Experimental Design:
BREAST CANCER
This phase Ia/Ib dose-escalation/-expansion study (NCT03332797) evaluated the safety, pharmacokinetics, pharmacodynamics, and preliminary antitumor activity of giredestrant in estrogen receptor–positive HER2-negative locally advanced/metastatic breast cancer. The single-agent dose-escalation stage evaluated giredestrant 10, 30, 90, or 250 mg once daily. The dose-expansion stage evaluated single-agent giredestrant at 30, 100, and 250 mg once daily. Dose-escalation and -expansion phases also evaluated giredestrant 100 mg combined with palbociclib 125 mg.