Cohen, Myron S.Nirula, AjayMulligan, Mark J.Novak, Richard M.Marovich, MaryYen, CatherineStemer, AlexanderMayer, Stockton M.Wohl, DavidBrengle, BlairMontague, Brian T.Frank, IanMcCulloh, Russell J.Fichtenbaum, Carl J.Lipson, BradGabra, NashwaRamirez, Julio A.Thai, ChristineChege, WairimuGomez Lorenzo, Margarita M.Sista, NirupamaFarrior, JenniferClement, Meredith E.Brown, Elizabeth R.Custer, Kenneth L.Van Naarden, JacobAdams, Andrew C.Schade, Andrew E.Dabora, Matan C.Knorr, JackPrice, Karen L.Sabo, JanelleTuttle, Jay L.Klekotka, PaulShen, LeiSkovronsky, Daniel M.2021-11-022021-11-022021-06-03Cohen, M. S., Nirula, A., Mulligan, M. J., Novak, R. M., Marovich, M., Yen, C., Stemer, A., Mayer, S. M., Wohl, D., Brengle, B., Montague, B. T., Frank, I., McCulloh, R. J., Fichtenbaum, C. J., Lipson, B., Gabra, N., Ramirez, J. A., Thai, C., Chege, W., … Taffet, G. (2021). Effect of Bamlanivimab vs Placebo on Incidence of COVID-19 Among Residents and Staff of Skilled Nursing and Assisted Living Facilities: A Randomized Clinical Trial. JAMA. https://doi.org/10.1001/jama.2021.88280098-7484https://hdl.handle.net/1805/26920Importance Preventive interventions are needed to protect residents and staff of skilled nursing and assisted living facilities from COVID-19 during outbreaks in their facilities. Bamlanivimab, a neutralizing monoclonal antibody against SARS-CoV-2, may confer rapid protection from SARS-CoV-2 infection and COVID-19. Objective To determine the effect of bamlanivimab on the incidence of COVID-19 among residents and staff of skilled nursing and assisted living facilities. Design, Setting, and Participants Randomized, double-blind, single-dose, phase 3 trial that enrolled residents and staff of 74 skilled nursing and assisted living facilities in the United States with at least 1 confirmed SARS-CoV-2 index case. A total of 1175 participants enrolled in the study from August 2 to November 20, 2020. Database lock was triggered on January 13, 2021, when all participants reached study day 57. Interventions Participants were randomized to receive a single intravenous infusion of bamlanivimab, 4200 mg (n = 588), or placebo (n = 587). Main Outcomes and Measures The primary outcome was incidence of COVID-19, defined as the detection of SARS-CoV-2 by reverse transcriptase–polymerase chain reaction and mild or worse disease severity within 21 days of detection, within 8 weeks of randomization. Key secondary outcomes included incidence of moderate or worse COVID-19 severity and incidence of SARS-CoV-2 infection. Results The prevention population comprised a total of 966 participants (666 staff and 300 residents) who were negative at baseline for SARS-CoV-2 infection and serology (mean age, 53.0 [range, 18-104] years; 722 [74.7%] women). Bamlanivimab significantly reduced the incidence of COVID-19 in the prevention population compared with placebo (8.5% vs 15.2%; odds ratio, 0.43 [95% CI, 0.28-0.68]; P < .001; absolute risk difference, −6.6 [95% CI, −10.7 to −2.6] percentage points). Five deaths attributed to COVID-19 were reported by day 57; all occurred in the placebo group. Among 1175 participants who received study product (safety population), the rate of participants with adverse events was 20.1% in the bamlanivimab group and 18.9% in the placebo group. The most common adverse events were urinary tract infection (reported by 12 participants [2%] who received bamlanivimab and 14 [2.4%] who received placebo) and hypertension (reported by 7 participants [1.2%] who received bamlanivimab and 10 [1.7%] who received placebo). Conclusions and Relevance Among residents and staff in skilled nursing and assisted living facilities, treatment during August-November 2020 with bamlanivimab monotherapy reduced the incidence of COVID-19 infection. Further research is needed to assess preventive efficacy with current patterns of viral strains with combination monoclonal antibody therapy.enPublisher PolicyAntiviral AgentsHealth PersonnelSeverity of Illness IndexCOVID-19Article