In April 2020, Lawrence Berkeley National Laboratory conducted a X-ray crystallography study at Virs request to investigate how such antibodies bind to SARS-CoV-2 at the molecular level. The Berkeley Lab data helped Vir identify candidates for further study, and Vir eventually settled on a single candidate antibody, S309. Vir collaborated with GlaxoSmithKline to make various refinements to S309, resulting in sotrovimab.Sotrovimab has been engineered to possess an Fc LS mutation (M428L/N434S) that confers enhanced binding to the neonatal Fc receptor resulting in an extended half-life and potentially enhanced drug distribution to the lungs.Sotrovimab has demonstrated activity via two antiviral mechanisms in vitro, antibody-dependent cellular cytotoxicity (ADCC) and antibody-dependent cellular phagocytosis (ADCP). Clinical efficacy
The pivotal COMET-ICE study is an ongoing, randomized, double-blind, placebo-controlled study to assess the safety and efficacy of sotrovimab in adults with confirmed COVID-19 (mild, early disease with less than five days of symptoms) at risk of disease progression.An interim analysis of this study reported that sotrovimab reduced the risk of hospitalization for more than 24 hours or death by 85% compared with placebo. Overall 1% of people receiving sotrovimab died or required hospitalization for more than 24 hours compared to 7% of people treated with placebo.
The study is ongoing and preliminary results have been published in the New England Journal of Medicine.The full analysis of the COMET-ICE trial was published in JAMA and it showed that sotrovimab reduced risk of hospitalization for more than 24 hours or death by 79% compared to placebo (1% for sotrovoimab group and 6% for the placebo group). The trial involved 1057 participants and took place before the omicron variant was prevalent. Manufacturing
Sotrovimab is a biologic product which takes six months to manufacture in living cells. It is produced in Chinese hamster ovary cells. At product launch in May 2021, sotrovimabs active pharmaceutical ingredient was produced by WuXi Biologics in China and sent to a GlaxoSmithKline plant in Parma, Italy for further processing into the finished product. In January 2022, the spread of the SARS-CoV-2 Omicron variant began to render other monoclonal antibodies obsolete and caused global demand for sotrovimab to skyrocket. In response, Vir and GlaxoSmithKline announced they were working with Samsung Biologics on manufacturing sotrovimab at an additional site in South Korea. Society and culture
Economics
In 2021, the United States government agreed to purchase 1.5 million doses of the drug at $2,100 per dose. Legal status
In May 2021, the Committee for Medicinal Products for Human Use (CHMP) of the European Medicines Agency (EMA) completed its review on the use of sotrovimab for the treatment of COVID-19.