Prescribing all phosphodiesterase 5 inhibitors to a patient with erectile dysfunction--a realistic and feasible option in everyday clinical practice--outcomes of a simple treatment regime

Availability of platelet-rich plasma for treatment of erectile dysfunction and associated costs and efficacy: A review of current publications and Canadian data

INTRODUCTION

Platelet-rich plasma (PRP) is an increasingly used unconventional treatment option for erectile dysfunction (ED). The validity of PRP as a potential treatment for ED has been proposed in limited human trials. Furthermore, the costs associated with PRP for ED treatment are not readily promoted to patients. The goal of this review was to determine the efficacy and costs of PRP based on currently available literature and Canadian data.

METHODS

A comprehensive literature review of available PRP studies and current published data pertaining to cost, availability, and provider clinics globally was conducted using the PubMed database. Physicians offering genital PRP in Canada were identified using internet searches and PRP provider directories. Physician qualifications, clinic locations, and cost information were obtained from provider websites and telephone calls to identified clinics.

RESULTS

Availability of PRP injections offered for treating ED is increasing globally. There are currently no peer-reviewed publications to substantiate anecdotal evidence pertaining to the efficacy of PRP as a viable treatment option for ED patients. Our results indicate 19 providers for PRP injections in Canada, costing on average $1777 CAD per injection. No providers were affiliated with academic institutions and providers varied in their area of clinical speciality and training.

CONCLUSIONS

To our knowledge, there is currently no research underway investigating the clinical efficacy of PRP for ED treatment despite its broad availability and significant cost. Patients should be informed of the lack of substantiated efficacy and safety data, as the reliability of PRP treatments requires further evaluation.

Recent advances in the understanding and management of erectile dysfunction

Erectile dysfunction (ED) is important to a man’s well-being and health, since it not only affects the individual but also causes strain on a couple’s lifestyle and relationship. There are multiple non-invasive treatments that exist for ED including lifestyle changes, oral medications (phosphodiesterase type 5 inhibitors), vacuum-assisted erectile devices, and intraurethral suppositories. While lifestyle changes and oral medications are typically first-line treatments for ED, more-invasive treatments including intracavernosal injections and surgically implanted prosthetic devices may be required for the management of complex cases. Additionally, novel therapies are currently being developed, and future treatment options may include shock-wave therapy, external prosthetic devices, and injection of stem cells or platelet-rich plasma. The current manuscript seeks to highlight advances in management and may eventually alter the treatment paradigm to allow more-inclusive care pathways.

Longitudinal recovery patterns of penile length and the underexplored benefit of long-term phosphodiesterase-5 inhibitor use after radical prostatectomy

BACKGROUND

Penile length (PL) shortening is an underreported phenomenon following radical prostatectomy (RP) and risk factors are not fully explored. We aimed to describe longitudinal patterns of PL recovery and evaluate factors predicting complete return to baseline PL.

METHODS

PL measurement was performed during a preoperative and postoperative follow-up visits at 7 days and 3, 6, 9, and 12 months. Patients who completely recovered (CR: N = 397) their preoperative stretched PL measured during at least one of their follow-up visits were compared to those with incomplete recovery (IR: N = 131). Recovery patterns were analyzed for both groups and were also compared in regards to demographics, nerve-sparing techniques, prostate size, cardiovascular risk profiles, and phosphodiesterase-5 inhibitor (PDE5i) uses. Logistic regression analyses were performed using age and other relevant clinicopathologic variables to predict PL recovery.

RESULTS

60.2% of the total study population regained their preoperative PL at 12 months. Average percent (length) differences from baseline were - 1.70% (- 0.25 cm) and - 16.42% (- 2.35 cm) in the CR and the IR groups, respectively (p < 0.001). Multivariate logistic regression demonstrated that younger age (OR 0.962; 95%CI 0.931-0.994; p = 0.019), high preoperative erectile function (EF) (OR 1.028; 95%CI 1.001-1.056; p = 0.046), and consistent PDE5i use (OR 1.998; 95%CI 1.166-3.425; p = 0.012) were independent predictors of CR. At 12-month follow up, PL difference for consistent PDE5iusers was statistically different from those who did not use PDE5i consistently (- 3.25%vs. -6.64%; P = 0.001).

