Palazestrant plus ribociclib as first-line treatment for ER+/HER2- advanced breast cancer

Is this trial a fit for you?

A plain-English reading of the study's rules. Only the study team can confirm whether you qualify.

What this trial studies

This is a randomized, double-blind, active-controlled phase 3 trial that will enroll about 1,000 adults with ER+/HER2- locally advanced or metastatic breast cancer and randomize them 1:1. Participants receive either palazestrant plus ribociclib with a letrozole-matching placebo or letrozole plus ribociclib with a palazestrant-matching placebo. The study compares efficacy and safety between the two arms while maintaining blinding with matching placebos. Eligible participants include men and women with measurable or bone-only disease and ECOG performance status 0–1.

Why it matters

Who can join: the full rules

Inclusion Criteria:

* Adult female or male participants.
* ER+, HER2- locally advanced or metastatic breast cancer that is not amenable to curative therapy.
* Evaluable disease (measurable disease per RECIST 1.1 or bone-only disease).
* De novo advanced breast cancer or with disease recurrence occurring after 12 months of completing adjuvant endocrine therapy (with or without CDK4/6 inhibitors)
* Eastern Cooperative Oncology Group (ECOG) performance status of 0 or 1.
* Adequate hematologic, hepatic, and renal functions.
* Female participants can be pre-, peri- or postmenopausal.
* Male and pre- or peri-menopausal female participants must be willing to take a GnRH (or LHRH) agonist.

Exclusion Criteria:

* Disease recurrence during adjuvant endocrine therapy
* Currently receiving or previously received systemic anti-cancer therapy for ER+, HER2- advanced breast cancer.
* Previously received treatment with fulvestrant, elacestrant or an investigational endocrine therapy in any setting.
* History of allergic reactions to study treatment.
* Any contraindications to letrozole and ribociclib.
* Symptomatic central nervous system metastases, carcinomatous meningitis, leptomeningeal disease, or a spinal cord compression that require immediate treatment.

Where it's running

• Clinical Trial Site
  Hot Springs, Arkansas, United States Recruiting
• Clinical Trial Site
  Beverly Hills, California, United States Recruiting
• Clinical Trial Site
  La Jolla, California, United States Recruiting
• Clinical Trial Site
  Los Alamitos, California, United States Recruiting
• Clinical Trial Site
  Oakland, California, United States Recruiting
• Clinical Trial Site
  Roseville, California, United States Recruiting

+150 more sites. See ClinicalTrials.gov for the full list.

Study contacts

• Study coordinator: Olema Pharmaceuticals, Inc.
• Email: OPERA-02@olema.com
• Phone: 415-651-7206

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How to take part

1. Review the eligibility criteria above with your treating physician.
2. Check the official listing on ClinicalTrials.gov for the latest contact details and recruitment status.
3. Contact the study coordinator or principal investigator to ask for pre-screening. Pre-screening is free and never obligates you to enroll.