Title
A Phase 3 Open-label Randomized Study Assessing the Efficacy and Safety of RLY-2608 + Fulvestrant Versus Capivasertib + Fulvestrant as Treatment for PIK3CA-mutant Hormone Receptor Positive, Human Epidermal Growth Factor Receptor 2 Negative (HR+/HER2-) Locally Advanced or Metastatic Breast Cancer Following Recurrence or Progression On or After Treatment with a CDK4/6 Inhibitor

Description
A Phase 3 Open-Label Randomized Study Assessing the Efficacy and Safety of RLY-2608 + Fulvestrant Versus Capivasertib + Fulvestrant as Treatment for PIK3CA-mutant Hormone Receptor Positive, Human Epidermal Growth Factor Receptor 2 Negative (HR+/HER2-) Locally Advanced or Metastatic Breast Cancer Following Recurrence or Progression On or After Treatment With a CDK4/6 Inhibitor

Objective
Primary Objective:
1. To compare the efficacy of RLY-2608 + fulvestrant relative to capivasertib + fulvestrant by assessment of PFS within the overall and kinase populations by BICR.

Secondary Objective:
1. To compare the efficacy of RLY-2608 + fulvestrant relative to capivasertib + fulvestrant by assessment of overall survival (OS) within the overall and kinase populations.

Treatment This is a global, multicenter, open-label, randomized Phase 3 study comparing the efficacy and safety of RLY-2608 + fulvestrant to capivasertib + fulvestrant for the treatment of patients with HR+/HER2- ABC with PIK3CA mutation following recurrence or progression on or after treatment with a CDK4/6 inhibitor.

Key Eligibility For full study eligibility see this study's ClinicalTrials.gov record.

Applicable Disease Sites
Breast

Participating Institutions
UW Health Eastpark Medical Center; UW Health University Hospital