A dose-escalation study to assess the efficacy and safety of sildenafil citrate in men with erectile dysfunction

A real-world pharmacovigilance study of FDA adverse event reporting system events for sildenafil

BACKGROUND

Sildenafil, a selective inhibitor of phosphodiesterase type 5 (PDE5), is widely used for the treatment of erectile dysfunction (ED). However, the safety profile of sildenafil, including adverse event (AEs), requires comprehensive evaluation.

METHODS

This retrospective pharmacovigilance study aimed to evaluate AEs linked to sildenafil by analyzing data sourced from the FDA Adverse Event Reporting System (FAERS) database. A case/non-case design was utilized, and various algorithms including the reporting odds ratio (ROR), the proportional reporting ratio (PRR), the Bayesian confidence propagation neural network (BCPNN), and the multiitem gamma Poisson shrinker (MGPS) were employed to measure the signals indicating the presence of sildenafil-related AEs.

RESULTS

Among 339,230 reports, 33,692 specifically mentioned sildenafil use. Most of AEs occurred in males over 60 years old. The United States accounted for the highest proportion of reported AEs. Severe outcomes, including death, disability, and life-threatening events, were reported. Significant system organ class (SOC) included "Reproductive system and breast disorders" (SOC: 10038604), "Neoplasms benign, malignant and unspecified" (SOC: 10038738), "Vascular disorders" (SOC: 10047065), and "Blood and lymphatic system disorders" (SOC: 10005329). Noteworthy preferred terms (PTs) associated with sildenafil included "Vision blurred," "Flushing," "sudden hearing loss," "Painful erection," and "Priapism." Unexpected AEs, such as "Malignant melanoma," "Pulmonary hypertension," "Malignant melanoma in situ," "Pulmonary arterial hypertension," "Metastatic malignant melanoma," "Malignant melanoma stage III," "Malignant melanoma stage II," "Acquired hemophilia," "Aortic dissection rupture," and "Intracranial artery dissection" were also identified.

CONCLUSIONS

These findings emphasize the importance of monitoring and understanding the potential risks associated with sildenafil. Further investigation is warranted to validate these associations and address previously unrecognized safety concerns.

A randomized, controlled study of treatment with ojayeonjonghwan for patients with late onset hypogonadism

Objectives: We investigate the effects of Ojayeonjonghwan (KH-204) in men with late-onset hypogonadism (LOH) symptoms.Material and methods: Initial PSA, testosterone, lipid profile and questionnaires about LOH-related symptoms were checked. After 8 weeks of the treatment (control or KH-204), questionnaires and serological tests were repeated to evaluate the efficacy of the agent. The changes of variables in each group and the difference between two groups were compared.Results: A total of 78 men were enrolled, and randomly assigned to the control group (n = 39) or KH-204 group (n = 39). Baseline characteristics of both group are comparable. AMS total score of control and KH-204 group were both improved at 8 weeks (p = .010, <.001), and there was a statistically significant difference between the two groups (favorable in KH-204 group, p = .006). At 8 weeks, total IIEF score of control and KH-204 group were both improved, and there was no statistically significant difference in the degree of improvement between the two groups (p = .303). There was no statistically significant difference of laboratory findings, in intra-group changes and inter-group comparisons.Conclusions: KH-204 was found to be effective in all LOH symptoms without changing of laboratory results. KH-204 may be safely used for treatment of male with LOH-related symptoms.

Placebo Responses Among Men With Erectile Dysfunction Enrolled in Phosphodiesterase 5 Inhibitor Trials: A Systematic Review and Meta-analysis

IMPORTANCE

Placebo responses in the treatment of erectile dysfunction (ED) are poorly described in the literature to date.

OBJECTIVE

To quantify the association of placebo with ED outcomes among men enrolled in placebo-controlled, phosphodiesterase 5 inhibitor (PDE5I) trials.

DATA SOURCES

For this systematic review and meta-analysis, a database search was conducted to identify double-blind, placebo-controlled studies using PDE5Is for the treatment of ED published from January 1, 1998, to December 31, 2018, within MEDLINE, Embase, Cochrane Library, and Web of Science. Only articles published in the English language were included.

STUDY SELECTION

Double-blind, placebo-controlled randomized clinical trials of PDE5Is for ED were included. Studies were excluded if they did not provide distribution measures for statistical analysis. Study selection review assessments were conducted by 2 independent investigators. A total of 2215 studies were identified from the database search, and after review, 63 studies that included 12 564 men were analyzed.

DATA EXTRACTION AND SYNTHESIS

Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines were followed in abstracting data and assessing validity. Data were extracted from published reports by 2 independent reviewers. Quality assessment was performed using the Jadad scale. Data were pooled using a random-effects model.

MAIN OUTCOMES AND MEASURES

The main outcome was improvement in the erectile function domain of the International Index of Erectile Function questionnaire in the placebo arm of the included studies. Effect size was reported as bias-corrected standardized mean difference (Hedges g). The hypothesis was formulated before data extraction.

RESULTS

A total of 63 studies that included 12 564 men (mean [SD] age, 55 [7] years; age range, 36-68 years) were included. Erectile function was significantly improved among participants in the placebo arm, with a small to moderate effect size (Hedges g [SE], 0.35 [0.03]; P < .001). Placebo effect size was larger among participants with ED associated with posttraumatic stress disorder (Hedges g [SE], 0.78 [0.32]; P = .02) compared with the overall analysis. No significant difference was found between placebo and PDE5Is for ED after prostate surgery or radiotherapy (Hedges g [SE], 0.30 [0.17]; P = .08).

CONCLUSIONS AND RELEVANCE

In this study, placebo was associated with improvement of ED, especially among men with ED-related posttraumatic stress disorder. No difference was found between placebo and PDE5I among men treated for ED after prostate surgery.

Toward a Scientific Nutritional Supplement Combination for Prostatism and Erectile Dysfunction I: From Known Pharmacology to Clinical Testing

Prostatism and erectile dysfunction (ED) are highly prevalent and closely comorbid. Prescription treatments are limitingly expensive but robust in mechanisms of action (MoA). Nutritional supplements (NS) are low-cost but inadequately supported by evidence. Do any NS use robust MoA? Could their efficacy be amplified via dosing, concentration of active principles, and/or use in combination? The goal is to develop an effective NS for prostatism and ED using the MoA of prescription treatments. Literature reviews were conducted on dietary supplements for prostatism or ED and MoA of relevant drugs. The most promising NS employing these MoA were chosen. A pilot study of a prototype combination was conducted. A protocol was created for an adequate dose-response trial to test the NS combination in men with ED and prostatism. The main measures were response rates, International Prostate Symptom Score, and International Index of Erectile Function. For drugs, the MoAs best proven for prostatism and ED were nitric oxide augmentation, mild androgen inhibition, and anti-inflammatory effects. The following NS best simulate these MoA and are best supported for efficacy; for prostatism: beta sitosterol; for ED: panax ginseng, arginine, and citrulline. Pilot clinical data provided support. A plan for a formal dose-response clinical trial was approved by a central institutional review board. NS using effective MoA might suffice for prostatism and ED. Pilot testing of a combination NS with the best-supported MoA supported further development. A dose-response trial should be conducted using adequate doses of L-citrulline, beta-sitosterol, ginseng, and vitamin D3.

