55 years of age. REVTx-99 activates a nonspecific immune response (innate) which differentiates it from most current treatments focused on a specific immune response (adaptive) potentially allowing for broader use in most infectious viruses.

The viral challenge study is the next necessary step in clinical development of REVTx-99 for the treatment of respiratory viral infections. Future development plans include clinical studies in SARS-CoV-2 and its variants, along with other respiratory viruses. The Phase 2b, randomized, double-blind, placebo-controlled study will enroll up to 60 participants (four groups of 15 patients).

The primary endpoint is to evaluate the efficacy of REVTx-99 in reducing area under the curve (AUC) influenza viral load in the upper airways during infection. Key secondary endpoints include: AUC of total symptom score, duration of symptoms, peak symptom score, peak viral load, duration of influenza virus presence, incidence of mild to moderate influenza disease (MMID) and incidence of seroconversion. The study will have multiple and single dose randomized cohorts.

Efficacy of the interventional strategies shall be assessed by measuring the incidence and severity of the disease in the active treatment groups compared to the placebo group along with parameters of safety associated with adverse events and airway physiology.