A Study of Taselisib + Fulvestrant Versus Placebo + Fulvestrant in Participants With Advanced or Metastatic Breast Cancer Who Have Disease Recurrence or Progression During or After Aromatase Inhibitor Therapy

Official Title

A Phase III, Double-Blind, Placebo-Controlled, Randomized Study of Taselisib Plus Fulvestrant Versus Placebo Plus Fulvestrant in Postmenopausal Women With Estrogen Receptor-Positive and HER2-Negative Locally Advanced or Metastatic Breast Cancer Who Have Disease Recurrence or Progression During or After Aromatase Inhibitor Therapy

Summary:

This international, multicentre, randomized, double-blinded, placebo-controlled study is designed to compare the efficacy and safety of taselisib + fulvestrant with that of placebo + fulvestrant in postmenopausal women with estrogen receptor (ER)-positive, human epidermal growth factor receptor-2 (HER2)-negative, oncogene that encodes for phosphatidylinositol-4,5-bisphosphate 3-kinase (PIK3CA)-mutant, unresectable, locally advanced or metastatic breast cancer after recurrence or progression during or after an aromatase inhibitor (AI) therapy. There will be a 2:1 randomization to the taselisib arm versus the placebo arm. Enrollment will be enriched for participants with PIK3CA mutant tumours via central testing. The anticipated duration of the study is approximately 3.5 years.

Trial Description

Primary Outcome:

• Progression-Free Survival (PFS) as Assessed by Investigator Using Response Evaluation Criteria in Solid Tumours (RECIST) Version 1.1 (v1.1)

• Percentage of Participants With Objective Response (Partial Response [PR] Plus Complete Response [CR]), as Assessed Using RECIST v.1.1
• Overall Survival (OS)
• Percentage of Participants With Clinical Benefit, as Assessed According to RECIST v1.1
• Duration of Objective Response, as Assessed by Investigator Using RECIST v1.1
• PFS as Assessed by Blinded Independent Central Review (BICR) Using RECIST v1.1
• Percentage of Participants With Adverse Events
• Maximum Observed Plasma Concentration (Cmax) of Taselisib
• Minimum Observed Plasma Concentration (Cmin) of Taselisib
• Change From Baseline in European Organization for Research and Treatment of Cancer (EORTC) Quality of Life Questionnaire Core 30 (QLQ-C30) Score
• Change From Baseline in Modified EORTC Quality of Life Questionnaire Breast Cancer Module 23 (QLQ-BR23) Score

View this trial on ClinicalTrials.gov