Randomized Multicenter Trial of Cladribine Alone (C) or in Combination with Cyclophosphamide (CC), and COP in Previously Untreated Low Grade B-Cell Non-Hodgkin Lymphoma Patients: The First Interim Analysis.

To comparatively assess first-line treatment with cladribine alone (C) or in combination with cyclophosphamide (CC), and COP (cyclophosphamide, vincristine, prednisone) in low grade B-cell non-Hodgkin lymphoma (NHL), previously untreated patients (pts) with Ann Arbor stage II–IV were randomly allocated to receive 6 monthly courses of either C, CC, or COP. End points were treatment response, freedom from progression (FFP) and overall survival (OS), and tolerance. From June 1, 2000, 165 pts were randomized in 17 centers. The first interim analysis performed at July 1, 2004 included 105 out of 165 randomized pts (63.6%) who have completed at least six cycles of the scheduled chemotherapy. Of 105 analyzed pts, 38 (36.2%) were diagnosed as small lymphocytic, lymphoplasmocytoid 8 (7.6%), marginal-zone 22 (21%), follicular 33 (31.4%), and not otherwise specified low grade B-cell NHL 4 (3.8%). Randomization constituted comparable groups, including international Prognostic Index variables. Compared to C and CC, COP induced lower overall response rates (75%, 85%, 51%, χ 2 test p 2 test p 2 = 15.1, log-rank test p 2 = 1.15, log-rank test p=.56). Incidences of infections (7% versus 15% versus 11%) and non-hematological side effects (7% versus 7.5% versus 16%) were similar in the randomize groups, whereas CC but not C induced more frequent cytopenias compared to COP (30% versus 11%, χ 2 test p 2 test p