Impact of COVID vaccine and comorbidities in patients receiving casirivimab-imdevimab monoclonal antibody during SARS-CoV-2 B.1.617.2 (Delta) surge: A real-world study

Abstract

Background: Several randomized trials and real-world studies depicted the role of monoclonal antibody infusion in reducing hospitalization, and halting progression from asymptomatic to symptomatic COVID pneumonia, viral titer, and death. No data exists to show outcomes of patients who received casirivimab-imdevimab infusion based on their vaccination status and underlying comorbidities. This study aims to provide outcomes of casirivimab-imdevimab treatment during the SARS-CoV-2 B1.617.2 (Delta) surge among fully vaccinated and not fully vaccinated individuals.

Methods: COVID-19-positive patients who received casirivimab-imdevimab infusion during the Delta surge were analyzed to compare their underlying comorbidities and the rate of 28-days all-cause and COVID-related ED visits or hospitalization, among fully vaccinated and not fully vaccinated individuals.

Results: A total of 3,586 patients received casirivimab-imdevimab infusion. COVID-related hospitalizations were directly related to the number of comorbidities (OR:1.745, 95 % CI:1.469-2.074). Vaccinated patients with ≥3 comorbidities had lower rates of 28-day COVID-related ED visits or hospitalization (p = 0.044) and those with ≥4 comorbidities had lower rates of 28-day All-cause ED visits or hospitalization (p = 0.029). Hypertension (OR:2.418, 95 %CI:1.341-4.360), immunocompromised state (OR:5.250, 95 %CI: 1.912-14.417), age ≥ 65 (OR:4.045, 95 %CI:2.224-7.358) increased the probability of hospitalization due to COVID and being fully vaccinated lowered the likelihood of hospitalization (OR: 0.472, 95 %CI: 0.239-0.933). Vaccinated patients had a lower length of COVID-related hospitalization (2 days vs 4.5 days, p < 0.001).

Conclusion: COVID vaccination status and comorbidities are significant predictors of outcomes after casirivimab-imdevimab treatment. Despite having higher comorbidities, patients who were fully vaccinated at the time of casirivimab-imdevimab infusion had a lower length of hospitalization and reduced 28-day COVID ED visits or hospitalizations. Future trials should also compare outcomes based on the patient's vaccination status.

Keywords: COVID vaccine; COVID-19; Comorbidities; Delta variant; Monoclonal antibody.