Erectile response with vardenafil in sildenafil nonresponders: a multicentre, double-blind, 12-week, flexible-dose, placebo-controlled erectile dysfunction clinical trial

Erectile Dysfunction and Partner-Directed Behaviors in Romantic Relationships: The Mediating Role of Suspicious Jealousy

Erectile dysfunction (ED) has been shown to have a considerable impact on romantic relationships. The purpose of the present research was to examine whether the associations that ED had with men's mate retention behaviors, partner-directed insults, partner-directed violence, and injuries inflicted on the partner were mediated by suspicious jealousy but not reactive jealousy. These associations were examined using self-reports of men (Study 1) and partner-reports provided by women about their perceptions of their male partner (Study 2). The results of both studies indicated that suspicious jealousy (but not reactive jealousy) mediated the associations that ED had with the partner-directed behaviors of men in their romantic relationships. Specifically, higher levels of ED were associated with men experiencing (or being perceived to experience) more suspicious jealousy which, in turn, predicted their use of mate retention behaviors, partner-directed insults, and partner-directed violence as well as the infliction of injuries on their female partners. In our discussion, we address the evolutionary implications of these associations, as well as limitations and directions for future research on ED.

Non-invasive Management Options for Erectile Dysfunction When a Phosphodiesterase Type 5 Inhibitor Fails

Phosphodiesterase type 5 inhibitors (PDE5Is) are the drug of choice for medical management of erectile dysfunction (ED). On-demand PDE5Is have an overall efficacy of 60-70% for ED; 30-35% of patients fail to respond to a PDE5I, and 30-50% of non-responders can be salvaged with detailed counseling on proper use and physician follow-up to ensure that the patient has been prescribed an appropriate and full PDE5I clinical trial. True non-responders may be offered intracavernosal injections of erectogenic drugs, intraurethral alprostadil, or surgical insertion of a penile prosthesis. Such options are not discreet and are associated with more adverse effects than PDE5Is. Thus patients may request additional non-invasive medical management options. This review describes published literature on patients who failed to respond to an on-demand PDE5I regimen and were treated with a non-invasive PDEI-based regimen, including switching from one PDE5I to another; increasing the dose of PDE5I above the labeled dosage range; using two PDE5Is concurrently; using a daily PDE5I regimen; or combining a PDE5I with a testosterone supplement, α-adrenergic antagonist, intraurethral or intracavernosal alprostadil, vacuum erection device, or low-intensity shock wave therapy. The limitations of published clinical trials do not allow for sufficient evidence to recommend one option over another. Therefore, in PDE5I-refractory patients, the choice of a specific next step should be individualized based on the preference of the patient and his sexual partner, the advantages and disadvantages of the various options, the concurrent medical illnesses and medications of the patient, and the patient's response to treatment.

Management of ED under the "severe distress" criteria in the NHS: a real-life study

INTRODUCTION

The United Kingdom is unusual in that a significant proportion of patients with erectile dysfunction (ED) have their treatment fully reimbursed by the National Health Service (NHS). This may have consequences for the choice of treatment and for compliance with treatment.

AIMS

The aim of this study was to evaluate the use and cost implications of phosphodiesterase type 5 inhibitor in an NHS setting.

METHODS

Basic demographics and data on ED management for patients treated from January 2000 to April 2011 were obtained from a prospectively accrued database. We reviewed drug usage and costs as well as switching between drugs. Patients were given the choice of all available therapies and were followed up annually.

MAIN OUTCOME MEASURES

Switching, compliance, and costs of treating ED under the "severe distress" criteria in the NHS were reviewed for this study.

RESULTS

Two thousand one hundred fifty-nine patients qualified for reimbursed therapy. Two hundred twenty-six patients were excluded from further analysis owing to missing data. Patients were followed up on an annual basis. The mean patient age was 60.2 years (min 23, max 90), and the mean follow-up was 50.8 months (min 1, max 127). Six hundred ninety-six were started on sildenafil, 990 on tadalafil, 163 on vardenafil, and 84 on intracavernosal alprostadil. Eighteen percent of patients initially started on the scheme and stopped medication unilaterally. Of the patients, 12.3% changed their medication during follow-up. The cost of drugs increased year by year from £257,100 in 2007 to £352,519 in 2011.

CONCLUSIONS

Our real-life observational study shows that in our institution, dropout of therapy is unusual. We hypothesize that this reflects, in part, the reimbursement issue. We also found that switching between drugs was unusual, although there are several possible explanations for that. Although this is a successful system for the patients, the hospital, which bears the costs of medication, is finding this an increasing economic drain.

Reasons and predictive factors for discontinuation of PDE-5 inhibitors despite successful intercourse in erectile dysfunction patients

This study was aimed to identify characteristics of ED patients who discontinued PDE5i despite successful intercourse. Data were collected using a questionnaire from 34 urologic clinics regardless of the effect (success or failure) of PDE5i treatment by visiting the clinics (717), e-mail (64) or post (101) for 882 ED patients who had previously taken any kind of PDE5i on demand four or more times. Discontinuation of PDE5i was defined if the patient had never taken PDE5i for the previous 1 year despite successful intercourse. Of the 882 patients, 485 were included in the final analysis. Difference in the socio-demographic, ED- and partner-related data between the continuation and discontinuation group and factors influencing discontinuation of the PDE5i were analyzed. Among 485 respondents (mean age, 53.6), 116 (23.9%) had discontinued PDE5i use despite successful intercourse. Most common reasons for the discontinuation were ‘reluctant medication-dependent intercourse' (31.0%), ‘spontaneous recovery of erectile function without further treatment' (30.2%), and ‘high cost' (26.7%). In multiple logistic regression analysis, independent factors influencing discontinuation of the drug were cause of ED (psychogenic), short duration of ED, low education (⩽ middle school), and religion (Catholic). In partner-related compliance, only partner's religion (Catholic) was a significant factor.

