Effect of Bamlanivimab as Monotherapy or in Combination with Etesevimab or Sotrovimab on Persistently High Viral Load in Patients with Mild-to-Moderate COVID-19: A Randomized, Phase 2 BLAZE-4 Trial

Introduction Treatment with monoclonal antibodies provides rapid, passive immunity and may stop COVID-19 disease progression. The study evaluated the effect of bamlanivimab (BAM) or BAM + etesevimab (ETE)/sotrovimab compared to placebo on SARS-CoV-2 viral load in patients with COVID-19. Methods The phase 2, randomized, single-dose study included patients aged between ≥ 18 and 5.27 on day 7 (persistently high viral load [PHVL]) who received BAM or BAM + (ETE or sotrovimab). Results A total of 725 patients, mean age 39.6 years (range 18–75 years), 50.2% male were randomized and infused with study drug in arms 1–6; and a total 202 patients, mean age 38 years (range 18–63 years), 53.5% female were randomized and infused with study drug in arms 7 and 8. A significantly lower proportion of patients in arms 2–6 and arm 7 experienced PHVL on day 7 compared to placebo. On day 7, patients in arms 2, 3, and 6 consistently experienced significantly greater reduction in viral load than placebo. Significant improvement was observed in time to viral load clearance and time to symptom improvement by day 29 in some arms compared to placebo. No new safety concerns were observed with drug combinations. Conclusion The study demonstrated that a significantly lower proportion of patients with mild-to-moderate COVID-19 treated with BAM or BAM + (ETE or sotrovimab) experienced a PHVL at day 7. Trial Registration ClinicalTrials.gov identifier, NCT04634409.