AstraZeneca’s antibody cocktail failed to prevent COVID-19 symptoms in trial participants recently exposed to the virus, the company announced Monday. The cocktail, AZD7442, a long-acting antibody combination, was given to unvaccinated adults 18 years and older who had confirmed exposure to the virus within the past eight days.
The STORM CHASER trial, which included 1,121 participants, was set up in a 2:1 randomized AZD7442 to placebo, and resulted in 23 cases of symptomatic COVID-19 infections among those who received the antibody cocktail versus 17 in the placebo arm.
Overall, the company said AZD7442 was found to reduce the risk of developing symptomatic COVID-19 by 33% compared to placebo, "which was not statistically significant."
However, the research team was encouraged by results pertaining to patients in the trial who were already infected with COVID-19 at the time of dosing, and said analysis is ongoing.
"The results of STORM CHASER suggest that AZD7442 may be useful in preventing symptomatic COVID-19 in individuals not already infected," Myron J. Levin, M.D., professor of pediatrics and medicine at University of Colorado School of Medicine, and principal trial investigator, said in a news release. "The PROVENT trial will give us more clarity in this patient population. While COVID-19 vaccination efforts have been successful, there is still a significant need for more prevention and treatment options for certain populations, including those unable to be vaccinated or those who may have an inadequate response to vaccination."