Rituximab maintenance after first-line therapy with rituximab, fludarabine, cyclophosphamide, and mitoxantrone (R-FCM) for chronic lymphocytic leukemia
Mené sur 67 patients atteints d'une leucémie lymphocytaire chronique, cet essai évalue, du point de vue de la survie sans progression et de la survie globale à 4 ans, le rituximab en traitement d'entretien après un traitement de première ligne combinant rituximab, fludarabine, cyclophosphamide et mitoxantrone
The effectiveness of rituximab maintenance therapy in the treatment of CLL has been investigated in a phase II clinical trial that included an initial treatment with rituximab 500mg/m2 on day 1 (375 mg/m2 the first cycle), fludarabine 25 mg/m2 on days 1 to 3, cyclophosphamide 200mg/m2 on days 1 to 3, and mitoxantrone 6 mg/m2 on day 1, for six cycles, followed by a maintenance phase with rituximab 375 mg/m2 every three months for two years. Sixty-seven patients having achieved CR or PR with R-FCM were given maintenance therapy. At the end of the maintenance therapy 40.6% of patients were in CR with negative minimal residual disease (MRD), 40.6% in CR MRD-positive, 4.8% remained in PR, and 14% were considered failures. Six out of 29 patients (21%) in CR MRD-positive/PR after R-FCM improved their response upon rituximab maintenance. The 4-year PFS and OS were 74.8% and 93.7%, respectively. MRD status after R-FCM induction was the strongest predictor of PFS. Grade 3-4 neutropenia was observed in 8.5% of the cycles and 16 patients presented grade 3-4 infections. Maintenance with rituximab after R-FCM improved the quality of the response, particularly in patients MRD-positive after initial treatment, and obtained a prolonged PFS. This study is registered at www.clinicaltrialsregister.eu, identifier: 2005-001569-33.