Effect of the Neutralizing SARS-CoV-2 Antibody Sotrovimab in Preventing Progression of COVID-19: A Randomized Clinical Trial

ABSTRACT

ImportanceOlder patients and those with underlying comorbidities infected with SARS-CoV-2 may be at increased risk of hospitalization and death from COVID-19. Sotrovimab is a neutralizing antibody designed for treatment of high-risk patients to prevent COVID-19 progression. ObjectiveTo evaluate the efficacy and safety of sotrovimab in preventing progression of mild to moderate COVID-19 to severe disease. DesignRandomized, double-blind, multicenter, placebo-controlled, phase 3 study. Setting57 centers in 5 countries. ParticipantsNonhospitalized patients with symptomatic, mild to moderate COVID-19 and at least 1 risk factor for disease progression. InterventionPatients were randomized (11) to an intravenous infusion of sotrovimab 500 mg or placebo. Main Outcomes and MeasuresThe primary efficacy outcome was the proportion of patients with COVID-19 progression, defined as all-cause hospitalization longer than 24 hours for acute illness management or death through day 29. Key secondary outcomes included the proportion of patients with COVID-19 progression, defined as emergency room visit, hospitalization of any duration, or death, and proportion of patients developing severe/critical respiratory COVID-19 requiring supplemental oxygen. ResultsAmong 1057 patients randomized (sotrovimab, 528; placebo, 529), all-cause hospitalization longer than 24 hours or death was significantly reduced with sotrovimab (6/528 [1%]) vs placebo (30/529 [6%]) by 79% (95% CI, 50% to 91%; P<.001). Secondary outcome results further demonstrated the effect of sotrovimab in reducing emergency room visits, hospitalization of any duration, or death, which was reduced by 66% (95% CI, 37% to 81%; P<.001), and severe/critical respiratory COVID-19, which was reduced by 74% (95% CI, 41% to 88%; P=.002). No patients receiving sotrovimab required high-flow oxygen, oxygen via nonrebreather mask, or mechanical ventilation compared with 14 patients receiving placebo. The proportion of patients reporting adverse events was similar between treatment groups; sotrovimab was well tolerated, and no safety concerns were identified. Conclusions and RelevanceAmong nonhospitalized patients with mild to moderate COVID-19, a single 500-mg intravenous dose of sotrovimab prevented progression of COVID-19, with a reduction in hospitalization and need for supplemental oxygen. Sotrovimab is a well-tolerated, effective treatment option for patients at high risk for severe morbidity and mortality from COVID-19. Trial RegistrationClinicalTrials.gov Identifier NCT04545060