A cohort study of more than 2,500 people found that the use of monoclonal antibodies to treat COVID-19 within two days of receiving a positive COVID-19 test reduced their risk of hospitalisation or death by 39 percent compared to persons who were eligible for monoclonal antibody treatment but did not receive it.
Persons with immunocompromising conditions experienced further reduced risk. The findings are published in Annals of Internal Medicine.
The U.S. Food and Drug Administration (FDA) granted emergency use authorisation to five different COVID-19 monoclonal antibody treatments at various times between 2020 and 2022. During this time, monoclonal antibody treatments were shown to have reduced COVID-19 viral load and later showed decreased rates of hospitalisation and death in some at-risk patients. All five of the previously authorised treatments have since been suspended or revoked by the FDA based on in vitro evidence of evolving loss of efficacy against new COVID-19 variants. However, these treatments were revoked without the availability of randomised trials or real-world data.
Researchers from the University of Pittsburgh Medical Center conducted a hypothetical pragmatic randomised trial of 2,571 patients treated with monoclonal antibodies who were matched with data from 5,135 patients with COVID-19 who were eligible for monoclonal antibodies but did not receive them. The authors found that treatment with monoclonal antibodies within two days of COVID-19 infection was associated with an estimated 39 percent lower risk for hospitalisation or death at 28 days.
According to the authors, their results indicate that throughout the pandemic, early treatment with monoclonal antibody treatment significantly reduced severity of COVID-19. They also emphasise that their findings should be interpreted with the knowledge that there are currently no FDA-approved monoclonal antibody treatments for treatment of outpatients with COVID-19, and that the rapid evolution of new variants warrants timely, continuous evaluation of both monoclonal antibody and non-monoclonal antibody treatment approaches.