CONCLUSION

Age, preoperative EF, and consistent use of PDE5i were associated with complete recovery of baseline PL after RP. The therapeutic effect of PDE5i was most pronounced at 12-month visit, suggesting an added benefit with long-term use.

Preference for erectile dysfunction treatments: Assessment by means of consumers preference analysis techniques

INTRODUCTION

Patient preference for erectile dysfunction (ED) treatments is of great importance for satisfaction and adherence. We have assessed the usefulness of the main technique for assessing consumer preferences (conjoint analysis) to analyze preferences towards these treatments. We also assessed the influence of age, frequency of sexual intercourse, co-morbidities, ED severity or having testosterone deficiency syndrome (TDS).

MATERIAL AND METHOD

Observational, cross-sectional, multicenter study in 626 men aged ≥18 years that had recently taken at least two different PDE5i, one being vardenafil orodispersible (ODT). Seven selected features of ED treatments were tested. Different series of scenarios (cards) were created by combining these features: two series of 4 features (9 cards), another one series of 7 (16 cards). Short series were tested in Primary Care, and the long series in Urology/Andrology offices. Influences were tested by rank ordered logistic regression analysis.

RESULTS

The feature «administration form» was consistently given the most relative importance; the ODT form was given the greatest utility. Consensus towards the most and least preferred treatment was achieved only in one of the short series tested. Only severity of TDS symptoms, or having the most frequent symptoms, influenced treatment preference. Influence was mild.

CONCLUSIONS

Conjoint analysis is a valid method for assessing preferences for ED treatments. A short series of highly selected attributes is advisable. Easiness and convenience of administration are of great importance for users. TDS symptomatology mildly affects preference.

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.

Patient preference and satisfaction in erectile dysfunction therapy: a comparison of the three phosphodiesterase-5 inhibitors sildenafil, vardenafil and tadalafil

Erectile dysfunction (ED) is a problem that may affect up to 52% of men between the ages of 40 and 70. It can be distressing because of its negative effect on self-esteem, quality of life, and interpersonal relationships. Oral phosphodiesterase-5 inhibitors (PDE5 inhibitors) are now the first choice of treatment in ED. The availability of three (sildenafil citrate, tadalafil, and vardenafil) well tolerated and effective oral PDE5 inhibitors gives treatment options for men with ED. Although the mechanism of action is the same for the three drugs, they differ in their pharmacokinetics. Several preference studies were conducted between the three PDE5 inhibitors but they were not free from bias. Because of the lack of overwhelming reliable data showing that one PDE5 inhibitor is superior to another, current opinion is that the individual patient should have the opportunity to test all three drugs and then select the one that best suits him and his partner.

The ENDOTRIAL study: a spontaneous, open-label, randomized, multicenter, crossover study on the efficacy of sildenafil, tadalafil, and vardenafil in the treatment of erectile dysfunction

INTRODUCTION

The three effective, commercially available drugs for the treatment of erectile dysfunction-sildenafil, vardenafil, and tadalafil-inhibit the same substrate, the erectolytic enzyme phosphodiesterase type 5 (PDE5). Although there are pharmacological differences between these three compounds, few comparative studies have been conducted to date.

AIM

The aim of this study was to determine the efficacy of sildenafil, tadalafil, and vardenafil in a randomly assigned 8-week fixed regimen.

METHODS

This was a spontaneous, open-label, randomized, multicenter, crossover study where the patients were randomized to receive sildenafil 50 mg, sildenafil 100 mg, tadalafil 20 mg, or vardenafil 20 mg.

MAIN OUTCOME MEASURES

The primary outcome included the posttreatment analysis of erectile function domains of the abridged International Index of Erectile Function (IIEF5+1). The secondary objectives included the analysis of peak-systolic velocities (PSVs), end-diastolic velocities (EDVs), and resistive index (RI), and the estimate of the percentage of men with normal penile hemodynamic parameters after each treatment.

RESULTS

In all groups of patients taking sildenafil 50 mg, sildenafil 100 mg, tadalafil 20 mg, and vardenafil 20 mg at a frequency reflecting the common treatment regimens in real life, there was a statistically significant baseline-to-end point improvement in subjective perception of erectile function measured by IIEF5+1. When the four groups were compared, the treatments were not different in modifying IIEF5+1 and penile flow parameters. However, the within-group analysis showed that PSV improved in the sildenafil 50 mg group and that PSV together with RI significantly ameliorated in patients receiving 100 mg of sildenafil. Regression analysis confirmed an independent effect of sildenafil on hemodynamic efficacy parameters.