Phosphodiesterase type 5 inhibitors as a treatment for erectile dysfunction: Current information and new horizons

INTRODUCTION

Over the past 15 years, the discovery and development of oral medications that selectively inhibit the enzyme phosphodiesterase type 5 (PDE5) have revolutionised the treatment of erectile dysfunction (ED). Currently, three PDE5 inhibitors are widely available clinically, i.e., sildenafil, vardenafil and tadalafil. New PDE5 inhibitors, including avanafil and udenafil, are now in clinical use in a few countries, and other compounds are under development.

METHODS

We describe the current use and future direction of PDE5 inhibitors in the treatment of ED.

RESULTS AND CONCLUSION

Each PDE5 inhibitor has an excellent and comparable efficacy and tolerability. These drugs are highly effective for ED of various causes, and are effective in preventing ED after radical prostatectomy. However, whilst being at least 60% effective, PDE5 inhibitors are still ineffective in at least 30% of patients, prompting current research into other pharmacological targets for ED.

Non-invasive management of primary phosphodiesterase type 5 inhibitor failure in patients with erectile dysfunction

Phosphodiesterase type 5 inhibitors (PDE5-i) have become first line therapy for the treatment of erectile dysfunction. Most initial prescriptions for PDE5-i are by primary care practitioners. Urologists must now routinely manage the patient who has failed initial therapy with PDE5-i. Lifestyle modifications can be of benefit to patients. Patient education and optimization of the PDE5-i can result in a successful response. Interestingly, there are reports of up to 60% salvage after changing the PDE5-i utilized. Daily PDE5-i have shown benefit, and treatment of hypogonadism can enhance response to PDE5-i. We review the management of PDE5-i failures with emphasis on noninvasive approaches to gaining improved erectile response to these medications. An algorithm based on the reviewed strategies is proposed to guide clinicians in the treatment of erectile dysfunction.

Dopamine and oxytocin interactions underlying behaviors: potential contributions to behavioral disorders

Dopamine is an important neuromodulator that exerts widespread effects on the central nervous system (CNS) function. Disruption in dopaminergic neurotransmission can have profound effects on mood and behavior and as such is known to be implicated in various neuropsychiatric behavioral disorders including autism and depression. The subsequent effects on other neurocircuitries due to dysregulated dopamine function have yet to be fully explored. Due to the marked social deficits observed in psychiatric patients, the neuropeptide, oxytocin is emerging as one particular neural substrate that may be influenced by the altered dopamine levels subserving neuropathologic-related behavioral diseases. Oxytocin has a substantial role in social attachment, affiliation and sexual behavior. More recently, it has emerged that disturbances in peripheral and central oxytocin levels have been detected in some patients with dopamine-dependent disorders. Thus, oxytocin is proposed to be a key neural substrate that interacts with central dopamine systems. In addition to psychosocial improvement, oxytocin has recently been implicated in mediating mesolimbic dopamine pathways during drug addiction and withdrawal. This bi-directional role of dopamine has also been implicated during some components of sexual behavior. This review will discuss evidence for the existence dopamine/oxytocin positive interaction in social behavioral paradigms and associated disorders such as sexual dysfunction, autism, addiction, anorexia/bulimia, and depression. Preliminary findings suggest that whilst further rigorous testing has to be conducted to establish a dopamine/oxytocin link in human disorders, animal models seem to indicate the existence of broad and integrated brain circuits where dopamine and oxytocin interactions at least in part mediate socio-affiliative behaviors. A profound disruption to these pathways is likely to underpin associated behavioral disorders. Central oxytocin pathways may serve as a potential therapeutic target to improve mood and socio-affiliative behaviors in patients with profound social deficits and/or drug addiction.

Effects of sildenafil and vardenafil on erectile dysfunction and health-related quality of life in haemodialysis patients: a prospective randomized crossover study

BACKGROUND

Erectile dysfunction (ED) is prevalent in end-stage renal disease (ESRD) and has been associated with impaired health-related quality of life (HRQoL). HRQoL, in turn, is related to morbidity and mortality in ESRD patients. Previous studies have shown improved HRQoL with ED treatment using sildenafil and vardenafil. However, no study has examined the effects of sildenafil or vardenafil on HRQoL in impotent ESRD patients. Furthermore, vardenafil has never been tested and its safety profile has not been determined in ESRD patients. The aim of this randomized crossover study was to compare the effects of sildenafil and vardenafil on measures of HRQoL and on ED scores as well as to determine the safety profile of vardenafil in ESRD patients.

METHODS

In 32 haemodialysis patients with impotence, ED and HRQoL were evaluated by the International Index of Erectile Function (IIEF-5) and the 36-item Short-Form Health (SF-36) surveys, respectively. Patients were randomized into sildenafil and vardenafil groups. After a 4-week treatment and 2-week washout periods, crossover was performed and an additional 4-week treatment was administered. IIEF-5 and SF-36 surveys were given before and after each treatment period. Adverse effects were evaluated by interview. Friedman tests and Bonferroni-adjusted Wilcoxon signed-rank tests were used to compare groups and for post hoc analysis, respectively.

RESULTS

IIEF-5 and SF-36 scores were significantly improved by both sildenafil and vardenafil compared to pretreatment values. There were no differences between sildenafil and vardenafil with respect to the studied parameters. Adverse effect profiles were also similar. No patient dropped out because of side effects.

CONCLUSIONS

Sildenafil and vardenafil caused similar improvements in ED and HRQoL in haemodialysis patients. Vardenafil was well tolerated in our patient population.