The devil is in the details: an analysis of the subtleties between phosphodiesterase inhibitors for erectile dysfunction

Erectile dysfunction (ED) is a common sexual disorder with numerous etiologies involving multiple organ systems that leads to significant distress and decreased quality of life for the affected men. Fortunately, there are several modalities and interventions for treating ED. Oral medications, intra-urethral compounds, intracorporeal injections, vacuum-assist devices and surgically implanted prostheses are all part of the treatment algorithm. One of the first-lines and certainly the most widely used options for treating ED is the family of oral phosphodiesterase type 5 inhibitors (PDE5I). The introduction of these medications in the late 1990s revolutionized the field of sexual medicine. Currently there are no guidelines and minimal literature to help providers choose among drugs in this class. This review will address differences in efficacy and side effects between various members of the oral selective phosphodiesterase-5 inhibitor class of drugs.

Sildenafil: two decades of benefits or risks?

Sildenafil is a selective inhibitor of cyclic guanosine monophosphate (cGMP)-specific phosphodiesterase type 5 (PDE-5). A patent was registered for this drug in 1990, which expired in 2010. Since expiration, the drug has been marketed under various trade names or as generic drugs. Numerous clinical trials have been conducted addressing the effectiveness of the drug for erectile dysfunction (ED) and its safety regarding the presence or absence of specific comorbidities. After over 20 years in the market, we need to ask: has the scientific community reached a general consensus as to the overall efficacy and safety of the drug? Can we firmly state that the benefits of the drug outweigh its risks? This review suggests that sildenafil is an effective and easily manageable treatment for erectile dysfunction, both in the absence and in the presence of comorbidities. After two decades of the emergence of sildenafil as a drug of choice for the treatment of ED (and the numerous studies and clinical trials undertaken during this time span), it is now possible to state that the benefits of the drug do outweigh the risks, and represent an significant improvement in the quality of life in men with ED.

PDE5 inhibitors: considerations for preference and long-term adherence

INTRODUCTION

Erectile dysfunction (ED) is a highly prevalent condition affecting nearly one in five men worldwide. The advent of phosphodiesterase type 5 inhibitors (PDE5i) has revolutionised the ED treatment landscape and provided effective, minimally invasive therapies to restore male sexual function.

MATERIALS AND METHODS

A pubmed search was performed of all English language articles from 1996 to present reviewing PDE5i, including pharmacokinetics, efficacy profiles and comparisons, where available.

RESULTS

Currently available PDE5i in the United States include sildenafil, vardenafil, tadalafil and avanafil, each of which has unique side effect, pharmacokinetic and outcome profiles. Sildenafil is associated with increased rate of visual changes, vardenafil with QT prolongation and tadalafil with lower back pain. Avanafil and vardenafil orodispersible tablet rapidly achieve peak plasma concentration, which results in faster onset of action, whereas tadalafil exhibits the longest half-life. First time response to PDE5i is approximately 60-70%, with no significant differences in efficacy noted among therapies. The literature does not clearly demonstrate a preference for one drug. High-treatment success rates (89%) were reported when patients were prescribed all available PDE5i. Daily dosing with tadalafil is associated with improved erectile function (EF) over time. Finally, novel modes of patient-provider interaction, including internet-based education, communication and prescribing, may also improve long-term adherence.

CONCLUSIONS

PDE5i represent first line therapy for ED with excellent overall efficacy and satisfactory side effect profiles. Enhanced communciation, coupled with increased knowledge of drug characteristics, comparative treatment regimens and optimal prescribing patterns, offer compelling tools to improve long-term treatment success.

Randomized, double-blinded, placebo-controlled crossover trial of treating erectile dysfunction with sildenafil after radiotherapy and short-term androgen deprivation therapy: results of RTOG 0215

INTRODUCTION

Erectile dysfunction (ED) may be the most commonly observed adverse event (AE) associated with the combination of radiation therapy (RT) and androgen deprivation therapy (ADT). A significant number of men are trying phosphodiesterase type 5 inhibitors (PDE5s) such as sildenafil to treat ED, yet sildenafil studies to date shed little light on the response to ED after ADT.

AIM

The purpose of this trial was to evaluate sildenafil in the treatment of ED in prostate cancer patients previously treated with external beam RT and neoadjuvant and concurrent ADT.

METHODS

  In this randomized, double-blinded crossover trial, eligible patients received RT/ADT for intermediate risk prostate cancer and currently had ED as defined by the International Index of Erectile Function (IIEF). Patients were randomized to 12 weeks of sildenafil or placebo followed by 1 week of no treatment then 12 weeks of the alternative. Treatment differences were evaluated using a marginal model for binary crossover data.

MAIN OUTCOME MEASURES

The primary end point was improved erectile function, as measured by the IIEF.

RESULTS

The study accrued 115 patients and 61 (55%) completed all three IIEF assessments. Sildenafil effect was significant (P = 0.009) with a difference in probabilities of erectile response of 0.17 (95% confidence interval: 0.06, 0.29), and 0.21 (0.06, 0.38) for patients receiving ≤ 120 days of ADT. However, as few as 21% of patients had a treatment-specific response, only improving during sildenafil but not during the placebo phase.

CONCLUSIONS

This is the first controlled trial to suggest a positive sildenafil response for ED treatment in patients previously treated with RT/ADT, however, only a minority of patients responded to treatment. ADT duration may be associated with response and requires further study. The overall low response rate suggests the need for study of additional or preventative strategies for ED after RT/ADT for prostate cancer.

Couple satisfaction to different therapeutic modalities for organic erectile dysfunction

INTRODUCTION

Erectile dysfunction (ED) treatment studies do not measure treatment response and treatment satisfaction (both patient and partner satisfaction) where dissatisfaction reflects an aspirations/achievement gap.

AIM

To test the subjective implications of satisfaction to various therapeutic modalities for pure or mixed organic ED, and to address changes in the health-oriented quality of life (QoL) and the relation of psychiatric status of these patients to treatment satisfaction.

METHODS

A prospective study included of 354 couples classified according to their line of therapy into five treated groups: testosterone, sildenafil citrate, intracavernosal injection, external negative vacuum device, and penile prosthesis.

MAIN OUTCOME MEASURES

Erectile Dysfunction Inventory of Treatment Satisfaction (EDITS) and the International Index of Erectile Function (IIEF). Satisfied patients were compared to unsatisfied cases using the PCASEE scale for QoL and Middlesex Hospital Questionnaire (MHQ) for psychiatric status.

