Medline ® Abstract for Reference 61
of 'Treatment of relapsed or refractory mantle cell lymphoma'
A phase 1 study of the PI3Kδinhibitor idelalisib in patients with relapsed/refractory mantle cell lymphoma (MCL).
Kahl BS, Spurgeon SE, Furman RR, Flinn IW, Coutre SE, Brown JR, Benson DM, Byrd JC, Peterman S, Cho Y, Yu A, Godfrey WR, Wagner-Johnston ND
Blood. 2014 May;123(22):3398-405. Epub 2014 Mar 10.
Idelalisib, an oral inhibitor of phosphatidylinositol-3-kinaseδ(PI3Kδ), was evaluated in a 48-week phase 1 study (50-350 mg daily or twice daily) enrolling 40 patients with relapsed or refractory mantle cell lymphoma (MCL). Primary outcome was safety and dose-limiting toxicity (DLT). Secondary outcomes were pharmacokinetic parameters, pharmacodynamic effects, overall response rate (ORR), progression-free survival (PFS), and duration of response (DOR). Patients without DLT and no evidence of disease progression after 48 weeks enrolled in the extension study. Patients had median age of 69 years (range, 52-83) and received median of 4 prior therapies (1-14); 17 of 40 patients (43%) were refractory to their most recent treatment. Median duration of idelalisib treatment was 3.5 months (range, 0.7-30.7), with 6 (15%) continuing extension treatment. Common grade≥3 adverse events (AEs) included (total%/grade≥3%) diarrhea (40/18), nausea (33/5), pyrexia (28/0), fatigue (25/3), rash (23/3), decreased appetite (20/15), upper respiratory infection (20/0), pneumonia (13/10), and alanine transaminase or aspartate transaminase elevations (60/20). ORR was 16 of 40 patients (40%), with CR in 2 of 40 patients (5%). Median DOR was 2.7 months, median PFS was 3.7 months,and 1-year PFS was 22%. These data provide proof of concept that targeting PI3Kδis a viable strategy and worthy of additional study in MCL. This trial was registered at www.clinicaltrials.gov as #NCT00710528.
Department of Medicine, University of Wisconsin Carbone Cancer Center, Madison, WI;