Revelation Biosciences Inc. announced that the first patient has been enrolled and dosed in a Phase 1b clinical study to evaluate the potential utility of REVTx-99 for treating patients with allergic rhinitis and patients with chronic nasal congestion without polyps. The clinical study is being conducted in Australia. The Phase 1b, randomized, double-blind, placebo-controlled, crossover design study is expected to enroll approximately 28 participants.

The primary endpoint is to evaluate the effects of REVTx-99 versus placebo on safety and tolerability. Key secondary endpoints include allergy symptoms (Total Nasal Symptom Score) and peak nasal inspiratory flow elicited by nasal allergen challenge. The study will have two cohorts: one cohort will receive study drug before the nasal allergen challenge (the prophylactic cohort) and the second cohort will receive study drug after the nasal allergen challenge (the treatment cohort).

The company expects the topline data in the first half of 2022. REVTx-99 is a proprietary intranasal drop formulation in development for the prevention or treatment of respiratory viral infection and is broadly applicable to most infectious viruses including influenza A, influenza B, parainfluenza, rhinovirus, respiratory syncytial virus (RSV), SARS-CoV-2, and its variants. The active ingredient in REVTx-99 stimulates the nasal (mucosal) innate immune system via interaction with toll-like receptor 4 (TLR4) to produce protective cytokines including interferons and interferon-related proteins.

These protective cytokines work in concert to blunt the ability of an invading virus to proliferate and survive. Phase 1 data showed REVTx-99 to be well-tolerated and to significantly increase intranasal protective cytokines. In addition to viral infection, REVTx-99 is also being developed for management of allergic rhinitis symptoms and chronic nasal congestion without polyps.

REVTx-99 upregulates a protein which competes for the native eotaxin receptor, CCR3, preventing eotaxin from recruiting eosinophils, thereby reducing recruitment of Th2 cells, and attenuating the allergic response. Allergic rhinitis also called hay fever, is a very common disorder that affects millions of patients annually and the hallmark complaint of nasal obstruction significantly impacts the quality of life. It is an allergic reaction to tiny particles in the air called allergens.

Symptoms include sneezing, nasal congestion and irritation of the nose, throat, mouth and eyes. Some treatment options may include antihistamines, anti-inflammatory nasal sprays, anti-leukotrienes, and surgery. Allergic rhinitis can lead to complications in some cases: nasal polyps, sinusitis, and middle ear infections.

People with severe chronic nasal congestion sometimes need surgery.