NCT04923542

Stereotactic Radiation & Abemaciclib in the Management of HR+/HER2- Breast Cancer Brain Metastases

Phase I/II Study of Stereotactic Radiation and Abemaciclib in the Management of Hormone Receptor Positive HER2 Negative Breast Cancer Brain Metastases

• Status: Recruiting
• Phase: Phase 1 / Phase 2
• Study type: Interventional
• Enrollment: 31 (estimated)
• Sponsor: H. Lee Moffitt Cancer Center and Research Institute · Academic / Other
• Sex: All
• Age: 18 Years
• Healthy volunteers: Not accepted

Summary

This is a single arm study of abemaciclib and endocrine therapy with stereotactic radiosurgery (SRS) among patients with hormone receptor (HR)+/HER2- metastatic breast cancer brain metastases.

Detailed description

The study is designed as a prospective, single-arm, nonrandomized, open-label, phase I/II trial of abemaciclib and endocrine therapy with stereotactic radiosurgery (SRS) among patients with hormone receptor (HR)+/HER2- metastatic breast cancer brain metastases. Treatment will be initiated with one week of abemaciclib followed by stereotactic radiation to sites of brain metastases or post-operative cavities with continued abemaciclib. Safety will be monitored initially by a 3+3 design. This will be followed by a phase 2 study to evaluate intracranial progression free survival (PFS). If unexpected neurologic toxicities are noted, the dose of radiation therapy will be modified.

Conditions

• Brain Metastases
• HR+ Metastatic Breast Cancer

Interventions

Type	Name	Description
RADIATION	Stereotactic Radiosurgery (SRS)	Patients will receive single session SRS to intact brain metastases and post-operative cavities. For intact brain metastases, this will be 15 Gy to lesions between 31-40 mm, 18 Gy to 21- 30 mm, and 24 Gy to lesions measuring ≤ 20 mm.
DRUG	Abemaciclib	Abemaciclib is an orally administered selective small-molecule inhibitor of CDK4 and CDK6 that is 14 times more potent against CDK4 than CDK6 in enzymatic assays that is approved for the treatment of advanced or metastatic breast cancers. Abemaciclib will be administered at a dose of 150 mg twice daily.
DRUG	Endocrine therapy	Abemaciclib will be administered with standard of care endocrine therapy. Endocrine therapy can consist of fulvestrant or an aromatase inhibitor. Dosing of concurrent endocrine therapy with abemaciclib should follow standard dosing and safety guidelines.

Timeline

• Start date: 2021-11-30
• Primary completion: 2026-11-05
• Completion: 2026-12-01
• First posted: 2021-06-11
• Last updated: 2026-02-06

Locations

2 sites across 1 country: United States

Regulatory

• FDA-regulated drug study