GSK126 is a potent and highly selective EZH2 inhibitor that targets both wild-type EZH2 and Y641 mutant EZH2.1346 However, a phase I clinical trial assessing its safety, pharmacokinetics, pharmacodynamics, and clinical activity in patients with relapsed or refractory DLBCL, other NHLs, multiple myeloma, and solid tumors was terminated. The gene discussed is EZH2; the disease is plasma cell myeloma.