Can a Monoclonal Antibody Reduce Your Risk of Getting COVID-19?

If you’re immunocompromised, Evusheld can help with COVID-19 prevention
Monoclonal antibodies.

If you’re immunocompromised or have a weakened immune system, you’re likely still worried about catching COVID-19.

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Fortunately, a COVID-19 prevention medication does exist. More specifically, the monoclonal antibody Evusheld™ can help boost your immunity against the coronavirus and even prevent COVID-19 infection.

“Studies show Evusheld is effective against the majority of currently circulating omicron variants in the U.S., and may protect against future variants,” says infectious disease specialist Tricia Bravo, MD. “It can reduce your risk of getting COVID-19 and developing severe illness.”

As of this article being published, Evusheld remains potent against the current predominant circulating COVID-19 variants. But it may have a less neutralizing effect against some emerging variants, particularly those that have a certain mutation in one of the COVID-19 spike proteins. The U.S. Centers for Disease Control and Prevention (CDC) closely tracks all of this information, so recommendations on an Evusheld prescription may change or need to be updated in the future depending on future variants.

How do monoclonal antibodies help with COVID-19?

You have millions of antibodies circulating in your blood. These Y-shaped proteins, which are part of your immune system, fight foreign invaders, like viruses. Each antibody is programmed to target and attach themselves to a specific invader — like the virus that causes COVID-19 — and help destroy it.

“When you get sick, your body produces extra antibodies that provide immunity against a future infection,” says infectious disease specialist Andrea Pallotta, PharmD. “Vaccines produce a similar immune response — without making you sick.”

Monoclonal antibodies are manufactured antibodies that are produced in a laboratory. Just like natural antibodies, they linger in your blood looking for their target, and can add additional protection against severe disease.

Earlier in the pandemic, if you tested positive for COVID-19, you might have received an infusion of monoclonal antibodies to treat the infection. But Evusheld is different: You take it before you catch COVID-19.

Who should take monoclonal antibodies for COVID-19 prevention?

Consider taking the monoclonal antibody Evusheld to prevent COVID-19 if you are:


This means your immune system doesn’t function as it should. You can be born with a health condition that weakens your immune system. Others can develop health conditions over time. For example, the human immunodeficiency virus (HIV), if left untreated, can weaken your immune system, as can treatments for cancer, solid organ/bone marrow transplant or rheumatoid arthritis.

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Unable to receive the COVID-19 vaccine

Vaccination may not be an option if you’re allergic to the vaccine or you had a severe reaction to a previous COVID-19 shot.

How are monoclonal antibodies different from antiviral medications?

Scientists use different strategies against COVID-19. In addition to monoclonal antibodies, you may have heard of antiviral medications. Each works in a unique way, says Dr. Bravo.

“Monoclonal antibodies attach to the spike protein on the surface of the COVID-19 virus and prevent it from infecting your cells,” she explains. “Antivirals reduce how much the virus replicates in your body, which lessens illness.”

Both monoclonal antibodies and antiviral medications are available to treat people with COVID-19. Evusheld is currently the only medication that can prevent COVID-19.

What monoclonal antibodies are used for COVID-19?

The U.S. Food and Drug Administration (FDA) approved Evusheld for emergency use in December 2021. It combines two monoclonal antibodies (tixagevimab and cilgavimab) that bind to and neutralize the COVID-19 virus.

“We are still seeing people who are immunocompromised hospitalized with severe COVID-19 illness,” notes Dr. Bravo. “People who are eligible to take Evusheld aren’t always aware it’s an option. That’s why it’s so important to increase awareness of its availability, especially among those who are at highest risk for getting serious illness.”

What to expect when receiving monoclonal antibodies

When considering a new medication, it’s important to understand how it works and what to expect.

In general, monoclonal antibody medications require an injection or intravenous (IV) infusion. Evusheld involves two injections, usually in your butt or upper leg. People typically receive the injections at their healthcare provider’s office or an infusion clinic.

Other things you should know about Evusheld:

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It’s not a treatment for a COVID-19 infection

Evusheld is preventative — it’s not an approved treatment for COVID-19. To receive Evusheld, you should not have any COVID-19 symptoms. In fact, your healthcare provider may require you to have a negative COVID-19 test before receiving Evusheld. If you’ve been exposed to someone infected with COVID-19, follow current guidelines for quarantine or isolation.

You’ll need a dose every six months

Studies show the monoclonal antibodies are active for six months, so you’ll need repeat injections.

Be sure to discuss dose timing with your provider

If you’re receiving immunosuppression therapy, your healthcare provider may give you Evusheld when your immune system is weakest. This timing provides you protection when you need it most.    

Evusheld takes two weeks to reach full effectiveness

After the injection, it takes about 14 days for Evusheld to fully protect you against COVID-19.

Temporary side effects can happen

Common side effects from Evusheld include injection site reactions and dizziness. Severe reactions are very rare.

Get the COVID-19 vaccine, if you can

Evusheld is most effective in combination with the COVID-19 vaccine. If you can, get vaccinated at least two weeks before receiving Evusheld.

If you’re wondering if Evusheld could be an option for you for COVID-19 prevention, Dr. Pallotta advises talking to a trusted healthcare provider about the risks and benefits.

“Monoclonal antibodies are powerful tools in medicine,” she says. “For COVID-19, monoclonal antibodies can enhance your immunity and reduce the fear and anxiety of becoming seriously ill.”

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