Dapoxetine Has No Pharmacokinetic or Cognitive Interactions With Ethanol in Healthy Male Volunteers

Alcohol-medication interactions: A systematic review and meta-analysis of placebo-controlled trials

Alcohol and other xenobiotics may limit the therapeutic effects of medications. We aimed at investigating alcohol-medication interactions (AMI) after the exclusion of confounding effects related to other xenobiotics. We performed a systematic review and meta-analysis of controlled studies comparing the effects induced by alcohol versus placebo on pharmacodynamic and/or pharmacokinetic parameters of approved medications. Certainty in the evidence of AMI was assessed when at least 3 independent studies and at least 200 participants were available. We included 107 articles (3097 participants): for diazepam, cannabis, opioids, and methylphenidate, we found significant AMI and enough data to assign the certainty of evidence. Alcohol consumption significantly increases the peak plasma concentration of diazepam (low certainty; almost 290 participants), cannabis (high certainty; almost 650 participants), opioids (low certainty; 560 participants), and methylphenidate (moderate certainty; 290 participants). For most medications, we found some AMI but not enough data to assign them the certainty grades; for some medications, we found no differences between alcohol and placebo in any outcomes evaluated. Our results add further evidence for interactions between alcohol and certain medications after the exclusion of confounding effects related to other xenobiotics. Physicians should advise patients who use these specific medications to avoid alcohol consumption. Further studies with appropriate control groups, enough female participants to investigate sex differences, and elderly population are needed to expand our knowledge in this field. Short phrases suitable for indexing terms.

Bioequivalence Analysis of 2 Dapoxetine Hydrochloride Formulations in Healthy Chinese Male Volunteers Under Fed and Fasting Conditions: A Randomized, Open-Label, 2-Sequence, 2-Period, 2-Way Crossover Study

This study assessed whether the reference and test formulations of dapoxetine hydrochloride were bioequivalent under fed and fasting conditions postadministration of a single dose as well as evaluated the safety profile of these 2 formulations. This study was a randomized, single-center, 2-period, open-label, 2-way crossover design study with a washout period of 7 days between each period. The study included 80 subjects, 40 under fed and 40 under fasting conditions. During each study period, the subjects were administered a single oral dose of either the reference or the test formulation, followed by collection of plasma samples 70 hours postdose. High-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) was performed to determine the concentrations of dapoxetine in plasma samples along with the calculation of C_max , AUC_0-t, and AUC_0-inf . In addition, adverse events were monitored to determine the safety of these formulations. The geometric mean ratio (90%CI) for the reference and test formulations was 86% to 100%, 89% to 103%, and 89% to 103% under fasting conditions and 92% to 107%, 91% to 100%, and 92% to 101% under fed conditions for C_max , AUC_0-t , and AUC_0-inf , respectively. The 90%CIs for the test/reference ratio for AUC and C_max were within the acceptable limits of bioequivalence, thus demonstrating bioequivalence for these 2 dapoxetine hydrochloride formulations.

One-pot micellar augmented native fluorescence for facile fluorimetric assay of dapoxetine hydrochloride in biological plasma and tablets

One of the medical problems is premature ejaculation which characterized by quick ejaculation and reaching orgasm rapidly. Dapoxetine was accepted as off-label antidepressant used in the treatment of premature ejaculation, so hereby we provide an innovative, non-extractive, environmentally safe protocol for the assay of dapoxetine in biological plasma and tablet. The principle of the assay is simple and only based on native fluorescence which was enhanced by micelle. Parameters influencing the method were optimized and measurements were accomplished at emission wavelength of 338 nm after excitation at 294 nm. The fluorescence-concentration plot was rectilinear over the range of 0.1-4 μg/mL. Directives of ICH guideline were the rules which followed to ensure the validity of the work. Eventually, the procedure was utilized in the dosage form assay and extended to include biological plasma analyses, with good percentage recuperation.

Effects of 22 novel CYP2D6 variants found in Chinese population on the metabolism of dapoxetine

Background

CYP2D6 is one of the most important members of the cytochrome P450 superfamily. Its genetic polymorphism significantly influences the efficacy and safety of some drugs, which might cause adverse effects and therapeutic failure.