Vardenafil improves erectile function in men with erectile dysfunction and associated underlying conditions, irrespective of the use of concomitant medications

INTRODUCTION

Men with erectile dysfunction (ED) are also likely to have associated underlying conditions.

AIM

This retrospective analysis evaluated the efficacy and safety of vardenafil in men with ED and underlying conditions, including those taking concomitant medications.

METHODS

A total of 13 randomized, double-blind, placebo-controlled clinical studies were included. Vardenafil was administered at a starting dose of 10 mg, adjustable to 5 or 20 mg after 4 weeks. Efficacy analyses were performed on the intent-to-treat (ITT) population, using a last observation carried forward approach. Efficacy was assessed for subgroups of patients with diabetes, hypertension, dyslipidemia, or metabolic syndrome (as defined by International Diabetes Federation criteria). Incidence rates of treatment-emergent adverse events were analyzed overall and by subgroup for patients in the safety population.

MAIN OUTCOME MEASURES

Primary efficacy measures were the erectile function domain of the International Index of Erectile Function (IIEF-EF), and Sexual Encounter Profile questions 2 and 3 (SEP2, SEP3).

RESULTS

In total, 4,326 patients were randomized to treatment; the ITT population included 4,143 patients, with 4,266 patients valid for safety. At 12 weeks, vardenafil therapy was associated with statistically significant improvements from baseline in IIEF-EF scores, and SEP2 and SEP3 success rates, including patients with ED and diabetes, hypertension, dyslipidemia, or metabolic syndrome. These improvements were irrespective of level of glycemic control, or use of concomitant medications for the treatment of diabetes, hypertension, or dyslipidemia. Across all subgroups, the number and type of treatment-emergent adverse events were consistent with results from previous studies of phosphodiesterase type 5 inhibitors in men with ED and underlying conditions.

CONCLUSIONS

Vardenafil demonstrated favorable efficacy and tolerability in this large pool of patients with ED and underlying conditions. Importantly, the use of concomitant medications was not associated with any noteworthy changes in the efficacy or safety profile of vardenafil.

Platelet cyclic guanosine monophosphate as a biomarker of phosphodiesterase type 5 inhibitor efficacy in the treatment of erectile dysfunction: a randomized placebo-controlled study

BACKGROUND

Phosphodiesterase 5 inhibitors (PDE5-Is) are a mainstay in the therapy of erectile dysfunction (ED). The primary end point of clinical efficacy, both in clinical studies and normal practice, is represented by the International Index of Erectile Function (IIEF).

OBJECTIVE

To evaluate if platelet cyclic guanosine monophosphate (cGMP) could represent a valuable marker for PDE5-I activity in ED.

DESIGN, SETTING, AND PARTICIPANTS

The study enrolled 46 patients with psychogenic, organic, and mixed ED (20-71 yr of age; IIEF score<26). Patients were randomized to 6 wk of vardenafil, 5 mg/d at bedtime, or placebo.

INTERVENTION

All patients donated two blood samples, one before starting the protocol and the second after 6 wk of treatment.

MEASUREMENTS

Platelet cGMP was measured in both placebo and vardenafil groups. All the patients completed the IIEF-Erectile Function (EF) domain and the sexual encounter profile (SEP) and underwent visual sexual stimulation (VSS) coupled with Rigiscan. All the measurements were performed prior to starting the protocol and after the 6 wk of treatment.

RESULTS AND LIMITATIONS

Platelet cGMP production was significantly (p<0.05) elevated in patients taking 5mg vardenafil versus placebo. Vardenafil was not superior to placebo in improving IIEF-EF and SEP scores. Conversely, VSS-Rigiscan revealed a significant amelioration (p<0.028) in the vardenafil group versus placebo. The changes in platelet cGMP level correlated well with VSS-Rigiscan (p=0.0037) but not with IIEF-EF and SEP.

CONCLUSIONS

Platelet cGMP could represent a relatively simple, reliable, and objective biomarker of PDE5-I activity in ED clinical studies. Larger clinical studies are needed to further validate the use, utility, and limits of this assay.

Toward a new 'EPOCH': optimising treatment outcomes with phosphodiesterase type 5 inhibitors for erectile dysfunction

Despite the marked adverse impacts of erectile dysfunction (ED) on quality of life and well-being, many patients (and/or their partners) do not seek medical attention for this problem, do not receive treatment or discontinue such treatment even when it has effectively restored erectile responses to sexual stimulation. Phosphodiesterase type 5 (PDE5) inhibitors are considered first-line therapies for men with ED. To help physicians maximise the likelihood of treatment success with these agents, we conducted an English-language PubMed search of articles involving approved PDE5 inhibitors dating from 1 January 1998 (the year in which sildenafil citrate was introduced), through 31 August 2008. In addition to sildenafil, tadalafil and vardenafil, search terms included 'adhere*', 'couple*', 'effect*', 'effic*', 'partner*', 'satisf*', 'succe*' and 'treatment outcome.' Based on our analysis, physician activities to promote favourable treatment outcomes may be captured under the mnemonic 'EPOCH': (i) Evaluating and educating patients and partners to ensure realistic expectations of therapy; (ii) Prescribing a treatment individualised to the couple's lifestyle needs and other preferences; (iii) Optimising treatment outcomes by scheduling follow-up visits with the patient to 'fine-tune' dosages and revisit key educational messages; (iv) Controlling comorbidities via lifestyle counselling, medications and/or referrals and (v) Helping patients and their partners to meet their health and psychosocial needs, potentially referring them to a specialist for other forms of therapy if they are not satisfied with PDE5 inhibitors.

