The COVID-19 pandemic has disproportionately affected residents of skilled nursing and assisted living facilities. Interventions are urgently needed to protect this vulnerable population. Bamlanivimab is a potent neutralizing monoclonal antibody that binds the receptor-binding domain of the spike protein of SARS-CoV-2. This study evaluates the safety and efficacy of bamlanivimab in preventing COVID-19.
BLAZE-2 is a Phase 3, randomized, double-blind, placebo-controlled, single-dose study that enrolled residents and staff at skilled nursing and assisted living facilities reporting at least one confirmed SARS-CoV-2 case. Eligible participants received bamlanivimab (4200 mg) or placebo intravenously. Nasal swabs were collected at baseline and weekly through day 57 to determine SARS-CoV-2 infection status via reverse transcriptase polymerase chain reaction (RT-PCR). COVID-19-releated symptoms and signs were recorded daily. The primary analysis prevention population included participants negative at baseline for SARS-CoV-2 by RT-PCR and serology. The primary endpoint was incidence of mild or worse COVID-19 by day 57.
Of the 1175 participants dosed, 966 (82.2%) comprised the prevention population. The prevention population included 299 residents for whom the median age was 76 years (range 31-104), 234 (78.3%) were aged ?65, and 178 (59.5%) were female. All were considered at high risk for development of severe COVID-19. The proportion of residents in the prevention population with mild or worse COVID-19 by day 57 was significantly lower in the bamlanivimab group compared with the placebo group (odds ratio [OR], 0.20; 95% confidence interval [CI], 0.08 to 0.49; p<0.001)(Figure). For this same group, bamlanivimab was associated with significant reductions in the incidence of moderate or worse COVID-19 by day 57 (OR, 0.20; 95% CI, 0.08 to 0.49; p<0.001) and incident SARS-CoV-2 infection by day 29 (OR, 0.23; CI, 0.11 to 0.48; p<0.001) compared with placebo. Of the 16 deaths reported during the study, all 5 that were attributed to COVID-19 were in the placebo group. The incidence of both adverse events and serious adverse events were balanced between the bamlanivimab and placebo group.
Bamlanivimab was highly effective in reducing the incidence of symptomatic COVID-19 and SARS-CoV-2 infection and was well tolerated. These findings demonstrate the potential beneficial impact of bamlanivimab use on COVID-19 morbidity and mortality among skilled nursing facility residents.