NCT02586675

TEEL Study- Phase 1 Tamoxifen and Ribociclib (LEE011) in Advanced ER+ (HER2 Negative) Breast Cancer

Completed Phase 1 Results posted Last updated 21 January 2022

What this trial tests

Phase 1 trial testing Tamoxifen in Breast Cancer in 7 participants. Completed in 27 October 2021.

Timeline

23 February 2016

Primary endpoint
8 May 2017

27 October 2021

Quick facts

Lead sponsor	H. Lee Moffitt Cancer Center and Research Institute
Phase	Phase 1
Status	Completed
Study type	INTERVENTIONAL
Allocation	na
Design	single group
Masking	none
Primary purpose	treatment
Enrollment	7
Start date	23 February 2016
Primary completion	8 May 2017
Estimated completion	27 October 2021
Sites	1 location across United States

Drugs / interventions tested

• Tamoxifen — full drug profile →
• Ribociclib (ribociclib) — full drug profile →
• Goserelin (goserelin) — full drug profile →

Conditions studied

• Breast Cancer — all drugs for Breast Cancer →
• Breast Cancer - Female — all drugs for Breast Cancer - Female →
• Breast Cancer - Male — all drugs for Breast Cancer - Male →

Sponsor

H. Lee Moffitt Cancer Center and Research Institute

Who can join

18 and older, any sex, with Breast Cancer or Breast Cancer - Female. Patients with the condition only — healthy volunteers not accepted.

Results — posted to ClinicalTrials.gov

Per-arm endpoint measurements with 95% confidence intervals where reported. Source: trial results section.

Recommended Phase II Dose (RP2D) Primary · Up to 12 months

400-600 mg of Ribociclib, when taken with Tamoxifen 20 mg. The Phase I portion of the study is a dose escalation to confirm the dose limiting toxicity (DLT) and the RP2D for ribociclib with Tamoxifen. DLT is defined as an adverse event or abnormal laboratory value assessed as having a reasonable possibility related to the study medication, unrelated to disease, disease progression, inter-current illness, or concomitant medications that occurs within the first 28 days of treatment (cycle 1) with LEE011 and Tamoxifen. National Cancer Institute Common Terminology Criteria for Adverse events (NCI

Group	Value	95% CI
Tamoxifen and Ribociclib With Goserelin	400

Progression-free Survival (PFS) at Six Months Secondary · 6 months

Occurrence of Progression Survival at 6 months. PFS: On study date to date of progression or the same as overall survival time if not progressed. Progressive Disease (PD): At least a 20% increase in the sum of the longest diameter (LD) of target lesions, taking as reference the smallest sum LD recorded since the treatment started or the appearance of one or more new lesions.

Group	Value	95% CI
Tamoxifen and Ribociclib With Goserelin	57.1	17.2 – 83.7

Overall Survival (OS) at Six Months Secondary · 6 months

Occurrence of Overall Survival at 6 months. OS: On study date to expired date or last visit date if not deceased.

Group	Value	95% CI
Tamoxifen and Ribociclib With Goserelin	83.3	27.3 – 97.5

Adverse events — posted to ClinicalTrials.gov

Time frame: 1 year, 2 months. Reporting threshold: 0%. Adverse-event reports describe events observed during the trial — not all are caused by the drug.

Tamoxifen and Ribociclib With Goserelin

Serious: 2/7 (29%)

Deaths: 0/7

Serious adverse events (4 terms)

Reaction	System	Tamoxifen and Ribociclib W…
Gastrointestinal - Other, Gastroenteritis	Gastrointestinal disorders	—
Fatigue	General disorders	—
Syncope	Nervous system disorders	—
Thromboembolic event	Vascular disorders	—

Other adverse events (52 terms — click to expand)

