A Study Evaluating the Efficacy and Safety of GDC-9545 Combined With Palbociclib Compared With Letrozole Combined With Palbociclib in Participants With Estrogen Receptor-Positive, HER2-Negative Locally Advanced or Metastatic Breast Cancer

Status:

Recruiting

III

Phase

1st

Line of Therapy

Advanced / Metastatic

Disease Stage

Biomarker(s)

ER+, HER2-

Investigational

Product

GDC-9545

Selective estrogen receptor degrader (SERD) (p.o.)

Treatment Arms

o Experimental: GDC-9545 + Letrozole-matched Placebo + Palbociclib

o Active Comparator: Letrozole + GDC-9545-matched Placebo + Palbociclib