Tamoxifen Citrate in Patients With Breast Cancer
Breast Cancer
Conditions: official terms
Breast Neoplasms
Conditions: Keywords
endocrine sensitive, breast cancer, tamoxifen, genotyping, phenotyping, Pharmacokinetics, Endoxifen
Study Type
Study Phase
Phase 3
Study Design
Intervention Model: Single Group Assignment, Masking: Open Label, Primary Purpose: Treatment
Name: tamoxifen citrate Type: Drug
Name: laboratory biomarker analysis Type: Other
Name: pharmacological study Type: Other
Overall Status
RATIONALE: Estrogen can promote growth of endocrine sensitive breast cancer cells. Endocrine therapy with tamoxifen citrate may fight breast cancer by blocking the use of estrogen by the tumor cells. Pharmacokinetics and -genomics can have an impact on the efficacy of the treatment.

PURPOSE: This phase III trial is studying blood samples to see if the level of active metabolites of tamoxifen can be improved in patients with breast cancer.
Detailed Description


- To determine how the increase of tamoxifen citrate dose influences the level of its major metabolites in patients with hormone-sensitive breast cancer.


- To characterize the population pharmacokinetic profile

- To investigate the role of the other CYPs

- To assess the relation between clinical symptoms and CYP2D6 genotypes and/or active metabolites levels

- To explore the correlation between genotypes/metabolites levels and clinical outcomes in terms of tumor relapse.

- To assess the feasibility, efficacy, and safety of concentration-guided adjustment of tamoxifen citrate dosage.

- To conduct other exploratory analysis based on the eventual new data coming up in the future.

OUTLINE: Patients receive oral tamoxifen citrate (at a dose of 40 mg/day) daily for 4 months in the absence of disease progression or unacceptable toxicity.

Blood samples are collected for PK, genotyping, phenotyping, and further analysis.
Criteria for eligibility
Healthy Volunteers: No
Maximum Age: N/A
Minimum Age: 18 Years
Gender: Both

- Diagnosis of breast cancer

- Hormone-sensitive breast cancer defined as > 10% estrogen receptor and/or > 10% progesterone receptor positivity by immunohistochemistry

- Receiving treatment with tamoxifen citrate and must be eligible for exposure to higher doses


- No history of deep venous thrombosis or pulmonary embolism

- No history of endometrial carcinoma

- No known history of vaginal bleeding, endometriosis, endometrial hyperplasia, endometrial hypertrophy, and/or polyps

- Not pregnant or nursing

- No contraindication to tamoxifen citrate treatment

- No known allergy to midazolam or dextromethorphan


- See Disease Characteristics
Hôpitaux Universitaire de Genève
Genève, Switzerland
Status: Recruiting
Contact: Alexandre Bodmer, MD - 41 22 382 40 14
Centre Hospitalier Universitaire Vaudois
Lausanne, Switzerland
Status: Recruiting
Contact: Khalil Zaman, MD - 41-21-314-0168 - Khalil.Zaman@chuv.ch
Start Date
June 2009
Completion Date
December 2013
Centre Hospitalier Universitaire Vaudois
Centre Hospitalier Universitaire Vaudois
Record processing date
ClinicalTrials.gov processed this data on July 28, 2015
ClinicalTrials.gov page