Low Toxicity Profile of the Combination of Bendamustine Plus Rituximab (BR) in Elderly FRAIL Patients with Newly Diagnosed DLBCL

Introduction: R-CHOP is the gold standard for the treatment of elderly patients with DLBCL. However, unfit and frail patients frequently do not qualify for CHOP-based chemotherapy. Alternatives are an urgent medical need. Bendamustine plus rituximab (BR) has been established as a standard treatment of indolent lymphomas and preliminary data have shown a promising activity in DLBCL, both in the relapsing and upfront setting.

Methods: Within the Fondazione Italiana Linfomi (FIL), we started a phase II study (R-BENDA frail study, EUDRACT2011-001421-24) in elderly patients (>70 years) with a newly diagnosed DLBCL not suitable for R-CHOP-based chemotherapy. All patients were evaluated according to ADL, IADL and CIRS-G and were considered FRAIL if the following criteria were meet: in patients aged 70-80 ADL<4 or IADL<5 or one grade 3 comorbidity or >8 grade 2 comorbidities; in patients older than 80 years ADL>5 or IADL>6 or 5-8 grade 2 comorbidities. Patients received bendamustine at a dose of 90 mg/m² daily on days 1 and 2 of each 28-day cycle along with rituximab on day 1 for up to 6 cycles.

Results: From February 2012 to February 2014, 49 patients were enrolled in 24 Italian centers. The majority (57%) were male and 57% had stage III-IV with 41% elevated LDH. The median age was 82. Overall, 83% of the planned cycles were delivered without dose reduction or delay; grade 3/4 neutropenia was reported in 25% of cycles followed by anemia 21%, and thrombocytopenia 20%. One case of febrile neutropenia was observed. Grade 3-4 non-hematological toxicity was mild and reported in 6% of cycles including 3 episodes of cardiovascular events and 7 other cases of different toxicities (one creatinine increase, one fatigue, one bleeding, one peripheral neurotoxicity, one hyponatriemia, one hyperglycemia and one liver toxicity). Two deaths during treatment have been observed (cardiac failure and sudden death). At the interim analysis (23 patients) the overall response rate was 56% with a complete response rate of 39%.

Conclusions: Combination therapy with BR demonstrates low toxicity profile in this high risk population. The promising results on activity can encourage clinicians to considered BR for the treatment of FRAIL elderly patients with DLBCL not eligible for R-CHOP.