Bamlanivimab use in mild-to-moderate COVID-19 disease: A matched cohort design

Study objective: Our objective was to determine if bamlanivimab (LY-CoV555; BAM), a monoclonal antibody for mild-to-moderate Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-Co-V-2, prevented emergency department (ED) visits, hospitalizations for SARS-CoV-2, or death within 60 days of a positive SARS-CoV-2 viral test.

Design: Patient propensity matching was performed for BAM administration to get two discrete groups of patients; those who received BAM (N = 117) and those who did not (N = 117).

Setting: Outpatients (N = 2107) eligible to receive BAM from November 1 to December 31, 2020, were identified.

Patients: A total of 144 of 2107 patients with mild-to-moderate SARS-CoV-2 received BAM INTERVENTION: Eligible patients had mild-to-moderate SARS-CoV-2 disease, a positive SARS-CoV-2 test, and risk factor(s) for progression to severe SARS-CoV-2 infection. All patients were reviewed for subsequent ED visits, subsequent hospitalization, and death.

Measurements and main results: Patients (N = 234) were matched, 117 in each group. Median (interquartile range) age was 72 (65-80) years. Forty-seven percent of patients were male. Twenty-one patients who received BAM were subsequently seen in the ED compared to 34 untreated patients (18.0% vs. 29.1%; p = 0.045). Fourteen BAM-treated patients were subsequently hospitalized post-BAM infusion compared to 27 untreated patients (12.0% vs. 23.1%; p = 0.025). Finally, there were no mortalities in the BAM group, however, eleven patients in the untreated group died (0.0% vs. 9.4%; p < 0.001). The number needed to treat (NNT) is 11 patients to prevent one mortality event.

Conclusions: BAM infusion for mild-to-moderate SARS-CoV-2 infection in outpatients significantly prevented subsequent ED visits, hospitalizations, and death from SARS-CoV-2.