RESULTS

Sildenafil citrate-treated group represented the highest mean value of satisfaction score on EDITS, erectile function, orgasmic function, and overall satisfaction domains of IIEF. Penile implants-treated group was the second for satisfaction score on EDITS. The testosterone-treated group represented the highest mean value for sexual desire domain score of IIEF. Low scores in various domains of QoL were significantly improved among satisfied cases more than unsatisfied subjects after therapy. High association was found between dissatisfaction and scores for anxiety, obsession, and phobia, followed by scores of depression and somatic concomitant of anxiety.

CONCLUSION

ED is best conceived as intermingle of somatic, lifestyle, psychological, and partner relationship determinants. This should be taken into account to increase sexual satisfaction with improved QoL, and not only to produce rigid erection.

[Erectile dysfunction and renal chronic insufficiency: etiology and management]

Erectile dysfunction (ED) has a higher incidence in patients treated for chronic renal insufficiency or in patients who underwent kidney transplanation as it concerns more than 50% of them. Its severity is directly linked with the seriousness of the renal disease. ED is responsible of a deterioration of the quality of life. ED's physiopathology is complex and multifactorial, involving a combination of classical risk factors (endothelial dysfunction), specific factors (e.g., chronic hyperuremia and co-morbidities) and psychological factors. Management of ED must take into account both sides of the disease in order to propose appropriate treatment; i.e, psychological concerns and organic matters. Although literature remains poor in this area, phosphodiesterase-5 inhibitors are increasingly used for these patients as they are safe and efficient most of the time. Pharmacokinetics of phosphodiesterase-5 inhibitors can be disturbed by the simultaneous use of immunosuppressor. As a second line, intra-cavernous injections remain a gold-standard treatment. In case of failure, penile prosthesis can even be considered in case of renal chronic insufficiency and in transplanted patients.

Interventions for sexual dysfunction following treatments for cancer

BACKGROUND

The proportion of people living with and surviving cancer is growing. This has led to increased awareness of the importance of quality of life including sexual function in people with cancer. Sexual dysfunction (SD) is a potential long-term complication of cancer treatments.

OBJECTIVES

Evaluate effectiveness of interventions for SD following treatments for cancer and their adverse effects.

SEARCH STRATEGY

The Cochrane Pain, Palliative & Supportive Care Register, Cochrane Central Register of Controlled Trials, MEDLINE, EMBASE, PsycInfo, AMED, CINAHL, Dissertation Abstracts and NHS Research Register were searched.

SELECTION CRITERIA

Randomised controlled trials (RCTs) were included that assessed the effectiveness of a treatment for SD. The trial population comprised of adults of either sex who at trial entry had developed SD as a consequence of cancer treatment.

DATA COLLECTION AND ANALYSIS

Two review authors independently extracted the data and assessed trial quality. Meta-analysis was considered for trials with comparable key characteristics.

MAIN RESULTS

Eleven RCTs with a total of 1743 participants were identified. The quality of the trials was poor. Ten trials explored interventions for SD in men following treatments for non-metastatic prostate cancer. One trial explored effectiveness in women of a lubricating vaginal cream following radiotherapy for cervical cancer. The strongest evidence (from four trials) was on oral phosphodiesterase type 5 (PDE5) inhibitors for erectile dysfunction (ED) following radiotherapy of the prostate or radical prostatectomy. The results using validated measures in all trials significantly favoured those in the PDE5 inhibitor group(s). The combined results of two trials indicated a significantly greater improvement in ED in the PDE5 inhibitor groups (odds ratio (OR) 10.09 95% confidence interval (CI) 6.20 to 16.43). Negative effects were few and usually mild to moderate headaches or flushing. One trial reported more clinically serious events including six events of tachycardia and six of chest pain. Following prostate cancer treatments there was some evidence that PDE5 inhibitors are more effective in combination with acetyl-L-carnitine and propionyl-L-carnitine and that sexual counselling improves self-administration of prostaglandin intra-cavernous injection for SD. There was some evidence following treatment for prostate cancer that transurethral alprostadil and vacuum constriction devices reduce SD, although in both trials negative effects were fairly common. There is some evidence that vaginal lubricating creams reduce SD.

AUTHORS' CONCLUSIONS

PDE5 inhibitors are an effective treatment for SD secondary to treatments for prostate cancer. Other interventions identified need to be tested in further RCTs. The SD interventions in this review are not representative of the range available for men and women. Further evaluations are needed for these interventions for SD following cancer treatments.

Analysis of the efficacy and safety of sildenafil citrate in the geriatric population

OBJECTIVE

To define the efficacy and tolerability of sildenafil in elderly men, as epidemiological data show an increasing life-expectancy of the population, and age is not only correlated with increasing morbidity but also an increase in the prevalence of erectile dysfunction (ED), for which sildenafil, available for >8 years, is effective and safe across a wide variety of medical comorbidities, severity and causes of ED.

PATIENTS AND METHODS

A database was generated from all sildenafil users in one sexual medicine practice, and data were extracted for men aged >60 years. The database included data on patient demographics, comorbidities, International Index of Erectile Function (IIEF) scores and adverse events (AEs). The patients were subdivided into those aged 60-69 (group 1), 70-79 (group 2), and > or = 80 years (group 3). Analysis of variance was used to assess differences among the three groups for several variables of demographics and erectile response.

RESULTS

In all, 167 patients were analysed; there were no significant differences in the duration of ED (5 +/- 3 years) or presence of comorbidities among the three groups. With a mean of two risk factors, the overall incidence of comorbidities was hypertension in 37%, dyslipidaemia in 28%, diabetes in 26%, coronary artery disease in 18% and lower urinary tract symptoms in 46%. The efficacy data showed that overall, 54% of men responded to sildenafil, with a mean increase in IIEF EF domain score of 5.7. Within the three groups there was a significant age-related decrease in response rate and IIEF EF domain score with age. However, there was no difference in AE incidence among the three groups, with an overall profile of 18% headache, 8% flushing, 8% dyspepsia, 5% nasal congestion and 2% visual changes. No overt cardiovascular events were reported.

CONCLUSIONS

From these data, sildenafil is an effective agent in elderly men, but had a lower efficacy rate with increasing age, especially in men aged >80 years. The incidence of side-effects was similar to that in the general population taking sildenafil, with no difference in AEs among the different age groups.

Correlations between increased erection hardness and improvements in emotional well-being and satisfaction outcomes in men treated with sildenafil citrate for erectile dysfunction

To explore relationships between erection hardness and other outcomes in men with erectile dysfunction (ED). Pooled analyses were conducted on 27 randomized, double-blind, placebo-controlled trials and six open-label trials from the worldwide sildenafil database. Outcomes included erection hardness graded subjectively, hardness and sexual satisfaction questions from the International Index of Erectile Function, general and sexually-specific emotional well-being from the self-esteem and relationship questionnaire, and the erectile dysfunction inventory of treatment satisfaction. Hardness outcomes improved (with a possible dose-response relationship for the achievement of fully hard and rigid erections) and correlated positively with the other outcomes. Sildenafil 100 mg produced optimal erection hardness (fully hard and rigid erections) in a substantial proportion of men with ED. Because optimal erection hardness correlated positively with some emotional well-being and satisfaction outcomes, sildenafil 100 mg may be the most appropriate dosage for treatment of ED for most men.

