Background: Coronavirus disease 2019 disproportionately results in hospitalization and death in older patients and those with underlying comorbidities. Sotrovimab is a pansarbecovirus monoclonal antibody designed to treat such high-risk patients early in the course of disease, thereby preventing Covid-19 progression. Methods:In this ongoing, multicenter, double-blind, phase 3 trial, nonhospitalized patients with symptomatic Covid-19 and at least one risk factor for disease progression were randomized (1:1) to an intravenous infusion of sotrovimab 500 mg or placebo. The primary efficacy endpoint was the proportion of patients with Covid-19 progression, defined as hospitalization longer than 24 hours or death, through day 29.Results: In this preplanned interim analysis, which included an intent-to-treat population of 583 patients (sotrovimab, 291; placebo, 292), the primary efficacy endpoint was met. The risk of Covid-19 progression was significantly reduced by 85% (97.24% confidence interval, 44% to 96%; P = 0.002) with a total of three (1%) patients progressing to the primary endpoint in the sotrovimab group versus 21 (7%) patients in the placebo group. All five patients admitted to intensive care, including one who died by day 29, received placebo. Safety was assessed in 868 patients (sotrovimab, 430; placebo, 438). Adverse events were reported by 17% and 19% of patients receiving sotrovimab and placebo, respectively; serious adverse events were less common with sotrovimab (2%) versus placebo (6%). Conclusion:Sotrovimab reduced progression of Covid-19 in patients with mild/moderate disease, was well tolerated, and no safety signals were identified..

Background: Coronavirus disease 2019 (Covid-19) disproportionately results in hospitalization and death in older patients and those with underlying comorbidities. Sotrovimab is a pan-sarbecovirus monoclonal antibody designed to treat such high-risk patients early in the course of disease, thereby preventing Covid-19 progression. Methods: In this ongoing, multicenter, double-blind, phase 3 trial, nonhospitalized patients with symptomatic Covid-19 and at least one risk factor for disease progression were randomized (1:1) to an intravenous infusion of sotrovimab 500 mg or placebo. The primary efficacy endpoint was the proportion of patients with Covid-19 progression, defined as hospitalization longer than 24 hours or death, through day 29. Results: In this preplanned interim analysis, which included an intent-to-treat population of 583 patients (sotrovimab, 291; placebo, 292), the primary efficacy endpoint was met. The risk of Covid-19 progression was significantly reduced by 85% (97.24% confidence interval, 44% to 96%; P = 0.002) with a total of three (1%) patients progressing to the primary endpoint in the sotrovimab group versus 21 (7%) patients in the placebo group. All five patients admitted to intensive care, including one who died by day 29, received placebo. Safety was assessed in 868 patients (sotrovimab, 430; placebo, 438). Adverse events were reported by 17% and 19% of patients receiving sotrovimab and placebo, respectively; serious adverse events were less common with sotrovimab (2%) versus placebo (6%). Conclusion: Sotrovimab reduced progression of Covid-19 in patients with mild/moderate disease, was well tolerated, and no safety signals were identified. Funded by Vir Biotechnology, Inc. and GlaxoSmithKline; ClinicalTrials.gov NCT04545060

IMPORTANCEOlder patients and those with comorbidities who are infected with SARS-CoV-2 may be at increased risk of hospitalization and death. Sotrovimab is a neutralizing antibody for the treatment of high-risk patients to prevent COVID-19 progression.OBJECTIVE To evaluate the efficacy and adverse events of sotrovimab in preventing progression of mild to moderate COVID-19 to severe disease.DESIGN, SETTING, AND PARTICIPANTS Randomized clinical trial including 1057 nonhospitalized patients with symptomatic, mild to moderate COVID-19 and at least 1 risk factor for progression conducted at 57 sites in Brazil, Canada,