Clinical trial · Interventional
Testosterone & Tamoxifen Trial
T&T Trial: Adding Testosterone to Tamoxifen in Male Breast Cancer Patients
NCT05156606CI-TRIAL-00079602T&TterminatedN/AClinicalTrials.gov clinicaltrialsProvenance
- Source
- ClinicalTrials.gov
- Retrieved
- Sep 8, 2026
- Layer
- normalized (units and labels harmonized; values unchanged)
- Run
- ING-CLINICALTRIALS-20260908-000001
Why stopped (as posted): Five patients were included; it did not succeed in recruiting the target number of 6 patients. This is as a result of the rarity of this disease in men.
Summary
Brief summary (as posted)
This is a concise single arm, feasibility study, which will be executed in the University Medical Center Groningen, The Netherlands. Male patients with metastatic BC (n=6) are eligible for this study after at least 1 line of conventional endocrine therapy.
Conditions
Conditions (1)
Free-text conditions as registered, with the CancerIndex entity they were reconciled to and the match type.
| Condition (as posted) | Mapped entity | Match | Confidence |
|---|---|---|---|
| Male Breast Cancer | Male Breast Carcinoma | ALIAS | 0.90 |
Interventions
Interventions (1)
| Intervention | Type | Mapped drug | Match |
|---|---|---|---|
| AndroGel | Drug | — | UNRESOLVED |
Design
Arms and outcomes
Arms (1)
- type
- EXPERIMENTAL
- label
- treatment
- description
- After the baseline imaging with FES- and FDHT-PET is completed, tamoxifen 20mg 1dd1 (standard dosage) plus testosterone (Androgel®) will be started. The first 3 patients will receive 25mg testosterone once daily (half the standard starting dosage for male hypogonadism). If this is well tolerated after 3 weeks, the dosage will be increased to 50mg once daily. Out of precaution, the safety profile of the 50mg dosage in the first 3 patients will be evaluated after all 3 patients have received 50mg testosterone for 2 cycli (8 weeks), prior to proceeding to the next 3 patients. Patients will be treated with tamoxifen and testosterone until disease progression or unacceptable toxicity.
- interventionNames
- Drug: AndroGel
Primary outcomes (1)
- measure
- Safety profile
- timeFrame
- At 8 weeks and follow-up through study completion, an average of 1 year
- description
- Safety profile, defined as the number of AEs and SAEs that occur while on tamoxifen and testosterone treatment.
Secondary outcomes (4)
Eligibility
Eligibility (as posted)
- Sex
- Male
- Minimum age
- 18 Years
Show eligibility criteria text
Inclusion Criteria: 1. Male 2. A history of proven ER+ (\>10% of cells), AR+ (\>10% of cells), and HER2- metastatic BC 3. Tumor progression after at least one line of conventional endocrine therapy (tamoxifen, AI, fulvestrant, CDK4/6, ±LHRH analogue). 4. Age ≥ 18 years 5. Adequate hematological, renal and liver function as follows: * Absolute neutrophil count \> 1.5 x 109/L * Platelet count \>100 x 109/L * White blood cell count \>3 x 109/L * AST and ALT \<2.5 or \<5.0 in case of liver metastases x upper limit of normal (ULN) * Creatinine clearance \>50mL/min * Prothrombin time, partial thromboplastin time and INR \<1.5 x ULN 6. Written informed consent Exclusion Criteria: 1. History of prostate, testicular or liver cancer 2. Patients already using testosterone supplements 3. Patients using medication with anti-androgenic effects (e.g. spironolactone) 4. Elevated PSA (\>4μg/L) or severe urinary tract problems (as defined with a Prostate Symptom Score \>19). Patients with known BRCA mutation and PSA \>3 μg/L will be referred to the urologist for prostate cancer screening, and can participate if they have no signs of prostate cancer. 5. Hematocrit \>50% 6. Patients with uncontrolled hypertension, diabetes mellitus or other significant cardiovascular morbidity. 7. Patients with recent history of coronary artery disease or trombo-embolic events within 6 months prior to screening 8. Severe concurrent disease, infection, co morbid condition that, in the judgment of the investigator would make the patient inappropriate for enrollment 9. Visceral crisis and/or rapid progression necessitating chemotherapy 10. Previous allergic reaction to androgen agonists 11. Contra-indication for PET imaging 12. Tamoxifen or fulvestrant treatment \<5 weeks prior to FES-PET.
References
Publications (0)
Data not yet available
No reference posted for this study.