A Multicenter, Randomized, Parallel Group, Double-Blind, Placebo Controlled, Flexible Dose Escalation Study To Evaluate Sexual And Relationship Satisfaction In The Female Partner Of Men With Erectile Dysfunction Treated With Sildenafil Citrate

• International Index of Erectile Function (IIEF) Erectile Function, Desire, Orgasm, Intercourse Satisfaction, and Overall Satisfaction Domains in ED patients [ Time Frame: Week 8 and Week 12 ] [ Designated as safety issue: No ]
• Self-Esteem and Relationship Questionnaire (SEAR) in ED patients [ Time Frame: Week 12 ] [ Designated as safety issue: No ]
• ED Subject Event Log in ED patients [ Time Frame: Week 12 ] [ Designated as safety issue: No ]
• Erectile Dysfunction Inventory of Treatment Satisfaction (EDITS) index of treatment satisfaction in ED patients [ Time Frame: Week 12 ] [ Designated as safety issue: No ]
• Dyadic Adjustment Scale (DAS) in ED patients [ Time Frame: Week 8 and Week 12 ] [ Designated as safety issue: No ]
• American Urological Association (AUA) Symptom Index in ED patients [ Time Frame: Week 12 ] [ Designated as safety issue: No ]
• Global Efficacy Assessment Questions (GEQ) in ED patients [ Time Frame: Week 12 ] [ Designated as safety issue: No ]
• Questions 1 and 2 of Female Partner of ED Subject Questionnaire (FePEDS-Q) in female partners [ Time Frame: Week 8 and Week 12 ] [ Designated as safety issue: No ]
• Sexual Function Questionnaire (SFQ) Desire, Arousal, Enjoyment and Orgasm Domains in female partners [ Time Frame: Week 12 ] [ Designated as safety issue: No ]
• Female Sexual Function Inventory (FSFI) Desire, Satisfaction and Arousal Domains in female partners [ Time Frame: Week 12 ] [ Designated as safety issue: No ]
• Partner EDITS in female partners [ Time Frame: Week 12 ] [ Designated as safety issue: No ]
• Female Partner Treatment Continuation Question in female partners [ Time Frame: Week 12 ] [ Designated as safety issue: No ]
• Dyadic Adjustment Scale (DAS) in female partners [ Time Frame: Week 8 and Week 12 ] [ Designated as safety issue: No ]
• Beck Depression Inventory (BDI-II) in female partners [ Time Frame: Week 12 ] [ Designated as safety issue: No ]
• Female Partner Event Log in female partners [ Time Frame: Week 12 ] [ Designated as safety issue: No ]
• AUA Symptom Index in female partners [ Time Frame: Week 12 ] [ Designated as safety issue: No ]

To compare the effects of sildenafil versus placebo on the female partner's sexual satisfaction as assessed by Question 3 of Female Partner of Erectile Dysfunction (ED) Subject Questionnaire (FePEDS-Q): "Over the past 4 weeks, when you had sexual intercourse, how often was it satisfactory for you?" For ED subjects, determine difference in the Erectile Function domain of International Index of Erectile Function (IIEF) between sildenafil citrate and placebo at end of the treatment phase and determine the overall relationship between improved erectile function and increased ED subject and female partner satisfaction.

• Drug: sildenafil
  sildenafil 50 mg (initial dose) tablet by mouth 30 to 60 minutes prior to sexual activity for 12 weeks; depending upon safety, efficacy and tolerability, the dose could be increased to 100 mg or reduced to 25 mg, if necessary.
• Drug: placebo
  placebo tablet by mouth 30 to 60 minutes prior to sexual activity for 12 weeks

• Active Comparator: Arm 1
  Intervention: Drug: sildenafil
• Placebo Comparator: Arm 2
  Intervention: Drug: placebo

Inclusion Criteria:

• The male patient must have had a documented clinical diagnosis of erectile dysfunction (ED) confirmed by a Sexual Health Inventory-Male (SHI-M) score of less than or equal to 21
• a stable female partner at least 21 years of age for at least 6 months prior to screening
• the couple must have been married or living together at the time of screening.
• The female partner must have answered "no intercourse," "sometimes," "a few times" or "almost never" on Question 3 of the Female Partner of ED Subject Questionnaire (FePEDS-Q)

Exclusion Criteria:

• The male patient must not have had resting sitting and/or standing hypotension (BP < 90/50mmHg) or hypertension (BP > 170/110mmHg), or significant cardiovascular disease in the last 3 months, including cardiac failure, myocardial infarction, unstable angina, stroke, transient ischemic attack (TIA), symptomatic or clinically significant cardiac arrhythmias.
• Female partners must not have had significant dyspareunia or lifelong significant sexual dysfunction based on female partner's medical and sexual history at screening.