Effect of the phosphodiesterase 5 inhibitors sildenafil, tadalafil and vardenafil on rat anococcygeus muscle: functional and biochemical aspects

1. The anococcygeus muscle is part of the erectile machinery in male rodents. Phosphodiesterase (PDE) 5 inhibitors enhance and prolong the effects of cGMP, which has a key role in penile erection. The aim of the present study was to provide a functional and biochemical comparison of the three PDE5 inhibitors, namely sildenafil, tadalafil and vardenafil, in the rat anococcygeus muscle. 2. Muscle strips were mounted in 4 mL organ baths and isometric force recorded. Levels of cGMP were measured using an enzyme immunoassay kit. Western blots were used to determine PDE5 protein expression. 3. The PDE5 inhibitors concentration-dependently relaxed carbachol-precontracted anococcygeus muscle; however, vardenafil was more potent (pEC(50) = 8.11 +/- 0.05) than sildenafil (7.72 +/- 0.06) or tadalafil (7.69 +/- 0.05). Addition of N(G)-nitro-l-arginine methyl ester (100 micromol/L) or 1H-[1,2,4]oxadiazolo[4,3-a]quinoxalin-1-one (10 micromol/L) to the organ baths caused significant rightward shifts in concentration-response curves for all PDE5 inhibitors. 4. Sildenafil, tadalafil and vardenafil (all at 0.1 micromol/L) caused leftward shifts in the glyceryl trinitrate (GTN) concentration-response curves (by 4.0-, 3.7- and 5.5-fold, respectively). In addition, all three PDE5 inhibitors significantly potentiated relaxation responses to both GTN (0.01-10 micromol/L) and electrical field stimulation (EFS; 1-32 Hz), with vardenafil having more pronounced effects. 5. All three PDE5 inhibitors reduced EFS-evoked contractions in a concentration-dependent manner over the concentration range 0.001-1 micromol/L. There were no significant differences between the effects of the three PDE5 inhibitors. 6. Vardenafil (0.01-0.1 micromol/L) was more potent in preventing cGMP degradation in vitro than sildenafil (0.01-0.1 micromol/L) and tadalafil (0.01-0.1 micromol/L). 7. Under control conditions, the expression of PDE5 was higher in the anococcygeus muscle than in the corpus cavernosum. 8. In conclusion, PDE5 inhibitors enhance exogenous and endogenous nitric oxide-mediated relaxation in the rat anococcygeus muscle. The potency of vardenafil was greater than that of either sildenafil or tadalafil.

Efficacy of vardenafil for the treatment of erectile dysfunction in men with hypertension: a meta-analysis of clinical trial data

OBJECTIVE

To review the evidence evaluating the efficacy of vardenafil in subgroups of hypertensive patients with erectile dysfunction (ED).

METHODS

Meta-analysis of randomized, double-blinded, placebo-controlled, flexible-dose vardenafil clinical trials that were >or=12 weeks in duration evaluated men with a >or=6-month history of ED and required a >or=50% failure rate in baseline sexual attempts. The primary endpoints analyzed were the erectile function domain of the International Index of Erectile Function questionnaire (IIEF-EF) and Sexual Encounter Profile questions 2 (SEP2) and 3 (SEP3).

RESULTS

Eight clinical trials were included (n = 2427 patients) consisting of 839 patients (35%) with a self-reported diagnosis of hypertension (HTN): 498 in the vardenafil and 341 in the placebo groups. Vardenafil's efficacy was evidenced by an average increase of 8.9 points in the IIEF-EF (95% CI: 7.4, 10.5) at week 12 compared to placebo, with individual trial values ranging from 16.4 to 26.1 and 11.3 to 17.8 for the vardenafil and placebo groups, respectively. Vardenafil also increased success rates for the ability to obtain erections (SEP2) by 32.4% (95% CI: 27.4%, 37.5%) over a 12-week timeframe compared to placebo, with individual trial values ranging from 57.2% to 92.2% for vardenafil and 32.0% to 66.9% for placebo. Similarly, success rates for the ability to maintain erections (SEP3) improved 38.0% (95% CI: 29.5%, 46.6%) compared to placebo, with individual trial values ranging from 41.7% to 88.2% for vardenafil and 20.5% to 51.4% for placebo. Vardenafil was equally efficacious in improving IIEF-EF, SEP2, and SEP3 in those with and without self-reported HTN.

CONCLUSION

This meta-analysis demonstrated that vardenafil was significantly more efficacious than placebo for the treatment of ED in patients with comorbid HTN and offered similar treatment benefits in patients without HTN.

The COUPLES-project: a pooled analysis of patient and partner treatment satisfaction scale (TSS) outcomes following vardenafil treatment

OBJECTIVE

To assess the influence of vardenafil on treatment satisfaction in men with erectile dysfunction (ED) and their female partners.

PATIENTS AND METHODS

This was a pooled analysis of three randomized, double-blind, placebo-controlled, 12-week studies of flexible-dose vardenafil vs placebo, in men with ED for >/=6 months (n = 788) and their untreated female partners. Measures of efficacy included the Treatment Satisfaction Scale (TSS), International Index of Erectile Function, Erectile Function domain (IIEF-EF), and Sexual Encounter Profile (SEP) questions 2 and 3 (SEP-2, 'Were you able to insert your penis into your partner's vagina?'; and SEP-3, 'Did your erection last long enough for you to have sexual intercourse?'). In addition to the overall analysis, there was a subgroup analysis for potential moderators of response, e.g. whether patients who had undergone previous phosphodiesterase type 5 (PDE-5) treatment.

