AstraZeneca Antibody Cocktail Fails To Prevent Covid Symptom
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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 outcome is a blow to 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. 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. The Astra medicine attracted interest even before it could prove its efficacy.

~ Some Promise

All the trial participants had been exposed to a person with Covid-19 in the past eight days. The drug Covid-19 had some preventive effect on those who became infected up to a week after taking the antibody. All participants had a negative antibody test when dosed to exclude prior infection. The results suggest the cocktail may be useful in preventing symptomatic Covid-19 in individuals not already infected, said lead researcher.

~ New Variants

Antibody drugs are viewed as a way to protect people such as cancer patients whose immune systems may not respond as well to vaccines. They may provide much-needed treatments as countries encounter new variants and waves of infections. But the products are cumbersome to use and scale-up is limited. Unlike vaccines, where billions of doses can be manufactured every year, antibody treatments can only reach several million.

The Astra trial, named Storm Chaser, is one of six advanced-stage studies the drugmaker is running to test its medicine. Glaxo and Vir Biotechnology Inc. received U.S. emergency-use authorization for their product last month after it showed it could kept at-risk patients from worsening. Eli Lilly & Co.'s authorization for an antibody treatment was revoked in April amid questions over its effectiveness.