Abemaciclib in Treating Patients With Advanced, Refractory, and Unresectable Digestive System Neuroendocrine Tumors

Study Purpose

This phase II trial studies how well abemaciclib works in treating patients with digestive system neuroendocrine tumors that have spread to other places in the body, do not respond to treatment, and cannot be removed by surgery. Abemaciclib may stop the growth of tumor cells by blocking some of the enzymes needed for cell growth.

Recruitment Criteria

Accepts Healthy Volunteers

Healthy volunteers are participants who do not have a disease or condition, or related conditions or symptoms

Study Type

An interventional clinical study is where participants are assigned to receive one or more interventions (or no intervention) so that researchers can evaluate the effects of the interventions on biomedical or health-related outcomes.

An observational clinical study is where participants identified as belonging to study groups are assessed for biomedical or health outcomes.

Searching Both is inclusive of interventional and observational studies.

Eligible Ages 18 Years and Over
Gender All
More Inclusion & Exclusion Criteria

Inclusion Criteria:

  • - Histologically confirmed GEP NET, radiographically progressed on at least one line of standard therapy within the past 12 months.
  • - Primary tumors may be in: pancreas, foregut (esophagus, stomach, duodenum), midgut (small intestine, appendix), hindgut (large intestine, rectum), or unknown origin.
  • - Tumors may be functional (associated with clinical symptoms of hormone secretion) or non-functional.
  • - Well-differentiated NET with low grade (Ki67 index < 3% or mitotic index < 2 mitoses/10 high power field [HPF]), intermediate grade (Ki67 index 3-20% or mitotic index 2-20 mitoses/10 HPF), or high grade (Ki67 21% to ≤ 55% of mitotic index 21-55% mitoses/10 HPF).
In cases where pathology reports call out only a "high grade neuroendocrine carcinoma", such patients are eligible only if well differentiated status is confirmed by a board-certified pathologist AND Ki-67 is ≤ 55%
  • - Metastatic or locally advanced unresectable disease.
  • - Measurable disease by computed tomography (CT) or magnetic resonance imaging (MRI) as per Response Evaluation Criteria in Solid Tumors (RECIST) version (v) 1.1.
  • - Prior or concurrent therapy with somatostatin analogs (SSAs) is allowed.
If concurrent therapy, dose must be stable for at least 2 months.
  • - Patients with carcinoid syndrome must have symptoms controlled with stable doses of SSAs for at least 2 months.
* Telotristat is not allowed.
  • - Age >= 18 years.
  • - Eastern Cooperative Oncology Group (ECOG) performance status of 0 to 2.
  • - Able to swallow oral medications.
  • - Absolute neutrophil count >= 1500/uL.
  • - Platelet count >= 100,000/uL (without platelet transfusion for at least two weeks) - Hemoglobin >= 8 g/dL (blood transfusion is not allowed the day before or on the day of study treatment) - Total bilirubin =< 1.5 times upper limit of normal (ULN) - Transaminases (aspartate aminotransferase [AST] and/or alanine aminotransferase [ALT]) =< 3 x upper limit of normal (ULN) (=< 5 x ULN if liver metastases) - Patients with Gilbert's syndrome with a total bilirubin =< 2.0 times ULN and direct bilirubin within normal limits are permitted.
  • - International normalized ratio (INR) and partial thromboplastin time (PTT) =< 1.5 x ULN.
  • - Creatinine > 30 mL/min.
  • - Ability to understand and sign the consent form.
  • - Women of child-bearing potential must: - Have a negative serum pregnancy test within 7 days prior to initiation of treatment, and.
  • - Agree to use a highly effective method of contraception during the study and for at least 3 weeks following the last dose of study drug.
  • - Men must be sterile or agree to use a highly effective method of contraception during the study and for at least 3 weeks following the last dose of study drug.

