On Wednesday, the U.S. Food and Drug Administration issued an emergency use authorization (EUA) for AstraZeneca’s Evusheld for the pre-exposure prophylaxis of COVID-19 in certain adults and pediatric individuals- 12 years of age and older weighing at least 40 kilograms [about 88 pounds].
Evusheld is tixagevimab co-packaged with cilgavimab and administered together.
The product is only authorized for those individuals who are not currently infected with the SARS-CoV-2 virus and who have not recently been exposed to an individual infected with SARS-CoV-2. The authorization also requires that individuals either have:
- moderate to severely compromised immune systems due to a medical condition or due to taking immunosuppressive medications or treatments and may not mount an adequate immune response to COVID-19 vaccination or;
- a history of severe adverse reactions to a COVID-19 vaccine and/or component(s) of those vaccines, therefore vaccination with an available COVID-19 vaccine, according to the approved or authorized schedule, is not recommended.
“Vaccines have proven to be the best defense available against COVID-19. 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,” said Patrizia Cavazzoni, M.D., director of the FDA’s Center for Drug Evaluation and Research. “Today’s action authorizes the use of the combination of two monoclonal antibodies to reduce the risk of developing COVID-19 in these individuals.”
One dose of Evusheld, administered as two separate consecutive intramuscular injections (one injection per monoclonal antibody, given in immediate succession), may be effective for pre-exposure prevention for six months. Evusheld is not authorized for individuals for the treatment of COVID-19 or for post-exposure prevention of COVID-19. Patients should talk with their health care provider to determine whether Evusheld is an appropriate pre-exposure prevention option for them.
Pre-exposure prevention with Evusheld is not a substitute for vaccination in individuals for whom COVID-19 vaccination is recommended. The FDA has approved one vaccine and authorized others to prevent COVID-19 and serious clinical outcomes associated with a COVID-19 infection, including hospitalization and death.
Monoclonal antibodies are laboratory-made proteins that mimic the immune system’s ability to fight off harmful pathogens such as viruses. Tixagevimab and cilgavimab are long-acting monoclonal antibodies that are specifically directed against the spike protein of SARS-CoV-2, designed to block the virus’ attachment and entry into human cells. Tixagevimab and cilgavimab bind to different, non-overlapping sites on the spike protein of the virus.