Rituximab, Bendamustine and Cytarabine Followed by Venetoclax in High Risk Elderly Patients With MCL

Prospective, multicenter, phase II trial designed to evaluate whether the addition of Venetoclax after rituximab, bendamustine and cytarabine (R-BAC) to high risk patients with mantle cell lymphoma improves the results of the standard R-BAC, in terms of Progression Free Survival.

The aim of the study is to improve long term results of R-BAC, consolidating patients with high-risk (HR) features (defined as: elevated Ki67 and/or blastoid cytology and/or TP53 mutation after central pathology review) with Venetoclax (ABT-199), which has demonstrated relevant single agent activity in relapsed/refractory MCL in a Phase 1-2 trial. The updated Progression Free Survival curves of the R-BAC500 trial has shown that the expected 2-years PFS for patients with HR disease is 40% (H0), as compared to low-risk patients (LR) that have a 2-years PFS of 100%. The addition of Venetoclax to HR patients after R-BAC is expected to improve results and efficacy of this regimen in this "difficult -to- treat" population, that represents approximately 40-45 % of newly diagnosed elderly patients with MCL. It appears reasonable to treat with the experimental drug also LR patients that do not respond appropriately (less than CR) at the end of R-BAC. Since the number of such LR patients is hardly predictable based on the present experience with R-BAC500 trial, the analysis of this sub-cohort will be of exploratory nature, and thus assessed separately. The study objective is to evaluate whether the addition of venetoclax after R-BAC to HR patients improves the results of the standard R-BAC, in terms of Progression Free Survival .