New Approval for Diffuse Large B-Cell Lymphoma Treatment: Tafasitamab-cxix

On July 31, 2020, the US Food and Drug Administration (FDA) granted accelerated approval to tafasitamab-cxix (MONJUVI, MorphoSys US Inc.), a CD19-targeting cytolytic antibody used with lenalidomib, for adults diagnosed with relapsed or treatment-refractory diffuse large B-cell lymphoma. The patient group was specified as diffuse large B-cell lymphoma arising from low-grade lymphoma in patients who are ineligible for autologous stem-cell transplantation (using stem cells collected from the same person). This specifies the diffuse large B-cell lymphoma population for whom the treatment is intended.

The efficacy of tafasitamab-cxix with lenalidomide was evaluated in a multicenter study involving 81 patients. Patients received intravenous tafasitamab-cxix and lenalidomide for a maximum of 12 cycles, followed by tafasitamab-cxix monotherapy.

The researchers observed, in 71 patients diagnosed with diffuse large B-cell lymphoma, a best overall response rate of 55%, with patients showing complete responses in 37% and partial responses in 18%. The median duration of response was reported as 21.7 months. The most common adverse effects (≥%20) were neutropenia, fatigue, anemia, diarrhea, a decrease in the blood platelet count (thrombocytopenia), cough, an excessive rise in body temperature (pyrexia), peripheral edema, respiratory tract infection and decreased appetite.

Approval was granted based on the treatment response rate obtained with tafasitamab-cxix. Continued approval for this treatment option may depend on the confirmation and description of clinical benefit in further studies.

The FDA granted tafasitamab-cxix orphan drug designation, breakthrough therapy designation, fast track and priority review status. “Orphan Drug Status” is an FDA program supporting drugs developed to treat relatively rare diseases affecting fewer than 200 thousand people annually in the United States.