New Antiviral for Hospitalized Adults with COVID-19 Launches NIH Study

The U.S. National Institutes of Health recently confirmed it had initiated a multi-site, late-stage clinical trial evaluating an investigational antiviral for the treatment of COVID-19.

The therapeutic, known as S-217622 or ensitrelvir fumaric acid, was discovered by Hokkaido University, Sapporo, Japan, and Shionogi & Co., Ltd. 

The antiviral reduced COVID-19 symptoms in people with mild-to-moderate COVID-19, regardless of risk factors or vaccination status, according to results shared by Shionogi from a Phase 3 clinical trial conducted in 2022.

S-217622 is the first agent to be evaluated in a global, adaptive clinical research protocol known as Strategies and Treatments for Respiratory Infections & Viral Emergencies (STRIVE).

S-217622 suppresses the SARS-CoV-2 coronavirus replication by inhibiting the function of a key virus protein known as 3CL protease.

In November 2022, the drug received emergency regulatory approval in Japan, where it is referred to by the brand name Xocova.

“We hope results from this trial can be applied to improve the standard of care for people with COVID-19, which still causes hundreds of deaths each day in the United States, as well as to strengthen our pandemic preparedness,” said NIAID Deputy Director for Clinical Research and Special Projects H. Clifford Lane, M.D., in a press release on February 15, 2023.

“The STRIVE protocol and clinical research infrastructure can be adapted to evaluate additional agents for COVID-19 and therapeutics for other respiratory pathogens.”

The ongoing ACTIV-2 SCORPIO-HR clinical trial, also funded by NIAID, is evaluating the S-217622 antiviral in the outpatient population.

In the U.S., several COVID-19 antivirals are approved, led by Paxlovid™, which is generally available at pharmacies.