What this phase means
Phase 3: this treatment already looked useful in smaller studies. Now it is tested in a large group, often against standard care or a dummy treatment, to see if it should be approved.
Phase labels are FDA/ICH categories applied to the registry Phase field. They are not a finding that this study succeeded.
What the registry says happens
If you join, the listed intervention(s) are BGB-43395, Letrozole, or Abemaciclib. The registry lists allocation as randomized. This study wants to investigate the how well it works and safety of BGB-43395 in combination with letrozole compared with investigator's choice of cyclin-dependent kinase 4/6 inhibitor (CDK4/6i) in combination with letrozole in patients with advanced or metastatic hormone receptor positive (HR+)/human epidermal growth factor receptor 2 negative (HER2-) breast cancer (BC) who have not received prior systemic treatment for advanced or metastatic disease.
They plan to enroll about 1,056 people at 241 sites. Taking part typically means taking a study drug (or dummy pill) plus check-ins.
Official title (unrewritten)
An Open-Label, Randomized, Multicenter Phase 3 Study Investigating the Efficacy and Safety of BGB-43395 Plus Letrozole Versus CDK4/6 Inhibitors (Abemaciclib, Palbociclib, Ribociclib) Plus Letrozole in Patients With Advanced or Metastatic HR+/HER2- Breast Cancer Who Have Not Received Prior Systemic Anticancer Treatment for Advanced or Metastatic Disease
Interventions: BGB-43395, Letrozole, Abemaciclib, Palbociclib, Ribociclib
Primary outcome (registry wording): Progression-Free Survival (PFS) Determined by Blinded Independent Central Review (BICR)