Preventing and Treating COVID-19 in Cancer Patients: Challenges in the Omicron Era

Additional Protective Measures, Emerging Challenges

Patients should “continue to follow nonpharmacological behavioral preventative measures, including avoiding crowds, masking in public, social distancing, and hand hygiene,” advised Sherif Mossad, MD, an infectious disease specialist at Cleveland Clinic and associate professor in the Cleveland Clinic Lerner College of Medicine of Case Western Reserve University in Ohio. 

Dr Mossad also noted the importance of at-home testing using COVID-19 rapid antigen detection tests. Patients should self-test if they develop COVID-19 symptoms, and a positive test should prompt contact with their health care provider. Symptomatic patients who test negative should pursue PCR testing. 

Close contacts of cancer patients should follow these measures as well and stay up to date with vaccinations to create a “circle of protection” around patients, Dr Mossad said. 

With the newer variants, the “virus binds more strongly to our cells and has mutations that allow it to escape the immune response,” said Jim Boonyaratanakornkit, MD, PhD, an infectious disease specialist and researcher at the Fred Hutchinson Cancer Center in Seattle, Washington. The greater transmissibility of these variants underscores the importance of preventive measures, he added.  

“While we don’t have a single ‘magic bullet’ for prevention and protection for our patients, the combination of vaccination, masking, and testing is the best way to optimize protection using all the tools available,” Dr Sherman said.  

Unfortunately, these tools are becoming more difficult for cancer patients and the general public to use as the pandemic wears on. Though anecdotal reports suggest cancer patients tend to wear masks and would like others to wear masks around them, mask mandates are largely a thing of the past, even in some health care settings.^17-21 

Another potential barrier to protecting patients from COVID-19 is the impending end of the public health emergency, which will take place on May 11.²² Although COVID-19 vaccines will remain available and Moderna’s vaccines will remain free, Pfizer is planning to charge for its COVID-19 vaccines.²³

The end of the public health emergency also means that patients with Medicare will no longer receive free at-home COVID-19 tests.²⁴ Some patients with private insurance may have access to free at-home tests, but others may not. Likewise, COVID-19 tests ordered or given by health care professionals may or may not be free after the public health emergency ends.

One method of COVID-19 prevention that was found to be effective for cancer patients but is no longer an option is tixagevimab-cilgavimab (Evusheld).^25-27 The US Food and Drug Administration (FDA) recently withdrew the emergency use authorization (EUA) for Evusheld when it was shown to be ineffective against more than 90% of the omicron subvariants circulating in the United States at the time. 

Changes to COVID-19 Treatment, Remaining Options 

Like the case with Evusheld, many mAbs that were previously authorized for COVID-19 treatment are no longer authorized for use because they are not active against currently circulating variants, Dr Hochman said. 

Over the course of the pandemic, the FDA has revoked EUAs for several mAbs once used to treat COVID-19, including bamlanivimab-etesevimab, casirivimab-imdevimab (REGEN-COV), bamlanivimab alone, sotrovimab, and bebtelovimab.^28-33 

However, there are a few antiviral therapies that are expected to remain active against the dominant subvariants of SARS-CoV-2 when administered early in the course of illness. These include nirmatrelvir-ritonavir (Paxlovid), remdesivir, and molnupiravir.³⁴ 

“Paxlovid is the preferred treatment for most outpatients, or remdesivir if Paxlovid is contraindicated, and the oral antiviral molnupiravir is authorized as an alternative when Paxlovid and remdesivir are not accessible or clinically appropriate,” Dr Tam said.³⁵  

Due to the potential for severe drug-drug interactions with Paxlovid, particularly with certain immunosuppressant medications, close monitoring and dose adjustments may be needed when initiating Paxlovid, Dr Tam noted.

“I always confer with a pharmacist first to ensure that Paxlovid won’t have any drug-drug interactions with the medications my patients are already on,” said Rahul Banerjee, MD, an assistant professor in medical oncology at the University of Washington and the Fred Hutchinson Cancer Center in Seattle.

Dr Hochman explained that while molnupiravir does not carry the risk of drug-drug interactions associated with Paxlovid, it does “pose a theoretical risk of being incorporated into host DNA, leading to mutations,” and thus is contraindicated for use in pregnant patients or for “men of reproductive potential who are sexually active with women of childbearing potential for the duration of treatment and for 3 months after completing treatment, unless they use a reliable method of contraception.”³⁶ 

Dr Mossad also noted that clinicians should be aware of the risk for rebound symptoms in patients treated with Paxlovid or molnupiravir.^37,38 

For patients who are hospitalized for COVID-19 but don’t require oxygen, remdesivir is recommended.³⁹ For hospitalized patients who require conventional oxygen, options include remdesivir plus dexamethasone, baricitinib, and tocilizumab. Baricitinib and tocilizumab can be combined with dexamethasone in patients who require high-flow nasal cannula oxygen, noninvasive ventilation, mechanical ventilation, or extracorporeal membrane oxygenation.

COVID-19 convalescent plasma, in the outpatient or inpatient setting, is an additional option for patients who have immunosuppressive disease or are receiving immunosuppressive treatment.⁴⁰ 

For pediatric cancer patients, treatment strategies are limited, said Diego Hijano, MD, assistant faculty member in the department of infectious diseases at St. Jude Children’s Research Hospital in Memphis, Tennessee. 

Paxlovid can be used to treat mild to moderate COVID-19 in nonhospitalized patients who are 12 years or older, weigh at least 40 kg, and are at high risk of progression to severe COVID-19.⁴¹

However, for children under 12 years of age who are high risk and have mild-to-moderate COVID-19 symptoms, remdesivir is the only available treatment that can be used to prevent severe disease, Dr Hijano said. 

For children who already have severe COVID-19, remdesivir, dexamethasone, baracitinib, tofacitinib, and tocalizumab are options.⁴² 

“For patients who have moderate to severe disease requiring hospitalization and supplemental oxygen, we use remdesivir and dexamethasone,” Dr Hijano noted. “For patients who can’t receive steroids or have a lack of response in the first 24 hours, we consider the use of baricitinib.” 

This article originally appeared on Cancer Therapy Advisor