Comparison of paroxetine and dapoxetine, a novel selective serotonin reuptake inhibitor in the treatment of premature ejaculation

An update on the treatment of premature ejaculation: A systematic review

To analyse the current therapeutic options for patients with premature ejaculation (PE) and highlight their mechanism(s) of action, effectiveness, advantages and limitations. A literature search was conducted using the PubMed database searching for articles exploring different PE treatment modalities. A Preferred Reporting Items for Systemic Reviews and Meta-Analyses (PRISMA) approach was used to report the results of the literature search. A total of 149 articles were included in this review. The currently available treatment methods for PE include behavioural therapy, local anaesthetics, tricyclic antidepressants, selective serotonin reuptake inhibitors, and selective phosphodiesterase inhibitors. Most PE treatments are either experimental or used off-label. New treatments are certainly warranted to overcome this exasperating sexual dysfunction.

Abbreviations: AIPE: Arabic Index of Premature Ejaculation; CNS: central nervous system; CYP: cytochrome P450; ED: erectile dysfunction; FDA: United States Food and Drug Administration; H1: histamine receptors; 5-HT: 5-hydroxytryptamine; IELT: The intravaginal ejaculation latency time; IPE: Index of Premature Ejaculation; M1: muscarinic receptors; OCD: obsessive–compulsive disorder; PDE5: phosphodiesterase type 5; PE: premature ejaculation; PEP: Premature Ejaculation Profile; PRO: patient-reported outcome; RCT: randomised controlled trial; SS: Severance Secret (cream); SSRIs: selective serotonin reuptake inhibitors; TCAs: tricyclic antidepressants

Progresses in pharmaceutical and surgical management of premature ejaculation

OBJECTIVE

Premature ejaculation (PE) is regarded as one of the most common male sexual dysfunctions. This review introduced several pharmaceutical and surgical methods for the management of PE. The definition, etiology, behavioral, and psychological therapy of PE were also discussed.

DATA SOURCES

"Premature," "ejaculation," or "sexual dysfuction" were used as the medical subject headings (MeSH) to obtain relevant articles before June 2019 on Pubmed, Google Scholar and CNKI. Most articles used were written in English and several Chinese articles were also cited.

STUDY SELECTION

Full-text articles of retrospective/prospective/randomized controlled trials were analyzed. Animal experiments and letters were excluded.

RESULTS

There are four PE sub-types: lifelong PE, acquired PE, natural variable PE, and subjective PE. Behavioral therapy, psychotherapy, medication, topical anesthetics, and surgery are currently used for the treatment of PE. However, all the above treatments have limitations. Therefore, novel ways should be investigated to more efficiently control PE.

CONCLUSIONS

The pharmaceutical therapy that is currently being used in clinical practice for the management of PE is still the main choice globally due to its good efficacy. Surgery may be a choice for patients who are resistant to medication. However, it should be performed cautiously.

Comparison of the treatment efficacies of paroxetine, fluoxetine and dapoxetine in low socioeconomic status patients with lifelong premature ejaculation

Introduction

To assess the treatment efficacies of paroxetine, fluoxetine and dapoxetine in patients with lifelong premature ejaculation (PE).

Material and methods

One hundred and seventy male patients with lifelong PE were included in our study. Premature ejaculation profile (PEP) and Intravaginal ejaculation latency times (IELT) were recorded. Paroxetine 20 mg/d was given in Group 1 (n = 64), fluoxetine 20 mg/d was given in Group 2 (n = 47) and dapoxetine 30 mg on demand (at least two times/week) was given in Group 3 (n = 59) patients. After 1 month of treatment, the patients' IELT, PEP and patient reported clinical global impression of change (CGIC) were completed.

Results

The mean age was 36 ±9.2 years. There was no difference between the groups' age, PEP and IELT before treatment (p >0.05). PEP and IELT improved in all three groups (p <0.001). The changes in the 1^st and 3^rd questions of PEP was significantly higher in group 1 than in the other groups (pPEP-1 = 0.042, pPEP-3 = 0.001). The changes in the 2^nd and 4^th questions of PEP were similar between groups (pPEP-2 = 0.444, pPEP-4 = 0.442). In group 1 and 3 IELT changes were better than group 2 (pIIEL1-3 = 0.297, pIIEL1-2 = 0.017, pIIEL2-3 = 0.100). There was no difference between CGIC scores (p = 0.087). The treatment was terminated by 8 patients in Group 1 and 9 patients in Group 2 because of side effects.

