NCT07085767 · Olema Pharmaceuticals, Inc.
Palazestrant in Combination With Ribociclib for the First-line Treatment of ER+/HER2- Advanced Breast Cancer
(OPERA-02)
What this study is about
This phase 3 clinical trial compares the effectiveness 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.
View original scientific description
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.
Who can participate
This study lists these criteria on ClinicalTrials.gov. A study coordinator reviews eligibility during screening — this page does not determine whether you qualify.
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
- Hot Springs, Arkansas
- Beverly Hills, California
- San Francisco, California
- Santa Barbara, California
- Aurora, Colorado
- Denver, Colorado
- New Haven, Connecticut
- Tampa, Florida
- Marietta, Georgia
- Honolulu, Hawaii
- Peoria, Illinois
- Urbana, Illinois
And 25 more locations — see the full list below.
Frequently asked questions
What is a clinical trial?
A clinical trial is a research study that tests new medical treatments, drugs, devices, or procedures to determine their safety and effectiveness. Trials are carefully designed and monitored to protect participants while advancing medical knowledge.
Is it safe to participate?
Clinical trials follow strict safety guidelines and ethical standards. Trials must be reviewed and approved, and participants are closely monitored by medical professionals throughout the study. You can withdraw at any time if you choose.
Will I be compensated?
Many clinical trials offer compensation for your time, travel expenses, and inconvenience. The specific compensation varies by study and will be discussed during the screening process. All study-related medical care is typically provided at no cost to participants.
Will I receive a placebo instead of treatment?
When effective treatment exists, participants typically receive either the standard treatment plus the study intervention, or the standard treatment plus placebo. You would not be denied effective care. Placebos are primarily used when no proven treatment is available, or in addition to standard care. Your trial consent form will clearly explain what treatments you may receive.
Can I leave a trial if I change my mind?
Absolutely. Participation in clinical trials is completely voluntary. You have the right to withdraw from the study at any time, for any reason, without penalty or loss of benefits to which you are otherwise entitled.
How long does a clinical trial last?
Trial duration varies widely depending on the study design and purpose. Some trials last just a few weeks, while others may continue for months or years. The study coordinator will provide specific timeline information during your screening call.
Data: ClinicalTrials.gov · synced Jun 16, 2026 · Source of record for eligibility and locations