Study to Investigate Effect of a New Drug (PF-00446687) in Males Suffering From Erectile Dysfunction

Study Overview
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Brief Summary
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The purpose of this study is to investigate the effect of up to 200 mg of PF-00446687 on erectile activity in males suffering from erectile dysfunction as well as examining the safety and toleration of the drug.

Official Title
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A 2-Cohort, Multi-Centre, Randomised, Double Blind, Placebo Controlled 4-Way Crossover Study To Assess The Efficacy Of Single Oral Doses Of PF-00446687 On Erectile Function In Men Suffering From Erectile Dysfunction, Using 100 Mg Sildenafil As A Positive Control.

Conditions
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Erectile Dysfunction

Intervention / Treatment
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* Drug: PF-00446687
* Drug: Placebo
* Drug: Placebo
* Drug: Sildenafil
* Drug: PF-00446687
* Drug: PF-00446687
* Drug: PF-00446687
* Drug: Placebo
* Drug: Placebo
* Drug: Sildenafil


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Males aged 18-65 years who has given written informed consent to participate in the study and who suffers moderate to severe erectile dysfunction who has a current or recent successful response to treatment with phosphodiesterase type 5 inhibitors Exclusion Criteria: Males with a history of significant cardiac disease; unstable angina or recent myocardial infarction. Males suffering from treated or untreated hypo- or hypertension Males currently receiving vasoactive medication Males taking medications contraindicated, or cautioned with sildenafil or MC4 agonists

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 65 Years

Sexes Eligible for Study
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Male

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Treatment
Allocation: Randomized
Intervention Model: Crossover Assignment
Masking: Double


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Placebo Comparator: Cohort 1; Study Period 1, 2, 3 or 4<br>Cohort 1: Exploring two single doses of PF-00446687 200 mg as well as sildenafil 100mg and placebo (double dummy design) | Drug: PF-00446687<br>* Single 200mg dose as an oral solution<br>Drug: Placebo<br>* Placebo for oral solution<br>Drug: Placebo<br>* Placebo for tablet<br>Drug: Sildenafil<br>* Single oral dose 100 mg tablet<br>|
| Placebo Comparator: Cohort 2; study periods 1, 2, 3 or 4<br>Cohort 2: Exploring single doses of PF-00446687 20 mg - 175 mg. Subjects to receive two of 3 possible doses of PF-00446687 as well as a single dose of sildenafil 100mg and placebo (double dummy design). | Drug: PF-00446687<br>* Single 125 mg dose as an oral solution<br>Drug: PF-00446687<br>* Single 175 mg dose as an oral solution<br>Drug: PF-00446687<br>* Single 20 mg dose as an oral solution<br>Drug: Placebo<br>* Placebo for oral solution<br>Drug: Placebo<br>* Placebo for tablet<br>Drug: Sildenafil<br>* Single oral dose 100 mg tablet<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Assess effect of single doses of PF-00446687 on erectile function (using the Rigiscan+ device) |  | Day of dosing | 
| Evaluate subjective self-assessment of sexual interest and desire by means of a questionnaire |  | Day of dosing | 
| Diary of sexual activities |  | From day of dosing to 7 days post-dose | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| PK assessment of PF-00446687 ad sildenafil |  | Day of dosing | 
| Safety and toleration |  | Day of dosing to follow-up | 
| Assess variability of response and repeatability of design between 2 similar doses |  | Comparison of response to be assessed until 7 days post-dose | 
| Assess agouti related protein levels in this population |  | Day of dosing |