Comparative Efficacy of Early COVID-19 Monoclonal Antibody Therapies: A Retrospective Analysis

Savanna San Filippo; Brynna Crovetto; John Bucek; Ronald G Nahass; Marc Milano; Luigi Brunetti

doi:10.1093/ofid/ofac080

Comparative Efficacy of Early COVID-19 Monoclonal Antibody Therapies: A Retrospective Analysis

Open Forum Infect Dis. 2022 Feb 14;9(4):ofac080. doi: 10.1093/ofid/ofac080. eCollection 2022 Apr.

Authors

Savanna San Filippo¹, Brynna Crovetto¹, John Bucek¹, Ronald G Nahass², Marc Milano¹, Luigi Brunetti^{1

3}

Affiliations

¹ Robert Wood Johnson University Hospital Somerset, Somerville, New Jersey, USA.
² IDCare, Hillsborough, New Jersey, USA.
³ Ernest Mario School of Pharmacy, Rutgers, The State University of New Jersey, Piscataway, New Jersey, USA.

Abstract

Background: Bamlanivimab and casirivimab/imdevimab are monoclonal antibody (mAb) treatments used for mild to moderate coronavirus disease 2019 (COVID-19) in high-risk patients. To date, there are few data summarizing real-world evidence comparing the 2 mAbs. Additionally, there are insufficient data to guide administration timing relative to symptom onset. The purpose of this study was to evaluate 30-day failure rates for each agent and to identify the relationship between symptom onset and efficacy.

Methods: We performed a retrospective cohort study of a 6-month period at a large community medical center. Consecutive outpatients diagnosed with COVID-19 disease by nasopharyngeal (NP) polymerase chain reaction (PCR) testing received either bamlanivimab 700 mg or casirivimab/imdevimab 1200 mg/1200 mg. Each patient was followed for a total of 30 days. Three independent, blinded physicians performed adjudication for revisit reasons. The primary outcome was therapy-related failure, defined as COVID-19-related hospital admission within 30 days of infusion. Multivariable logistic regression was performed to adjust for confounders that may have influenced hospital admission in either group.

Results: During the period from November 2020 to May 2021, 183 patients were treated with bamlanivimab and 270 with casirivimab/imdevimab. The mean age was ~67 years and body mass index 30 kg/m². Thirty-day admission for therapy-related failure rates were 4.8% and 13.7% for casirivimab/imdevimab and bamlanivimab, respectively (P = .001). No significant differences were found between early (<3 days of symptom onset) and late administration of either mAb.

Conclusions: There was a higher failure rate with bamlanivimab vs casirivimab/imdevimab. No difference in efficacy was found between early vs late administration of either mAb.

Keywords: COVID-19; SARS-CoV-2; antispike protein; comparative efficacy; coronavirus; protein therapeutics.