Study on the possible pharmacokinetic interaction between grean tea supplements and tamoxifen in patients with breast cancer. the TEA study

Phase 2

Completed

Conditions: 10006291
Hormone sensitive breast cancer

Registration Number: NL-OMON48342

Lead Sponsor: Erasmus MC, Universitair Medisch Centrum Rotterdam

Brief Summary: Not available

Detailed Description: Not available

Recruitment & Eligibility

Status: Completed

Sex: Not specified

Target Recruitment: 14

Inclusion Criteria

1. Age * 18 years
2. Patients with a confirmed diagnosis of primary or advanced breast cancer,
who are on tamoxifen treatment for at least three months (steady state
concentration).
3. WHO performance * 1
4. Able and willing to sign the informed consent form prior to screening
evaluations
5. Willing to abstain from strong CYP3A4, CYP2D6, CYP2C9/2C19, UGT and P-gp
inhibitors or inducers, herbal or dietary supplements or other over-the-counter
medication besides paracetamol.
6. Willing to abstain from a cup of green tea (<4 h after tamoxifen intake)

Exclusion Criteria

1. Patients with known impaired drug absorption (e.g. gastrectomy and
achlorhydria)
2. Patients with an active gastric ulcer
3. Known serious illness or medical unstable conditions that could interfere
with this study requiring treatment (e.g. HIV, hepatitis, Varicella zoster or
herpes zoster, organ transplants, kidney failure (GFR<30 ml/min/1.73 m2),
serious liver disease (e.g. severe cirrhosis), cardiac and respiratory diseases)
4. A CYP2D6 poor metabolizer or ultra-rapid metabolizer phenotype based on
CYP2D6 genotyping outcome

Study & Design

Study Type: Interventional

Study Design: Not specified

Primary Outcome Measures

Name	Time	Method
<p>To compare the Area under the curve (AUC) of endoxifen in patients with breast<br /><br>cancer treated with tamoxifen with and without green tea.</p><br>

Secondary Outcome Measures

Name	Time	Method
<p>1. To compare the Area Under the Curve (AUC) of tamoxifen in patients with<br /><br>breast cancer treated with tamoxifen with and without green tea capsules.<br /><br>2. To compare other tamoxifen and endoxifen pharmacokinetic outcomes (i.e.<br /><br>clearance, maximum concentration (Cmax), minimal concentration (Ctrough) and<br /><br>time until maximum concentration (Tmax) and elimination half-life (T*)). in<br /><br>patients with breast cancer treated with tamoxifen with and without green tea.<br /><br>3. To evaluate the incidence and severity of side-effects of treatment with<br /><br>tamoxifen in absence and presence of green tea. </p><br>