A Phase 2 Study of 90Y-Zevammab in Relapsed Refractory Non-Hodgkin's Lymphoma: Preliminary Report of the Argentinean Cooperative Group
The purpose of this prospective study was to address the efficacy of Yttrium ibritumomab tiuxetan (Zevalin) in patients with relapsed or refractory lymphomas who had already failed rituximab. Rituximab is a monocloncal antibody that targets CD20, which is found on the surface of lymphoma cells. Zevalin is rituximab with the addition of a radioactive molecule. The drug takes the radiation directly to the lymphoma cells, destroying it, but sparing the healthy tissues.
Twenty seven patients were enrolled, 22 with follicular lymphoma and 5 with Mantle cell lymphoma. All had previous treatments and five of the patients had previously undergone bone marrow transplant.
Tumor response was evaluated at 3 and 6 months after treatment. Fifteen patients responded to treatment, with eleven having a complete response and four having a partial response. Ten of eleven patients remained in remission for between 3 to 15 months. Toxicities were mostly related to myelosuppression (decreases in blood counts) and were treated with transfusions and growth factors. There was one treatment related death. There was a 41% complete response rate after treatment with Yttrium ibritumomab tiuxetan (Zevalin) in patients who had previously failed Rituximab. In addition, the drug appeared to be tolerated by patients who had previously undergone bone marrow transplant.