A phase II study of abemaciclib, a cyclin-dependent kinase 4 and CDK 6 inhibitor, met its primary endpoint of reducing expression of Ki67, a biomarker of cell proliferation, after two weeks of treatment.
Further positive results from the phase III SERENA-6 trial showed camizestrant plus a cyclin-dependent kinase 4/6 inhibitor—palbociclib, ribociclib or abemaciclib—maintained its progression-free survival benefit with longer follow-up and delivered a statistically significant and clinically meaningful improvement in second progression-free survival, demonstrating sustained benefit beyond initial treatment.
