FDA Grants Emergency Authorization for COVID Prevention Drug for the Immunocompromised

The Food and Drug Administration (FDA) has authorized the use of a non-vaccine therapy to prevent COVID-19 infections in immunocompromised people.

The FDA granted emergency use authorization for AstraZeneca's Evusheld, a combination therapy of the human monoclonal antibodies tixagevimab and cilgavimab, on Wednesday. The therapy was approved only for people with conditions that prevent them from mounting an adequate immune response from vaccination or in those who cannot be vaccinated due to a proven record of severe reactions to COVID-19 vaccines or components of the vaccines.

COVID-19 Preventative Drug Authorization AstraZeneca Monoclonal Antibodies
The Food and Drug Administration issued an emergency use authorization for AstraZeneca’s Evusheld on Wednesday. The AstraZeneca logo is pictured with a syringe in the forefront in this picture taken on November 17, 2020. JUSTIN TALLIS/AFP/Getty

"Vaccines have proven to be the best defense available against COVID-19," Dr. Patrizia Cavazzoni, director of the FDA's Center for Drug Evaluation and Research, said in a statement. "However, there are certain immune-compromised individuals who may not mount an adequate immune response to COVID-19 vaccination, or those who have a history of severe adverse reactions to a COVID-19 vaccine and therefore cannot receive one and need an alternative prevention option."

"Today's action authorizes the use of the combination of two monoclonal antibodies to reduce the risk of developing COVID-19 in these individuals," added Cavazzoni.

Evusheld is administered as two intramuscular injections, given in immediate succession, and may be effective at preventing COVID-19 infections for up to six months. The trial that formed the basis of the therapy's authorization found that it was 83 percent effective in preventing infections among mostly high-risk participants.

"This is a monumental moment for patients looking for an added layer of protection against COVID-19 on top of vaccination," Ruud Dobber, Ph.D., Executive Vice President and President of the BioPharmaceuticals Business Unit at AstraZeneca, said in a statement obtained by Newsweek. "We are committed in our fight against COVID-19 to ensure as many people as possible are protected, and now we can offer this additional option for the more vulnerable populations."

Conditions that can lead to inadequate immune response from vaccination include cancer, HIV infections and other diseases that compromise the immune system, being an organ or stem cell transfer recipient and being treated with high-dose corticosteroids. The number of people who would qualify for Evusheld based on severe reactions to COVID-19 vaccines is likely to be far fewer since such reactions have been exceedingly rare, despite anti-vaccine activists sharing contradictory memes based on misinterpreted data.

The FDA stressed that "Evusheld is not a substitute for vaccination in individuals for whom COVID-19 vaccination is recommended," urging those who are able to be vaccinated to do so as soon as possible. Data recently analyzed amid the emergence of the Omicron variant have indicated that existing vaccines continue to offer protection, although booster shots have been recommended in those who were vaccinated over six months ago.

A separate trial of Evusheld found that the therapy was 88 percent effective as a treatment preventing severe illness or death when given within three days of the onset of COVID-19 symptoms. However, the FDA only authorized the therapy for preventative use in the immunocompromised on Wednesday. An additional trial to test Evusheld as a treatment for hospitalized patients is ongoing.