RESULTS

At baseline, least-squares (LS) mean scores for all TSS domains were similar in the vardenafil and placebo groups. After 12 weeks of treatment, vardenafil significantly improved the LS mean score for all domains compared with placebo, among both patients and their female partners (P < 0.0001, 'last'-observation-carried- forward analysis). Absolute between- group differences in LS mean TSS scores (vardenafil - placebo) were: ease of erection (patients 23.4, partners 24.9), erectile function satisfaction (36.7 and 32.9), pleasure from sexual activity (23.0, 23.7), satisfaction with orgasm (27.6, 21.8), confidence to complete sexual activity (28.2, 32.5), and satisfaction with medication (37.4, 35.6). The benefits of vardenafil were greater in men who had undergone previous PDE-5-inhibitor treatment and men aged <45 years, while the overall pattern of benefit was similar in all examined subgroups. There were significant benefits with vardenafil in all other variables (IIEF-EF scores and positive response rates to SEP-2 and SEP-3).

CONCLUSIONS

Vardenafil significantly improved treatment satisfaction in men with ED, and in their partners. The results provide further evidence of the validity of the TSS.

The Real-Life Safety and Efficacy of Vardenafil

OBJECTIVE

To assess the safety, efficacy and patient acceptability of vardenafil treatment under real-life conditions in patients with erectile dysfunction (ED).

METHODS

The present publication shows the results of a subgroup analysis of a multinational post-marketing surveillance study, including 2824 Middle East patients with ED whose attending physician chose vardenafil as the most appropriate therapy. Patients were assessed at an initial visit for demographic and baseline characteristics. At one or two follow-up visits, covering a period of approximately 2 months or eight vardenafil intakes, patients were interviewed about overall treatment success (general improvement of erection, number of tablets taken until improvement, patient's satisfaction with overall efficacy and tolerability, comparison with last ED treatment). All adverse events were recorded and assessed for a possible relationship to treatment, and for severity.

RESULTS

An overall improvement in erections was reported in 94.3% of patients. Most patients achieved treatment success after the first (67.0%) or second (83.6% cumulative) tablet. Diabetic patients had a similar improvement rate (92.2%) and 73.5% of patients who had undergone radical prostatectomy reported an overall improvement. The rate of adverse drug reactions (ADRs) was low (9.1% of patients). The most common ADRs were headache (5.8%), flushing (1.6%), nasal congestion (1.0%), dyspepsia (0.6%) and nausea (0.5%). In total, 88.9% of patients wanted to continue treatment with vardenafil.

CONCLUSION

Vardenafil was effective, reliable and well tolerated in patients with ED treated under real-life conditions.

Do vardenafil and tadalafil have advantages over sildenafil in the treatment of erectile dysfunction?

Erectile dysfunction (ED) affects up to 50% of men between the ages of 40 and 70 years of age. Sildenafil, vardenafil and tadalafil have all been shown to be similarly effective in the treatment of men with ED of vary etiologies, to have similar adverse effects profiles, and to improve quality-of-life by similar amounts. As these phosphodiesterase 5 (PDE5) inhibitors all increase the hypotensive effects of nitrates, they are not suitable for use in patients taking nitrates for the treatment of ischaemic heart disease. All three inhibitors must be used with caution in patients taking alpha(1)-adrenoceptors antagonists for benign prostatic hyperplasia. Although nonarteritic anterior ischaemic neuropathy has been reported in some users of the PDE5 inhibitors, there is no conclusive evidence that PDE5 inhibitors cause this rare effect. Tadalafil has a longer half-life than sildenafil or vardenafil, and a longer duration of action than sildenafil and vardenafil. Most preference studies have shown tadalafil to be preferred, but there are serious limitations to some of these studies. One approach to treatment is to give each patient a short- and long-acting agent, and for individuals to decide their preference.

Vardenafil improved erectile function in a "real-life" broad population study of men with moderate to severe erectile dysfunction in Australia and New Zealand

INTRODUCTION

Phosphodiesterase type 5 inhibitor drugs produce vasodilatation by inhibiting the breakdown of cyclic guanosine monophosphate and have proven efficacy in treating erectile dysfunction (ED).

AIM

To evaluate the efficacy, safety, and tolerability of vardenafil in men with moderate to severe ED of broad etiology.

MAIN OUTCOME MEASURES

The erectile function (EF) domain score, the response to Questions 13 and 14 of the International Index of Erectile Function (IIEF) questionnaire, and the proportion of "yes" responses to questions 2 and 3 of the Sexual Encounter Profile (SEP), a Global Assessment (GAQ), and Global Satisfaction Questions (GSQ) were compared at baseline and at 12 weeks of treatment with as-needed vardenafil.

METHODS

A total of 326 subjects with a mean age of 57.6 years and moderate to severe erectile dysfunction of various etiologies received vardenafil (5-20 mg) for 12 weeks in a prospective multicenter, open-label flexible-dose study.

RESULTS

Compared with baseline, vardenafil was superior in all efficacy outcomes. A significant mean improvement of 13.4 (P < 0.001) in the EF domain from baseline was obtained at week 12. Subjects who received 5, 10, and 20 mg vardenafil at week 12 experienced improvements of 11.9, 15.1, and 12.9 respectively in the EF domain score. Sexual intercourse was successfully completed (SEP3) in 76.3%, 80.1%, and 74.3% of subjects receiving 5, 10, and 20 mg vardenafil compared with 25.9%, 17.9%, and 19.2% at baseline, respectively. For all doses combined at week 12, the change in SEP3 from baseline was 56.7% (P < 0.001). Treatment with vardenafil was well tolerated, and headaches, flushing, nasal congestion, and dyspepsia were the most frequently observed adverse events.

CONCLUSIONS

Vardenafil was effective and well tolerated in men with moderate to severe erectile dysfunction. Treatment with vardenafil was associated with a significantly higher IIEF erectile function domain score and completion of successful intercourse rate compared with baseline.

