Study Comparing the Zevalin Regimen With no Further Treatment in DLBCL Patients Who Are in Complete Remission After CHOP-R

Inclusion Criteria:

• Histologically confirmed, Ann Arbor stage II, III, or IV DLBCL according to the REAL/WHO classification (from initial diagnosis made prior to starting CHOP-R therapy)
• Central pathology review confirming the DLBCL diagnosis and CD20 positivity, and no evidence of DLBCL in bone marrow
• First-line treatment of DLBCL must have been 6 or 8 cycles of standard CHOP chemotherapy (cyclophosphamide 750 mg/m2, doxorubicin 50 mg/m2, vincristine 1.4 mg/m2 up to a maximum of 2 mg on day 1, and at least 40 mg/m2/day prednisone on Days 1 to 5 every three weeks, with generally accepted adjustments in dose or frequency due to toxicity, patient scheduling, etc.) in combination with rituximab (375 mg/m2)
• Complete remission (CR) or unconfirmed complete remission (CRu) according to the International Workshop Response Criteria for NHL described by Cheson et al and modified for this study after first-line treatment with CHOP-R. CT scans of chest, abdomen, pelvis, and neck (if applicable) must have been performed within 6 weeks after the last dose of the last course of CHOP-R. Applicability of the neck CT means that the patient had involvement of the neck region by palpation / physical examination at first diagnosis (pre-CHOP-R).
• Central radiographic review of the CT scans (chest, abdomen, pelvis and if applicable, neck) from before and after first-line treatment with CHOP-R fulfilling the radiological requirements for CR/CRu
• Patients 60 years of age or older at time of randomization
• WHO performance status (PS) of 0 to 2 within 1 week of randomization
• Absolute neutrophil count (ANC)greater than or equal to 1.5 x 10^9/L within 1 week of randomization
• Hemoglobin (Hgb) greater than or equal to 10 g/dL within 1 week of randomization
• Platelets greater than or equal to 150 x 10^9/L within 1 week of randomization
• Life expectancy of 3 months or longer
• Written informed consent obtained according to local guidelines

Exclusion Criteria:

• Presence of any other malignancy or history of prior malignancy except non-melanoma skin tumors or stage 0 (in situ) cervical carcinoma
• Prior radioimmunotherapy, radiation therapy, or any other NHL therapy except first-line CHOP-R
• Presence of gastric, central nervous system (CNS), or testicular lymphoma at first diagnosis
• Histological transformation of low-grade NHL
• Known seropositivity for hepatitis C virus (HCV) or hepatitis B surface antigen (HbsAg)
• Known history of HIV infection
• Abnormal liver function: total bilirubin > 1.5 x ULN or ALT > 2.5 x ULN within 1 week of randomization
• Abnormal renal function: serum creatinine > 2.0 x ULN within 1 week of randomization
• Nonrecovery from the toxic effects of CHOP-R therapy
• Known hypersensitivity to murine or chimeric antibodies or proteins
• G-CSF or GM-CSF therapy within two weeks (or four weeks if pegylated) prior to screening laboratory sampling
• Concurrent severe and/or uncontrolled medical disease (e.g., uncontrolled diabetes,congestive heart failure, myocardial infarction within 6 months of study, unstable and uncontrolled hypertension, chronic renal disease, or active uncontrolled infection) which could compromise participation in the study
• Male and female patients of child-bearing potential unwilling to practice effective contraception during the study and unwilling or unable to continue contraception for 12 months after their last dose of study treatment
• Female patients who are pregnant or are currently breastfeeding
• Treatment with investigational drugs less than 4 weeks before the planned Day 1 or nonrecovery from the toxic effects of such therapy
• Surgery less than 4 weeks before the planned Day 1 or nonrecovery from the side effects of such surgery
• Concurrent systemic corticosteroid use for any reason except as premedication in case of known or suspected allergies to contrast media or as premedication for potential side effects of rituximab treatment
• Unwillingness or inability to comply with the protocol