Priligy: first licensed treatment for premature ejaculation

Priligy is approved for use in men who have experienced premature ejaculation (defined as ejaculation with minimal sexual stimulation and an intravaginal ejaculatory latency time [IELT] less than 2 minutes) in the majority of intercourse attempts over the preceding six months, with marked personal distress or interpersonal difficulty as a result.

PHARMACOLOGY

Dapoxetine is a short-acting selective serotonin reuptake inhibitor (SSRI). SSRIs are sometimes used off-label to treat premature ejaculation on the basis of their side-effect of delayed ejaculation. They act by inhibiting reuptake of serotonin into the presynaptic neuron, thereby potentiating the activity of the neurotransmitter. Unlike existing SSRIs, dapoxetine has a rapid onset of action, which makes it suitable for on-demand treatment.^1,2

CLINICAL STUDIES

Five double-blind placebo-controlled trials in a total of 6,081 men established the safety and efficacy of dapoxetine for premature ejaculation.^1–4

One study investigated the long-term effects of dapoxetine in patients across 22 countries. Participants were required to be in a stable monogamous relationship. Of the 1,162 men randomised, 618 completed treatment with dapoxetine 30mg or 60mg or placebo for 24 weeks, taken as needed. The primary end point was stopwatch measured IELT.³

Increased IELT

Mean average IELT increased from 0.9 minutes at baseline to 3.2 minutes and 3.5 minutes with dapoxetine 30mg and 60mg, respectively, at study endpoint, compared with 1.9 minutes with placebo (p<0.001 for both dapoxetine doses vs placebo); geometric mean IELT increased from 0.7 minutes at baseline to 1.8 minutes, 2.3 minutes and 1.1 minutes, respectively (p<0.001 for dapoxetine vs placebo) . All measures on the patient-reported Premature Ejaculation Profile (including perceived control over ejaculation, satisfaction with sexual intercourse, and personal distress and interpersonal difficulty related to ejaculation) improved to a significantly greater extent from baseline to weeks 12 and 24 with dapoxetine than with placebo (p<0.05 for both).³

The results of the other studies and pooled analysis of the data at week 12 were consistent.¹

Safety profile

Adverse events, most commonly nausea, dizziness, diarrhoea and headache, led to discontinuation in 3.9% of patients taking dapoxetine 30mg, 8.2% of patients taking dapoxetine 60mg and 1.3% of those receiving placebo.³ 

Personal distress

A trial conducted in the US and Canada assessed the treatment benefit of dapoxetine in terms of personal distress and interpersonal difficulty. A total of 652 patients completed treatment with dapoxetine 60mg taken as needed for 63 days.⁴

Among patients taking dapoxetine, the percentage of those reporting 'not at all' or ‘a little bit of’ personal distress related to ejaculation increased from 5% at baseline to 54.3% at study end (vs 35.3% of those given placebo; p<0.001). Similarly, the proportion of men reporting 'not at all' or ‘a little bit’ of interpersonal difficulty related to ejaculation increased from 40.9% in the dapoxetine group and 43.0% in the placebo group at baseline, to 76.8% and 64.2%, respectively (p<0.001).⁴

Over one third of patients (39.7%) receiving dapoxetine perceived their control over ejaculation to be ‘good’ or ‘very good’ at study end, compared with almost none (0.2%) at baseline (placebo, 20.4% vs 0%). Sexual satisfaction was rated as ‘good’ or ‘very good’ in the dapoxetine group by 54.7% of patients at study end, compared with 7.9% at baseline (placebo, 34.0% vs 9.5%).⁴

References:

1. Priligy Summary of Product Characteristics, February 2013.
2. Pryor J et al. Lancet 2006; 368: 929–37.
3. Buvat J et al. Eur Urol 2009; 55: 957–67.
4. Kaufman J et al. BJU Int 2008; 103: 651–8.

View Priligy drug record

Further information: Menarini

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