Hormone sensitieve breast cancer
Conditions
Interventions
Tamoxifen will be used as standard care of treatment (adjuvant and metastatic
setting). Tamoxifen is given in a dosage of 20-40 mg q.d. Dose modifications
are not allowed after the run-in phase of t
Sponsors
Erasmus MC, Universitair Medisch Centrum Rotterdam
Eligibility
Age
18 Years to 99 Years
Inclusion criteria
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 (see Appendix B) 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. Adequate organ function defined as: - ALAT and ASAT 30 ml/min/1.73 m2 - Controlled thyroid dysfunction
Exclusion criteria
Exclusion criteria: 1. Pregnant or lactating patients 2. Patients with known impaired drug absorption (e.g. gastrectomy and achlorhydria) 3. Patients with a history of (stomach) ulcers or gastric bleeding or hypersensitivity to NSAIDs. 4. 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
Design outcomes
Primary
| Measure | Time frame |
|---|---|
| To investigate the interaction between diclofenac and tamoxifen; by comparing the Area under the curve (AUC) of endoxifen in patients with breast cancer treated with tamoxifen with and without diclofenac. | — |
Secondary
| Measure | Time frame |
|---|---|
| 1. To compare the Area Under the Curve (AUC) of tamoxifen and endoxifen-glucuronide in patients with breast cancer treated with tamoxifen with and without diclofenac. 2. To compare other tamoxifen, endoxifen-glucuronide and endoxifen pharmacokinetic outcomes (i.e. clearance, maximum concentration (Cmax), minimal concentration (Ctrough) and time until maximum concentration (Tmax) and elimination half-life (T*)). Furthermore the endoxifen/endoxifen-glucuronide ratio in patients with breast cancer treated with tamoxifen with and without diclofenac. 3. To evaluate the incidence and severity of side-effects of treatment with tamoxifen in absence and presence of diclofenac. | — |
Countries
Netherlands
Outcome results
None listed