FDA Approval: Idelalisib Monotherapy for the Treatment of Patients with Follicular Lymphoma and Small Lymphocytic Lymphoma

On July 23, 2014, the FDA granted accelerated approval to idelalisib (Zydelig tablets; Gilead Sciences, Inc.) for the treatment of patients with relapsed follicular B-cell non–Hodgkin lymphoma or relapsed small lymphocytic lymphoma (SLL) who have received at least two prior systemic therapies. In a multicenter, single-arm trial, 123 patients with relapsed indolent non–Hodgkin lymphomas received idelalisib, 150 mg orally twice daily. In patients with follicular lymphoma, the overall response rate (ORR) was 54%, and the median duration of response (DOR) was not evaluable; median follow-up was 8.1 months. In patients with SLL, the ORR was 58% and the median DOR was 11.9 months. One-half of patients experienced a serious adverse reaction of pneumonia, pyrexia, sepsis, febrile neutropenia, diarrhea, or pneumonitis. Other common adverse reactions were abdominal pain, nausea, fatigue, cough, dyspnea, and rash. Common treatment-emergent laboratory abnormalities were elevations in alanine aminotransferase, aspartate aminotransferase, gamma-glutamyltransferase, absolute lymphocytes, and triglycerides. Continued approval may be contingent upon verification of clinical benefit in confirmatory trials. Clin Cancer Res; 21(7); 1525–9. ©2015 AACR . See related article by Gandhi et al., p. 1537