A Randomized, Double-Blinded, Placebo-Controlled, Two-Way Crossover Study to Investigate the Safety and Toleration of Single Dose Sildenafil in Subjects Receiving Chronic UK-369,0031

Study Overview
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Brief Summary
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To investigate the safety and overall tolerability of co-administration two PDE5 inhibitors UK369,003 and sildenafil

Official Title
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A Randomized, Double-Blinded, Placebo-Controlled, Two-Way Crossover Study to Investigate The Safety And Toleration Of Single Dose Sildenafil In Subjects Receiving Chronic UK-369,003.

Conditions
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Prostatic Hyperplasia, Urinary Bladder, Overactive, Erectile Dysfunction

Intervention / Treatment
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* Drug: UK369,003
* Drug: sildenafil
* Drug: sildenafil matching placebo


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Evidence of a personally signed and dated informed consent document indicating that the subject (or a legally acceptable representative) has been informed of all pertinent aspects of the study. Healthy male subjects between the ages of 40 and 55 years, inclusive Body Mass Index (BMI) of approximately 18 to 30 kg/m2; and a total body weight >50 kg (110 lbs). Exclusion Criteria: Evidence or history of clinically significant haematological, renal, endocrine, pulmonary, gastrointestinal, cardiovascular, hepatic, psychiatric, neurologic, or allergic disease (including drug allergies, but excluding untreated, asymptomatic, seasonal allergies at time of dosing). Loss of vision in one eye due to non-arteritic ischemic optic neuropathy (NAION) regardless of whether or not this event was temporally associated with the use of a PDE5 inhibitor.

Ages Eligible for Study
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Minimum Age: 40 Years
Maximum Age: 55 Years

Sexes Eligible for Study
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Male

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Basic Science
Allocation: Randomized
Intervention Model: Crossover Assignment
Masking: Double


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: UK369,003 + Placebo or sildenafil<br>All subjects will receive 17 days daily dosing of UK-369,003 100 mg MR Subjects will receive single oral doses of the following interactant treatments in a randomized order On Day 14, a single dose of sildenafil-matching placebo or 100 mg sildenafil and on Day 17 a single dose of 100 mg sildenafil or a sildenafil matching placebo | Drug: UK369,003<br>* oral tablet, once a day<br>Drug: sildenafil<br>* single oral dose on day 14 or day 17<br>* Other names: viagra;Drug: sildenafil matching placebo<br>* single oral dose on day 14 or day 17<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Safety and toleration assessed by non-leading questioning, incidence of adverse events and laboratory testing. |  | hours | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Incidence of postural hypotension. |  | hours | 
| Standing and supine pulse rate (PR) at each postdose time. |  | hours | 
| Standing systolic and diastolic blood pressure (BP) and supine systolic and diastolic BP at each postdose time. |  | hours |