The Ribvd Regimen (Rituximab IV, Bendamustine IV, Velcade SC, Dexamethasone IV) Offers a High Complete Response Rate In Elderly Patients With Untreated Mantle Cell Lymphoma. Preliminary Results Of The Lysa Trial “Lymphome Du Manteau 2010 SA”

This prospective phase II trial (Nov 2011- Dec 2012), supported by the LYSA group, aimed to evaluate the impact on PFS of the RiBVD regimen in newly diagnosed, previously untreated, elderly MCL patients (>65 years or not eligible for ASCT) (NCT01457144). Inclusion criteria were: WHO 2008 MCL not previously treated, CD20 positive, ECOG 0-2, AA stage II-IV, no CNS involvement or active HBV/HCV/HIV infection. Patients were scheduled to receive a total of 6 cycles of the RiBVD regimen, if they responded (IWG criteria) after 4 cycles. The regimen was administered every 4 weeks with Rituximab 375 mg/m² IV on day(D)1, Bendamustine 90 mg/m² IV on D1 and 2, Dexamethasone 40 mg/m² IV on D2 and bortezomib (Velcade®) 1.3 mg/m² subcutaneously on D1, 4, 8 and 11. Primary prophylaxis with acyclovir was mandatory for Herpes virus reactivation, but there was no recommendation for bacterial prevention. Herein we present preliminary analysis of the trial after 4 RiBVD cycles. Results: A total of 76 patients were included, one was excluded because of HBV active disease and 5 had insufficient data reported in the database. To date we analyzed 70 patients. Patients characteristics: sex ratio M/F 49/21, median age 72 years (y) [64-83] (2 patients were 64 y old), AAstage II/III-IV 5/65, ECOG 0-1/2 59/11, MIPI score low/intermediate/high 3/19/48. Response: 61 responded (ORR=87%), with 19 in PR (26%) and 42 in CR/CRu (60%). Four patients died from pneumonia (n=1), cardiac arrest (n=2) and one following Progressive Multifocal Leukoencephalopathy. Three patients have progressed after 3 cycles. Sixty one patients were analysed by PETscan after 4 cycles, 39 (64%) reached a CR (30 were in CR/CRu and 9 in PR) and 22 remained PET positive (11 patients were in CR/CRu, 10 in PR and 1 stable). RiBVD cycles: 271 cycles were administered out of 280 planned (97%). Twenty four (9%) were delayed, 10 for toxicity. All but one planned Bendamustine doses (n=542) were administered with dosing modified 17 times (3%), mostly for hematological toxicity (n=14). Regarding Bortezomib, 79% (1028/1084) of planned doses were administered, it was prematurely stopped (56, 4%) for neurotoxicity (10 instances) or hematological side effects (46). Rituximab was not administered in 4 instances. Hematologic toxicities: Over the 271 cycles administered, neutropenia was reported in 104 cycles [56 grade 3/4 (g3/4) (21%)], 2.5% with fever; thrombopenia in 181 cycles [41 g3/4 (15%)]; anemia in 210 cycles, [6 g3/4 (2%)]. Non-hematologic toxicities:Reported in >10% of the cycles were : allergic reactions (10.3%, g3/4 <1%), fatigue (40%, g3/4 5%), fever without neutropenia (12%, g3/4 none), weight loss (12%, g3/4 0%), cutaneous rash (12%, g3/4 1.5%), gastrointestinal (40%, g3/4 1.5% ; diarrhea 8%, constipation 17% or emesis 15%), elevated transaminases (14%, g3/4 1%), creatinin (13%, g3/4 none), or glucose (18%, g3/4 1%) ; neuropathy (sensitive or pain) (25%, g3/4 4%). Serious adverse events (SAE) additional to the 4 deaths, were 12 infections including 3 pneumonias (no pneumocystosis), one listeriosis and 2 herpes zoster. Four febrile neutropenia and 3 cutaneous hypersensitivity episodes were also reported.