Long‐term results of the treatment of patients with mantle cell lymphoma with cladribine (2‐CDA) alone (95‐80‐53) or 2‐CDA and rituximab (N0189) in the North Central Cancer Treatment Group

BACKGROUND. The objective of this study was to test cladribine (2‐CDA) alone and in combination with rituximab in patients with mantle cell lymphoma (MCL). METHODS. Patients with MCL were treated on 2 sequential trials. In Trial 95‐80‐53, patients received 2‐CDA as initial therapy or at relapse. In Trial N0189, patients received combination 2‐CDA and rituximab as initial therapy. In both trials, 2‐CDA was administered at a dose of 5 mg/m2 intravenously on Days 1 through 5 every 4 weeks for 2 to 6 cycles, depending on response. In Trial N0189, rituximab 375 mg/m2 was administered on Day 1 of each cycle. RESULTS. Results were reported for 80 patients. Twenty‐six previously untreated patients and 25 patients who had recurrent disease with a median age of 68 years received single‐agent 2‐CDA. The overall response rate (ORR) was 81% with 42% complete responses (CRs) in the previously untreated group. The median progression‐free survival (PFS) was 13.6 months (95% confidence interval [95% CI], 7.2‐22.1 months), and 81% of patients remained alive at 2 years. The ORR was 46% with a 21% CR rate in the recurrent disease group. The median PFS was 5.4 months (95% CI, 4.6‐13.1 months), and 36% of patients remained alive at 2 years. Twenty‐nine eligible patients with a median age of 70 years received 2‐CDA plus rituximab. The ORR was 66% (19 of 29 patient), and the CR rate was 52% (15 of 29 patients). The median duration of response for patients who achieved a CR had not been reached at the time of the current report, and only 3 of the patients who achieved a CR developed recurrent disease at a median follow‐up of 21.5 months. CONCLUSIONS. 2‐CDA had substantial single‐agent activity in both recurrent and untreated MCL, and the results indicated that it may be administered safely to elderly patients. The addition of rituximab to 2‐CDA may increase the duration of response. Cancer 2008. © 2008 American Cancer Society. In this study, the authors established that cladribine has substantial single‐agent activity in both recurrent and untreated mantle cell lymphoma and may be administered safely to elderly patients. The results also indicated that the addition of rituximab to cladribine may increase the duration of response.