A phase 0/2 clinical trial was initiated at the Ivy Brain Tumor Center (Phoenix, AZ, USA) to investigate the potential synergism of LY3214996, an extracellular signal-regulated kinase (ERK) 1/2 inhibitor, and abemaciclib, a CDK4/6 inhibitor, in a recurrent GBM patient population (NCT04391595). The gene discussed is CDK4; the disease is brain neoplasm.