Obinutuzumab in Marginal Zone Lymphoma

For marginal zone lymphoma (MZL) Rituximab in combination with conventional chemotherapy are widely used for those patients who fail local therapy or do not qualify for such. Depending on the MZL subtype Rituximab/chemotherapy is able to induce in part long remissions, but do not prevent relapse later on. In addition, chemotherapy associated toxicity is often problematic in MZL patients, who are mostly of advanced age. Thus, chemotherapy - free approaches are highly attractive for this patient group. Rituximab single agent is a widely used chemotherapy - free approach in MZL, but was significantly inferior compared to Rituximab/chlorambucil in a large randomized prospective clinical trial in treatment naïve MZL with a CR rate of 56 % vs. 80%, respectively (P\<0.001).Thus, it is the major aim to develop chemotherapy - free approaches for MZL, which approach efficacy of rituximab/chemotherapy combinations, but avoid chemotherapy associated toxicities. This in particular important in MZL as many physicians are reluctant to treat these often elderly patients with more intense treatments and prefer single agent therapies in these very often well and long responding lymphoma subtype. The type II anti-CD20 antibody Obinutuzumab (OBINUTUZUMAB) has demonstrated remarkable activity in follicular lymphoma and superiority to Rituximab in combination with chemotherapy in treatment naïve (Gallium trial) and rituximab refractory follicular lymphoma (Gadolin trial) as well as in CLL in combination with chlorambucil. Based on these observations it is the aim of this study to test the toxicity and efficacy of the anti-CD20 antibody Obinutuzumab (OBINUTUZUMAB) in patients with newly diagnosed MZL in need of treatment, who are not eligible or failed local therapy, following the assumption that this novel anti-CD20 antibody is significantly more effective than Rituximab single agent therapy, and avoids chemotherapy - related toxicity. For efficacy the rate of complete remissions (according to the GELA criteria for gastric MALT or to the Cheson 2007 criteria for non-gastric extranodal, nodal and splenic MZL) after induction therapy will be primarily analysed. For toxicity treatment associated adverse events, quality of life and cumulative incidence of secondary malignancies will be documented. The study is a multicenter, single-arm, open-label, phase II trial of 6 cycles of Obinutuzumab in the induction phase followed by a maintenance phase for a maximum of 12 infusions of Obinutuzumab every 8 weeks in patients aged ≥ 18 years with previously untreated MZL in need of treatment. The study flow will be as follows: * Previously untreated patients will be screened for eligibility for the trial. If the patient is eligible for the study, the patient will be registered before the first cycle of induction treatment. * Patients who progress at any time point during induction are considered as treatment failure. They will be followed up for overall survival until death. * Patients, who achieve at least a SD after induction treatment will be eligible to receive maintenance therapy with Obinutuzumab. It is expected that a total of 56 patients at approximately 20 investigator sites will be registered. Every patient will receive treatment over a time period of 6 x 4 weeks, followed by a maintenance phase of every 8 weeks for a maximum of 12 infusions until progression or study drug - related intolerable toxicity. Patient will be monitored every 3 months for 2 additional years, subsequently every 6 months for three additional years.