Anglo-Swedish drugmaker AstraZeneca said on Tuesday a study of its monoclonal antibody treatment, AZD7442, did not meet the main goal of preventing symptomatic COVID-19 in people recently exposed to the novel coronavirus.

The company said the participants in the trial were unvaccinated adults older than 18 years with confirmed exposure to a person with the coronavirus within the past eight days.

AZD7442 reduced the risk of developing symptomatic COVID-19 by 33% compared to a placebo, which was not statistically significant, the company reported. AstraZeneca is also studying the treatment in a pre-exposed patients trial and for preventing more severe disease.

Rivals Regeneron Pharmaceuticals Inc and Eli Lilly & Co have similar monoclonal antibody products that have been authorised for use.