Methods and results

The aim of this research was mainly to explore the catalytic activities of 22 newly reported CYP2D6 isoforms (2D6*87, *88, *89, *90, *91, *92, *93, *94, *95, *96,*97, *98, *R25Q, F164L, E215K, F219S, V327M, D336N, V342M, R344Q, R440C, R497C) on dapoxetine in vitro. The research was designed with an appropriate incubation system in test tubes and carried out in the constant temperature water. Through detecting its two metabolites desmethyldapoxetine and dapoxetine-N-oxide, the available data were obtained to explain the influence of CYP2D6 polymorphism on the substrate drug dapoxetine. As a result, the intrinsic clearance (V_max/K_m) values of most variants were significantly altered when compared with the counterpart of CYP2D6*1, with most of these variants exhibiting either reduced V_max and/or increased K_m values. For dapoxetine demethylation pathway (which produces desmethyldapoxetine), 2D6*89 and E215K exhibited no markedly decreased relative clearance of 92.81% and 97.70%, respectively. The relative clearance of rest 20 variants exhibited decrease in different levels, ranging from 20.44% to 90.90%. For the dapoxetine oxidation pathway (which produces dapoxetine-N-oxide), the relative clearance values of three variants, 2D6*90, *94, and V342M, exhibited no markedly increased relative clearance of 106.17%, 107.78%, and 109.98%, respectively; the rest 19 variants exhibited significantly decreased levels ranging from 27.56% to 84.64%. In addition, the kinetic parameters of two CYP2D6 variants (2D6*92 and 2D6*96) could not be detected, due to the defect of the CYP2D6 gene.

Conclusion

As the first report of all aforementioned alleles for dapoxetine metabolism, these data may help in the clinical assessment of the metabolic elimination of dapoxetine and may provide fundamental information for further clinical studies.

The effects of alcohol on the pharmacokinetics and pharmacodynamics of the selective mu-opioid receptor antagonist GSK1521498 in healthy subjects

The mu-opioid system has a key role in hedonic and motivational processes critical to substance addiction. However, existing mu-opioid antagonists have had limited success as anti-addiction treatments. GSK1521498 is a selective and potent mu-opioid antagonist being developed for the treatment of overeating and substance addictions. In this study, 28 healthy participants were administered single doses of GSK1521498 20 mg, ethanol 0.5 g/kg body weight, or both in combination, in a double blind placebo controlled four-way crossover design. The primary objective was to determine the risk of significant adverse pharmacodynamic and pharmacokinetic (PK) interactions. The effects of GSK1521498 on hedonic and consummatory responses to alcohol and the attentional processing of alcohol-related stimuli, and their modulation by the OPRM1 A118G polymorphism were also explored. GSK1521498 20 mg was well tolerated alone and in combination with ethanol. There were mild transient effects of GSK1521498 on alertness and mood that were greater when it was combined with ethanol. These effects were not of clinical significance. There were no effects of GSK1521498 on reaction time, hedonic or consummatory responses. These findings provide encouraging safety and PK data to support continued development of GSK1521498 for the treatment of alcohol addiction.

Dapoxetine: a new option in the medical management of premature ejaculation

Premature ejaculation (PE) is a common male sexual disorder which is associated with substantial personal and interpersonal negative psychological consequences. Pharmacotherapy of PE with off-label antidepressant selective serotonin reuptake inhibitors (SSRIs) is common, effective and safe. Development and regulatory approval of drugs specifically for the treatment of PE will reduce reliance on off-label treatments and serve to fill an unmet treatment need. The objective of this article is to review evidence supporting the efficacy and safety of dapoxetine in the treatment of PE. MEDLINE, Web of Science, PICA, EMBASE and the proceedings of major international and regional scientific meetings were searched for publications or abstracts published during the period 1993-2012 that used the word 'dapoxetine' in the title, abstract or keywords. This search was then manually cross referenced for all papers. This review encompasses studies of dapoxetine pharmacokinetics, animal studies, human phase I, II and III studies, independent postmarketing and pharmacovigilance efficacy and safety studies and drug-interaction studies. Dapoxetine is a potent SSRI which is administered on demand 1-3 h prior to planned sexual contact. It is rapidly absorbed and eliminated, resulting in minimal accumulation, and has dose-proportional pharmacokinetics which are unaffected by multiple dosing. Dapoxetine 30 mg and 60 mg has been evaluated in five industry-sponsored randomized, double-blind, placebo-controlled studies in 6081 men aged at least 18 years. Outcome measures included stopwatch-measured intravaginal ejaculatory latency time (IELT), Premature Ejaculation Profile (PEP) inventory items, Clinical Global Impression of Change (CGIC) in PE, and adverse events. Mean IELT, all PEP items and CGIC improved significantly with both doses of dapoxetine versus placebo (all p <0.001). The most common treatment-related adverse effects included nausea (11.0% for 30 mg, 22.2% for 60 mg), dizziness (5.9% for 30 mg, 10.9% for 60 mg), and headache (5.6% for 30 mg, 8.8% for 60 mg), and evaluation of validated rated scales demonstrated no SSRI class-related effects with dapoxetine use. Dapoxetine, as the first drug developed for PE, is an effective and safe treatment for PE and represents a major advance in sexual medicine.

