Abstract
BACKGROUND: Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the causative agent of coronavirus disease 2019 (COVID-19), was first identified in 2019 in Wuhan, China, and has rapidly spread across the world. As of April 2021, SARS-CoV-2 has infected more than 140,000,000 and caused more than 3,000,000 deaths globally. In November 2020, the monoclonal antibody bamlanivimab was approved by the FDA for non-hospitalized patients with SARS-CoV-2 (COVID-19) who possessed risk factors for progression to severe COVID-19. This provided a treatment option that may help prevent hospitalization. METHODS: Patients who regularly received ambulatory care at a military treatment facility and who were diagnosed with mild-to-moderate COVID-19 and possessed risk factors for progression to severe COVID-19 were treated with a single, intravenous infusion (700 mg) of the virus-neutralizing monoclonal antibody bamlanivimab. The primary outcome was improvement of self-reported symptoms within 24 to 72 hours of receiving the infusion. The secondary outcome was prevention of disease progression requiring emergency department (ED) utilization or hospitalization related to COVID-19 within 30 days of infusion. Bamlanivimab was administered in accordance with the FDA's approval and Defense Health Agency's guidance, including follow-up within 72 hours of administration. Institutional Review Board (IRB) approval was obtained. RESULTS: Of the COVID-19 patients who were given the option of a bamlanivimab infusion, 40 accepted and 6 did not (40/46, 86.9%). Thirty-six of 40 patients in the treatment group were contacted within 72 hours. ED/hospitalization information was available for all 46 patients. In the treatment group, 94.4% (34/36) reported global improvement. Three of 40 (7.5%) patients in the treatment group required inpatient admission, and 2 of 40 patients (5%) required ED evaluation within 30 days of infusion. Therefore, 5 of 40 (12.5%) patients required evaluation shortly after infusion, while 2 of 6 (33.3%) patients who declined treatment required hospital evaluation or admission related to COVID-19 within 30 days of infusion (P = .15). CONCLUSIONS: Global improvement of symptoms within 24 to 72 hours of infusion was reported by 94.4% of patients receiving bamlanivimab; however, statistical significance could not be determined due to the small sample size and lack of placebo group due to study design. Furthermore, ED visits and hospital admissions were analyzed, but with only six patients in the comparison group, the relative risk was not statistically significant and could not be precisely estimated. In the future, this study can be replicated with both larger control/treatment arms to validate the initial results of this small, retrospective, cohort study.