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.
The phase III persevERA Breast Cancer study, evaluating investigational giredestrant in combination with palbociclib for people with oestrogen receptor (ER)-positive, human epidermal growth factor receptor 2 (HER2)-negative, locally advanced or metastatic breast cancer, did not meet its primary objective of a statistically significant improvement in progression-free survival in the intent-to-treat population versus letrozole plus palbociclib, but a numerical improvement was observed.
