A Phase 1 Study of Oral OP-1250 in Combination With Palbociclib in HR+/HER2- Breast Cancer Patients
![]() |
The safety and scientific validity of this study is the responsibility of the study sponsor and investigators. Listing a study does not mean it has been evaluated by the U.S. Federal Government. Know the risks and potential benefits of clinical studies and talk to your health care provider before participating. Read our disclaimer for details. |
ClinicalTrials.gov Identifier: NCT05266105 |
Recruitment Status :
Recruiting
First Posted : March 4, 2022
Last Update Posted : March 4, 2022
|
- Study Details
- Tabular View
- No Results Posted
- Disclaimer
- How to Read a Study Record
Condition or disease | Intervention/treatment | Phase |
---|---|---|
Breast Cancer | Drug: OP-1250 Drug: Palbociclib | Phase 1 |
Study Type : | Interventional (Clinical Trial) |
Estimated Enrollment : | 30 participants |
Allocation: | Non-Randomized |
Intervention Model: | Sequential Assignment |
Masking: | None (Open Label) |
Primary Purpose: | Treatment |
Official Title: | A Phase 1 Dose Escalation and Expansion Open-label, Multicenter, Study of OP-1250 in Combination With the CDK4/6 Inhibitor Palbociclib in Adult Subjects With Advanced or Metastatic HR-positive, HER2-negative Breast Cancer |
Actual Study Start Date : | December 10, 2021 |
Estimated Primary Completion Date : | January 2023 |
Estimated Study Completion Date : | December 2023 |

Arm | Intervention/treatment |
---|---|
Experimental: Dose Escalation
This portion of the study will evaluate the safety and pharmacology of a range of OP-1250 doses administered daily with Palbociclib in subjects with advanced and/or metastatic hormone receptor (HR)-positive, HER2-negative breast cancer
|
Drug: OP-1250
Complete Estrogen Receptor Antagonist Drug: Palbociclib Palbociclib is an approved CDK 4/6 Inhibitor drug
Other Name: Ibrance®️ |
Experimental: Dose Expansion
This portion of the study further explores the clinical activity, safety and pharmacology of OP-1250 in combination with Palbociclib and estimates preliminary data of anti-tumor efficacy
|
Drug: OP-1250
Complete Estrogen Receptor Antagonist Drug: Palbociclib Palbociclib is an approved CDK 4/6 Inhibitor drug
Other Name: Ibrance®️ |
- Incidence of Dose Limiting Toxicities [ Time Frame: From Cycle 1 Day 1 through C1 Day 28 ]
- Characterization and Incidence in Adverse Events and Serious Adverse Events [ Time Frame: From initial inform consent date through 30 days post last dose ]
- Plasma levels of OP-1250 and Palbociclib [ Time Frame: Up to 9 months ]

Choosing to participate in a study is an important personal decision. Talk with your doctor and family members or friends about deciding to join a study. To learn more about this study, you or your doctor may contact the study research staff using the contacts provided below. For general information, Learn About Clinical Studies.
Ages Eligible for Study: | 18 Years and older (Adult, Older Adult) |
Sexes Eligible for Study: | All |
Accepts Healthy Volunteers: | No |
Inclusion Criteria:
- Confirmed and evaluable locally advanced or metastatic breast cancer
- Eastern Cooperative Oncology Group (ECOG) performance status of 0 or 1
- Must not have received prior oral endocrine or targeted therapy ≤ 2 weeks prior to first dose
- Must not have received prior chemotherapy, antibody therapy, or investigational therapy ≤ 4 weeks prior to the first dose
- Prior radiotherapy must have been completed 2 weeks prior to first dose
- Adequate safety laboratory tests
- Willingness to use effective contraception
Exclusion Criteria:
- Gastrointestinal disease
- Significant hepatic disease
- Significant cardiovascular disease
- Significant ECG abnormalities
- History of pulmonary embolism or high risk of thrombosis
- Known HIV infection
- Active infection (requiring antimicrobial therapy)
- Pregnant

To learn more about this study, you or your doctor may contact the study research staff using the contact information provided by the sponsor.
Please refer to this study by its ClinicalTrials.gov identifier (NCT number): NCT05266105
Contact: General Contact Info | 415-651-7206 | clinical@olema.com |
Australia, New South Wales | |
Site 6104 | Not yet recruiting |
Westmead, New South Wales, Australia, 2145 | |
Australia, Queensland | |
Site 6102 | Recruiting |
South Brisbane, Queensland, Australia, 4101 | |
Australia, Victoria | |
Site 6101 | Recruiting |
Clayton, Victoria, Australia, 3168 | |
Site 6103 | Recruiting |
Geelong, Victoria, Australia, 3220 | |
Australia, Western Australia | |
Site 6105 | Recruiting |
Nedlands, Western Australia, Australia, 6009 |
Study Director: | Sue Johnson | Olema Pharmaceuticals, Inc. |
Responsible Party: | Olema Pharmaceuticals, Inc. |
ClinicalTrials.gov Identifier: | NCT05266105 |
Other Study ID Numbers: |
OP-1250-002 |
First Posted: | March 4, 2022 Key Record Dates |
Last Update Posted: | March 4, 2022 |
Last Verified: | February 2022 |
Individual Participant Data (IPD) Sharing Statement: | |
Plan to Share IPD: | No |
Studies a U.S. FDA-regulated Drug Product: | Yes |
Studies a U.S. FDA-regulated Device Product: | No |
Product Manufactured in and Exported from the U.S.: | Yes |
Breast Neoplasms Neoplasms by Site Neoplasms Breast Diseases Skin Diseases |
Palbociclib Antineoplastic Agents Protein Kinase Inhibitors Enzyme Inhibitors Molecular Mechanisms of Pharmacological Action |