Prior rituximab administration is associated with reduced rate of acute GVHD after in vivo T-cell depleted transplantation in lymphoma patients.

Rituximab is one of the most commonly used drugs in the treatment of B-cell non-Hodgkin lymphoma. Because of its ability to target CD20(+) lymphocytes, its use before allogeneic stem cell transplantation seemed to reduce risk of graft-vs.-host disease (GVHD) occurrence. We retrospectively analyzed the outcomes of adult patients diagnosed with CD20(+) lymphoproliferative disease undergoing allogeneic stem cell transplantation and receiving, or not receiving, rituximab up to 3 months before transplantation. Analysis on a cohort of 57 patients showed a protective role of rituximab on the occurrence of acute GVHD for those receiving anti-thymocyte globulin during conditioning (n = 39). Grade 2 to 4 and 3 to 4 acute GVHD occurred in 10% vs. 48% (p = 0.03) and 0% vs. 24% (p = 0.08) in the rituximab and no-rituximab groups, respectively. No impact on chronic GVHD was observed. These results confirm a protective role of rituximab on the occurrence of GVHD and enhance further investigation on future studies aimed at reducing GVHD incidence.