A phase I study of bendamustine, lenalidomide and rituximab in relapsed and refractory lymphomas.

Summary Many patients with non-Hodgkin (NHL) or Hodgkin lymphoma (HL) relapse or are refractory to initial therapy and require additional options. Bendamustine (B), lenalidomide (L) and rituximab (R) each have activity in this setting. This study was performed to determine the safety of BLR and its optimal phase II dose. Patients with NHL or HL failing standard therapies received B (90 mg/m2 days 1, 2 every 28 days), and L (escalating from 5 mg 21/28 days) for six cycles, followed by 6 months of L. At the highest dose R 375 mg/m2 on day one of each cycle was added for patients with B-NHL. Histologies included diffuse large B-cell lymphoma (DLBCL, 11), marginal zone lymphoma (3), HL (2), and one each of transformed follicular lymphoma, Sezary syndrome, Waldenstrom macroglobulinaemia and mantle cell lymphoma. Neutropenia was the most common grade 3 and 4 toxicity, but no maximum tolerated dose was identified. Of 20 patients, seven responded (35%), including four complete remissions, with five unmaintained responses from 28+ to 37+ months, including 2 DLBCL. BR with 20 mg l at, 21/28 days achieved durable responses; however, in light of its modest activity, and the availability of newer targeted therapies, the future of BLR is uncertain.