A Phase 1/2 interventional study of Stereotactic Radiosurgery (SRS) and Abemaciclib in Brain Metastases and HR+ Metastatic Breast Cancer, sponsored by H. Lee Moffitt Cancer Center and Research Institute. Recruiting at 2 sites in United States. Open to participants aged 18 Years and older. Per ClinicalTrials.gov, last updated 2026-09-28.
Sponsored by H. Lee Moffitt Cancer Center and Research Institute · Phase 1/2, Interventional, and Treatment
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.
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.
2,440 studies on the registry are indexed under Brain Neoplasms; 540 are open to participants now.
This study's planned enrollment of 31 is below the median of 40 across 1,831 interventional studies indexed under Brain Neoplasms.
Browse Brain Neoplasms studies →H. Lee Moffitt Cancer Center and Research Institute is the lead sponsor of 540 studies on the registry; 75 are open to participants now.
Of its 99 completed or terminated interventional studies of FDA-regulated products, 57 (58%) have results posted.
Counted across the registry records on this site, refreshed daily.
Go through the criteria one by one — yes, no or not sure — and take the list to your doctor or the study team. Kept in this browser only.
Exclusion Criteria:
Underlined terms in the criteria open these too. Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
HER2 is a protein, made from the ERBB2 gene, that drives the growth of some cancers. A study may look for a level of the protein, extra copies of the gene, or a particular change in it.
In breast cancer, protein tests are read as HER2-positive, HER2-low or HER2-negative; other cancers use their own rules. Check which test result the study requires.
A biopsy takes a small piece of tissue to examine. “Archival tissue” is a sample already taken, for example at diagnosis, and kept by the hospital.
Whether a stored sample will do depends on when it was taken, how much there is and what the study needs. Ask whether the study accepts your stored sample or needs a new biopsy.
Cancer deposits in the brain from a cancer that started elsewhere in the body (CNS metastases include the spinal cord).
Studies differ: some leave out any brain metastases, some accept ones treated and stable for some weeks. Check what this study allows.
A scale of how much an illness limits everyday activity. For people being assessed to join a study, scores run from 0 (fully active) to 4; lower is more active.
Studies most often ask for 0–1 or 0–2. Your doctor gives the score; the WHO scale uses the same steps. The full scale also has 5, which records death.
The amount of disease can be tracked with a defined measurement, so the study can see whether it shrinks or grows. It might be a tumour measured on a scan or, in some blood cancers such as myeloma, a marker measured in blood or urine.
The criteria or the study team say which measurement counts — having no tumour visible on a scan does not by itself rule you out.
Able to become pregnant: from the first period until menopause, unless permanently unable to through surgery (removal of the womb, or of both ovaries or both fallopian tubes).
Criteria for people of childbearing potential usually ask for a negative pregnancy test and for contraception during the study and for a time after it.
Ways of preventing pregnancy. “Highly effective” methods fail less than 1% of the time a year when used correctly — for example an IUD or an implant.
Criteria usually say which methods count and how long to keep using them after the last dose, sometimes for male participants too. Some studies accept a partner’s vasectomy if it was confirmed successful and that person is the participant’s only sexual partner.
Cancer that has spread to the leptomeninges, the thin layers covering the brain and spinal cord, and the fluid between them. It is not the same as brain metastases.
Criteria often treat it separately, and many studies leave it out even where treated brain metastases are allowed.
Cancer that has spread from where it began to other parts of the body. “Metastatic” cancer is cancer that has spread this way.
The US National Cancer Institute’s scale of how severe an adverse event is — any unwanted medical event during a study, such as a symptom, an illness or an abnormal test result, whether or not a treatment caused it. Whether it did is judged separately.
“Side effects of earlier treatment resolved to grade 1 or less” means they have settled to mild or gone.
How quickly the kidneys clear creatinine, a waste product, from the blood. A study may estimate it from a blood test with age, weight and sex (often by the Cockcroft–Gault formula), or measure it using blood and urine collected over a set time. Given in mL/min; higher is better.
The human immunodeficiency virus, which weakens the immune system.
Many studies now accept people whose HIV is controlled on treatment, judged by the viral load and the CD4 count. Check the limits this study sets.
Hepatitis B is a virus that infects the liver. These are separate tests: HBsAg positive usually means a current infection (a recent vaccination can briefly cause it too); total anti-HBc (HBcAb) positive means an infection now or in the past; HBV DNA measures how much virus is in the blood.
Some studies accept a past infection if HBV DNA is undetectable, sometimes with antiviral medicine during the study. Check what this study allows.
Malignancy means cancer. Criteria about another or earlier malignancy ask whether you have had a different cancer, usually within a set number of years.
Some are commonly allowed, such as treated skin cancers other than melanoma and early cancers removed completely — check the exceptions this study lists.
A drug or device being studied in a clinical trial.
It may be new, or already approved and being studied for another use, dose or form. Criteria often leave out people who took part in another study of one within a recent period, commonly 30 days or five half-lives.
An allergy, or another reaction of the immune system, to a substance. “Hypersensitivity to the study drug” means a known allergic reaction to it — not every side effect a medicine can have.
HER2
HER2 is a protein, made from the ERBB2 gene, that drives the growth of some cancers. A study may look for a level of the protein, extra copies of the gene, or a particular change in it.
In breast cancer, protein tests are read as HER2-positive, HER2-low or HER2-negative; other cancers use their own rules. Check which test result the study requires.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Biopsy and archival tissue
A biopsy takes a small piece of tissue to examine. “Archival tissue” is a sample already taken, for example at diagnosis, and kept by the hospital.
Whether a stored sample will do depends on when it was taken, how much there is and what the study needs. Ask whether the study accepts your stored sample or needs a new biopsy.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Brain metastases
Cancer deposits in the brain from a cancer that started elsewhere in the body (CNS metastases include the spinal cord).
