23-BRE-56-AZ (D8531C00002): A Phase III, Open-Label, Randomised Study to Assess the Efficacy and Safety of Extended Therapy With Camizestrant Versus Standard Endocrine Therapy (Aromatase Inhibitor or Tamoxifen) in Patients With ER+/HER2- Early Breast Can

23-BRE-56-AZ (D8531C00002): A Phase III, Open-Label, Randomised Study to Assess the Efficacy and Safety of Extended Therapy With Camizestrant Versus Standard Endocrine Therapy (Aromatase Inhibitor or Tamoxifen) in Patients With ER+/HER2- Early Breast Cancer (CAMBRIA-1) Primary: To demonstrate superiority of extended therapy with camizestrant as compared to standard ET by assessment of overall survival (OS). Secondary: 1.To identify predictive biomarkers of camizestrant activity based on genetic, epigenetic, gene expression, and/or protein expression analysis of archival diagnostic/surgical tumour material. 2.To determine whether the presence of detectable ctDNA at baseline is a prognostic biomarker. 3.To identify mechanisms of acquired resistance to camizestrant and/or AI in the adjuvant setting. 4.To determine whether changes in ctDNA level are predictive of study treatment outcome and/or an early predictor of recurrence. 5.To collect and store germline DNA to assess CHIP to aid interpretation of ctDNA mutation monitoring. 6.To investigate the effect of germline genetic variations on drug exposure, response, and tolerability of camizestrant and/or AI in the adjuvant setting. Tertiary: 1.To assess patient-reported symptoms and treatment tolerability in patients treated with extended therapy with camizestrant relative to standard ET. 2.To assess TTD and change from baseline of functioning in patients treated with extended therapy with camizestrant relative to standard ET. 3.To assess patient-reported global impression of the severity of overall cancer symptoms in patients treated with extended therapy with camizestrant relative to standard ET. 4.To assess patient-reported global impression of change in health status in patients treated with extended therapy with camizestrant relative to standard ET.