Conclusions

While paroxetine treatment seemed to be better than the other medications, dapoxetine 30 mg treatment has less side effects than the two others and its' on demand usage makes it more prominent than the others.

Efficacy and Safety of "On-Demand" Dapoxetine in Treatment of Patients with Premature Ejaculation: A Meta-Analysis

Background

The aim of this study was to assess the efficacy and safety of “on-demand” dapoxetine in the treatment of premature ejaculation (PE).

Material/Methods

We performed a meta-analysis of intravaginal ejaculatory latency time (IELT), patient-reported global impression of change (PGIC), perceived control over ejaculation (PCOE), and drug-related adverse effects (AEs). We searched Medline, PubMed, Embase, CNKI, Wanfang, and VIP databases up to May 30, 2018 with the following search terms: “dapoxetine” or “SSRIs” and “premature ejaculation” or “sexual dysfunction”.

Results

Our analysis included 11 RCTs (8521 cases and 4338 controls). We found that IELT, PGIC, and PCOE in PE patients with “on-demand” dapoxetine were significantly higher than in the control group, and we observed higher proportions in 60 mg vs. 30 mg dapoxetine. The AEs were mild and tolerable.

Conclusions

“On-demand” dapoxetine is effective and safe for patients with PE, and a dose of 60 mg may be more effective than 30 mg.

Paroxetine in the treatment of premature ejaculation: a systematic review and meta-analysis

Background

Paroxetine is one of the selective serotonin reuptake inhibitors (SSRIs) used in the treatment of premature ejaculation (PE). However, this use is not approved in many countries. The purpose of this systematic review and meta-analysis is to review the efficacy and safety of paroxetine for PE patients.

Methods

We searched relevant randomized, controlled trials through May 2018, using PubMed, Embase and Cochrane Central Register. The main endpoint included intra-vaginal ejaculatory latency time (IELT) and side effects in the treatment of PE. Cochrane Collaboration’s Revman software, version 5.3, was used for statistical analysis.

Results

Out of 493 unique articles, a total of 19 randomized, controlled trials (RCTs) were reviewed. Quite a few RCTs were considered to have unclear risk of bias because of limited information. Pooled outcomes suggested that paroxetine was more effective than placebo, fluoxetine and escitalopram at increasing IELT (all p < 0.05). However, there existed a high level of heterogeneity in the paroxetine vs. fluoxetine groups and the paroxetine vs. placebo groups. Comparing paroxetine with tramadol, sertraline, phosphodiesterase 5 inhibitors (PDE5Is), local lidocaine gel, behaviour therapy or dapoxetine, we found that the increase in IELT was not statistically significant between groups. Paroxetine combined with tadalafil or behaviour therapy was more efficacious than paroxetine alone (all p < 0.05). Although the side effects in the combination group were more common than in the paroxetine alone group, the most common adverse events, such as nausea, muscle soreness, palpitation and flushing, were mild and tolerable. The main limitations of this systematic review and meta-analysis were the different definitions of PE and short follow-up times.

Conclusions

According to this systematic review and meta-analysis, paroxetine provided better efficacy than placebo, fluoxetine and escitalopram in the treatment of PE, with well-tolerated side effects. The combination group had better efficacy than the paroxetine alone group.

Trial registration

This review was reported in agreement with the PRISMA statement and was registered on PROSPERO 2018CRD42018097014.

