In separate decisions, the agencies said they had concluded that sotrovimab is no longer indicated as it seems to be ineffective against the BA.2 strain of the coronavirus Omicron variant that now dominates infections across the country.

Commentators said the nationwide stop had been anticipated as the FDA had repeatedly restricted the drug’s use in the northeastern part US and increasingly in other regions – at the latest count in 22 states – as BA.2 became dominant. According to the CDC, the BA.2 subvariant now accounts for 72% of the COVID-19 cases sequenced by US health authorities.

The GSK-Vir treatment is the latest antibody medication to run aground on Covid mutations. Products made by Eli Lilly and Regeneron were sidelined by the FDA in January as the delta variant subsided and Omicron gained prevalence.

In response to news of the withdrawal, the UK drugs giant and the California-based biotech said they are preparing to submit new data to the FDA to support a higher dose of sotrovimab to treat BA.2. The companies are also proceeding with plans to file for a full FDA approval for the treatment in the second half of 2022.

GSK and Vir expect to produce around 2 million doses of sotrovimab before mid-2022 and additional doses in the second half of this year. Since September 2020, the US government has purchased almost $2 billion worth of sotrovimab courses, according to reports citing US federal agencies.

The partners also plan to begin two Phase 3 trials with the antibody treatment before the end of June, according to a Vir filing with the US Securities and Exchange Commission (SEC).  These would assess sotrovimab’s efficacy in preventing symptomatic Covid-19 in uninfected immunocompromised patients. Results of both trials are expected before the end of 2022.             

Author: Dede Williams, Freelance Journalist