AstraZeneca’s antibody cocktail fails to prevent Covid-19 symptoms in study

The British-Swedish pharma’s cocktail showed only 33% efficacy in recent trial, failing to meet primary objective.


On Tuesday, the company announced its antibody cocktail named AZD7442 - a mixture of two different monoclonal antibodies, had yielded unsatisfactory results in its recent Phase 3 clinical trial. Running in both the UK and the US, the trial enrolled 1,121 participants who had recent contact with a Covid-19 infected person to assess if the treatment could prevent Covid-19 symptoms. Participants were enrolled in a 2: 1 ratio, into an AZD7442 arm and a placebo arm, respectively. Results indicated 23 cases of symptomatic Covid-19 in the AZD7442 arm and 17 cases in the placebo arm, and thus showing the treatment did not induce a statistically significant decrease in the risk of symptomatic Covid-19 after exposure.

Nevertheless, the trial results were more encouraging when the treatment was given to participants who initially tested negative for the virus, reducing the risk of developing the condition by 73 %. The company’s Executive Vice President of research and development, Mene Pangalos said in a statement; “While this trial did not meet the primary endpoint against symptomatic illness, we are encouraged by the protection seen in the PCR negative participants following treatment with AZD7442". The company is committed to new research to reactivate the vaccine’s capability. Five more trials are in progress, testing the antibody cocktail as treatment or prevention. The treatment is separate from the company’s vaccines, which are being used globally to protect against Covid-19.