AstraZeneca antibody fails to prevent Covid in exposed patients

Trial participants were unvaccinated adults older than 18 years with confirmed exposure to a person with the coronavirus, AstraZeneca said in a statement.

AZD7442 reduced the risk of developing symptomatic COVID-19 by 33% compared to a placebo, which was not statistically significant, it added.

The trial included 1,121 participants in a 2:1 randomisation AZD7442-to-placebo, with 23 cases of symptomatic Covid-19 accrued in the AZD7442 arm (23/749) and 17 cases accrued in the placebo arm (17/372). All participants had a negative SARS-CoV-2 antibody test on the day of dosing to exclude prior infection, and a nasopharyngeal swab was also collected and subsequently analysed for SARS-CoV-2 using an RT-PCR test to detect the virus.

“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,” said AstraZeneca executive vice president Mene Pangalos

AstraZeneca is also studying the treatment in a pre-exposed patients trial and for preventing more severe disease.

AZD7442 is being developed with support from the US government. The company in March announced a deal with Washington to supply up to 500,000 doses of AZD7442 for $205m. The company said on Tuesday talks with officials regarding next steps on the deal are ongoing.