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Taking people in CanadaPhase 3

Tests palazestrant with ribociclib in adults with advanced ER-positive breast cancer

Tests palazestrant with ribociclib against letrozole with ribociclib in adults with advanced breast cancer.

Plain-language title generated from the registry record
Registry title: Palazestrant in Combination With Ribociclib for the First-line Treatment of ER+/HER2- Advanced Breast Cancer

Key facts

Where
Greenfield Park and Toronto, CanadaSee the 2 sites
Phase
Phase 3

Could this be for you?

Answer for yourself. This is not a decision: only the study team can say whether you can take part.

  • What did the tests on your tumour show about hormone receptors and the HER2 protein?
  • Have you already had any medicine for your cancer after it spread or became advanced?
  • Have you had chemotherapy for cancer that has spread or is advanced?

Source: NCT07085767, who can take part

Where in Canada

  • Greenfield ParkGreenfield Park, CanadaTaking people
  • TorontoToronto, CanadaTaking people

Questions to ask the study team

  1. How often do I need to come in, and for how long each time?
  2. Are travel costs paid?
  3. Can I keep my own doctor?
  4. What happens if I want to stop?
Print a page for my doctor

Trial details

Who runs it
Olema Pharmaceuticals, Inc.
Trial code
NCT07085767EU 2025-522873-12-00
Record updated
23 September 2026
Original 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.Read full original descriptionShow less

A Phase 3 Randomized, Double-Blind, Active-Controlled Study of Palazestrant With Ribociclib Versus Letrozole With Ribociclib for the First-Line Treatment of ER+, HER2- Advanced Breast Cancer (OPERA-02)

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.

Inclusion: 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: 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; Disease recurrence during adjuvant endocrine therapy; History of allergic reactions to study treatment; Symptomatic central nervous system metastases, carcinomatous meningitis, leptomeningeal disease, or a spinal cord compression that require immediate treatment; Any contraindications to letrozole and ribociclib.

ClinicalTrials.gov NCT07085767 · EU CTIS 2025-522873-12-00