The maximum tolerated dose (MTD) of PQR309 in patients with advanced solid tumours was defined as 80 mg once daily given continuously (q.d. schedule) in a previous phase 1 study [8]. The safety run-in of this study will follow a modified 3 + 3 design to evaluate the safety of 60 and 80 mg PQR309 in patients with relapsed or refractory lymphoma administered p.o. once daily during a DLT (dose-limiting toxicity) period of 28 days.