Phase II study of bortezomib in combination with rituximab, cyclophosphamide and prednisone with or without doxorubicin followed by rituximab maintenance in patients with relapsed or refractory follicular lymphoma.

This non-comparative phase II study (ClinicalTrials.gov: NCT00715208) evaluated bortezomib in place of vincristine in established rituximab-chemotherapy regimens in relapsed/refractory follicular (FL) or marginal zone lymphoma (MZL). Patients were allocated (physician/patient preference) to receive six 21-d cycles of: bortezomib 1·6 mg/m(2) (days 1, 8), rituximab 375 mg/m(2) (day 1), cyclophosphamide 1000 mg/m(2) (day 1) and prednisone 100 mg (days 1-5; VR-CP; 47 FL, 1 MZL patients); or bortezomib, rituximab, prednisone per VR-CP, cyclophosphamide 750 mg/m(2) and doxorubicin 50 mg/m(2) (day 1; VR-CAP; 4 FL, 2 MZL, 1 chronic lymphocytic leukaemia patients). With VR-CP, the response rate was 77%, with a 27% complete response rate. After a median follow-up of 10·9 months, 40% of patients had relapsed/progressed or died. Median duration of response and progression-free survival was 21·9 and 14·9 months, respectively. Common drug-related grade ≥3 adverse events were neutropenia (25%), thrombocytopenia (6%) and lymphopenia (6%). Thirteen (27%) patients reported peripheral neuropathy (one grade 3). With VR-CAP, one FL patient achieved complete response and three FL and two MZL patients achieved partial responses. Three patients reported drug-related grade 1/2 peripheral neuropathy. Weekly bortezomib and rituximab represents an active, feasible treatment platform in FL. VR-CP was active and well tolerated in patients with relapsed/refractory FL.