Monoclonal Antibodies Help Covid-19 Patients Avoid Hospitalization

ROCHESTER, MN. ― In a large observational study, Mayo Clinic researchers have shown that two monoclonal antibodies administered separately helped prevent hospitalization in high-risk patients who became infected with COVID-19. The study also showed more hospitalizations were observed among patients with more comorbidities. The findings appear in The Journal of Infectious Diseases.

“The real-world data reported in this study confirm what has been seen in clinical trials involving a placebo,” says Raymund Razonable, M.D. , a Mayo Clinic infectious diseases specialist. “Monoclonal antibodies are associated with a low rate of hospitalizations, provided patients received them early on in the course of their COVID-19 infection.” Dr. Razonable is senior author of the study.

The researchers reviewed patient outcomes among a population of 3,596 patients from across Mayo Clinic with a median age of 62. All patients had at least one condition that made them high-risk, and just over half had multiple comorbidities. Patients received bamlanivimab or casirivimab-imdevimab infusion. After 28 days, the hospitalization rate due to COVID-19 was 2.56%. After adjusting for comorbidities, no significant difference was observed in the hospitalization rate between the two monoclonal antibodies.

It is important to note that this study was conducted between November 2020 and February, which is before COVID-19 variants were discovered.

While casirivimab-imdevimab remains active against COVID-19 variants, the Food and Drug Administration no longer authorizes bamlanivimab alone as an emergency use treatment. Bamlanivimab is now authorized only as part of a drug combination with etesevimab. Still the authors say this study is an important confirmation that monoclonal antibody use effectively treats high-risk patients with COVID-19.

The study was funded by Mayo Clinic.