Palazestrant in Combination With Ribociclib for the First-line Treatment of ER+/HER2- Advanced Breast Cancer

Conditions

• Breast Cancer
• ER Positive Breast Cancer
• HER2 Negative Breast Carcinoma
• Locally Advanced Breast Cancer
• Metastatic Breast Cancer

Eligibility Criteria

Sex

ALL

Age

18 Years - N/A

Healthy Volunteers

Not accepted

Interventions

• Palazestrant — DRUG
  Participants will be treated with palazestrant 90 mg once daily on a 4-week (28-day) cycle.
• Letrozole-matching placebo — DRUG
  Participants will be treated with letrozole-matching placebo once daily on a 4-week (28 day) cycle
• Ribociclib — DRUG
  Participants will be treated with ribociclib 600 mg once daily on Days 1-21 of a 4-week (28 day) cycle.
• Letrozole — DRUG
  Participants will be treated with letrozole 2.5 mg once daily on a 4-week (28-day) cycle
• Palazestrant matching-placebo — DRUG
  Participants will be treated with palazestrant-matching placebo once daily on a 4-week (28-day) cycle

Study Details

This phase 3 clinical trial compares the efficacy and safety of palazestrant with ribociclib to letrozole and ribociclib in women and men who have not received prior systemic anti-cancer treatment for advanced breast cancer.

Key Dates

Start date

Nov 3, 2025

Status verified

May 2026

Primary completion

Dec 31, 2028

Completion

Jan 31, 2032

Study Design

Enrollment

1,000 participants (estimated)

Allocation

RANDOMIZED

Intervention model

PARALLEL

Primary purpose

TREATMENT

Arms

• Experimental: Palazestrant
  Participants will receive palazestrant, ribociclib and letrozole-matching placebo
• Active Comparator: Letrozole
  Participants will receive letrozole, ribociclib and palazestrant-matching placebo

Primary Outcome Measure

Progression-Free Survival (PFS) [ Time Frame: From Date of Randomization until Disease Progression or Death Due to Any Cause (estimated as up to 3.5 years) ]

Central Contacts

• Olema Pharmaceuticals, Inc.
  415-651-7206
  [email protected]

Locations (28)

Find similar trials in Hot Springs, AR

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