Proof of Mechanism in ELT

Inclusion criteria

• Heterosexual male subject with self-reported moderate or severe primary Premature ejaculation with ejaculation occurring on or before penetration, or shortly there after with minimal stimulation
• Baseline Ejaculation Latency time < 3 minutes
• Subjects must agree to use a contraception methods as per protocol
• Body weight > or = 50 kg and Body Mass Index within the range 19.0-29.9 Kg/m2
• Subject with normal visual acuity (with appropriate correction if needed)
• Subject able to cooperate in all study procedure including the eye examination with use of mydriatics

Exclusion criteria

• Erectile dysfunction
• History of migraine
• Current clinically relevant abnormality
• History of psychiatric illness or suicidal attempts or behaviours
• History of any eye disorder or colour blind, excluding myopia and presbyopia
• Cardiac conduction disorder or other clinically significant cardiac disease
• Positive at pre-study drug/alcohol screen and to Hepatitis or HIV tests
• Regular consumption of alcohol
• History of sensitivity or intolerance to drugs
• Consumption of red wine, seville oranges, grapefruit or grapefruit juice [and/or pummelos, exotic citrus fruits, grapefruit hybrids] from 7 days prior to the first dose of study medication
• Subject has received or is continuing to receive any treatment for premature ejaculation in the four weeks prior to the study start
• Use of prescription or non-prescription drugs, including vitamins, herbal and dietary supplements prior to the first dose of study medication
• Participation in another clinical trial in the previous month
• Exposure to more than four new experimental drugs within the previous 12 months
• Where participation in the study would result in donation of blood or blood products in excess of 500 mL within a 56 day period.
• Unwillingness or inability to follow the procedures outlined in the protocol.