Researchers from Nantes University Hospital in France studied 117 coronavirus-naïve adults who received a donor stem cell transplant for the treatment of hematologic cancer and were given two doses of the Pfizer COVID-19 vaccine from Jan 20 to Apr 17. The median interval between the two doses was 22 days.

The study expands on a report by the same team in eJHaem on Jun 1 showing an antibody response to one vaccine dose of 55% in 112 stem cell transplant recipients.

Hematologic cancers—such as leukemia, lymphoma, and multiple myeloma—begin in blood-forming tissue, such as in the bone marrow or in immune system cells.