Purpose

The primary objectives of this study is to evaluate the safety and efficacy of idelalisib (GS-1101, CAL-101) in participants with previously treated indolent non-Hodgkin lymphoma (iNHL). Eligible patients will initiate oral therapy with idelalisib at a starting dose of 150 mg twice per day. Treatment with idelalisib can continue in compliant participants for up to twelve 28-day cycles of idelalisib. Participants who appear to be benefiting from treatment at the completion of 12 cycles of treatment with idelalisib may be eligible for participation in a long-term safety extension study of idelalisib.