Efficacy of dapoxetine in the treatment of premature ejaculation

Introduction

Premature ejaculation (PE) is a common male sexual disorder which is associated with substantial personal and interpersonal negative psychological factors. Pharmacotherapy of PE with off-label antidepressant SSRI drugs is common. Development and regulatory approval of drugs specifically for the treatment of PE will reduce reliance on off-label treatments and serve to fill a unmet treatment need.

Aim

To review evidence supporting the efficacy and safety of dapoxetine in the treatment of PE.

Methods

MEDLINE and the proceedings of major international and regional scientific meetings during the period 1994–2010 were searched for publications or abstracts using the word dapoxetine in the title, abstract or keywords. This search was then manually cross-referenced for all papers. This review encompasses studies of dapoxetine pharmacokinetics, animal studies, human phase 1, 2 and 3 efficacy and safety studies and drug-interaction studies.

Results

Dapoxetine is a potent selective serotonin re-uptake inhibitor, which is administered on-demand 1–3 hours prior to planned sexual contact. Dapoxetine is rapidly absorbed and eliminated, resulting in minimal accumulation and has dose-proportional pharmacokinetics, which are unaffected by multiple dosing. Dapoxetine 30 mg and 60 mg has been evaluated in 5 randomized, double-blind, placebo-controlled studies in 6081 men aged ≥18 years. Outcome measures included stopwatch-measured intravaginal ejaculatory latency time (IELT), Premature Ejaculation Profile (PEP) inventory items, clinical global impression of change (CGIC) in PE, and adverse events. Mean IELT, all PEP items and CGIC improved significantly with both doses of dapoxetine vs. placebo (P < 0.001 for all). The most common treatment related adverse effects included nausea (11.0% for 30 mg, 22.2% for 60 mg), dizziness (586% for 30 mg, 10.9% for 60 mg), and headache (5.6% for 30 mg, 8.8% for 60 mg), and evaluation of validated rated scales demonstrated no SSRI class-related effects with dapoxetine use.

Conclusion

Dapoxetine, as the first drug developed for PE, is an effective and safe treatment for PE and represents a major advance in sexual medicine.

Dapoxetine: in premature ejaculation

Dapoxetine, a selective serotonin reuptake inhibitor, is the first oral pharmacological agent indicated for the treatment of men aged 18-64 years with premature ejaculation. In four randomized, double-blind, placebo-controlled, multicentre studies of 12-24 weeks' duration, oral dapoxetine 30 or 60 mg (administered as needed) was effective in the treatment of men with premature ejaculation, inducing significantly (p < 0.001) greater improvements from baseline than placebo in the primary efficacy endpoint (mean intravaginal ejaculatory latency time [IELT] or mean average IELT [defined as the average of IELT values over the previous 4 weeks], as measured by the female partner utilizing a stopwatch). For the most part, dapoxetine recipients achieved significantly better outcomes than placebo recipients with regard to the secondary endpoints, including the Premature Ejaculation Profile (PEP) domains and the Clinical Global Impression or Patient Global Impression ratings of change in premature ejaculation, across these clinical studies. The beneficial effects of dapoxetine therapy on the perceived control over ejaculation and satisfaction with sexual intercourse PEP domains were sustained in a 9-month noncomparative extension phase of two identical 12-week, double-blind studies. Oral dapoxetine therapy for up to 12 months was generally well tolerated in men with premature ejaculation, with the nature of treatment-emergent adverse events generally similar across the clinical studies and between dapoxetine and placebo.

Premature ejaculation: treatment update

Premature ejaculation (PE) is the most common male sexual problem worldwide affecting 22–38% of men. It has a significant morbidity both on patients and their partners, causing distress, anxiety and relationship difficulties. The mainstay of treatment is a combined approach using behavioural therapies and non-licensed medication such as topical anaesthetic preparations, selective serotonin re-uptake inhibitors and phosphodiesterase-5 inhibitors. In recent years, there has been a greater emphasis placed on researching novel treatments and exploring the on-demand use of current preparations. This review provides an overview of current accepted treatments and emerging agents for the use in PE.