Efficacy and Safety of Tadalafil in Men with Erectile Dysfunction with a High Prevalence of Comorbid Conditions: Results from MOMENTUS: Multiple Observations in Men with Erectile Dysfunction in National Tadalafil Study in the US

INTRODUCTION

Limited efficacy and safety data exist from open-label clinical trials of phosphodiesterase 5 inhibitors in men with erectile dysfunction (ED) and multiple comorbid (MCM) conditions, historically a difficult group to treat.

AIM

A multicenter study (Multiple Observations in Men with Erectile Dysfunction in National Tadalafil Study in the US) assessed efficacy and safety of tadalafil in men with ED and MCM conditions.

MAIN OUTCOME MEASURES

The primary end point was change from baseline in the erectile function (EF) domain of the International Index of Erectile Function. Secondary end points included the Sexual Encounter Profile, Global Assessment Questions, and Sexual Self-Confidence and Spontaneity Domains of the Psychological and Interpersonal Relationship Scales.

METHODS

This was an open-label, multicenter study in men with ED. Tadalafil 20 mg was administered as needed prior to sexual activity, up to once/day, for 12 weeks following a 4-week ED-treatment-free period. The MCM group was 155 of 1,911 men enrolled in this study. Men in the MCM group met eligibility criteria but could not be included in other predefined groups: (i) Caucasian; (ii) Black American; (iii) Hispanic (groups 1-3, < or =65 years, no diabetes or depression); (iv) depression, < or =65 years, no diabetes; (v) diabetes, < or =65 years, no depression; (vi) >65 years, no diabetes or depression; and (vii) ED subsequent to traumatic spinal cord injury.

RESULTS

Mean baseline EF domain score in MCM (mean age 65 +/- 9 years) was 12.2 +/- 6.5; 52% of subjects had severe ED; 72% diabetes mellitus; 67% cardiovascular disease (including hypertension); 49% hyperlipidemia; 38% depression; 84% had two or more comorbidities. At end point, there was a significant (P < 0.001) mean change of 7.6 from baseline in mean EF domain score. Among men with severe ED, 22% achieved an EF domain score > or =26. Most common adverse events were headache 5.2%; flushing 3.9% and nasal congestion 3.2%; 3% discontinued use because of an adverse event.

CONCLUSIONS

In this open-label clinical trial of older men with ED and MCMs, tadalafil 20 mg significantly increased all efficacy end points and was well-tolerated.

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.

ORIGINAL RESEARCH—ED PHARMACOTHERAPY: Comparing Vardenafil and Sildenafil in the Treatment of Men with Erectile Dysfunction and Risk Factors for Cardiovascular Disease: A Randomized, Double‐Blind, Pooled Crossover Study

INTRODUCTION

Data from head-to-head clinical trials of phosphodiesterase type 5 (PDE5) inhibitors are scarce, making it difficult for clinicians to differentiate among these agents to select the most appropriate treatment for their patients with erectile dysfunction (ED).

AIM

This randomized, double-blind, crossover head-to-head clinical trial compared patient preference, efficacy, and safety of vardenafil and sildenafil in men with ED and diabetes, hypertension, and/or hyperlipidemia.

METHODS

Prospective analysis was performed on two studies in which 1,057 men were randomized to vardenafil 20 mg (N = 530) or sildenafil 100 mg (2 x 50 mg encapsulated tablets) (N = 527) for 4 weeks. Following a 1-week washout, patients switched treatment for 4 weeks.

MAIN OUTCOME MEASURES

Patients were asked about overall preference: "Overall, which medication do you prefer?", plus 11 other preference questions relating to their ED treatment. Efficacy assessments after each treatment period included the erectile function (EF) domain score of the International Index of Erectile Function (IIEF); Sexual Encounter Profile (SEP) diary questions SEP2 and SEP3; Global Assessment Question (GAQ); and Treatment Satisfaction Scale (TSS). Data regarding adverse events were collected throughout the study.

RESULTS

A total of 931 men (mean age 57.9 years) were included in the intent-to-treat (ITT) population. Non-inferiority of vardenafil over sildenafil was achieved for overall preference (vardenafil 38.9%; sildenafil 34.5%; and no preference 26.6%). Additionally, the change from baseline in the EF domain score of the IIEF achieved nominal significance for vardenafil over sildenafil (10.00 vs. 9.40; P = 0.0052). Patients also had a higher percentage of positive responses for vardenafil for SEP2, SEP3, GAQ, and 12 of 19 questions on the TSS. Both drugs were well tolerated.

CONCLUSIONS

This randomized, double-blind, head-to-head trial in ED patients with cardiovascular risk factors demonstrated noninferiority of vardenafil for overall preference. Vardenafil achieved nominal statistical superiority over sildenafil for several frequently used efficacy measures. Both drugs were well tolerated.

Erectile function and assessments of erection hardness correlate positively with measures of emotional well-being, sexual satisfaction, and treatment satisfaction in men with erectile dysfunction treated with sildenafil citrate (Viagra)

We aimed to determine whether erectile function (EF) and assessments of erection hardness correlate positively with measures of psychosocial outcomes (ie, emotional well-being, sexual satisfaction, and satisfaction with erectile dysfunction [ED] treatment) in men treated with sildenafil citrate (Viagra; Pfizer Inc, New York, NY). Data were collected from 33 worldwide phase 2, 3, and 4 sildenafil clinical trials, which included almost 10,000 men with ED. Most of these trials were randomized, double-blind, and placebo-controlled (n = 27) and were undertaken to assess doses of 50 mg adjustable to 25 mg or 100 mg, depending on efficacy and tolerability (n = 32). Doses were taken approximately 1 hour before anticipated sexual activity but not more often than once daily. EF was assessed with use of the EF domain of the International Index of Erectile Function (IIEF) and with assessments of erection hardness (Erection Hardness Grading Scale [EHGS] and IIEF Q2 [the frequency of erections hard enough for penetration]). Change (baseline to end point) in emotional well-being in men treated for ED was assessed with the Self-Esteem and Relationship (SEAR) questionnaire, which consisted of the Confidence domain (ie, the Self-Esteem subscale and Overall Relationship subscale) and the Sexual Relationship domain. End point treatment satisfaction (overall, speed of onset, and duration of action) was assessed with the Erectile Dysfunction Inventory of Treatment Satisfaction (EDITS). The IIEF was used to assess change and end point sexual satisfaction by means of the Intercourse Satisfaction domain, Q7 (frequency of satisfactory sexual intercourse), and the Overall Satisfaction domain (ie, Q13, satisfaction with sex life, and Q14, satisfaction with sexual relationship). In men treated with sildenafil for ED, scores for measures of EF (IIEF EF domain, IIEF Q2) and the percentage of erections graded completely hard and fully rigid (EHGS grade 4) correlated positively with scores for measures of psychosocial outcomes (SEAR emotional well-being, IIEF sexual satisfaction, and EDITS ED treatment satisfaction), indicating that when EF improved and erection hardness increased, these measures of psychosocial function also improved.

