The anti-CD47 antibody magrolimab with obinutuzumab and venetoclax in relapsed or refractory indolent B-cell lymphomas.

Follicular lymphoma (FL), marginal zone lymphoma (MZL), chronic lymphocytic leukaemia (CLL) and mantle cell lymphoma (MCL) are characterized by a continuous incidence of relapse and increasing resistance to therapy. Novel immunotherapy approaches are needed. Magrolimab, a CD47-blocking antibody, disrupts CD47:SIRPα-mediated antiphagocytic signalling. When combined with a prophagocytic signal from an anti-CD20 antibody rituximab, it has shown activity in relapsed or refractory FL and MZL. In this phase 1 study, adding the BCL2-inhibitor venetoclax to magrolimab and the anti-CD20 antibody obinutuzumab resulted in complete responses in 6 of 10 (60%) evaluable patients with FL, MZL or CLL. Notably, we did not observe increased risk of infections previously reported from studies of magrolimab in acute myeloid leukaemia and higher risk myelodysplastic syndromes.