Coronavirus vaccine less effective on leukemia patients – Israeli study
The response was lowest among patients who were in the process of receiving treatment, with only 16% of them developing antibodies.
By ROSSELLA TERCATINA healthcare worker shows an ampule with the Sputnik V coronavirus disease (COVID-19) vaccine in Podgorica, Montenegro, February 22, 2021.(photo credit: REUTERS)
The coronavirus vaccine is less effective in stimulating the production of antibodies in patients affected by chronic lymphocytic leukemia (CLL), a study led by researchers from Tel Aviv University and Tel Aviv Sourasky Medical Center has shown.“This leukemia is the most common in the Western world and is associated with an immune deficiency which can be caused by the disease itself or by the treatment,” said Prof. Yair Herishanu, director at the research laboratory for CLL cell biology at Sourasky, and the lead author of the study that appeared in the medical journal Blood, published by The American Society of Hematology.“We knew that these patients often do not react well to other vaccines in terms of the number of antibodies they produce, so it was important for us to test what happens with the coronavirus vaccine,” he added.CLL patients are considered at high risk of developing serious symptoms if they contract COVID and mortality among them has been higher than in the general population.Some 167 CLL patients participated in the study, and 52 of them were matched with 52 healthy individuals of the same sex and age who acted as a control group. All patients were inoculated with the Pfizer mRNA vaccine.“We measured the level of antibodies two to three weeks after the second shot, and we found that only 40% of the participants had developed them,” Herishanu explained.The ability to produce antibodies varied depending on the clinical situation of the CLL patients.The response was lowest among patients who were in the process of receiving treatment, with only 16% of them developing antibodies.Among those who were sick and were not receiving treatment – as with this type of leukemia some patients are monitored and received treatment only upon progression – some 55% developed antibodies, while almost 80% of those in remission did.“It is important to remember that the protection offered by the vaccine does not depend only on the antibodies, but also on the cellular response,” Herishanu pointed out. “For this reason, we cannot state that the vaccine did not offer any protection for those who did not develop antibodies, but for sure the protection is not optimal.”The professor emphasized that it is essential for CLL patients to continue to wear masks and be careful also after being jabbed.“For the future, it is going to be critical to see whether an additional shot of the vaccine can help,” Herishanu concluded. “We are already looking into it.”
