New Data Supports COVID-19 Booster for Blood Cancer Patients

Blood cancer patients who had at least some antibodies after the first two doses are likely to produce large amounts after the third vaccination.

Forty-three percent of blood cancer patients will produce antibodies after a third (booster) dose of the COVID-19 vaccine, according to new The Leukemia & Lymphoma Society data.

Results from the study, the largest of its kind to date, were reported December 11 at the American Society of Hematology (ASH) Annual Meeting in Atlanta.

Conversely, one in four blood cancer patients do not produce detectable antibodies after their first two doses of the COVID-19 vaccine, LLS said in a press release.

The data, based on the LLS National Patient Registry, which has been tracking COVID-19 vaccine response among more than 11,000 blood cancer patients since February 2021, also showed that blood cancer patients who had at least some antibodies after the first two doses are likely to produce large amounts after the third vaccination.

In fact, for some patients with blood cancer, the third dose led to antibody levels seen in healthy adults, the LLS said.

“But blood cancer patients also need to remember that they are among the nearly three million Americans with weakened immune systems who may not get optimal vaccine protection. We encourage blood cancer patients to continue to layer on additional precautions, such as mask wearing and social distancing,” Nichols added.

“Our data shows a clear benefit of giving blood cancer patients three primary vaccine doses, but there is still a large portion of patients who will remain at risk even with the additional dose,” says Lee Greenberger, Ph.D., chief scientific officer for LLS.

LLS previously reported findings from first and second dose vaccination, as well as a smaller study with third vaccination in near real-time. The larger pool of data in the current study — 699 patients — provides “more robust information about how the third COVID-19 mRNA dose works in patients with all types of blood cancer,” LLS said.

The study was weighted to include more patients with blood cancers that deplete the immune system’s B-cells, which are responsible for making antibodies. Patients with these types of cancer, including chronic lymphocytic leukemia, diffuse large B-cell lymphomas, follicular lymphomas, marginal zone lymphomas, mantle cell lymphomas, and Waldenstrom’s Macroglobulinemia, are less likely to develop antibodies, LLS said.

In contrast, the remaining participants had myeloid forms of leukemia, Hodgkin’s lymphoma and multiple myeloma, all of which tend to respond more favorably to initial vaccinations, as well as the third vaccination. Detectable antibody rates in these patients ranged from 75% to 100%.