Studies differ: some leave out any brain metastases, some accept ones treated and stable for some weeks. Check what this study allows.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
ECOG performance status
A scale of how much an illness limits everyday activity. For people being assessed to join a study, scores run from 0 (fully active) to 4; lower is more active.
Studies most often ask for 0–1 or 0–2. Your doctor gives the score; the WHO scale uses the same steps. The full scale also has 5, which records death.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Measurable disease
The amount of disease can be tracked with a defined measurement, so the study can see whether it shrinks or grows. It might be a tumour measured on a scan or, in some blood cancers such as myeloma, a marker measured in blood or urine.
The criteria or the study team say which measurement counts — having no tumour visible on a scan does not by itself rule you out.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Childbearing potential
Able to become pregnant: from the first period until menopause, unless permanently unable to through surgery (removal of the womb, or of both ovaries or both fallopian tubes).
Criteria for people of childbearing potential usually ask for a negative pregnancy test and for contraception during the study and for a time after it.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Contraception
Ways of preventing pregnancy. “Highly effective” methods fail less than 1% of the time a year when used correctly — for example an IUD or an implant.
Criteria usually say which methods count and how long to keep using them after the last dose, sometimes for male participants too. Some studies accept a partner’s vasectomy if it was confirmed successful and that person is the participant’s only sexual partner.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Leptomeningeal disease
Cancer that has spread to the leptomeninges, the thin layers covering the brain and spinal cord, and the fluid between them. It is not the same as brain metastases.
Criteria often treat it separately, and many studies leave it out even where treated brain metastases are allowed.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Metastases
Cancer that has spread from where it began to other parts of the body. “Metastatic” cancer is cancer that has spread this way.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
CTCAE grade
The US National Cancer Institute’s scale of how severe an adverse event is — any unwanted medical event during a study, such as a symptom, an illness or an abnormal test result, whether or not a treatment caused it. Whether it did is judged separately.
“Side effects of earlier treatment resolved to grade 1 or less” means they have settled to mild or gone.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Creatinine clearance (CrCl)
How quickly the kidneys clear creatinine, a waste product, from the blood. A study may estimate it from a blood test with age, weight and sex (often by the Cockcroft–Gault formula), or measure it using blood and urine collected over a set time. Given in mL/min; higher is better.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
HIV
The human immunodeficiency virus, which weakens the immune system.
Many studies now accept people whose HIV is controlled on treatment, judged by the viral load and the CD4 count. Check the limits this study sets.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Hepatitis B tests
Hepatitis B is a virus that infects the liver. These are separate tests: HBsAg positive usually means a current infection (a recent vaccination can briefly cause it too); total anti-HBc (HBcAb) positive means an infection now or in the past; HBV DNA measures how much virus is in the blood.
Some studies accept a past infection if HBV DNA is undetectable, sometimes with antiviral medicine during the study. Check what this study allows.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Cancer (malignancy)
Malignancy means cancer. Criteria about another or earlier malignancy ask whether you have had a different cancer, usually within a set number of years.
Some are commonly allowed, such as treated skin cancers other than melanoma and early cancers removed completely — check the exceptions this study lists.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Investigational drug or device
A drug or device being studied in a clinical trial.
It may be new, or already approved and being studied for another use, dose or form. Criteria often leave out people who took part in another study of one within a recent period, commonly 30 days or five half-lives.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Hypersensitivity
An allergy, or another reaction of the immune system, to a substance. “Hypersensitivity to the study drug” means a known allergic reaction to it — not every side effect a medicine can have.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
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. In the phase I portion, safety will be monitored initially by a 3+3 design. If unexpected neurologic toxicities are noted, the dose of radiation therapy will be modified.
Radiation: Stereotactic Radiosurgery (SRS) · Drug: Abemaciclib · Drug: Endocrine therapy
Treatment will be initiated with one week of abemaciclib followed by stereotactic radiation at the phase 1 dose to sites of brain metastases or post-operative cavities with continued abemaciclib.
Radiation: Stereotactic Radiosurgery (SRS) · Drug: Abemaciclib · Drug: Endocrine therapy
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.
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.
Also known as: Verzenio, Ramiven
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.
Also known as: hormone therapy
This study also gives Imlunestrant, Fulvestrant. No intervention listed here names it: that was found by reading the record.
Intracranial Progression Free Survival (PFS)
Intracranial Progression Free Survival: defined as the time from the date of start of treatment to investigator-determined date of progression or death due to any cause, whichever comes first. Progression will be determined by Response Assessment in Neuro-Oncology Brain Metastases (RANO-BM) Criteria.
Time frame: Up to 12 months
Intracranial local brain tumor control
Intracranial local brain tumor control following SRS and abemaciclib will be determined from irradiated lesions according to RANO-BM criteria.
Time frame: Up to 12 months
Intracranial distant brain tumor control
Intracranial distant brain tumor control following SRS and abemaciclib will determined by the development of new lesions outside of the irradiated area.
Time frame: Up to 12 months
Extracranial Progression Free Survival
Extracranial Progression Free Survival: Time from the date of start of treatment to the investigator determined date of progression (determined by RECIST) or death due to any cause, whichever occurs first.
Time frame: Up to 12 months
Overall Survival
Overall Survival is defined as the time from the start of treatment to death due to any cause.
Time frame: Up to 12 months
Not enrolling at this site.
Plan to share: No
From the registry record's own update history. This site started tracking changes on Sep 25, 2026; for anything earlier, see the record history on ClinicalTrials.gov ↗
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Studies of the drug tested here: Abemaciclib
H. Lee Moffitt Cancer Center and Research Institute →