The primary purpose of the study is to demonstrate that dapoxetine can prolong intravaginal ejaculatory latency time (IELT) compared with placebo in men with premature ejaculation (PE).

One form of male sexual dysfunction is premature ejaculation (PE), which is also referred to as rapid ejaculation (RE). The study consists of 2 phases: pre-randomization phase (a screening visit and a 2-week baseline period); 12-week double-blind treatment phase during which patients will receive one of 2 doses of dapoxetine or placebo for use on an "as-needed" basis. The total duration of the study is approximately 14 weeks. Assessments of effectiveness include the average intravaginal ejaculatory latency time (as measured by stopwatch) during sexual intercourse, during the treatment period; control over ejaculation, participant and partner satisfaction with sexual intercourse, participant overall impression of change and severity of symptoms, based on questions asked at monthly intervals through the treatment phase. Safety assessments include the incidence, severity, and type of adverse events during the study, ECGs, as well as laboratory tests. At the end of the baseline period, patients from selected study centers will undergo blood sampling and ECG monitoring before and after the first dose of study medication. The study hypothesis is that treatment for 12 weeks with dapoxetine prolongs intravaginal ejaculatory latency time, compared with placebo, in men with PE. Oral tablets of dapoxetine (30 milligrams [mg] or 60mg) or placebo taken as needed during 12 weeks of treatment. No more than 1 dose within a 24-hour period.

Inclusion Criteria:

• Patient is in a stable, monogamous sexual relationship with the same woman for at least 6 months and plans to maintain this relationship for the duration of the study
• history of premature ejaculation in the 6 months before study initiation not due to distress, interpersonal difficulty or medication withdrawal
• history of intravaginal ejaculatory latency time (IELT) of < = 2 minutes in at least 3 out of 4 events
• blood pressure < = 180/100 mmHg at screening and end of baseline
• patient and partner must agree to attempt sexual intercourse at minimum intervals specified in the protocol
• patient's partner must have a negative urine pregnancy test at time of screening

Exclusion Criteria:

• Not taken dapoxetine in a previous investigational drug study
• not using other forms of therapy for treatment of PE (behavioral therapy or medications applied to the skin)
• no history of any medical events that are associated with the development of PE
• not taken another investigational drug within 1 month
• no history of seizures or major psychiatric disorder such as depression or schizophrenia
• no alcohol abuse and dependence
• no known allergy or hypersensitivity to dapoxetine or other selective serotonin reuptake inhibitors (SSRIs)
• no partners with decreased interest in or painful intercourse or other forms of sexual dysfunction