In the phase 3 portion of an adaptive trial conducted in COVID-19 outpatients, a monoclonal antibody cocktail of casirivimab and imdevimab (REGEN-COV) led to a significant reduction in the risk of COVID-related hospitalizations and death due to any cause.

According to the randomized trial, the antibody combination also resulted in resolution of symptoms and decreased viral load quicker than placebo. Hospitalizations due to COVID-19 or death from any cause were noted in 1.3% patients (18 of 1355 patients) in the group that received 2400 mg infusions of the study drug, in comparison with 4.6% (62 of 1341 patients) in the placebo group, with a relative risk reduction of 71.3% (P < .001). The study is published in the New England Journal of Medicine… (Medscape)