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People with cancer are often given immunosuppressive treatments that weaken their innate immune defenses. This puts them at high risk of severe disease, should they become infected by COVID-19.
But a study conducted by MedUni Vienna has now shown that many of these patients can build up sufficient immunity against the coronavirus after the third vaccination, or booster shot. The results were recently published in the journal European Journal of Cancer.
If cancer patients become infected, they are not only susceptible to developing severe COVID-19 but also risk interruptions to their cancer treatment or monitoring. Because of this, COVID-19 vaccination is recommended for all cancer patients, as is a third booster vaccination, given that immunity wanes over time, the findings showed.
The analysis showed a decrease in antibody levels between three and six months after the second vaccination in patients with solid tumors and those with hematological malignancies not receiving anti-B-cell therapies. The cancer patients’ antibody levels rose again following the third booster dose, and although the new antibody levels were not as high as in the healthy control group, they were probably still good enough to provide protection, according to researchers.
WHAT’S THE IMPACT
The results could inform ground-level care at hospitals and health systems as clinical staff struggle to keep up with routine patient care during a relentless pandemic that has strained resources and stretched staff and margins.
Not all of the findings were encouraging, however. Patients with haematologic cancers such as leukemia or lymphoma are often given CD20-depleting therapy, which inhibits the very cells responsible for developing the necessary antibodies. In such cases, even the third vaccination failed to bring about the desired immune response.
Such patients, who are unlikely to be able to build up adequate protection, are at risk and have to be especially careful when it comes to social contacts and be rigorous in observing the appropriate hygiene measures, authors said.
Drugs that inhibit viral replication or the intravenous administration of engineered antibodies may be considered as a possible strategy to improve COVID-19 protection in patients who cannot mount an adequate vaccine response, but more data is needed to confirm this.
The most common side effects after the third dose were localized pain (46.9%), fatigue (15.6%), and fever/chills (10.0%) – similar to those experienced by people who do not have cancer.
THE LARGER TREND
In January, the U.S. Food and Drug Administration authorized Pfizer-BioNTech’s COVID-19 booster shots for children 12 to 15 years old.
Additionally, the FDA shortened the time between the completion of primary vaccination of the Pfizer offering and a booster dose to at least five months. The new guidance also allows for a third primary series dose for certain immunocompromised children 5 through 11 years old.
The agency determined that the protective health benefits of a single booster dose of the Pfizer shot outweigh the potential risks in those who fall under that age group. The boosters, according to the FDA, provide continued protection against COVID-19 and the associated consequences that may occur, such as hospitalization and death.
Days later, New York Governor Kathy Hochul said healthcare workers would be required to get a booster shot.