Research instruments for the diagnosis and treatment of patients with erectile dysfunction

As the incidence and prevalence of erectile dysfunction (ED) increase, healthcare providers will require robust, accurate, and efficient tools for appropriately diagnosing and treating patients with ED. Moreover, clinicians will need effective follow-up tools that assess treatment efficacy and satisfaction, to help patients meet their expectations for successful treatment of ED. We provide a summary of some of the most commonly used instruments for the diagnosis and assessment of ED treatment efficacy that will be referred to in this supplement.

A meta-regression analysis of treatment effect modifiers in trials with flexible-dose oral sildenafil for erectile dysfunction in broad-spectrum populations

Several trials and reviews provide evidence for the efficacy of phosphodiesterase-5 inhibitors in the treatment of erectile dysfunction (ED). However, little is known about the impact of treatment effect modifiers other than concomitant diseases. Our objective was to identify patient and trial characteristics as well as methodological and publication-related issues that are associated with the treatment effect measured in flexible-dose randomized controlled trials of oral sildenafil for ED. The MEDLINE and the Cochrane Central databases were searched for efficacy trials of sildenafil. Thirteen trials fulfilled all inclusion criteria. A series of meta-regression and graphical analyses were performed to test the impact of possible effect modifiers. Treatment effect was influenced by mean baseline disease severity and mean duration of the disease. These associations were at least partly mediated by placebo response. Trial duration, age of patients and etiology of ED in patients did not have any significant influence on the treatment effect. The year of publication of primary trials was also related to trial findings. Our analysis adds important data to enable the control of confounding variables in future trials and meta-analyses. It might also help the individual to assess the unbiased efficacy and true innovative potential of available and forthcoming pharmacological agents.

Drug Insight: oral phosphodiesterase type 5 inhibitors for erectile dysfunction

Erectile dysfunction (ED) is a common medical condition that affects the sexual life of millions of men. At present, first-line oral pharmacotherapy for most patients with ED is a phosphodiesterase type 5 (PDE-5) inhibitor, of which three are currently available worldwide. Sildenafil (Viagra, Pfizer) has a very satisfactory efficacy-safety profile in all patient categories. The first PDE-5 inhibitor to reach the market, it is now the most widely prescribed oral agent for ED. Tadalafil (Cialis, Lilly ICOS) and vardenafil (Levitra, Bayer/GlaxoSmithKline) were introduced to the European Union and the US in 2003 and 2004, respectively. These three PDE-5 inhibitors share many characteristics, but each has unique features. This review describes the chemical, pharmacologic and clinical features of sildenafil, vardenafil and tadalafil as oral first-line treatments for ED. First, we describe the physiology of penile erection and PDE-5 inhibitor pharmacology, including chemistry, PDE selectivity, pharmacokinetics, and possible drug interactions. We then summarize data on the efficacy and safety profiles of the three PDE-5 inhibitors for the treatment of ED in the general population, in patients with diabetes mellitus and in men that have undergone bilateral nerve-sparing retropubic radical prostatectomy.

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.

Clinical and Duplex US Assessment of Effects of Sildenafil on Cavernosal Arteries of the Penis: Comparison with Intracavernosal Injection of Vasoactive Agents—Initial Experience

PURPOSE

To prospectively evaluate the clinical response and hemodynamic changes in cavernosal arteries after oral administration of sildenafil without and with audiovisual sexual stimulation and to compare those responses with responses from intracavernosal injections of vasoactive agents.

MATERIALS AND METHODS

Institutional review board approval and written informed consent were obtained. Thirteen consecutive patients (age range, 22-77 years; mean, 60.4 years) with erectile dysfunction were evaluated with clinical assessment and cavernosal duplex ultrasonography (US). The patients were examined at two sessions 3 weeks apart. First, each patient received 100 mg of sildenafil citrate orally and was examined 60 minutes later without any sexual stimulation. Each patient then underwent repeat clinical and duplex US assessment after audiovisual sexual stimulation. Three weeks later, the patients underwent identical clinical evaluation and duplex US after intracavernosal injection of a commercially available combination of papaverine, prostaglandin E1, and phentolamine. Clinical and duplex US data (ie, peak systolic velocity [PSV]) were examined by using the Wilcoxon signed rank test for matched pairs.

RESULTS

At rest, the overall mean cavernosal artery PSV was 1.08 cm/sec and remained unchanged after intake of sildenafil without any audiovisual stimulation, with no clinical evidence of erection. With the addition of audiovisual sexual stimulation, eight (62%) of 13 patients had penile congestion or erection, and six (46%) had a PSV greater than 25 cm/sec. With intracavernosal injection of the combination of three drugs, all 13 patients achieved congestion or erection, and 10 (77%) had a PSV greater than 25 cm/sec. Both clinical and duplex US responses to intracavernosal injection were significantly greater than they were to sildenafil with audiovisual sexual stimulation (P = .04 and .003, respectively).

CONCLUSION

Oral sildenafil with audiovisual sexual stimulation led to a significant clinical response and increment in blood flow in the cavernosal arteries. However, more patients responded to intracavernosal injection of the combination of three drugs than to sildenafil, and the clinical response was significantly better.

Clinical update on phosphodiesterase type-5 inhibitors for erectile dysfunction

Erectile dysfunction (ED) affects the sexual lives of millions of men. The first-line oral pharmacotherapy for most ED patients is phosphodiesterase type-5 (PDE-5) inhibitors, of which three are available. Sildenafil is the most widely prescribed oral agent for ED and has a very satisfactory efficacy-safety profile in all patient categories. Tadalafil and vardenafil were introduced in the European Union and in the United States in 2003 and 2004, respectively. The three PDE-5 inhibitors share many pharmacological and clinical characteristics, and each has unique features. This review, which is based on the contemporary literature on PDE-5 inhibitors, describes the chemical, pharmacological, and clinical features of sildenafil, vardenafil, and tadalafil. The first section reviews the pathophysiology of penile erection and PDE-5 inhibitor pharmacology. The second section summarizes data regarding efficacy and safety of the three drugs in treating ED in the general population as well as in selected patient categories.

The efficacy of tadalafil in improving sexual satisfaction and overall satisfaction in men with mild, moderate, and severe erectile dysfunction: a retrospective pooled analysis of data from randomized, placebo-controlled clinical trials

BACKGROUND

Satisfaction with the sexual experience is considered important when evaluating the impact of treatments for erectile dysfunction (ED), yet satisfaction has been infrequently assessed in clinical trials.

