Pan-phosphatidylinositol 3-kinase inhibition with buparlisib in patients with relapsed or refractory non-Hodgkin lymphoma

Phosphatidylinositol 3-kinase mechanistic target of rapamycin pathway activation plays a role in the pathogenesis of non-Hodgkin lymphoma. This multicenter, open-label Phase II study evaluated buparlisib (BKM120), a pan-class I Phosphatidylinositol 3-kinase inhibitor, in patients with relapsed or refractory non-Hodgkin lymphoma. Patients received buparlisib 100 mg once daily in three separate cohorts (diffuse large B-cell lymphoma, mantle cell lymphoma, or follicular lymphoma) until progression, intolerance, or withdrawal of consent. The primary endpoint was overall response rate based on a 6-month best overall response by cohort; secondary endpoints included progression-free survival, duration of response, overall survival, safety, and tolerability. Overall, 72 patients (diffuse large B-cell lymphoma [n=26], mantle cell lymphoma [n=22], and follicular lymphoma [n=24]) were treated. The overall response rate was 11.5%, 22.7%, and 25.0% in patients with diffuse large B-cell lymphoma, mantle cell lymphoma, and follicular lymphoma, respectively; two patients (one each in diffuse large B-cell lymphoma and mantle cell lymphoma cohorts) achieved a complete response. The most frequently reported (>20%) any-grade adverse events in the safety population were hyperglycemia, fatigue, and nausea (36.1% each), depression (29.2%), diarrhea (27.8%), and anxiety (25.0%). The most common grade 3/4 AEs included hyperglycemia (11.1%) and neutropenia (5.6%). Buparlisib showed activity in non-Hodgkin lymphoma, with disease stabilization and sustained tumor burden reduction in some patients with relapsed or refractory non-Hodgkin lymphoma, and acceptable toxicity. Development of mechanism-based combination regimens with buparlisib is warranted. (Funded by Novartis Pharmaceuticals; ClinicalTrials.gov number, NCT01693614)