New AstraZeneca COVID prevention drug won’t replace vaccine

key takeaways

  • A newly licensed monoclonal antibody called Evusheld may help prevent COVID-19 in people who cannot be vaccinated.
  • However, this new treatment is not a substitute for vaccination for anyone who can safely get it.
  • Receiving an authorized or approved vaccine, and when eligible, a booster dose, is the best way to protect yourself from the new coronavirus.

AstraZeneca’s Evusheld isn’t the first U.S. Food and Drug Administration (FDA) to authorize a monoclonal antibody therapy to fight COVID-19, but it is the first Medicines specifically authorized to prevent some people from getting COVID in the first place.

The FDA said in December that Evusheld could reduce a person’s chance of contracting COVID-19 by 77 percent. Early data also suggest that this treatment may be protective against the Omicron variant.

What are monoclonal antibodies?

According to the FDA, “Monoclonal antibodies are laboratory-made proteins that mimic the ability of the immune system to fight off harmful pathogens such as viruses.”

However, experts want people to understand that preventive treatments like Evusheld are no substitute for someone who can be safely vaccinated.

What is Evusheld?

Evusheld is a combination of two monoclonal antibodies — tixagevimab and cilgavimab — designed to target the spike protein of the SARS-CoV-2 virus. This in turn prevents the virus from entering human cells. The drug is given in two injections, one after the other.

Stuart Ray, MD, professor of medicine at Johns Hopkins Medicine, told VigorTip that the protection offered by treatments like Evusheld is a form of “passive immunity” that is less durable than the protection offered by vaccines.

Recent data suggest more COVID-19 patients will benefit from monoclonal antibody therapy

Who does Evusheld serve?

The FDA’s authorization states that Evusheld is only for people who are not currently infected with COVID and who have not had recent close contact with an infected person.

Additionally, Evusheld recipients must:

  • Moderately to severely compromised immune system due to a medical condition or taking immunosuppressive drugs (such as post-transplant anti-organ rejection drugs and certain types of chemotherapy), or
  • History of serious adverse reactions to COVID-19 vaccines or components of COVID-19 vaccines

How does Evusheld compare to vaccination?

COVID vaccination is safe and effective. Experts want to make sure people understand that Evusheld and other similar treatments aren’t designed to replace vaccines for most people.

“If you’re still not vaccinated against COVID-19, your best protection is to get a full vaccine dose and booster,” William Schaffner, a professor of medicine at Vanderbilt University School of Medicine, told VigorTip.

Monoclonal Antibodies and the COVID Vaccine

If you have been exposed to monoclonal antibodies, they can help you prevent COVID; if you are infected, monoclonal antibodies can help you avoid serious illness because they strengthen your immune system.

Vaccines train and prepare your immune system so that if you are exposed to a virus, your body recognizes it and knows how to fight it.

While monoclonal antibody treatments work as soon as you get them, they only last for weeks to months.

The vaccine’s protection starts to kick in about 2 weeks after your last dose. While we’re not sure exactly how long each COVID vaccine will protect you, most will work for at least a few months, and boosters may provide greater protection (and last longer).

Schaffner said that while Evusheld did Antibodies are given to help prevent COVID and must be given again every 6 months. On the other hand, the protection you get from the COVID vaccine may last longer.

It’s critical that your body’s antibody response protects you from COVID-19. Current vaccines also provide other important immune responses, including T- and B-cell activation, but Evusheld does not, Schaffner said.

The information in this article is current as of the date listed, which means that you may have updated information as you read this article. For the latest updates on COVID-19, visit our Coronavirus news page.

what does this mean to you

Evusheld is a new preventive COVID-19 treatment for people who cannot develop an adequate immune response to COVID through vaccination alone or who may be at risk from taking the vaccine.

As with other monoclonal antibody treatments, experts want people to understand that Evusheld is not a substitute for vaccination in people who can be safely vaccinated.

Should you be concerned about waning COVID-19 antibodies?