OBJECTIVE

To evaluate satisfaction with, and enjoyment of, the sexual experience in men with ED enrolled in 11 placebo-controlled clinical trials of tadalafil.

STUDY DESIGN AND METHODS

Retrospective pooled analysis of data from 11 randomized, double blind, placebo-controlled clinical trials of tadalafil. Men with mild (N = 838), moderate (N = 558), or severe (N = 703) ED who were randomized to tadalafil 10 mg or 20 mg or placebo taken as needed for 12 weeks were included in this analysis. Efficacy measures included the International Index of Erectile Function (IIEF). Reported herein are the scores on the IIEF overall satisfaction domain and individual IIEF questions (IIEF-Q7, satisfaction with intercourse; and IIEF-Q8, enjoyment of intercourse).

RESULTS

At least moderate satisfaction (IIEF overall satisfaction domain) was reported by 55% and 72% of patients with mild ED taking tadalafil 10 mg and 20 mg, respectively, compared with 33% taking placebo (p < 0.002); 60% and 65% vs. 19% of patients with moderate ED (p < 0.001); and 32% and 49% vs. 9% with severe ED (p < 0.001). Satisfactory intercourse during most attempts or almost always/always (IIEF-Q7) was reported by 59% and 79% of patients with mild ED taking tadalafil 10 mg and 20 mg vs. 32% taking placebo (p < 0.001); 52% and 65% vs. 18% with moderate ED (p < 0.001); and 28% and 49% vs. 5% with severe ED (p < 0.001). Highly or very highly enjoyable intercourse (IIEF-Q8) was reported by 45% and 63% of patients with mild ED taking tadalafil 10 mg and 20 mg vs. 21% taking placebo (p < 0.001); 43% and 56% vs. 16% with moderate ED (p < 0.001); and 19% and 44% vs. 5% with severe ED (p < 0.001).

CONCLUSIONS

Compared with placebo, tadalafil 10 mg and 20 mg improved overall satisfaction with the sexual experience, intercourse satisfaction, and intercourse enjoyment in men with mild, moderate, and severe ED.

Comparison of clinical trials with sildenafil, vardenafil and tadalafil in erectile dysfunction

Erectile dysfunction (ED) affects up to 50% of men, between 40 and 70 years of age. In the first major trial of sildenafil in ED, at 24 weeks, improved erections were reported by 77 and 84% of men taking sildenafil 50 and 100mg, respectively. Subsequently, sildenafil has been reported to be effective in men with ED associated with diabetes and prostate cancer, and in psychogenic ED. Sildenafil is safe in men with coronary artery disease, provided it is not used with the nitrates (a contraindication). The most commonly reported adverse effects with sildenafil are headache, flushing and dyspepsia. Vardenafil is more potent and more selective than sildenafil at inhibiting phosphodiesterase-5. Vardenafil is similarly effective to sildenafil in the treatment of ED. The only advantage that vardenafil has over sildenafil is that it does not inhibit phosphodiesterase-6 to alter colour perception, a rare side effect which sometimes occurs with sildenafil. Tadalafil has a longer duration of action than sildenafil and vardenafil. Tadalafil is similarly effective as sildenafil in the treatment of ED. In comparison studies, tadalafil is preferred to sildenafil (50/100mg) by men with ED, possibly because of its longer duration of action. Of the phosphodiesterase inhibitors, tadalafil may displace sildenafil as the drug of choice among men with ED.

Long‐Term Effect of Inhibition of the Angiotensin‐Converting Enzyme (ACE) on Cavernosal Perfusion in Men with Atherosclerotic Erectile Dysfunction: A Pilot Study

INTRODUCTION

Impaired perfusion of the corpora cavernosa is considered an important causal factor of erectile dysfunction (ED) in the aging male with atherosclerosis. Aim. On the basis of this notion, we hypothesized that inhibition of angiotensin-converting enzyme (ACE) may have a structural beneficial effect on cavernosal perfusion and subsequently on erectile function in men with impaired cavernosal perfusion.

METHODS

A total of 59 men with atherosclerotic ED (mean age, 60.0 +/- 6.8 years) and impaired cavernosal perfusion, as demonstrated with penile-pharmaco duplex ultrasonography, were randomized between an ACE inhibitor and placebo treatment arm. The minimum period of intervention was 26 weeks (26-46 weeks). The goal of the study was to demonstrate an improvement of (i) cavernosal arterial perfusion demonstrated by a decrease of blood flow velocity waveform; and (ii) erectile function in the erection domain of the International Index of Erectile Function.

RESULTS

Cavernosal perfusion improved significantly (paired samples t-test, P < 0.05) in both study arms, but the improvement did not differ significantly (anova, P > 0.05) between both arms. The number of sexually active men increased, and the severity of ED decreased in both groups.

CONCLUSION

Although a persisting improvement of cavernosal perfusion by at least a 6 month-administration of an ACE inhibitor in men with advanced atherosclerotic ED could not be demonstrated in this pilot study, the beneficial effect on cavernosal perfusion, sexual activity, and erectile function in all participants of this study is remarkable. This pilot study warrants a follow-up study in sexually more active men with ED and less advanced atherosclerosis to show that ACE inhibition may result in persisting improvement of cavernosal perfusion.

Prevention and treatment of erectile dysfunction using lifestyle changes and dietary supplements: what works and what is worthless, part I

Clinicians working in urology should adhere to the same guidelines that are observed in cardiovascular medicine when dealing with a patient with ED. A golden opportunity exists to discuss lifestyle changes with any man with or concerned about ED. Providing heart-healthy recommendations to men with minimal to extensive ED may produce a twofold impact: (1) patients may be able to affect the future extent of their disease, and (2) patients may become healthier overall. Patients following a heart-healthy lifestyle after a diagnosis of ED or to prevent ED should enjoy increased quality or quantity of life. The time is more than ripe for patients to understand that heart health is tantamount to erectile health.

Cross-cultural adaptation and validation of the English version of the International Index of Erectile Function (IIEF) for use in Malaysia

We adapted the English International Index of Erectile Function (IIEF) into Malay. This was difficult as many sex-related terms do not exist in colloquial Malay. In the pretest, there was no difficulty with comprehension and all subjects judged the Malay IIEF equivalent to the English IIEF. After slight modification, a final instrument was evaluated in two studies. Study A included 136 subjects. It showed that the instrument had good reliability and discriminant validity. The factor structure of the English IIEF was not reproducible. Study B included 26 ED subjects who underwent oral sildenafil therapy. The Malay IIEF was sensitive to treatment response. The area under the ROC curve of the Malay IIEF-5 was 0.86; the optimal cutoff score has a sensitivity of 85% and specificity of 75%. The results suggest that the Malay IIEF requires more work, but the Malay IIEF-5 has acceptable measurement properties to recommend its use in clinical practice and research.

