SERENA-6: A Phase III, Double-blind, Randomised Study to Assess Switching to AZD9833 (a Next Generation, Oral SERD) + CDK4/6 Inhibitor vs Continuing Aromatase Inhibitor (Letrozole or Anastrozole) + CDK4/6 Inhibitor in HR+/HER2- MBC Patients with Detectable ESR1 Mutation Without Disease Progression During 1L Treatment with Aromatase Inhibitor + CDK4/6 Inhibitor A ctDNA Guided Early Switch Study

Status

Active, not recruiting

Phases

Phase 3

Study type

Interventional

Source

EU CTIS

Registry ID

CTIS2023-503990-39-00

Acronym

D8534C00001

Enrollment

128

Registered

2024-09-10

Start date

2021-09-30

Completion date

Unknown

Last updated

2025-09-24

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Estrogen Receptor-Positive, HER-2 negative Advanced Breast Cancer

Brief summary

Progression-free survival (PFS) is defined as the time from randomisation until progression per RECIST 1.1 as assessed by the investigator at the local site, or death due to any cause.

Detailed description

Overall survival (OS), Progression-free survival 2 (PFS2), Objective response rate (ORR) assessed by the Investigator as defined by RECIST version 1.1, Chemotherapy-free survival, Clinical benefit rate at 24 weeks (CBR24), Time to first subsequent anti-cancer therapy (TFST), Time to second subsequent therapy (TSST), Time to deterioration (TTD), Plasma concentration of AZD9833 at specified timepoints, Change from baseline in EORTC QLQ-C30 and EORTC QLQ-BR23 scale

Interventions

DRUGcamizestrant

DRUGPlacebo to match camizestrant

DRUGABEMACICLIB

DRUGLETROZOLE

DRUGArimidex® 1 mg Filmtabletten

DRUGGOSERELIN ACETATE

DRUGLEUPRORELIN ACETATE

DRUGIBRANCE 100 mg film-coated tablets

DRUGIBRANCE 125 mg film-coated tablets

DRUGCamizestrant

DRUGRIBOCICLIB

DRUGPlacebo to match anastrozole

DRUGIBRANCE 75 mg film-coated tablets

DRUGPlacebo to match letrozole

Eligibility

Sex/Gender

All

Age

18 Years to No maximum

Design outcomes

Primary

Measure	Time frame
Progression-free survival (PFS) is defined as the time from randomisation until progression per RECIST 1.1 as assessed by the investigator at the local site, or death due to any cause.	—

Secondary

Measure	Time frame
Overall survival (OS), Progression-free survival 2 (PFS2), Objective response rate (ORR) assessed by the Investigator as defined by RECIST version 1.1, Chemotherapy-free survival, Clinical benefit rate at 24 weeks (CBR24), Time to first subsequent anti-cancer therapy (TFST), Time to second subsequent therapy (TSST), Time to deterioration (TTD), Plasma concentration of AZD9833 at specified timepoints, Change from baseline in EORTC QLQ-C30 and EORTC QLQ-BR23 scale	—

Measure

Time frame

—

Countries

Austria, Belgium, Bulgaria, France, Germany, Hungary, Italy, Norway, Poland, Portugal, Slovakia, Spain

Outcome results

None listed

Source: EU CTIS · Data processed: Feb 4, 2026