Up-titration of vardenafil dose from 10 mg to 20 mg improved erectile function in men with spinal cord injury

AIM

Vardenafil is a highly selective phosphodiesterase type-5 inhibitor for the treatment of erectile dysfunction (ED). Efficacy of vardenafil has been demonstrated in various ED populations, but that in Japanese patients with spinal cord injury (SCI) has not been assessed.

METHODS

This was an open-label, multicenter, flexible dose, 12-week study in patients with ED due to SCI. Following a 4-week observation period, patients received vardenafil 10 mg for 4 weeks, and based on efficacy, tolerability and patient preference, doses for the remaining 8 weeks were decided by investigators. The primary efficacy parameter was erectile function domain score of the International Index of Erectile Function.

RESULTS

Ten patients took 10 mg all through the study, while 22 patients took 20 mg after completing 4 weeks' treatment with 10 mg. The erectile function domain score increased from 12.2 at baseline to 25.0 at Last Observation Carried Forward (LOCF) in the former group and from 10.3 to 22.5 in the latter group, respectively. Importantly, there was a 5.0 point increase in erectile function domain score after up-titration in the latter group. Drug-related adverse events were observed in 22% of patients including hot flushes (9%) and headache (6%), but these were transient and mild in intensity. Serious adverse events and adverse events leading to discontinuation of the study drug were not reported.

CONCLUSIONS

Vardenafil 10 and 20 mg was well tolerated and improved erectile function in patients with SCI. Of interest, erectile function was further improved by 20 mg in patients who were not sufficiently treated with 10 mg.

Management of sildenafil treatment failures

PURPOSE OF REVIEW

Although oral type 5 phosphodiesterase inhibitors are considered as first-line therapy for the majority of causes of erectile dysfunction, because of their high efficacy, ease of use, and acceptable safety profile, there are some who fail to respond, mainly because of end-organ failure. This communication reviews the management of sildenafil failures in light of recent advances.

RECENT FINDINGS

Sildenafil failures can be attributed to either lack of efficacy or side effects; issues may involve the physician, patient, and his partner. Physicians may contribute to sildenafil failure and discontinuation because of inadequate instructions, lack of adequate follow-up, suboptimal dosing, lack of adequate trial, and insufficient clarification about safety issues. Studies have demonstrated that progression of endothelial dysfunction and diminished cavernosal smooth-muscle content are recognized organic factors which cause end-organ dysfunction and ultimately treatment failure.

SUMMARY

Proper counseling, medication optimization, and modifying associated risk factors can provide success in men who had initially failed sildenafil therapy for erectile dysfunction. Other treatment modalities that may be considered when sildenafil failure occurs include vacuum devices, intraurethral, and intracavernosal administration of vasoactive drugs alone or combined with sildenafil. Penile prosthesis implantation is considered as a last resort, if all first-line and second-line therapies fail.

Extended Duration of Efficacy of Vardenafil When Taken 8 Hours Before Intercourse: A Randomized, Double-Blind, Placebo-Controlled Study

OBJECTIVES

This study explored the efficacy of vardenafil in men with erectile dysfunction (ED) when taken 8 hours before sexual intercourse.

METHODS

A 10-week, randomized, double-blind, placebo-controlled, parallel-group, flexible-dose study of vardenafil (5, 10 or 20mg) was conducted in men with ED for >6 months who failed >or=50% of intercourse attempts during a 4-week treatment-free run-in period. Sexual Encounter Profile Question 3 (SEP3) was the primary efficacy measure; secondary measures included SEP2, International Index of Erectile Function-Erectile Function (IIEF-EF) domain score, Global Assessment Question (GAQ), Global Confidence Question (GCQ) and Erection Quality Scale (EQS). Adverse-event and safety monitoring were conducted throughout.

RESULTS

383 patients were randomized to vardenafil (n=194) or placebo (n=189). Patients treated with vardenafil 8 hours before sexual activity achieved clinically meaningful (>or=18%) and statistically significantly greater least-squares mean per-patient SEP3 and SEP2 success rates over weeks 2-10, compared with patients receiving placebo (SEP3 69% vs 34%; SEP2 81% vs 51%; both p<0.001). SEP3 and SEP2 measures demonstrated the significant superiority of vardenafil over placebo from week 2 onwards (p<0.001). Measurements of IIEF-EF domain score, GAQ, GCQ and EQS showed that vardenafil led to significantly greater improvements in erectile function, compared with placebo (all p<0.001). Vardenafil was generally well tolerated.

CONCLUSIONS

The extended duration of efficacy of vardenafil up to 8 hours postdose may provide couples with more flexibility in their sexual life than anticipated.

Vardenafil rescue rates of sildenafil nonresponders: Objective assessment of 327 patients with erectile dysfunction

OBJECTIVES

To prospectively investigate whether vardenafil can effectively treat patients for whom sildenafil (100 mg) has failed. The introduction of two new oral phosphodiesterase type 5 inhibitors (tadalafil and vardenafil) raises the question of whether the new agents will permit us to treat sildenafil nonresponders with another oral agent.

METHODS

Patients were seen at one institution during a 5-year period. A total of 327 patients complaining of sildenafil-refractory erectile dysfunction underwent intracavernous pharmacologic injection and color duplex Doppler ultrasonography. Subsequently 59 of these men tried vardenafil home dosing.

RESULTS

Of the 327 men in whom sildenafil failed, 16% were younger than 50, 21% were 51 to 60, 34% were 61 to 70, and 28% were older than 70 years. The Doppler diagnoses were arterial insufficiency in 154 (47%), mixed vascular insufficiency in 73 (22%), and cavernous venous occlusive disease in 57 (17%). Forty-three men (13%) had normal erectile responses to prostaglandin E1 (10 to 20 microg). Of the 59 men who tried vardenafil, 19% were younger than 50, 17% were 51 to 60, 40% were 61 to 70, and 23% were older than 70 years. The Doppler diagnoses were arterial insufficiency in 28 (42%), mixed vascular insufficiency in 10 (19%), and cavernous venous occlusive disease in 15 (29%). Six men (8%) had normal erectile responses to prostaglandin E1. Only 7 (12%) of the 59 men reported that home vardenafil dosing resulted in successful intercourse.

