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Assessment of Safety and Efficacy of Estetrol in Postmenopausal Women With Advanced Estrogen Receptor Positive (ER+) Breast Cancer

A Phase I/II Clinical Trial Assessing Safety and Efficacy of Estetrol (E4) in Postmenopausal Women With Advanced Estrogen Receptor Positive (ER+) Breast Cancer

Status
Completed
Phases
Phase 1Phase 2
Study type
Interventional
Source
ClinicalTrials.gov
Registry ID
NCT02718144
Enrollment
12
Registered
2016-03-24
Start date
2017-06-01
Completion date
2019-12-31
Last updated
2021-06-18

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Breast Neoplasms

Keywords

dose-escalation, safety, dose-limiting toxicity

Brief summary

This is a multi-center, open-label, phase I/IIa trial, dose-escalation study with a 3 + 3 cohort design to determine the recommended dose of estetrol for the treatment of patients with advanced breast cancer. After completing phase I part of the study (i.e. 4 weeks of treatment), patients will receive further treatment for 8 weeks at their individual phase I dose level (phase IIa part of the study).

Interventions

Estetrol formulated in tablets, in escalating doses, will be investigated in patients with estrogen receptor positive (ER+) locally advanced or metastatic breast cancer.

Sponsors

Pantarhei Oncology B.V.
Lead SponsorOTHER

Study design

Allocation
NA
Intervention model
SINGLE_GROUP
Primary purpose
OTHER
Masking
NONE

Eligibility

Sex/Gender
FEMALE
Healthy volunteers
No

Inclusion criteria

* Postmenopausal women with ER-positive and HER2-negative locally advanced and/or metastatic breast cancer, who progressed on standard therapies or for whom standard therapies are intolerant; * Patients should have experienced a natural or surgical menopause at least 5 years ago; * Failure of anti-estrogen treatment with tamoxifen and aromatase inhibitor(s) due to the development of resistance or unacceptable side effects with this treatment; * No undiagnosed vaginal bleeding; * No treatment with fulvestrant within 6 months of start of treatment; * Life expectancy at least 6 months; * Tumour assessment (CT scan) before the start of the E4 treatment; * Body mass index (BMI) between (≥) 18 and (≤) 35 kg/m2; * Able to swallow an oral medication; * Acceptable values of hematological parameters, liver and kidney function and calcium levels; * Acceptable values of hemostasis parameters (as of second cohort); * Eastern Cooperative Oncology Group (ECOG) Performance Status: 0-2 (as of second cohort); * Reasonable physical and mental health as judged by the investigator and determined by physical examination, clinical laboratory assessments and vital signs; * Willing to give informed consent in writing.

Exclusion criteria

* Uncontrolled nausea, vomiting, or diarrhea; * History of venous or arterial thromboembolic disease or a known defect in the blood coagulation system; * History of severe cardiac events or life threatening cardiac dysrhythmia (as of second cohort); * Patients who have unstable angina or clinical congestive heart failure (as of second cohort); * Uncontrolled hypertension, i.e. systolic blood pressure 160 mmHg and/or diastolic blood pressure 100 mmHg in the last 6 months with or without medication; * Diabetes mellitus with poor glycaemic control in the last 6 months (HbA1c above 7.5%); * Any other serious disease including systemic lupus erythematosus and untreated cholelithiasis; * Smoking \>10 cigarettes/day; * Use of any other cancer therapy including radiotherapy (except for palliative reasons), endocrine therapy, immunotherapy, chemotherapy, or use of other investigational agents at the start of treatment.

Design outcomes

Primary

MeasureTime frame
The number of patients with a dose limiting toxicity (DLT)4 weeks

Secondary

MeasureTime frameDescription
Questionnaire on estrogen deficiency symptoms12 weeksQuality of Life will be assessed by means of a questionnaire on estrogen deficiency symptoms.
Pharmacokinetics: estetrol trough levels2 weeks, 4 weeks, 8 weeks
Preliminary anti-tumour response according to RECIST 1.112 weeks

Other

MeasureTime frame
Number of patients with Adverse Events (AEs)12 weeks

Countries

Germany

Outcome results

None listed

Source: ClinicalTrials.gov · Data processed: Feb 4, 2026