Study to Investigate the Effect of Paroxetine Mediated CYP2D6 Inhibition on the Pharmacokinetics of Tamsulosin in Healthy Male Volunteers

Study Overview
=================
Brief Summary
-----------------
Study to investigate the effect of CYP2D6 inhibition by paroxetine on the single oral dose pharmacokinetics of tamsulosin and to investigate the effect on safety and tolerability

Official Title
-----------------
An Open Label Randomized Two-way Crossover Study to Investigate the Effect of Paroxetine Mediated CYP2D6 Inhibition on the Single Oral Dose Pharmacokinetics of Tamsulosin in Healthy Male Volunteers (CYP2D6 Extensive Metabolizers)

Conditions
-----------------
Healthy

Intervention / Treatment
-----------------
* Drug: Tamsulosin
* Drug: Paroxetine


Participation Criteria
=================
Eligibility Criteria
-----------------
Inclusion Criteria: All participants in the study are Healthy males Ranging from 21 to 50 years of age Body mass index (BMI) within 18.5 to 29.9 kg/m2 In accordance with Good Clinical Practice (GCP) and the local legislation all volunteers will have given their written informed consent prior to admission to the study Exclusion Criteria: Any finding of the medical examination (including blood pressure, pulse rate and ECG) deviating from normal and of clinical relevance Gastrointestinal, hepatic, renal, respiratory, cardiovascular, metabolic, immunological or hormonal disorders, clinically relevant electrolyte disturbances Diseases of the central nervous system (such as epilepsy) or psychiatric disorders or neurological disorders History of orthostatic hypotension, fainting spells or blackouts Chronic or clinically relevant acute infections History of allergy/hypersensitivity (including drug allergy) which is deemed relevant to the trial as judged by the investigator Intake of drugs with a long half-life (> 24:00 hours) within at least one month or less than ten half-lives of the respective drug before enrolment in the study or during the study Use of any drugs which might influence the results of the trial up to 7 days prior to enrolment in the study or during the study Participation in another trial with an investigational drug (within two months prior to administration or during the trial) Smoker (> 10 cigarettes or > 3 cigars of > 3 pipes/day) Inability to refrain from smoking on trial days Alcohol abuse (> 60 g/day) Drug abuse Blood donation (> 100 mL within four weeks prior to administration or during the trial) Any laboratory value outside the reference range if indicative of underlying disease or poor health Excessive physical activities within the last week before the trial or during the trial Hypersensitivity to treatment medication and/or related drugs of these classes Non extensive metabolizer (EM) for CYP2D6

Ages Eligible for Study
-----------------
Minimum Age: 21 Years
Maximum Age: 50 Years

Sexes Eligible for Study
-----------------
Male

Accepts Healthy Volunteers
-----------------
Accepts Healthy Volunteers

Study Plan
=================
How is the study designed?
-----------------

Design Details

Primary Purpose: Treatment
Allocation: Randomized
Intervention Model: Crossover Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Tamsulosin + Paroxetine<br>Tamsulosin: q.d on day 1 Paroxetine: higher dose q.d. on days -7 to 2 q.d., lower dose on days -10 to -8 and 3 to 5 | Drug: Tamsulosin<br> <br> * Other names: Alna®;Drug: Paroxetine<br> <br> * Other names: Tagonis®;|
| Active Comparator: Tamsulosin<br>Tamsulosin: q.d on day 1 | Drug: Tamsulosin<br> <br> * Other names: Alna®;|

What is the study measuring?
-----------------
Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Cmax (maximum measured concentration of tamsulosin HCl in plasma) |  | up to 48 hours after dosing | 
| AUC0-∞ (area under the concentration-time curve of tamsulosin HCl in plasma over the time interval from 0 extrapolated to infinity) |  | up to 48 hours after dosing | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| tmax (time from dosing to the maximum measured concentration of tamsulosin HCl in plasma) |  | up to 48 hours after dosing | 
| AUC0-tz (area under the concentration-time curve of tamsulosin HCl in plasma over the time interval from 0 to the last quantifiable data point) |  | up to 48 hours after dosing | 
| λz (terminal rate constant of tamsulosin HCl in plasma) |  | up to 48 hours after dosing | 
| t1/2 (terminal half-life of tamsulosin HCl in plasma) |  | up to 48 hours after dosing | 
| MRTpo (mean residence time of tamsulosin HCl in the body after oral administration) |  | up to 48 hours after dosing | 
| CL/F (apparent clearance of tamsulosin HCl in plasma after an extravascular administration) |  | up to 48 hours after dosing | 
| Vz/F (apparent volume of distribution of tamsulosin HCl during the terminal phase λz following an extravascular administration) |  | up to 48 hours after dosing | 
| RCmax,T/R (ratio of the Cmax value of the test treatment to the Cmax value of the reference treatment after single dose) |  | up to 48 hours after dosing | 
| RAUC0-∞,T/R (ratio of the test treatment versus the reference treatment from zero to infinity, expressed as ratio of AUC values after single dose) |  | up to 48 hours after dosing | 
| Number of subjects with adverse events |  | up to 21 days after last treatment | 
| Assessment of tolerability by investigator on a 4-point scale |  | within 21 days after last treatment |