CONCLUSIONS

An appropriate diagnostic evaluation and subsequent treatment algorithm have yet to be established for those for whom phosphodiesterase type 5 inhibitors fail. We found that most sildenafil nonresponders had severe arterial insufficiency and were older, with 62% older than 60 years. Our preliminary experience suggests that only a small percentage (12%) of sildenafil nonresponders can be salvaged with vardenafil.

Efficacy of tadalafil in Egyptian and Turkish men with erectile dysfunction

A randomised, double-blind, parallel, placebo-controlled, 12-week study was carried out to evaluate the efficacy and safety of 20-mg tadalafil taken 'as needed' in a population of men with erectile dysfunction (ED) from Egypt and Turkey. One hundred and thirty-two patients were randomised in this study. Tadalafil was superior to placebo on all three co-primary efficacy end points. The mean change from baseline for the erectile function domain of the International Index of Erectile Function was 9.3 +/- 0.8 for the tadalafil group and 2.3 +/- 1.6 for the placebo group. Tadalafil-treated patients reported a significantly greater improvement in the mean percentage of successful penetrations (tadalafil: 34.5 +/- 4.1; placebo: -4.6 +/- 8.1) and successful intercourse attempts (tadalafil: 52.2 +/- 3.8; placebo: 16.8 +/- 7.8) than placebo-treated patients as measured by the Sexual Encounter Profile. Tadalafil was generally well tolerated with 82% of adverse events being mild in severity. Tadalafil 20-mg taken 'as needed' significantly improved the erectile function in Egyptian and Turkish men with ED.

Efficacy and Safety of Vardenafil in Renal Transplant Recipients With Erectile Dysfunction

Erectile dysfunction (ED) profoundly affects the quality of life. The prevalence of ED in renal transplant recipients is reported by high as 50% to 60%. We evaluated the efficacy and safety of vardenafil in these patients with ED as well as its effects on graft function and on cylosporine or tacrolimus concentrations. Thirty-nine recipients with ED and serum creatinine values<2 mg/dL were treated with vardenafil. ED was assessed using the self-administered International Index of Erectile Function (IIEF). ED was diagnosed by using penile color-Doppler ultrasonography and intracavernosal injection. Vardenafil efficacy was assessed by readministering the IIEF questionnaire after 4 weeks of therapy. Serum creatinine levels, creatinine clearances, and cyclosporine/tacrolimus concentrations were measured before and after vardenafil therapy. Twenty-one recipients with ED served as placebo controls and 15 without ED as another control group. The IIEF scores improved from 12.80+/-3.5 to 26.46+/-2.4 in vardenafil-treated patients with ED (P<.001). Renal function and cyclosporine/tacrolimus concentrations did not change with vardenafil therapy. Side effects were observed in 7 (18%) patients: headache in three, palpitations in one, flushing in two, and dyspepsia in one. This study demonstrated that ED improved with vardenafil in renal transplant recipients with ED. For 4 weeks vardenafil therapy was free of side effects. Renal function tests did not change. Also, no dose change in immunosuppressive drugs was required during 4 weeks of verdanafil therapy.

Medication utilization behavior in patients receiving phosphodiesterase type 5 inhibitors for erectile dysfunction

INTRODUCTION

A number of preference studies have been conducted with phosphodiesterase type 5 (PDE5) inhibitor medications demonstrating inconsistent findings. Additionally, limited information is available regarding real-world utilization patterns of PDE5 inhibitors.

AIM

To evaluate treatment patterns using real-world data for patients initiating erectile dysfunction (ED) therapy with Viagra (sildenafil citrate), Levitra (vardenafil), or Cialis (tadalafil).

METHODS

Patients with an initial prescription claim for sildenafil, vardenafil, or tadalafil were identified in NDCHealth's Intelligent Health Repository. Medication refills, medication switching, and dose titration were analyzed. Logistic regression on the odds of refilling initial PDE5 medications was conducted controlling for patient age, presence of common comorbidities, initial number of tablets, and copay.

RESULTS

A higher percentage of patients receiving sildenafil (52%) refilled their ED medication during the study period than patients receiving vardenafil (30%) or tadalafil (29%) (P<0.001). A smaller percentage of patients in the sildenafil cohort (6.4%) switched medication than in the tadalafil (9.0%) or vardenafil (10.4%) cohorts (P<0.001); the difference between the tadalafil and vardenafil cohorts in switching medications was also significant (P<0.001). There were no statistically significant differences between cohorts in dose titration frequency, which was low in all three treatment cohorts. Using logistic regression, the odds of refilling initial PDE5 therapy was significantly lower for vardenafil (odds ratio [OR]: 0.39, 95% confidence interval [CI]: 0.38-0.40; P<0.0001) and tadalafil (OR: 0.38, 95% CI: 0.37-0.40; P<0.0001) compared with sildenafil.

CONCLUSIONS

Patients who were initially prescribed sildenafil were significantly more likely to refill their medication and significantly less likely to switch medications during the study period compared with patients who were initially prescribed vardenafil or tadalafil. These findings may indicate greater treatment satisfaction in patients receiving sildenafil, although future prospective evaluation is required.

