The U.S. Food and Drug Administration (FDA) has rescinded the emergency use authorization (EUA) for sotrovimab, a COVID-19 treatment developed by GlaxoSmithKline (GSK) and Vir Biotechnology. This decision, announced on Tuesday, comes in response to the drug's diminished effectiveness against the now-dominant Omicron sub-variant BA.2.
Sotrovimab initially gained EUA in May 2021 for treating mild to moderate COVID-19 in high-risk adults and pediatric patients. The authorization was based on a Phase III clinical trial that demonstrated an 85% reduction in the risk of hospitalization or death. At the time, in vitro data suggested the drug was effective against all known variants of concern.
The U.S. government invested heavily in sotrovimab, signing a $1 billion contract for doses in November 2021 and purchasing an additional 600,000 doses in January 2022 to enhance nationwide access. However, as the Omicron BA.2 subvariant surged in early 2022, concerns arose regarding sotrovimab's efficacy. Data from Columbia University and researchers in Japan indicated that sotrovimab was not effective at neutralizing BA.2.
In late February, the FDA initially limited sotrovimab's use to regions where BA.2 was not prevalent. This limitation was further updated in late March, excluding several states and territories. Finally, on April 5, the FDA completely revoked the therapeutic's authorization across all U.S. regions.
GSK and Vir maintain that sotrovimab remains effective against BA.2, despite the scientific community's concerns. In response to the FDA's initial limitations, the companies planned to submit data supporting the use of a higher dose of the drug for the Omicron BA.2 sub-variant to the Securities and Exchange Commission. Furthermore, they intend to apply for full approval of sotrovimab in the second half of 2022 and initiate late-stage clinical trials to evaluate its potential in preventing symptomatic COVID-19 infection in immunocompromised patients.
Currently, few approved or authorized treatments for COVID-19 demonstrate efficacy against BA.2. Eli Lilly's bebtelovimab received EUA in February based on data supporting its efficacy against BA.2.
