Intramuscular Versus Intravenous SARS-CoV-2 Neutralizing Antibody Sotrovimab for Treatment of COVID-19 (COMET-TAIL): A Randomized Non-inferiority Clinical Trial (preprint)

Background: Convenient administration of coronavirus disease 2019 (COVID-19) treatment in community settings is desirable. Sotrovimab is a pan-sarbecovirus dual-action monoclonal antibody formulated for intravenous (IV) or intramuscular (IM) administration for early treatment of mild/moderate COVID-19. Methods: This phase 3, randomized, multicenter, open-label study tested non-inferiority of IM to IV administration using a 3.5% absolute non-inferiority margin. From June to August 2021, patients aged [≥]12 years with COVID-19, not hospitalized or receiving supplemental oxygen, and at high risk for progression were randomized 1:1:1 to a single 500-mg IV sotrovimab infusion or 500-mg or 250-mg IM sotrovimab injection. The primary composite endpoint was progression to all-cause hospitalization for >24 hours for acute management of illness or all-cause death through day 29. Results: Sotrovimab 500 mg IM was non-inferior to 500 mg IV: 10/376 (2.7%) participants in the sotrovimab 500-mg IM group versus 5/378 (1.3%) in the sotrovimab 500-mg IV group met the primary endpoint (absolute adjusted risk difference: 1.06% [95% confidence interval [CI]: -1.15%, 3.26%]). The CI upper limit was lower than the prespecified non-inferiority margin of 3.5%. 250-mg IM group enrollment was discontinued early because a greater proportion of hospitalizations was seen in that group versus the 500-mg groups. Serious adverse events occurred in <1% to 2% of participants across groups. Four participants experienced serious disease related events and died (500 mg IM: 2/393 [<1%]; 250 mg IM: 2/195 [1%]). Conclusions: Sotrovimab 500-mg IM injection was well tolerated and non-inferior to IV administration. IM administration could expand outpatient treatment access for COVID-19.

Safety, Virology, Pharmacokinetics, and Clinical Experience of High-dose Intravenous Sotrovimab for the Treatment of Mild to Moderate COVID-19: An Open-label Clinical Trial (preprint)

Background: 500 mg intravenous (IV) sotrovimab has been shown to be well tolerated and efficacious against pre-Omicron strains in treating patients with mild to moderate coronavirus disease 2019 (COVID-19) at high risk for disease progression. Methods: This was an open-label, single-arm substudy of phase 3 COMET-TAIL (NCT04913675) assessing the safety and tolerability of a 2000 mg IV dose of sotrovimab. Symptomatic patients (aged [≥]18 years) with COVID-19 at high risk for progression were enrolled from June 30 through July 11, 2022, when Omicron BA.5, BA.2.12.1, and BA.4 were the predominant circulating variants in the United States. The primary endpoint was occurrence of adverse events (AEs), serious AEs (SAEs), AEs of special interest, and COVID-19 disease-related events (DREs) through Day 8. Safety, pharmacokinetics, viral load, and hospitalization >24 hours for acute management of illness or death through Day 29 were assessed. Results: All participants (n=81) were Hispanic, 58% were female, and 51% were aged [≥]55 years. Through Day 8, no AEs, including infusion-related reactions or hypersensitivity, were reported; 2 participants reported DREs (mild cough, n=2). One SAE (acute myocardial infarction), which was considered unrelated to sotrovimab or COVID-19 by the investigator, occurred on Day 27 and was the only hospitalization reported. Maximum serum concentration (geometric mean) was 745.9 g/mL. Viral load decreased from baseline through Day 29; only 2 participants (3%) had persistently high viral load ([≥]4.1 log10 copies/mL) at Day 8. Conclusions: 2000 mg IV sotrovimab was well tolerated, with no new unanticipated safety signals observed.

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

Importance: Older 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. Objective: To evaluate the efficacy and safety of sotrovimab in preventing progression of mild to moderate COVID-19 to severe disease. Design: Randomized, double-blind, multicenter, placebo-controlled, phase 3 study. Setting: 57 centers in 5 countries. Participants: Nonhospitalized patients with symptomatic, mild to moderate COVID-19 and at least 1 risk factor for disease progression. Intervention: Patients were randomized (1:1) to an intravenous infusion of sotrovimab 500 mg or placebo. Main Outcomes and Measures: The 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. Results: Among 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