A PHASE III RANDOMIZED, DOUBLE-BLIND, PLACEBO-CONTROLLED, MULTICENTER STUDY EVALUATING THE EFFICACY AND SAFETY OF GDC-9545 COMBINED WITH PALBOCICLIB COMPARED WITH LETROZOLE COMBINED WITH PALBOCICLIB IN PATIENTS WITH ESTROGEN RECEPTOR-POSITIVE, HER2-NEGATIVE LOCALLY ADVANCED OR METASTATIC BREAST CANCER

Status

Active, not recruiting

Phases

Phase 3

Study type

Interventional

Source

EU CTIS

Registry ID

CTIS2023-506911-16-00

Acronym

BO41843

Enrollment

259

Registered

2024-03-27

Start date

2020-12-04

Completion date

Unknown

Last updated

2025-12-16

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

Conditions

ESTROGEN RECEPTOR-POSITIVE, HER2-NEGATIVE LOCALLY ADVANCED OR METASTATIC BREAST CANCER

Brief summary

1. Progression-free survival (PFS

Detailed description

1. Overall survival (OS), 2. Objective response rate (ORR), 3. Duration of response (DOR), 4. Clinical benefit rate (CBR), 5. Time to confirmed deterioration (TTCD) in pain level, 6. TTCD in pain presence and interference, 7. TTCD in physical functioning (PF), 8. TTCD in role functioning (RF), 9. TTCD in global health status (GHS) and quality-of-life (QoL), 10. Incidence and severity of adverse events, with severity determined according to National Cancer Institute (NCI) Common Terminology Criteria for Adverse Events, Version 5.0 (CTCAE v5.0), 11. Change from baseline in targeted vital signs, 12. Plasma concentration of GDC-9545 at specified timepoints, 13. Plasma concentration of palbociclib at specified timepoints

Interventions

DRUGIBRANCE 75 mg hard capsules

DRUGIBRANCE 100 mg hard capsules

DRUGIBRANCE 125 mg hard capsules

DRUGPlacebo Letrozole

DRUGFemara® 2

DRUG5 mg Filmtabletten

DRUGPlacebo Giredestrant

DRUGRO7197597

DRUGIBRANCE 75 mg film-coated tablets

DRUGIBRANCE 125 mg film-coated tablets

DRUGIBRANCE 100 mg film-coated tablets

Eligibility

Sex/Gender

All

Age

18 Years to No maximum

Design outcomes

Primary

Measure	Time frame
1. Progression-free survival (PFS	—

Secondary

Measure	Time frame
1. Overall survival (OS), 2. Objective response rate (ORR), 3. Duration of response (DOR), 4. Clinical benefit rate (CBR), 5. Time to confirmed deterioration (TTCD) in pain level, 6. TTCD in pain presence and interference, 7. TTCD in physical functioning (PF), 8. TTCD in role functioning (RF), 9. TTCD in global health status (GHS) and quality-of-life (QoL), 10. Incidence and severity of adverse events, with severity determined according to National Cancer Institute (NCI) Common Terminology Criteria for Adverse Events, Version 5.0 (CTCAE v5.0), 11. Change from baseline in targeted vital signs, 12. Plasma concentration of GDC-9545 at specified timepoints, 13. Plasma concentration of palbociclib at specified timepoints	—

Measure

Time frame

—

Countries

Austria, Belgium, Denmark, France, Germany, Greece, Hungary, Italy, Poland, Portugal, Spain

Outcome results

None listed

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