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Bamlanivimab plus Etesevimab in Mild or Moderate Covid-19
Michael Dougan1, Ajay Nirula1, Masoud Azizad1
1From Massachusetts General Hospital and Harvard Medical School, Boston (M. Dougan); Eli Lilly (A.N., A.C.A., J.V.N., K.L.C., M. Durante, G.O., A.E.S., T.R.H., P.J.E., R.E.H., N.L.K., J.S., D.R.P., M.C.D., P. Klekotka, L.S., D.M.S.), and Franciscan Health (I.S.) - both in Indianapolis; Valley Clinical Trials-Northridge, Northridge (M.A.), the Department of Medicine, Women's Guild Lung Institute, Cedars-Sinai Medical Center, Los Angeles (P.C.), and Long Beach Clinical Trials, Long Beach (B.H.) - all in California; the Las Vegas Medical Research Center, Las Vegas (B.M.); Baylor University Medical Center and Baylor Scott and White Research Institute, Dallas (R.L.G.), and Gadolin Research, Beaumont (R.P.) - both in Texas; NOLA Research Works, New Orleans (C.H.), and Clinical Trials of Southwest Louisiana, Lake Charles (J.M.) - both in Louisiana; Vitalink Research, Union, SC (J.B.); Eastside Research Associates, Redmond, WA (C.C.); Monroe Biomedical Research, Monroe, NC (A.I.); Cook County Health, Chicago (G.H.); Indago Research and Health Center, Hialeah, FL (J.C.); and Georgetown University, Washington, DC (P. Kumar).
Insights
Neutralizing monoclonal antibodies like bamlanivimab-etesevimab offer immediate protection against severe COVID-19. This treatment significantly reduced hospitalizations and deaths in high-risk patients compared to placebo.
Area of Science:
- Immunology
- Virology
- Clinical Medicine
Background:
- Patients with underlying health conditions face higher risks of severe COVID-19.
- While vaccines build immunity over time, monoclonal antibody treatments provide rapid, passive immunity.
- These treatments can potentially limit disease progression and reduce complications.
Purpose of the Study:
- To evaluate the efficacy of a neutralizing monoclonal antibody combination (bamlanivimab and etesevimab) in high-risk ambulatory patients with mild to moderate COVID-19.
- To assess the impact of this treatment on COVID-19-related hospitalization or death.
- To determine the effect on severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) viral load.
Main Methods:
- A Phase 3 randomized trial assigned high-risk ambulatory patients with mild/moderate COVID-19 to receive either bamlanivimab-etesevimab or placebo via intravenous infusion.
- Treatment was administered within 3 days of a positive SARS-CoV-2 laboratory diagnosis.
- The primary outcome measured was COVID-19-related hospitalization or all-cause death by day 29.
Main Results:
- The bamlanivimab-etesevimab group showed significantly lower rates of hospitalization or death (2.1%) compared to the placebo group (7.0%) by day 29.
- No deaths occurred in the treatment group, versus 10 deaths in the placebo group (9 deemed COVID-19-related).
- A greater reduction in SARS-CoV-2 viral load was observed by day 7 in patients receiving bamlanivimab-etesevimab.
Conclusions:
- Bamlanivimab plus etesevimab effectively reduced the incidence of COVID-19-related hospitalization and death in high-risk ambulatory patients.
- The treatment also accelerated viral load decline, indicating a direct impact on the virus.
- This monoclonal antibody combination offers a promising therapeutic option for early intervention in high-risk COVID-19 cases.
Background:
Patients with underlying medical conditions are at increased risk for severe coronavirus disease 2019 (Covid-19). Whereas vaccine-derived immunity develops over time, neutralizing monoclonal-antibody treatment provides immediate, passive immunity and may limit disease progression and complications.
Methods:
In this phase 3 trial, we randomly assigned, in a 1:1 ratio, a cohort of ambulatory patients with mild or moderate Covid-19 who were at high risk for progression to severe disease to receive a single intravenous infusion of either a neutralizing monoclonal-antibody combination agent (2800 mg of bamlanivimab and 2800 mg of etesevimab, administered together) or placebo within 3 days after a laboratory diagnosis of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. The primary outcome was the overall clinical status of the patients, defined as Covid-19-related hospitalization or death from any cause by day 29.
Results:
A total of 1035 patients underwent randomization and received an infusion of bamlanivimab-etesevimab or placebo. The mean (±SD) age of the patients was 53.8±16.8 years, and 52.0% were adolescent girls or women. By day 29, a total of 11 of 518 patients (2.1%) in the bamlanivimab-etesevimab group had a Covid-19-related hospitalization or death from any cause, as compared with 36 of 517 patients (7.0%) in the placebo group (absolute risk difference, -4.8 percentage points; 95% confidence interval [CI], -7.4 to -2.3; relative risk difference, 70%; P<0.001). No deaths occurred in the bamlanivimab-etesevimab group; in the placebo group, 10 deaths occurred, 9 of which were designated by the trial investigators as Covid-19-related. At day 7, a greater reduction from baseline in the log viral load was observed among patients who received bamlanivimab plus etesevimab than among those who received placebo (difference from placebo in the change from baseline, -1.20; 95% CI, -1.46 to -0.94; P<0.001).
Conclusions:
Among high-risk ambulatory patients, bamlanivimab plus etesevimab led to a lower incidence of Covid-19-related hospitalization and death than did placebo and accelerated the decline in the SARS-CoV-2 viral load. (Funded by Eli Lilly; BLAZE-1 ClinicalTrials.gov number, NCT04427501.).
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