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Recruiting Phase 1 NCT05508906

NCT05508906 Phase 1b Study of OP-1250 (Palazestrant) in Combination With Ribociclib, Alpelisib, Everolimus, or Atirmociclib in ER+, HER2- Breast Cancer

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Clinical Trial Summary
NCT ID NCT05508906
Status Recruiting
Phase Phase 1
Sponsor Olema Pharmaceuticals, Inc.
Condition Metastatic Breast Cancer
Study Type INTERVENTIONAL
Enrollment 190 participants
Start Date 2022-08-31
Primary Completion 2027-12-31

Eligibility & Interventions

Sex All sexes
Min Age 18 Years
Max Age N/A
Study Type INTERVENTIONAL
Interventions
PalazestrantRibociclibAlpelisib

Eligibility Fast-Check

Enter your details for a quick preliminary check. This does not replace medical advice.

What to Expect as a Participant

You will actively receive the study intervention — which may be a drug, biologic, device, or procedure.

Phase 1 is the earliest stage of human testing — safety and dosage are the primary focus. Visits are frequent and medical supervision is intensive. You will be among the first people to receive this treatment.

This trial targets 190 participants in total. It began in 2022-08-31 with a primary completion date of 2027-12-31.

⚠ This information is for research awareness only. Always consult your physician before joining any clinical trial. Participation is voluntary and you may withdraw at any time.

Brief Summary

This is a Phase 1b open-label, 2-part study in 3 treatment groups. The 3 treatment groups are as follows: Treatment Group 1: Palazestrant (OP-1250) in combination with ribociclib (KISQALI®, Novartis Pharmaceuticals Corporation). Treatment Group 2: Palazestrant (OP-1250) in combination with alpelisib (PIQRAY®, Novartis Pharmaceuticals Corporation). Treatment Group 3: Palazestrant (OP-1250) in combination with everolimus. Treatment Group 4: Palazestrant (OP-1250) in combination with atirmociclib.

Eligibility Criteria

Inclusion Criteria: * Female or male aged \>18 years. * Willing and able to participate and comply with all study requirements. * Histologically- or cytologically-confirmed advanced or metastatic Breast Cancer (mBC). * ER+/HER2- disease, as determined in the most recently obtained archival tumor tissue sample from a metastatic site, using locally accepted criteria by the local pathology report. * Evaluable disease with one of the following: Measurable disease, ie, at least 1 measurable lesion as per RECIST 1.1 (a lesion at a previously irradiated site may only be counted as a target lesion if there is clear sign of progression since the irradiation) OR patients with predominantly bone disease (with or without other non-measurable lesions) are allowed if it is possible to evaluate on radiological examinations (eg. bone scan, PET/CT, CT, MRI) even if lesions are non-measurable according to RECIST 1.1. * Life expectancy ≥6 months, as judged by the investigator. * Eastern Cooperative Oncology Group (ECOG) performance status (PS) of 0 or 1. * Has received no more than 1 prior hormonal regimen (Treatment Group 1). Has received no more than 2 prior hormonal regimens (Treatment Group 2 and Treatment Group 3) . Has received no more than 2 prior hormonal regimens for metastatic disease in Part 1 (Dose Escalation) and no more than 1 prior hormonal regimes in Part 2 (Dose Expansion) for metastatic disease, regardless of type of endocrine agent (Treatment Group 4) for advanced or metastatic disease. Prior hormonal regimens in combination with CDK4/6 inhibitors are allowed in all treatment groups. For subjects in Treatment Group 4, no prior chemotherapy for metastatic breast cancer is allowed. * Has received no more than 1 prior chemotherapy (which includes antibody drug conjugates) for locally advanced or metastatic breast cancer. Exclusion Criteria: * Prior or concurrent malignancy whose natural history or treatment may interfere with the safety or efficacy assessment of the investigational regimen. * Clinically significant, uncontrolled heart disease and/or cardiac repolarization abnormality. * History of cerebral vascular disease within 6 months prior to the first administration of study drug dose. * History of a pulmonary embolism, or deep venous thrombosis within the last 6 months, or subject has an increased risk of thrombosis as determined by the investigator. * History of pneumonitis or interstitial lung disease. * Leptomeningeal disease or spinal cord compression. * Medical history or ongoing gastrointestinal disorders that could affect absorption of oral therapeutics. * Known human immunodeficiency virus infection. * Known clinically significant history of liver disease consistent with Child-Pugh Class B or C, including active viral or other hepatitis (eg, hepatitis B or hepatitis C virus), current alcohol abuse, or cirrhosis. * History of severe cutaneous reaction, such as Stevens-Johnson syndrome, erythema multiforme, toxic epidermal necrolysis, or drug reaction with eosinophilia and systemic symptoms. * Active infection or at a high risk of developing a serious infection (e.g. participants with immunodeficiencies, uncontrolled diabetes mellitus, uncontrolled heart disease, poor general health, poor nutritional status). * Has clinically significant co-morbidities, such as, psychiatric disease, or any other condition that could impact the ability of the subject to participate in this study or otherwise has the potential to confound the study results. * Have received prior treatment with OP-1250. * Have received prior treatment with approved or investigational PI3K inhibitor (Treatment Group 2) or mTOR inhibitor (Treatment Group 3).

Contact & Investigator

Central Contact

OP-1250-003 Study

✉ medinfo@olema.com

📞 415 651 7206

Principal Investigator

Daniela Vecchio, PhD

STUDY DIRECTOR

Olema Pharmaceuticals, Inc.

Frequently Asked Questions

Who can join the NCT05508906 clinical trial?

This trial is open to participants of all sexes, aged 18 Years or older, studying Metastatic Breast Cancer. Full inclusion and exclusion criteria are listed in the Eligibility Criteria section. Always confirm your eligibility with the research team before applying.

What phase is the NCT05508906 trial and what does that mean for participants?

Phase 1 trials are the first stage of human testing. The primary goal is to assess safety and determine appropriate dosage levels. Participants are closely monitored. These trials typically involve a small number of volunteers.

Is NCT05508906 currently recruiting?

Yes, NCT05508906 is actively recruiting participants. Contact the research team at medinfo@olema.com for enrollment information.

Where is the NCT05508906 trial being conducted?

This trial is being conducted at Gilbert, United States, San Francisco, United States, Aurora, United States, Orlando, United States and 11 additional locations.

Who is sponsoring the NCT05508906 clinical trial?

NCT05508906 is sponsored by Olema Pharmaceuticals, Inc.. The principal investigator is Daniela Vecchio, PhD at Olema Pharmaceuticals, Inc.. The trial plans to enroll 190 participants.

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ClinicalMetric — Independent clinical trial intelligence platform. Not affiliated with NIH, ClinicalTrials.gov, the U.S. FDA, or any pharmaceutical company, hospital, or clinical research organization. Trial data is sourced from ClinicalTrials.gov for informational purposes only and does not constitute medical advice. Do not make any treatment, enrollment, or health decisions based solely on information found here — always consult a qualified healthcare professional. Full Disclaimer  ·  Last Reviewed: July 2026  ·  Data Methodology