Reaction	System	Tamoxifen and Ribociclib W…
Neutrophil count decreased	Investigations	—
White blood cell decreased	Investigations	—
Alanine aminotransferase increased	Investigations	—
Aspartate aminotransferase increased	Investigations	—
Platelet count decreased	Investigations	—
Dehydration	Metabolism and nutrition disorders	—
Electrocardiogram QT corrected interval prolonged	Investigations	—
Hypomagnesemia	Metabolism and nutrition disorders	—
Dizziness	Nervous system disorders	—
Vomiting	Gastrointestinal disorders	—
Pain	General disorders	—
Alkaline phosphatase increased	Investigations	—
Cholesterol high	Investigations	—
Creatinine increased	Investigations	—
Weight loss	Investigations	—
Anorexia	Metabolism and nutrition disorders	—
Hypokalemia	Metabolism and nutrition disorders	—
Hypophosphatemia	Metabolism and nutrition disorders	—
Dysgeusia	Nervous system disorders	—
Neuralgia	Nervous system disorders	—
Syncope	Nervous system disorders	—
Constipation	Gastrointestinal disorders	—
Diarrhea	Gastrointestinal disorders	—
Dyspepsia	Gastrointestinal disorders	—
Flatulence	Gastrointestinal disorders	—
Mucositis oral	Gastrointestinal disorders	—
Non-cardiac chest pain	General disorders	—
Otitis media	Infections and infestations	—
Sinusitis	Infections and infestations	—
Upper respiratory infection	Infections and infestations	—
Urinary tract infection	Infections and infestations	—
Arthralgia	Musculoskeletal and connective tissue disorders	—
Back pain	Musculoskeletal and connective tissue disorders	—
Bone pain	Musculoskeletal and connective tissue disorders	—
Flank pain	Musculoskeletal and connective tissue disorders	—
Generalized muscle weakness	Musculoskeletal and connective tissue disorders	—
Myalgia	Musculoskeletal and connective tissue disorders	—
Cardiac disorders - Other, T Wave Inversion, Q Wave in II, on EKG	Cardiac disorders	—
Chest pain - cardiac	Cardiac disorders	—
Sinus bradycardia	Cardiac disorders	—

Most-reported serious reactions: Gastrointestinal - Other, Gastroenteritis, Fatigue, Syncope, Thromboembolic event.

Data from ClinicalTrials.gov NCT02586675 adverse events section.

Sponsor's own description

The purpose of this study is to find out if the investigational drug Ribociclib (LEE011), when taken with standard treatment (Tamoxifen +/- Goserelin) is safe and has beneficial effects in pre-menopausal and post-menopausal women and men who have a type of breast cancer known as hormone receptor positive/HER2- breast cancer.

Publications & conference data

8 peer-reviewed publications reference this trial (live from Europe PMC):

1. Cyclin D1, cancer progression, and opportunities in cancer treatment.
   Qie S, Diehl JA. · · 2016 · cited 527× · PMID 27695879 · DOI 10.1007/s00109-016-1475-3
2. CDK4/6 Inhibitors: The Mechanism of Action May Not Be as Simple as Once Thought.
   Klein ME, Kovatcheva M, Davis LE, Tap WD, et al · · 2018 · cited 308× · PMID 29731395 · DOI 10.1016/j.ccell.2018.03.023
3. The Strange Case of CDK4/6 Inhibitors: Mechanisms, Resistance, and Combination Strategies.
   Knudsen ES, Witkiewicz AK. · · 2017 · cited 218× · PMID 28303264 · DOI 10.1016/j.trecan.2016.11.006
4. Transcription Factors in Cancer Development and Therapy.
   Vishnoi K, Viswakarma N, Rana A, Rana B. · · 2020 · cited 123× · PMID 32824207 · DOI 10.3390/cancers12082296
5. Investigational chemotherapy and novel pharmacokinetic mechanisms for the treatment of breast cancer brain metastases.
   Shah N, Mohammad AS, Saralkar P, Sprowls SA, et al · · 2018 · cited 102× · PMID 29604436 · DOI 10.1016/j.phrs.2018.03.021
6. Mechanisms of resistance to estrogen receptor modulators in ER+/HER2- advanced breast cancer.
   Zhang J, Wang Q, Wang Q, Cao J, et al · · 2020 · cited 25× · PMID 31471681 · DOI 10.1007/s00018-019-03281-4
7. Targeting Breast Cancer: The Familiar, the Emerging, and the Uncharted Territories.
   Montazeri Aliabadi H, Manda A, Sidgal R, Chung C. · · 2023 · cited 6× · PMID 37759706 · DOI 10.3390/biom13091306
8. Unusual presentation of luminal breast carcinoma metastatic to the brain and coma: a case report of dramatic response to abemaciclib and literature review.
   Valerio MR, Cipolla C, Greco M, Mesi C, et al · · 2025 · PMID 40162001 · DOI 10.1177/17588359251317847