Comparison of the clinical efficacy and safety of the on-demand use of paroxetine, dapoxetine, sildenafil and combined dapoxetine with sildenafil in treatment of patients with premature ejaculation: A randomised placebo-controlled clinical trial

The aim of the study was to compare the clinical efficacy and safety of the on-demand use of paroxetine, dapoxetine, sildenafil and combined dapoxetine with sildenafil in treatment of patients with premature ejaculation (PE). In a single-blind placebo-controlled clinical study, 150 PE patients without erectile dysfunction (ED) were included during the period of March 2015 to May 2016. Patients were randomly divided into five groups (30 patients each). On demand placebo, paroxetine (30 mg), dapoxetine (30 mg), sildenafil citrate (50 mg) and combined dapoxetine (30 mg) with sildenafil citrate (50 mg) were given for patients for 6 weeks in each group respectively. All patients were instructed to record intravaginal ejaculatory latency time (IELT) and evaluated with Premature Ejaculation Diagnostic Tool (PEDT) and the patient satisfaction score before and after treatment. The mean of IELT, satisfaction score and PEDT in all groups was significantly improved after treatment (p value = .001). Combined dapoxetine with sildenafil group had the best values of IELT, satisfaction scores and PEDT in comparison with other treatment groups (p value <.001). The combined dapoxetine with sildenafil therapy could significantly improve PE patients without ED as compared to paroxetine alone or dapoxetine alone or sildenafil alone with tolerated adverse effects.

Discontinuation of Dapoxetine Treatment in Patients With Premature Ejaculation: A 2-Year Prospective Observational Study

Introduction

Although dapoxetine is the only oral pharmacologic agent approved for the treatment of premature ejaculation (PE) and is very effective, the discontinuation rate is high.

Aim

To assess the discontinuation rate of patients with PE and the reasons for discontinuation in real-world practice.

Methods

In total, 182 consecutive patients were enrolled. Type of PE, self-estimated intravaginal ejaculation latency time, and medical history were evaluated in all patients who also completed the erectile function domain of the International Index of Erectile Function (IIEF). Visits were scheduled 1, 3, 6, 12, and 24 months after initiation of therapy; treatment status and the reasons for discontinuation in those who did discontinue were checked. The relations of discontinuation rates were compared with various parameters and the time to discontinuation after treatment commencement.

Results

Of all patients, 9.9% continued treatment to 2 years. The cumulative discontinuation rates at 1, 3, 6, 12, and 24 months were 26.4%, 61.6%, 79.1%, 87.3%, and 90.1%, respectively. Moreover, 79.1% of all patients discontinued treatment within 6 months. After 12 months, the discontinuation rate decreased sharply. The reasons for discontinuation were cost (29.9%), disappointment that PE was not curable and that dapoxetine was required every time sexual intercourse was contemplated (25%), side effects (11.6%), perceived poor efficacy (9.8%), a search for other treatment options (5.5%), and unknown (18.3%). Patients with acquired PE (vs lifelong PE), with intravaginal ejaculation latency time longer than 2 minutes before treatment, on phosphodiesterase type 5 inhibitors, and with IIEF erectile function scores lower than 26 tended to discontinue early and thus exhibited high dropout rates.

Conclusion

The treatment discontinuation rate of dapoxetine was very high. The main reasons for discontinuation were the cost and disappointment that treatment was required every time adequate sexual function was required.

Park HJ, Park NC, Kim TN, et al. Discontinuation of Dapoxetine Treatment in Patients With Premature Ejaculation: A 2-Year Prospective Observational Study. Sex Med 2017;5:e99–e105.

Emerging and investigational drugs for premature ejaculation

Over the past 20−30 years, the premature ejaculation (PE) treatment paradigm, previously limited to behavioural psychotherapy, has expanded to include drug treatment. Pharmacotherapy for PE predominantly targets the multiple neurotransmitters and receptors involved in the control of ejaculation which include serotonin, dopamine, oxytocin, norepinephrine, gamma amino-butyric acid (GABA) and nitric oxide (NO). The objective of this article is to review emerging PE interventions contemporary data on the treatment of PE was reviewed and critiqued using the principles of evidence-based medicine. Multiple well-controlled evidence-based studies have demonstrated the efficacy and safety of selective serotonin reuptake inhibitors (SSRIs) in delaying ejaculation, confirming their role as first-line agents for the medical treatment of lifelong and acquired PE. Daily dosing of SSRIs is likely to be associated with superior fold increases in IELT compared to on-demand SSRIs. On-demand SSRIs are less effective but may fulfill the treatment goals of many patients. Integrated pharmacotherapy and CBT may achieve superior treatment outcomes in some patients. PDE-5 inhibitors alone or in combination with SSRIs should be limited to men with acquired PE secondary to co-morbid ED. New on-demand rapid acting SSRIs, oxytocin receptor antagonists, or single agents that target multiple receptors may form the foundation of more effective future on-demand medication. Current evidence confirms the efficacy and safety of dapoxetine, off-label SSRI drugs, tramadol and topical anaesthetics drugs. Treatment with α1-adrenoceptor antagonists cannot be recommended until the results of large well-designed RCTs are published in major international peer-reviewed medical journals. As our understanding of the neurochemical control of ejaculation improves, new therapeutic targets and candidate molecules will be identified which may increase our pharmacotherapeutic armamentarium.

