Revelation Biosciences Inc. outlined details on the upcoming data analysis for Phase 2b viral challenge study (RVL-VRL01) to evaluate the efficacy of intranasal REVTx-99a for the preventive treatment of H3N2 influenza (influenza A) infection in healthy humans. Dosing and enrollment for this study were recently completed and primary endpoint analysis is expected early Second Quarter 2022, followed by final data analysis in Second Quarter 2022. The Phase 2b, randomized, double-blind, placebo-controlled study was conducted in Belgium and enrolled healthy individuals 18 to 55 years of age.

The primary endpoint is to evaluate the efficacy of REVTx-99a in reducing area under the curve (AUC) influenza viral load in the upper airways during infection as measured by RT-qPCR relative to placebo. The results will inform if REVTx-99a is better, just as good, or worse than placebo at controlling the amount of influenza virus in a person's body. Generally, the higher the amount of virus (viral load), the more infected, and by conjunction, the sicker a person may be.

Reducing viral load is an indicator of clinical benefit and likely to correlate with reduced symptoms. 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. REVTx-99a activates a nonspecific immune response (a targeted, local innate response) which differentiates it from most current treatments focused on a specific immune response (an adaptive response), potentially enabling the use of REVTx-99a for broader use across most infectious upper respiratory viruses. The viral challenge study is the next necessary step in clinical development of REVTx-99a 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.