The Food and Drug Administration (FDA) has granted Fast Track designation to sisunatovir (RV521; ReViral) for the treatment of patients with serious respiratory syncytial virus (RSV) infection.

RSV is a common respiratory virus that generally results in mild, cold-like symptoms. However, for certain patients, particularly children and older adults, RSV infection can lead to significant complications such as bronchiolitis and pneumonia.

Sisunatovir is an orally administered RSV fusion inhibitor that binds to RSV-F protein on the viral surface inhibiting RSV replication. Findings from a phase 2a study showed that treatment with sisunatovir led to statistically significant reductions in viral load and clinical symptoms in healthy adult volunteers inoculated with RSV challenge virus (n=66). The treatment was also found to be well tolerated, with none of the study participants discontinuing due to adverse events. Moreover, the study authors reported that there was no evidence of clinically significant viral resistance.

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The Company recently initiated phase 2 studies (REVIRAL 1 and 2) evaluating sisunatovir in pediatric and adult high-risk patient populations.

“RSV affects approximately 64 million people and causes approximately 160,000 deaths each year,” said Alex Sapir, CEO, ReViral. “We look forward to working closely with the FDA throughout the clinical development of this program with the goal of bringing a potentially life-saving treatment to patients as quickly as possible.”

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1. ReViral announces FDA Fast Track designation granted to sisunatovir for the treatment of serious respiratory syncytial virus infection. Accessed August 4, 2020.