Cancer and COVID-19: What protection do antiviral therapies provide?

Last updated Jan. 31, 2023

If you or someone you know has had COVID-19 recently, you may have heard of PAXLOVID. Maybe you’ve even heard about a so-called COVID-19 rebound in people who’ve taken this antiviral therapy.

So, what is PAXLOVID and why does the Centers for Disease Control and Prevention (CDC) recommend it for people who are immunocompromised? We asked Chief Infection Control Officer Roy Chemaly, M.D., what patients with cancer need to know about the antiviral treatment for COVID-19.

What is PAXLOVID, and who can receive it?

PAXLOVID is the brand name for a combination antiviral medication that can lessen symptoms in patients who have mild or moderate COVID-19. It is intended for those who are in the early stages of infection and are at risk of getting severely worse.

Patients with cancer are eligible to receive PAXLOVID with a prescription from their doctor and they will need to start it within 5 days of the onset of their COVID-19 symptoms. If you are in the hospital, more aggressive therapy may be needed to help you fight the infection.

How does PAXLOVID work to fight an infection?

PAXLOVID contains nirmatrelvir, which works to inhibit the SARS-CoV-2 virus from replicating in the body. It also contains ritonavir, which boosts the effects of nirmatrelvir, helping it work better. The combination of these antiviral medications helps reduce the risk of hospitalization for people who have mild-to-moderate COVID-19.

What are the side effects of PAXLOVID?

Some people report having a metallic or otherwise altered taste in their mouth when taking PAXLOVID. Your doctor also should consider the health of your kidneys and liver before prescribing it. For most people, reported side effects have been mild.

If you have cancer, your doctor will consider all of the medications you are taking to ensure there are no interactions between medicines used to treat COVID-19 (such as PAXLOVID or dexamethasone) and cancer-related therapies like prophylactic antimicrobials and other medicines.

Why do some people need a second round of PAXLOVID treatment?

PAXLOVID is the first oral antiviral medication to be authorized for emergency use by the Food and Drug Administration (FDA) for the treatment of COVID-19. That makes it an investigational medication. Your doctor may prescribe it based on your COVID-19 symptoms and response to the medication.

Some people experience a relapse of COVID-19 – sometimes called a COVID-19 rebound – even after taking an entire course of PAXLOVID. For instance, after Dr. Anthony Fauci tested positive for COVID-19, he received two courses of PAXLOVID to help him stay out of the hospital.

What else can I do to protect myself?

Vaccination should be considered the first line of prevention against COVID-19. However, some patients with cancer may be unable to mount a protective response with COVID-19 vaccines and remain at risk for severe COVID-19 should they become infected.

For people who are eligible to receive it, PAXLOVID should be a treatment option they discuss with their doctor.

Schedule your COVID-19 vaccine or booster at MD Anderson.

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