Pfizer, Moderna COVID vaccines evoke delayed response in blood cancer patients: Study

mRNA based Moderna and Pfizer/BioNTech vaccines are highly effective against preventing severe coronavirus infections or death but evoke a lower and delayed response in patients with blood cancer, a recent study has found. Published in Cell, it has therefore raised the need to continuously monitor or follow precautions in patients with myeloma- a type of blood cancer. The study was conducted by a team of researchers from Icahn School of Medicine at Mount Sinai Health System, New York.

For the purpose of research, the team analyzed the antibody levels of 320 multiple myeloma patients, 260 of whom received two doses of COVID-19 vaccinations. In the aftermath, they found that 15.8 per cent had undetectable antibodies. Repeated antibody measurements from before the patient's vaccination to 60 days after the second dose also shows significantly delayed or suboptimal responses, particularly in patients who have not contracted COVID-19.

"This study underscores the need for routine blood tests on multiple myeloma patients after vaccination to understand their risk and the potential need to continue wearing masks and socially distance until the pandemic wanes," said Samir Parekh, Professor of Medicine (Hematology and Medical Oncology), and Oncological Sciences, at Mount Sinai.

"This also calls for clinical trials to study the use of prophylactic therapies, like monoclonal antibodies, to mitigate Covid-19 risk or to use different vaccines or booster vaccinations in these patients," he added.

As per the team, the results of the study may be generalized to other cancer or immunocompromised patients. It is imperative to note that the team only used mRNA based vaccines for the research.

What are mRNA based vaccines?

Pfizer/BioNTech and Moderna have developed an entirely new type of vaccine based on mRNA [Messenger RNA vaccines] to combat the coronavirus. A UK-based university, with the help of a two-minute-long video, has explained how the mRNA vaccine targets the immune system to eliminate COVID-19. The coronavirus vaccines, when injected into the upper arm sends the mRNA into the bloodstream. The virus makes copies of itself by entering into the healthy host cells using protein spike structures that are made out of RNA and DNA. The mRNA from the vaccine contains the synthetic version of the RNA that tricks the immune system that the virus is present, thereby accelerating the anti-body-making process. 

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