Indirect comparison of interventions using published randomised trials: systematic review of PDE-5 inhibitors for erectile dysfunction

BACKGROUND

There are no randomised and properly blinded trials directly comparing one PDE-5 inhibitor with another in a normal home setting. Valid indirect comparisons with a common comparator must examine equivalent doses, similar duration, similar populations, with the same outcomes reported in the same way.

METHODS

Published randomised, double-blind trials of oral PDE-5 inhibitors for erectile dysfunction were sought from reference lists in previous reviews and electronic searching. Analyses of efficacy and harm were carried out for each treatment, and results compared where there was a common comparator and consistency of outcome reporting, using equivalent doses.

RESULTS

Analysis was limited by differential reporting of outcomes. Sildenafil trials were clinically and geographically more diverse. Tadalafil and vardenafil trials tended to use enriched enrollment. Using all trials, the three interventions were similar for consistently reported efficacy outcomes. Rates of successful intercourse for sildenafil, tadalafil and vardenafil were 65%, 62%, and 59%, with placebo rates of 23-28%. The rates of improved erections were 76%, 75% and 71%, respectively, with placebo rates of 22-24%, and NNTs of 1.9 or 2.0. Reporting of withdrawals was less consistent, but all-cause withdrawals for sildenafil, tadalafil and vardenafil were 8% 13% and 20%. All three drugs were well tolerated, with headache being the most commonly reported event at 13-17%. There were few serious adverse events.

CONCLUSION

There were differences between trials in outcomes reported, limiting comparisons, and the most useful outcomes were not reported. For common outcomes there was similar efficacy between PDE-5 inhibitors.

Erectile response to vardenafil in men with a history of nonresponse to sildenafil: A time-from-dosing descriptive analysis

BACKGROUND

The efficacy and tolerability of vardenafil hydrochloride in men with erectile dysfunction (ED) and a history of nonresponse to sildenafil citrate have previously been reported.

OBJECTIVE

The aim of this descriptive analysis was to assess the efficacy and tolerability of vardenafil at various times after dosing in men with ED and a history of nonresponse to sildenafil and who chose to attempt sexual intercourse between 0.25 and 6 hours after dosing with vardenafil.

METHODS

This analysis used data from a previously published 12-week, prospective, randomized, double-blind, flexible-dose, placebo-controlled study conducted at 41 hospitals and outpatient clinics across Australia, Europe, Asia, and North America. In that study, men with ED and sildenafil nonresponse, defined using 6 rigorous criteria (including nonresponse to the highest recommended dose, 100 mg/d) were assigned to receive vardenafil 10 mg or placebo QD. At study weeks 4 and 8, patients in both groups were given the option to maintain the 10-mg/d dose, or have the dose titrated to 5 or 20 mg/d. The present analysis used data from patient diaries completed daily, which included information concerning attempts at sexual intercourse, time from dosing to attempt, penetration, and maintenance of erection sufficient for successful intercourse. At week 12, diary data were categorized into time intervals (in hours) after dosing. For each interval, the per-patient success rate was based on the total number of attempts made in that interval. Comparative statistics were not performed on the time-interval analysis. Tolerability was monitored throughout the study. Data concerning the primary end point were reported previously.

RESULTS

A total of 463 men were enrolled, of whom 457 were included in the safety analysis (vardenafil, n = 231; placebo, n = 226) and 454 in the intent-to-treat analysis (vardenafil, n = 229; placebo, n = 225; mean age, 60.1 vs 59.0 years; mean body mass index, 28.7 vs 28.0 kg/m2). Six patients were excluded from the safety analysis (2 patients did not use study medication [placebo group], postbaseline safety data unavailable in 4 patients [2 in each study group]). Men receiving vardenafil had numerically greater penetration and completion success rates compared with those receiving placebo at all time intervals. Penetration success rates were numerically higher with vardenafil compared with placebo as early as within 0.25 hour after dosing (62% vs 30%); efficacy continued beyond 6 hours after dosing in 77% and 50% of patients, respectively. Similarly, vardenafil-treated patients had numerically greater completion success rates compared with those receiving placebo at 0.25 hour (53% vs 12%) and beyond 6 hours after dosing (70% vs 24%). The most common drug-related adverse events in the vardenafil and placebo groups were flushing (7% vs 1%), headache (6% vs 2%), and nasal congestion (5% vs <1%).

CONCLUSIONS

This descriptive analysis suggests that erection sufficient for penetration and intercourse completion was achieved within 0.25 hour and lasted for >6 hours after dosing with vardenafil 10 mg in these men with mostly moderate to severe ED and a history of nonresponse to sildenafil and who chose to make attempts during those intervals. The drug was generally well tolerated.

Vardenafil for the Treatment of Erectile Dysfunction: A Critical Review of the Literature Based on Personal Clinical Experience

OBJECTIVE

To critically review the literature on vardenafil in the treatment of erectile dysfunction while integrating the clinical findings with the personal experience of the authors.

METHODS

Analysis of published full-length papers that were identified through Medline search from January 2000 through May 2004. Abstracts published in peer-reviewed journals from the same period were also considered.

RESULTS

Efficacy, tolerability and safety, as reported in the peer-reviewed literature compares well with the authors' personal experience. Authors' personal observations include discussions on potency, selectivity, selection of initial dose, counselling for patients characteristically considered difficult-to-treat (diabetes, prostatectomy, depression), including the determination of the maximal efficacious dose and the possible role of daily dosing, optimisation of the use of vardenafil according to its pharmacokinetic and pharmacodynamic profiles (onset and reliability), and management of ED patients with or at risk for cardiovascular disease.

CONCLUSIONS

Extensive experience with vardenafil as reported in peer reviewed literature confirms the important role of vardenafil in the management of patients with ED. The development of each physician's own experience with vardenafil is key to optimise overall satisfaction of this therapy by the patient and his partner.