Patients with certain blood cancers may be at risk for breakthrough COVID-19 infections
Approximately one-quarter of patients with hematologic malignancies did not produce measurable antibodies after two doses of COVID-19 vaccines, according to a study from The Leukemia & Lymphoma Society published in Cancer Cell.
Results varied depending on blood cancer type. Patients with non-Hodgkin lymphoma appeared least likely to develop antibody protection, and patients with multiple myeloma had the highest level of antibodies following vaccination.
“Patients who fail to make antibodies in response to the SARS-CoV-2 vaccines may be vulnerable to COVID-19 breakthrough infections and need to continue taking precautions to avoid exposure to COVID-19,” Lee S. Greenberger, PhD, chief scientific officer at The Leukemia & Lymphoma Society (LLS), told Healio. “LLS encourages [patients with blood cancer] to get vaccinated but act unvaccinated by maintaining recommended preventive measures like wearing a mask, social distancing, handwashing, and avoiding crowds and poorly ventilated indoor spaces, even after vaccination.”
Greenberger called the magnitude of the effect —a 25% seronegative rate — “surprisingly high,” putting thousands of patients with blood cancer at risk for future infections.
Greenberger and colleagues at LLS studied serologic response to the COVID-19 messenger RNA vaccines among 1,445 patients (median age, 66 years; range, 16-100; 95.2% white; 60.1% women) with lymphoma, leukemia and myeloma.
Between March 12 and May 5, they evaluated the anti-SARS-CoV-2 spike protein (S) antibody response after a full course (two doses) of the BNT162b2 (Pfizer/BioNTech, n = 793) and mRNA-1273 (Moderna, n = 652) vaccines at least 14 days after the second dose.
Researchers reported the proportion of patients who developed a positive antibody response to the anti-S antibody with point estimates, and they calculated CIs with the Wilson method.
About 75% of patients produced antibodies to the SARS-CoV-2 mRNA vaccines.
Within B cell malignancies, researchers observed seronegativity in nearly all non-Hodgkin lymphoma subtypes studied, including among patients with mantle cell lymphoma (56%), marginal zone lymphoma (38%), chronic lymphocytic lymphoma (36%), Waldenström’s macroglobulinemia (26%), follicular lymphoma (22%) and diffuse large B cell lymphoma (21%). Conversely, all but one of the 64 patients with Hodgkin lymphoma demonstrated seropositivity.
Greenberger and colleagues observed low rates of seronegativity among patients with acute lymphocytic leukemia (12%), acute myeloid leukemia (9%) and chronic myeloid leukemia (2.9%), as well as among those with multiple myeloma (5.3%) and smoldering multiple myeloma (0%).
“Patients need to consult their physicians and certainly contact their physicians should they suspect COVID-19 infections,” Greenberger told Healio. “Early treatment, especially with monoclonal antibodies to SARS-CoV-2, may reduce the chances of serious complications due to COVID-19 infections.”
In a further effort to understand the entire immune response to vaccines, LLS researchers have embarked on a study of T-cell responses to vaccination, according to Greenberger.
“U.S. and (United Kingdom) academic investigators ... are also attempting to understand if the antibodies produced in blood cancer can neutralize SARS-CoV-2, including the delta variant,” he said. “In the long run, LLS is supporting work to develop alternative immunological strategies to activate the immune system to avoid future infections in [patients with blood cancer]. We are currently lobbying for clinical trials that will look at the benefit of booster shots in patients who fail to make sufficient antibodies.”
For more information:
Lee M. Greenberger, PhD, can be reached at The Leukemia & Lymphoma Society National Office, 3 International Drive, #200, Rye Brook, NY, 10573; email: firstname.lastname@example.org.