A Prospective Randomized Controlled Study to Compare Acupuncture and Dapoxetine for the Treatment of Premature Ejaculation

PURPOSE

To compare the safety and efficacy of dapoxetine and acupuncture for the treatment of premature ejaculation (PE) with other treatment methods.

METHODS

One hundred twenty patients with PE in an outpatient urology clinic were randomized to receive dapoxetine 30 mg and 60 mg, acupuncture or sham acupuncture. The intravaginal ejaculatory latency time (IELT), the PE diagnostic tool (PEDT) score, and adverse events were compared.

RESULTS

There were no differences between the groups in terms of age, body mass index, baseline IELT and PEDT scores (p > 0.05). After 4 weeks, IELT was significantly longer compared to baseline values in all groups (p < 0.001 for all comparisons). Comparisons between the groups showed that changes in IELT and PEDT observed after 4 weeks with dapoxetine 60 mg was significantly higher than those achieved in all other groups (p < 0.001 for all comparisons), changes observed with dapoxetine 30 mg was significantly higher than those achieved with acupuncture and sham acupuncture groups (p < 0.001 for both comparisons) and changes observed with acupuncture was significantly higher than those observed with sham acupuncture (p < 0.001).

CONCLUSION

Our results confirm previous reports on the efficacy and safety of dapoxetine. Although less effective than dapoxetine, acupuncture had a significant ejaculation-delaying effect.

Impact of Antidepressant Drugs on Sexual Function and Satisfaction

Pleasurable sexual activity is important in many human relationships and can provide a sense of physical, emotional and social well-being. Depressive symptoms and depressive illness are associated with impairments in sexual function and sexual dissatisfaction in untreated and treated patients. Most currently available antidepressant drugs are associated with development or worsening of sexual dysfunction in a substantial proportion of patients. Sexual difficulties during antidepressant treatment often resolve as depression lifts, but can persist over long periods, reducing self-esteem and affecting mood and relationships adversely. Sexual difficulties during antidepressant treatment typically have many possible causes but the incidence and nature of dysfunction varies between drugs. Many interventions can be considered when managing sexual dysfunction associated with antidepressants but no approach is 'ideal'. Because treatment-emergent sexual difficulties are less frequent with certain drugs, presumably related to differences in pharmacological properties, and since current interventions are suboptimal, a lower incidence of sexual dysfunction is a relevant tolerability target when developing novel antidepressants.

Current and Emerging Treatments for Premature Ejaculation

INTRODUCTION

Over the past 20-30 years, the premature ejaculation (PE) treatment paradigm, previously limited to behavioral psychotherapy, has expanded to include drug treatment. Pharmacotherapy for PE predominantly targets the multiple neurotransmitters and receptors involved in the control of ejaculation, which include serotonin, dopamine, oxytocin, norepinephrine, gamma amino-butyric acid (GABA) and nitric oxide (NO).

AIM

The objective of this article is to review current and emerging PE interventions.

METHODS

Contemporary data on the treatment of PE were reviewed and critiqued using the principles of evidence-based medicine.

MAIN OUTCOME MEASURE

Integrated pharmacotherapy and cognitive behavioral therapy (CBT) may achieve superior treatment outcomes in some patients. Phosphodiesterase type 5 inhibitors alone or in combination with selective serotonin reuptake inhibitors (SSRIs) should be limited to men with acquired PE secondary to comorbid erectile dysfunction (ED). New on-demand rapid-acting SSRIs, oxytocin receptor antagonists, or single agents that target multiple receptors may form the foundation of more effective future on-demand medication.

