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Prevention is better than cure

Sujata Chowdhury / Alamy Stock Vector

A treatment made up of a combination of two neutralizing antibodies against the SARS-CoV-2 spike protein (REGEN-COV) has been shown to reduce the rates of hospitalization or death in patients with COVID-19.

To evaluate whether REGEN-COV could also help to prevent infection, O’Brien et al. recruited household contacts of people with COVID-19 into a randomized phase 3 trial. Participants were recruited within 96 hours of household contact with an infected person and were randomly assigned to receive a subcutaneous injection of either REGEN-COV or placebo.

The authors found that in the weeks after treatment, the risk of developing symptomatic COVID-19 was reduced by over 80% in the REGEN-COV group relative to that in the placebo group. For those who developed symptomatic disease, REGEN-COV shortened the duration of symptoms and reduced the viral load; the risk of developing asymptomatic COVID-19 was also reduced, and there were no safety issues with the treatment.

While vaccine rollout is ongoing, many people remain vulnerable to infection with SARS-CoV-2 and associated complications. REGEN-COV may be useful for the protection of high-risk people, such as those who are immunocompromised.

N. Engl. J. Med. (2021)



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