Results of a randomized, double-blind placebo-controlled phase 3 study evaluating idelalisib in combination with bendamustine and rituximab in patients with relapsed/refractory CLL and adverse prognostic features.

7514Background: Patients (pts) with relapsed CLL and adverse prognostic features respond poorly to standard treatment. Here we present a subgroup analysis from a phase 3 randomized double-blind placebo-controlled study. We evaluated progression-free survival (PFS) in this pt population enrolled between June 2012 and August 2014. Methods: All 416 pts (207/209 on the idelalisib (IDELA)/placebo [plb] arms, respectively) had BR for 6 cycles Q 28 days (B = 70 mg/m2 D1, D2 of each cycle; R = 375 mg/m2 C1 and 500 mg/m2 C2-6) and IDELA 150 mg BID or plb. IDELA/plb continued until independent review committee confirmation of disease progression, death, intolerable toxicity, or withdrawal of consent. Mutational analysis was centrally performed. Median time on study was 12 months. Results: Improvement in PFS was observed on the IDELA vs plb arm in all adverse-risk categories evaluated (Table). Conclusions: IDELA with BR consistently increased PFS in all risk categories evaluated. The safety profile was consistent wi...