Pharmaceutical AstraZeneca announced on Tuesday that a study of its treatment with monoclonal antibodies, AZD7442, does not meet the main objective of preventing symptomatic Covid-19 in people recently exposed to the new coronavirus.

The company has explained that the participants in the trial were unvaccinated adults over 18 years of age with confirmed exposure to a person with the coronavirus in the last eight days.

AZD7442 reduced the risk of developing symptomatic Covid-19 by 33% compared to a placebo, which was not statistically significant, the company has reported. "While this trial did not meet the primary endpoint against symptomatic disease, we are encouraged by the protection seen in PCR-negative participants after AZD7442 treatment," AstraZeneca Executive Vice President Mene Pangalos said in a statement.

AstraZeneca is also studying the treatment in a trial of pre-exposed patients and to prevent more serious diseases. Monoclonal antibody therapy is in a class of drugs that mimics the natural antibodies the body makes to fight infection.

Rivals Regeneron Pharmaceuticals Inc and Eli Lilly & Co have developed monoclonal antibody therapies that have been licensed for use in the United States to treat patients infected with the virus.

The European Medicines Agency (EMA) has approved Regeneron's therapy and is reviewing similar drugs from Eli Lilly, Celltrion, and one developed by GlaxoSmithKline and Vir Biotechnology Inc.

Read the full AstraZeneca statement

NOTE: The information in this article is not intended to influence your decision whether to be vaccinated. You should conduct your own research when making a decision.