A baseline-controlled, open-label, flexible dose-escalation study to assess the safety and efficacy of sildenafil citrate (Viagra) in patients with erectile dysfunction

Although sildenafil citrate (Viagra) has demonstrated effectiveness in the treatment of erectile dysfunction (ED), the dosing regimens often used in clinical trials may not always match those employed in clinical practice. This study was undertaken to further assess the efficacy and safety of sildenafil taken as required in male outpatients 18 years of age and older with ED (n=71). It was conducted as a placebo-baseline-controlled, open-label, flexible dose-escalation study, with sildenafil (25,50, or 100 mg) administered for 8 weeks following a 4-week placebo run-in. Efficacy variables included questions 3 and 4 of the International Index of Erectile Function (IIEF), other IIEF domains, patient event logs, and quality-of-life (QOL) assessments. Treatment with sildenafil resulted in improvements from baseline in all IIEF domains analyzed (all P<0.0001), as well as overall QOL and amelioration of specific sexual and social relationships (all P&<0.0001). Sildenafil was well tolerated. One participant discontinued treatment because of adverse events. Results suggest that flexible dosing with oral sildenafil is safe and has beneficial effects on all indices of erectile function and QOL.

Sildenafil in erectile dysfunction: a critical review

Sildenafil citrate (Viagra) is a potent orally active cGMP-specific phosphodiesterase type 5 (PDE5) inhibitor that is effective as a peripheral conditioner in the treatment of male erectile dysfunction (ED) of organic, psychogenic or mixed aetiology. Sildenafil is the first effective oral agent in the management of ED that has had a revolutionary impact on management of ED. The present review has been subdivided into five major sections. Based on the most recent peer-reviewed publications, the first section is aimed at critically evaluating PDE5 selectivity as well as the pharmacokinetics and pharmacodynamics of the drug, mainly to assess the best doses for each group of patients (i.e. adult and elderly men). Effectiveness in a broad spectrum ED population is the subject of the second section of the review, principally reporting post-marketing company-independent results. Safety and tolerability are the key concerns of the third section, with a broad consideration of the most commonly reported adverse events. Special attention has been paid to the cardiovascular safety of the drug, chiefly outlining the positive and potentially protective cardiac effects of sildenafil. Moreover, the impact of sildenafil in special patient populations is considered, namely in men complaining of diabetes mellitus, depression, neurological disorders, renal failure and those who have undergone a radical prostatectomy. Sildenafil and the ageing male has been especially underlined. Finally, the review covers a few new potential applications of sildenafil in ED patients with regard to high-dose treatment and combination therapy. The review ends with several considerations regarding the direct and/or indirect impact of sildenafil over quality of life and quality of partnership.

Current oral treatments for erectile dysfunction

Erectile dysfunction (ED) is defined as the inability to achieve and maintain a penile erection adequate for satisfactory sexual intercourse. It is a significant male health problem of global dimensions affecting approximately 150 million men worldwide. A broad range of options are currently available for the management of ED. They include oral agents (phosphodiesterase 5 inhibitors, dopamine agonists and alpha-receptor blocking drugs), intracavernosal injection (papaverine, phentolamine, prostaglandin E1, vasoactive intestinal peptide), transurethral vasoactive agents (prostaglandin E1), vacuum erection devices, vascular surgery and penile prostheses. Here we review the physiology of penile erection and the currently available oral preparations. In addition, novel therapeutic strategies to improve erectile function are discussed.

The International Index of Erectile Function (IIEF): a state-of-the-science review

The International Index of Erectile Function (IIEF) is a widely used, multi-dimensional self-report instrument for the evaluation of male sexual function. It is has been recommended as a primary endpoint for clinical trials of erectile dysfunction (ED) and for diagnostic evaluation of ED severity. The IIEF was developed in conjunction with the clinical trial program for sildenafil, and has since been adopted as the 'gold standard' measure for efficacy assessment in clinical trials of ED. It has been linguistically validated in 32 languages and used as a primary endpoint in more than 50 clinical trials. This review summarizes early stages in the psychometric validation of the instrument, its subsequent adoption in randomized clinical trials with sildenafil and other ED therapies, and its use in classifying ED severity and prevalence. The IIEF meets psychometric criteria for test reliability and validity, has a high degree of sensitivity and specificity, and correlates well with other measures of treatment outcome. It has demonstrated consistent and robust treatment responsiveness in studies in USA, Europe and Asia, as well as in a wide range of etiological subgroups. Although only one direct comparator trial has been performed to date, the IIEF is also sensitive to therapeutic effects with treatment agents other than sildenafil. A severity classification for ED has recently been developed, in addition to a brief screening version of the instrument. This review includes the strengths as well as limitations of the IIEF, along with some potential areas for future research.

Clinical efficacy and safety of sildenafil citrate (Viagra) in a multi-racial population in Singapore: A retrospective study of 1520 patients

BACKGROUND

Sildenafil citrate (Viagra), a selective inhibitor of cGMP-specific phosphodiesterase type-5, has been used as an oral therapeutic drug for erectile dysfunction. The present paper is a clinical study of the success rate and side-effects of the use of sildenafil in a multi-racial population in Singapore.

METHODS

From April 1999 to May 2000, 1520 patients were given sildenafil citrate. Of these, 912 patients (mean age, 54.6 years; age range, 22-99 years) were followed up and evaluated for clinical efficacy and safety of the drug. The mean duration of erectile dysfunction (ED) and follow-up periods were 31.5 and 3.0 months, respectively.

RESULTS

Satisfactory erections assessed by single global efficacy question (GEQ) occurred in 83% of patients, major side-effects in the form of flushing (3.48%), headache (1.97%), blurred vision (1.25%), giddiness (1.18%), warmth (1.11%) and others (4.92%) were recorded in 127 patients (13.9%). Racially, Chinese men with ED had higher efficacy (85.7%), compared to Indian men (74.2%) and Malay men (72.8%). With respect to comorbid profiles, an efficacy of 77.8% (n = 271), 83.9% (n = 292), 86.4% (n = 44) and 83.3% (n = 199) was recorded in diabetic, hypertensive, ischemic heart disease patients and in benign prostatic hyperplasia patients, respectively. Patients who smoked (n = 135) and drank alcohol (n = 118) showed an efficacy of 80%. Baseline hormonal profiles of luteinizing hormone, follicle stimulating hormone, testosterone and prolactin did not affect the success rates of sildenafil citrate. Many patients had earlier received other forms of treatment (medicated urethral suppository for erection (MUSE; 84.9%); vacuum devices (86.8%), traditional medicines (100%) and other oral medications (89.2%)), but this did not influence the success rate of sildenafil citrate. But patients previously treated with prostaglandin-E intracavernosal injections were less successful on sildenafil citrate (77.3%). In the total cohort, 50 mg sildenafil citrate was an effective dose in 49% of patients and 46.5% patients needed 100 mg sildenafil citrate, while 4.1% of the total cohort needed only 25 mg sildenafil citrate.

CONCLUSION

Oral sildenafil citrate has been shown to be an effective, safe and well tolerated drug in Singaporean men with ED, as in men from other parts of the world.