CONCLUSIONS

An overall equivalence was demonstrated in the subjective perception of treatment benefits for all the PDE5i tested. However, sildenafil, in a dose-dependent manner, was the unique PDE5i able to ameliorate some of the penile flow parameters within the 8-week treatment period. These findings should be interpreted conservatively because of the observational nature of the study.

Evaluation of the safety and efficacy of sildenafil citrate for erectile dysfunction in men with multiple sclerosis: a double-blind, placebo controlled, randomized study

PURPOSE

We evaluated the safety and efficacy of sildenafil citrate for treating erectile dysfunction in patients with multiple sclerosis.

MATERIALS AND METHODS

A total of 203 patients with multiple sclerosis (age range 18 to 50 years old) with erectile dysfunction were randomly assigned to receive 50 to 100 mg sildenafil (102 patients in group 1) or a similar regimen of placebo (101 patients in group 2) 45 minutes to 2 hours before sexual stimulation. Patients were asked to use at least 24 doses/attempts at home. Primary outcome measures consisted of responses to questions 3 and 4 from the International Index of Erectile Function questionnaires well as responses to Sexual Encounter Profile diary questions 2 and 3. We also assessed the number of attempts at sexual intercourse, the number of attempts that were successful and adverse drug effects.

RESULTS

Improved erections (positive response to the Global Assessment Questionnaire) were reported by 32.8% of patients receiving sildenafil and 17.6% of those receiving placebo (p = 0.04). For Sexual Encounter Profile question 2 (successful penetration) the increase from baseline in mean per patient percentage of yes responses was 29.4% after sildenafil vs 18.8% after placebo (p = 0.04). The proportion of successful sexual attempts ranged from 12% to 26% for sildenafil and from 9% to 21% for placebo, respectively (p = 0.044). Of patients taking sildenafil and placebo 24 (23.5%) and 9 (8.9%) experienced 81 and 31 adverse events, respectively (p = 0.01).

CONCLUSIONS

Compared with placebo, sildenafil has little effect on multiple sclerosis emergent erectile dysfunction and, therefore, cannot be recommended for the routine treatment of erectile dysfunction in patients with multiple sclerosis. This finding implies that there must be other mechanisms that are not affected by sildenafil or are resistant to the effects of sildenafil.

Giving patients with erectile dysfunction the opportunity to try all three available phosphodiesterase type 5 inhibitors contributes to better long-term treatment compliance

INTRODUCTION

There are three phosphodiesterase type 5 (PDE5) inhibitors marketed, sildenafil, Vardenafil, and tadalafil for oral treatment of erectile dysfunction (ED). Although the treatment is simple and mostly effective, around 50% has ceased to use the medication within 2 years. One recently described way to improve the compliance is to let the patient try all the three PDE5 inhibitors and to prescribe the drug(s) he and his partner desires.

AIM

To study long-term compliance among patients who were treated according to this "three-drug regime."

MAIN OUTCOME MEASURES

Compliance and reasons for discontinuation after >2 years.

METHODS

The men who, during 2003, were enrolled in a treatment regime, where they had the opportunity to test all the three drugs and to chose the one(s) they preferred, were interviewed in 2006 by telephone concerning their ongoing ED treatment and the reason for discontinuation.

RESULTS

Of the 138 men, mean age 60 years (36-79 years), who had been enrolled and successfully treated with the three-drug regime, 127 (92%) could be reached. The mean follow-up time was 27 months (23-34 months). Of the 127 men, as many as 109 (86%) were still using PDE5 inhibitors. A few (8%) used more than two tablets per week. The majority (44%) used one to two tablets per week or one to two per month (43%), the others (5%) less often. The causes for discontinuation were varying. The most common reason (N = 7) was return of a satisfactory non-assisted erection. Seventy-five percent of the men used only one drug; the others switched between a short- and long-acting drug depending on the situation. It was not uncommon (25%) that the preference had changed during the 3 years of PDE5 inhibitor use.

CONCLUSION

To let patients with ED test the three available PDE5 inhibitors results in an unusually high compliance even under an extended period of time (>2 years).

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.