CDK4/6is, Palbociclib, Ribociclib and Abemaciclib, have been effectively used in combination therapy [34,35], and have shown to be synergistic with drugs targeting other oncogenic pathways, including MEK, KRAS, BRAF, and ALK, in various cancers [4,13,14,36–39]. The gene discussed is KRAS; the disease is cancer.