Among nonhospitalized adults with mild-to-moderate SARS-CoV-2 infection at high risk for progression to severe disease, treatment with the recombinant human immunoglobulin G1 monoclonal antibodies amubarvimab plus romlusevimab was safe and significantly reduced the risk for hospitalization and/or death, researchers report. “The study also shows clinical benefit of amubarvimab plus romlusevimab for up to 10 days from COVID-19 symptom onset,” write the authors. “Although initially approved in China, its utility in the United States with currently circulating Omicron subvariants is likely to be limited, although available in the future if new variants were shown to have in vitro susceptibility.”
Conducted in the U.S., Brazil, South Africa, Mexico, Argentina, and the Philippines, the phase 2 and 3 platform trial included nonhospitalized adults within 10 days of onset of symptomatic SARS-CoV-2 infection at high risk for clinical progression with COVID-19. The participants received the combination of amubarvimab plus romlusevimab or placebo, with these results: “Eight-hundred and seven participants who initiated the study intervention were included in the phase 3 analysis. Median age was 49 years (quartiles, 39 to 58); 51% were female, 18% were Black, and 50% were Hispanic or Latino. Median time from symptom onset at study entry was 6 days (quartiles, 4 to 7). Hospitalizations and/or death occurred in 9 (2.3%) participants in the amubarvimab plus romlusevimab group compared with 44 (10.7%) in the placebo group, with an estimated 79% reduction in events (P < 0.001). This reduction was similar between participants with 5 or less and more than 5 days of symptoms at study entry. Grade 3 or higher treatment-emergent adverse events through day 28 were seen less frequently among participants randomly assigned to amubarvimab plus romlusevimab (7.3%) than placebo (16.1%) (P < 0.001), with no severe infusion reactions or drug-related serious adverse events.”