Effects of sildenafil citrate (viagra) on blood pressure in normotensive and hypertensive men

OBJECTIVES

To determine the occurrence of clinically significant decreases in blood pressure (BP) with sildenafil use in normotensive and hypertensive men by means of ambulatory BP monitoring.

METHODS

On 2 nights, 49 men (22 hypertensive, 27 normotensive) had their ambulatory systolic BP (SBP), diastolic BP (DBP), and heart rate monitored during the first 3 hours (waking period) and every 30 minutes after midnight for 3 additional hours (sleeping period). No medication was taken on one night; sildenafil 100 mg was taken on the other.

RESULTS

Sildenafil decreased SBP (-6.0 mm Hg; P = 0.0003), DBP (-4.5 mm Hg; P = 0.001), and mean arterial pressure (-5.3 mm Hg; P = 0.00008). The BP-lowering effects of sildenafil did not differ significantly in the normotensive and hypertensive men. Age significantly affected the BP reductions; decreases in SBP, DBP, and mean arterial pressure were greater in men 49 years old and older than in those younger than 49 years old. According to readings averaged over the entire control and treatment periods, 22.7% of hypertensive men and 3.7% of normotensive men experienced SBP reductions of 20 mm Hg or greater (P = 0.08 for comparison of the two groups); the respective values for DBP were 9.1% and 3.7% (P not significant). These reductions were not associated with any hypotensive symptoms. All participants tolerated sildenafil well.

CONCLUSIONS

Sildenafil caused small, clinically insignificant reductions in ambulatory BP in active and resting normotensive and hypertensive men. The results of this study suggest that, when used in accordance with the prescribing information and current treatment guidelines, sildenafil should be safe in younger and older men with or without hypertension.

The clinical safety of viagra

Erectile dysfunction (ED) in men is amenable to correction with Viagra in a majority of patients. The accumulated experience of prescribing Viagra across the broad continuum of men suffering from ED is sufficient for a meaningful assessment of the safety of Viagra in clinical practice. The use of Viagra necessitates caution in cardiac failure and when used within six months of acute myocardial infarction and stroke. It is inadvisable in patients with unstable angina pectoris. The co-administration of Viagra with organic nitrates, for example, glyceryl trinitrate or isosorbide dinitrate, is unsafe. The relative contraindications to Viagra in cardiovascular disease are uncontrolled hypertension and impaired cardiac reserve. With respect to interactions with other drugs, the potential influence on the metabolism of Viagra by medications that affect the cytochrome-P-450 system does not translate into clinical effects. The vasodilatory properties of sildenafil citrate are largely responsible for unwanted effects. The most common side effects are headache, flushing (due to vasodilation), and dyspepsia (due to relaxation of the smooth muscle of the gastroesophageal sphincter with reflux). In the recommended single-dose range (25-100 mg), the use of Viagra for erectile dysfunction, in the absence of contraindications, is extremely safe provided the drug is taken under proper conditions.

Intracavernous injections for erectile dysfunction in patients with cardiovascular diseases and failure or contraindications for sildenafil citrate

The aim of this study was to evaluate the effectiveness of a progressive program for the treatment of erectile dysfunction in patients with cardiovascular disease in whom sildenafil citrate (Viagra) was not an option. The study population included 106 patients selected from 267 with cardiovascular disease. The intracavernous injection program consisted of three protocols of increasingly complex combinations of vasoactive drugs, papaverine, phentolamine, prostaglandin E1 and atropine sulfate. Patients who failed the first protocol were switched to the second, and those who failed the second were switched to the third. A positive response was defined as an erection sufficient for vaginal penetration. A positive response was achieved on protocol I in 61 of the 106 patients (57.5%); protocol II in 32 of the remaining 45 patients (71.1%); and protocol III in seven of the remaining 13 patients (53.8%); the total success rate was 94.3%. These 100 patients were included in the 1-year follow-up, and 90 reported successful coitus at the end of that period: 79 patients (87.8%) with intracavernous injection and 11 (12.2%) without injection. The remaining 10 patients (10%) dropped out of the program, seven (7.0%) for health or marital reasons and three (3.0%) because of treatment failure. We conclude that a progressive program of intracavernous injections of vasoactive drugs may be a good alternative for the treatment of erectile dysfunction in patients with cardiovascular disease.

Dietary supplements and other alternative medicines for erectile dysfunction. What do I tell my patients?

Dietary supplements and other alternative medicines have enjoyed a tremendous amount of popularity and use over the past decade. Although, the prevalence of these therapies for erectile dysfunction (ED) is unknown at this time, numerous media outlets and alternative medicine publications seem to support the utilization of these therapies for ED. The placebo effect is approximately 25% (1 out of 4 benefit) from past randomized trials of FDA approved medications for ED. Adequate clinical trials are needed for dietary supplements for ED to access whether or not a benefit beyond a placebo effect exists. Clinicians should become aware of these supplements and the current research espousing or discouraging their use, and they should understand the adverse effects associated with them in order to effectively discuss these products with any patient inquiring about them.

The placebo effect and randomized trials: analysis of conventional medicine

Randomized controlled trials are generally regarded as the gold standard of study designs to determine causality. The inclusion of a placebo group in these trials, when appropriate, is critical to access the efficacy of a drug or supplement. The placebo response itself has received some attention in the medical literature over the past fifty years. The recent increasing utilization of dietary supplements and herbal medications by patients makes it imperative to reevaluate the placebo response in conventional and alternative medicine. This article will review a whole series of unique conditions (allergies/asthma, alopecia, BPH, erectile dysfunction, osteoporosis, weight loss...) and the placebo response associated with them from conventional medical randomized trials.

Efficacy results and quality-of-life measures in men receiving sildenafil citrate for the treatment of erectile dysfunction

The aim of the present study was to evaluate the efficacy of sildenafil citrate and its effects on quality of life (QoL) in men with erectile dysfunction (ED) using data from three multicenter, double-blind, placebo-controlled clinical trials. Efficacy was evaluated using a global efficacy question (improvement of erections) and questions from the International Index of Erectile Function (IIEF) addressing the ability to achieve and maintain erections. QoL directly related to ED was evaluated using questions 13 and 14 of the IIEF, several psychometric instruments, and a questionnaire addressing men's concerns about their erection problems. Seventy-nine [corrected] percent of patients receiving sildenafil reported improved erections compared with 23% of patients receiving placebo (p < 0.0001); also reported were improvements in the ability to achieve and maintain erections with sildenafil but not with placebo (p < 0.0001). Improvements were also seen for other aspects of sexual function (overall satisfaction with sex life, sexual relationships with partners, concerns about erectile problems, p < 0.0001) and general mental health (well-being, self-control, satisfaction with relationship, health relative to 1 year ago, mental health; p < or = 0.05) following treatment with sildenafil. Thus, treatment of ED with sildenafil can significantly improve key QoL parameters related to sexual dysfunction and general mental health.