Exclusion Criteria:

  • - Presence of poorly differentiated neuroendocrine carcinoma (NEC) or mixed adenoneuroendocrine carcinomas (MANECs) - Prior treatment with abemaciclib or other CDK4/6 inhibitors.
  • - Known hypersensitivity to abemaciclib or its components.
  • - Receipt of any therapy or investigational agent within 4 weeks prior to study registration, except SSAs.
  • - Any surgery, radiation, or embolization within 4 weeks.
  • - Peptide receptor radionuclide therapy (PRRT) within 6 weeks.
  • - Patients receiving other investigational agents.
  • - Patients who have not recovered from adverse events of prior therapy to =< grade 1 (National Cancer Institute [NCI] Common Terminology Criteria for Adverse Events [CTCAE] version [v] 5), except for alopecia or grade =< 2 peripheral neuropathy prior to study treatment initiation.
Subjects must have fully recovered from the acute effects of any prior radiotherapy.
  • - Patients with untreated or symptomatic brain metastases (must be off corticosteroids for >= 4 weeks) - Uncontrolled or untreated intercurrent illness including, but not limited to, active bacterial or fungal infection, congestive heart failure, severe/unstable angina, syncope of cardiac etiology, ventricular arrythmia (including but not limited to ventricular tachycardia, ventricular fibrillation), history of cardiac arrest, interstitial lung disease, severe dyspnea at rest or requiring oxygen supplementation, arterial or venous thrombotic event, pre-existing chronic condition resulting in baseline grade >= 2 diarrhea, or psychiatric illness/social situations that would limit compliance with study requirements.
  • - Gastrointestinal tract disease resulting in an inability to take oral medication or a requirement for intravenous (IV) alimentation, prior surgical procedures involving stomach or small bowel in the last 28 days, active peptic ulcer disease, Crohn's disease or ulcerative colitis.
- Severe renal impairment (e.g. estimated creatinine clearance < 30ml/min) - Known history of infection with human immunodeficiency virus (HIV) - Active untreated infection with hepatitis B virus (i.e. hepatitis B surface antigen positive) or hepatitis C virus (i.e. hepatitis C antibody and ribonucleic acid [RNA] positive) - Other malignancy diagnosed or recurrent in the past 3 years (except non-melanoma skin cancer and in-situ cervical cancer) - Pregnancy or breast-feeding

Trial Details

Trial ID:

This trial id was obtained from ClinicalTrials.gov, a service of the U.S. National Institutes of Health, providing information on publicly and privately supported clinical studies of human participants with locations in all 50 States and in 196 countries.


Phase 1: Studies that emphasize safety and how the drug is metabolized and excreted in humans.

Phase 2: Studies that gather preliminary data on effectiveness (whether the drug works in people who have a certain disease or condition) and additional safety data.

Phase 3: Studies that gather more information about safety and effectiveness by studying different populations and different dosages and by using the drug in combination with other drugs.

Phase 4: Studies occurring after FDA has approved a drug for marketing, efficacy, or optimal use.

Phase 2
Lead Sponsor

The sponsor is the organization or person who oversees the clinical study and is responsible for analyzing the study data.

University of Washington
Principal Investigator

The person who is responsible for the scientific and technical direction of the entire clinical study.

David B. Zhen
Principal Investigator Affiliation Fred Hutch/University of Washington Cancer Consortium
Agency Class

Category of organization(s) involved as sponsor (and collaborator) supporting the trial.

Other, Industry
Overall Status Recruiting
Countries United States

The disease, disorder, syndrome, illness, or injury that is being studied.

Advanced Digestive System Neuroendocrine Neoplasm, Digestive System Neuroendocrine Tumor, Foregut Neuroendocrine Tumor, Hindgut Neuroendocrine Tumor, Locally Advanced Unresectable Digestive System Neuroendocrine Neoplasm, Metastatic Digestive System Neuroendocrine Neoplasm, Midgut Neuroendocrine Tumor, Pancreatic Neuroendocrine Tumor, Refractory Digestive System Neuroendocrine Neoplasm
Additional Details

Patients receive abemaciclib orally (PO) twice daily (BID) on days 1-28. Cycles repeat every 28 days in the absence of disease progression or unacceptable toxicity. After completion of study treatment, patients are followed up at 30 days and then every 4 months for up to 1 year.

Arms & Interventions


Experimental: Treatment (abemaciclib)

Patients receive abemaciclib PO BID on days 1-28. Cycles repeat every 28 days in the absence of disease progression or unacceptable toxicity.


Drug: - Abemaciclib

Given PO

Contact a Trial Team

If you are interested in learning more about this trial, find the trial site nearest to your location and contact the site coordinator via email or phone. We also strongly recommend that you consult with your healthcare provider about the trials that may interest you and refer to our terms of service below.

University of Colorado, Denver, Colorado


Not yet recruiting


University of Colorado

Denver, Colorado, 80217

Site Contact

Stephen Leong



Seattle, Washington




Fred Hutch/University of Washington Cancer Consortium

Seattle, Washington, 98109

Site Contact

David B. Zhen



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