RESULTS

Multiple well-controlled evidence-based studies have demonstrated the efficacy and safety of SSRIs in delaying ejaculation, confirming their role as first-line agents for the medical treatment of lifelong and acquired PE. Daily dosing of SSRIs is likely to be associated with superior fold increases in intravaginal ejaculation latency time compared with on-demand SSRIs. On-demand SSRIs are less effective but may fulfill the treatment goals of many patients.

CONCLUSIONS

Current evidence suggests that psychosexual CBT has a limited role in the contemporary management of PE and confirms the efficacy and safety of dapoxetine, off-label SSRI drugs, and topical anesthetics drugs. Treatment with tramadol, α1-adrenoceptor antagonists cannot be recommended until the results of large, well-designed randomized controlled trials are published in major international peer-reviewed medical journals. As our understanding of the neurochemical control of ejaculation improves, new therapeutic targets and candidate molecules will be identified, which may increase our pharmacotherepeutic armamentarium. McMahon CG. Current and emerging treatments for premature ejaculation. Sex Med Rev 2015;3:183-202.

Association Between Changes in Serum 5-Hydroxy-Tryptamine Concentrations and Improvement in Clinical Symptoms in Primary Premature Ejaculation with Paroxetine Treatment

Background

This study aimed to investigate the association between changes in serum 5-hydroxy tryptamine (5-HT) concentrations and improvement in clinical symptoms in primary premature ejaculation with paroxetine treatment.

Material/Methods

A total of 142 men aged 18–65 years with a history of lifelong premature ejaculation and an intravaginal ejaculation latency time (IELT) <120 s were included in this study. Patients were divided into 3 groups according to IELT: IELT ≤30 s (group A), (IELT >30 s and ≤60 s (group B), and IELT >60 s and <120 s (group C). Patients in the 3 groups were administered paroxetine hydrochloride 20 mg/d for 8 weeks. Blood samples were obtained from the candidates in the screening period and after 8 weeks of treatment. Plasma 5-hydroxy-tryptamine (5-HT) concentrations were measured by enzyme-linked immunosorbent assay.

Results

Reliable data from 125 patients were obtained. There were 41 patients in group A, 40 in group B, and 44 in Group C. IELT and serum 5-HT concentrations were significantly improved in the 3 groups after treatment (all P<0.001). The mean change and fold increase in IELT and the mean change in serum 5-HT concentrations in group A were significantly higher than those in groups B and C (all P<0.001). The mean change and fold increase in IELT and the mean change in serum 5-HT concentrations in group B were significantly higher than those in group C (all P<0.001). Significantly more patients in group A achieved clinical benefits than those in groups B and C (P<0.001).

Conclusions

Improvement in serum 5-HT concentrations has obvious association with primary premature ejaculation symptom improvement with paroxetine use.

The role of dapoxetine hydrochloride on-demand for the treatment of men with premature ejaculation

Premature ejaculation (PE) is the most common male sexual dysfunction. Dapoxetine hydrochloride, belonging to a class of drugs known as selective serotonin reuptake inhibitors or, was the first drug originally approved for the on-demand treatment of men with PE. We aimed to compare the intravaginal ejaculatory latency time (IELT), patient-reported global impression of change (PGIC), and adverse effect (AE) incidence associated with the use of dapoxetine (30 mg and 60 mg) versus placebo, and evaluate the differences in administering 60 mg versus 30 mg as on-demand medical oral therapy for the treatment of PE via a literature review and meta-analysis. Relevant randomized controlled trials (RCTs) were identified from PubMed, EMBASE, and Cochrane Central Register of Controlled Trials (Cochrane Library) databases. Ultimately, a total of seven RCTs with 8039 patients were included. Our meta-analysis demonstrated that dapoxetine (in the 30 mg and 60 mg subgroup) resulted in significantly higher IELT, PGIC, and AE incidence relative to the placebo, with higher proportions observed for 60 mg versus 30 mg of dapoxetine administration. The most common AEs were mild and tolerable. We conclude that dapoxetine (particularly the 60 mg dosage) may be considered a safe and effective drug for patients with PE.