Summary: This phase I trial tests the safety, side effects, and best dose of tazemetostat in combination with topotecan and pembrolizumab in treating patients with small cell lung cancer that has come back after a period of improvement (recurrent). Tazemetostat may stop the growth of tumor cells by blocking some of the enzymes needed for cell growth. Chemotherapy drugs, such as topotecan, work in different...

Summary: The participants of this study would have relapsed/refractory follicular lymphoma. Follicular lymphoma is a type of blood cancer. It is referred to as 'relapsed' when the disease has come back after a period of improvement after that follows a treatment regimen and 'refractory' when treatment no longer works. Stage 1 of this trial will study the safety and the level that adverse effects of each of...

Summary: This main aim of this trial will be to study the blood levels (known as pharmacokinetics) of the study drug tazemetostat. The pharmacokinetics of the study drug in participants with advanced solid tumors and moderate or severe hepatic (liver) impairment will be compared with participants with advanced malignancies and normal hepatic function. An advanced malignancy is a cancer that has recurred (c...