COVID-19 treatment options for cancer patients: 7 things to know
Last updated on Aug. 9, 2022.
When the COVID-19 pandemic began two years ago, so little was known about the SARS-CoV-2 virus that all anyone could do was treat the symptoms.
Today, however, several options are available to treat COVID-19 and fight the underlying virus that causes it. But which ones are best for cancer patients? How do they work? And are some more effective than others?
What treatments are available for cancer patients right now that specifically target COVID-19?
For hospitalized cancer patients with COVID-19 infections, the main drug we use is called remdesivir (Veklury). It’s an antiviral that’s administered through an IV.
Very ill or high-risk patients could receive remdesivir for up to 10 days. But most will receive it between 5 and 10. Patients who have minimal symptoms and are not at high risk for severe illness could receive it for as few as 3 days. But they would still benefit from it. Remdesivir has been shown to be effective against the coronavirus in many studies, and we’ve had access to it for more than a year.
Steroids have also proven beneficial to some hospitalized patients with COVID-19 who require high levels of oxygen or are on breathing machines. Though they don’t specifically target the virus, steroids can block or reduce the inflammatory responses of SARS-CoV-2 in the lungs.
What about COVID-positive cancer patients who aren’t hospitalized?
For outpatients with COVID-19, we may use two oral drugs to help them avoid being hospitalized. They are:
molnupiravir (from Merck)
Paxlovid (from Pfizer)
Both are antiviral pills that are taken by mouth, but supplies are very limited.
How do these antiviral medications work?
They all work slightly differently to prevent the virus from replicating itself. Some bind to a specific viral enzyme (RNA-dependent RNA polymerase) and terminate RNA transcription prematurely (remdesivir). Some introduce errors into the SARS-CoV-2 virus’ genetic code (molnupiravir). And some inhibit the function of a particular SARS CoV-2 protein (paxlovid).
What about monoclonal antibodies? How do those work? And are they effective against COVID-19?
COVID-19 monoclonal antibodies target the spike protein of SARS-CoV-2 and are designed to block the virus’ ability to attach to and enter human cells.
Several different monoclonal antibodies (mAbs) had been granted Emergency Use Authorization (EUA) by the Food and Drug Administration (FDA) and were used to prevent hospitalization but most have had their EUAs revoked due to a lack of activity against newer COVID-19 variants. A list of past and present mAbs can be seen below:
bamlanivimab and etesevimab (made by Eli Lilly) – no longer recommended
casirivimab and imdevimab (made by Regeneron) – no longer recommended
sotrovimab (made by GlaxoSmithKline/Vir) – no longer recommended
bebtelovimab (made by Eli Lilly) – retains its EUA and remains active against currently prevalent omicron variants
Under EUA rules, mAbs cannot be used in hospitalized patients or patients who require oxygen. They can only be used in outpatients with mild to moderate COVID-19 who are at high risk of progression to a more severe illness.
Unfortunately, only one of these monoclonal antibodies, bebtelovimab, has proven effective in a lab setting against many omicron variants and its supply is limited. The previous mAbs were helpful against earlier variants like delta, but they’re not as effective against omicron due to changes in the spike proteins of the virus. Therefore, the FDA has revoked the EUA for the older mAbs and no longer recommends them as COVID-19 therapy.
Is there anything available that can prevent cancer patients from contracting COVID-19?
Getting a COVID-19 vaccine is still the best way to prevent infection. But for patients who are too sick to get vaccinated or too immunocompromised to benefit much from vaccination, there may be an alternative.
AstraZeneca manufactures some monoclonal antibodies now called Evusheld, which is a combination of cilgavimab and tixagevimab. It has demonstrated some limited efficacy against omicron and was granted EUA status by the FDA, so it could be used for “pre-exposure” in some high-risk cancer patients. It is not authorized for treatment or post-exposure prophylaxis, and patients must meet specific criteria outlined by the FDA to be eligible for Evusheld.
How can patients obtain these medications?
Supply of these drugs varies, and they have very strict eligibility guidelines.
At a bare minimum, for instance, to qualify for Paxlovid, cancer patients must:
have a confirmed case of COVID-19
have only a mild to moderate infection
be at high risk of being hospitalized
have had symptoms for no longer than 5 days
be age 12 or older
weigh at least 40 kg (88 lbs.)
So, while there are options, certain patients may not qualify for certain therapies based on the strict criteria. Supply may also be limited to certain pharmacies and physicians must answer many questions about their patients to ensure compliance with the FDA EUA before these agents can be prescribed. So, it’s very important to stay flexible if you approach your doctor about any of these therapies. They will work to determine if you qualify for any of the agents and, if you do, which agent is the most appropriate for you specifically.
Anything else cancer patients should know about possible COVID-19 treatments?
If you’re currently receiving chemotherapy as a part of your cancer treatment, it could be delayed if you’re very sick with COVID-19, especially if you have pneumonia.
Also, every drug has potential side effects. And since one of these antiviral medications is a combination of two agents (Paxlovid), the chances of them interacting with other drugs you’re taking are higher.