# Phase III Study to Assess AZD9833+ CDK4/6 Inhibitor in HR+/HER2-MBC With Detectable ESR1m Before Progression (SERENA-6)

> **NCT04964934** · PHASE3 · ACTIVE_NOT_RECRUITING · sponsor: **AstraZeneca** · enrollment: 315 (actual)

## Conditions studied

- ER-Positive HER2-Negative Breast Cancer

## Interventions

- **DRUG:** AZD9833
- **DRUG:** AZD9833 Placebo
- **DRUG:** Anastrozole
- **DRUG:** Anastrozole placebo
- **DRUG:** Letrozole
- **DRUG:** Letrozole placebo
- **DRUG:** Palbociclib
- **DRUG:** Abemaciclib
- **DRUG:** Luteinizing hormone-releasing hormone (LHRH) agonist
- **DRUG:** Ribociclib

## Key facts

- **NCT ID:** NCT04964934
- **Lead sponsor:** AstraZeneca
- **Sponsor class:** INDUSTRY
- **Phase:** PHASE3
- **Study type:** INTERVENTIONAL
- **Status:** ACTIVE_NOT_RECRUITING
- **Start date:** 2021-06-30
- **Primary completion:** 2025-06-30
- **Final completion:** 2028-09-01
- **Target enrollment:** 315 (ACTUAL)
- **Last updated:** 2026-04-21


## Primary source

ClinicalTrials.gov registry: https://clinicaltrials.gov/study/NCT04964934

## Citation

> US National Library of Medicine, ClinicalTrials.gov registration NCT04964934, "Phase III Study to Assess AZD9833+ CDK4/6 Inhibitor in HR+/HER2-MBC With Detectable ESR1m Before Progression (SERENA-6)". Retrieved via AI Analytics 2026-06-24 from https://api.ai-analytics.org/clinical/NCT04964934. Licensed CC0.

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