AstraZeneca antibody cocktail fails to prevent COVID symptoms: Study

AstraZeneca Plc’s antibody cocktail was only 33% effective at preventing Covid-19 symptoms in people who had been exposed to the virus, failing a study that was key to the drugmaker’s pandemic push.

The trial of 1,121 adult volunteers looked at whether the long-acting antibody combination could protect people who had recently been in contact with the SARS-CoV-2 virus in places like care homes. The company said it’s running other studies of the medicine that could help clarify the findings.


The outcomes are a blow an Astra for a drug that was hoped to be a bright spot in the company’s pandemic efforts following the mixed success of its vaccine with the University of Oxford Other drugmakers such as GlaxoSmithKline Plc have had some success in getting similar therapies through clinical tests and approved for people who are at risk of severing disease or can’t get vaccinated.

The study, conducted in the U.S. and U.K., showed 23 volunteers who got the AZD7442 cocktail developed symptomatic Covid-19 following exposure to the disease, compared with 17 cases in the placebo group. Twice as many participants got the antibody, but the difference between the two groups wasn’t considered statistically significant. The cocktail was well tolerated by participants.

Astra medicine attracted interest even before it could prove its efficacy. The U.S. has ordered up to 700,000 doses of the medicines for delivery in 2021, while the U.K was already reconsidering an earlier order for one million. Astra said Tuesday’s discussions with the U.S. government about the next steps were “ongoing”. Astra shares were little changed in London trading, rising 0.3%.

All the trial participants had been exposed to a person with Covid-19 in the past eight days. Further analysis showed the drug had some preventive effect.