Evaluation of an alternative dosing regimen with tadalafil, three times per week, for men with erectile dysfunction: SURE study in Italy

Treatment preferences of patients with erectile dysfunction: a systematic review of randomized controlled trials

INTRODUCTION

Patients' treatment preferences (PTP) depend on the complex interaction of numerous patient- and treatment-related factors; their assessment can guide therapy and promote compliance of patients with erectile dysfunction (ED). We aimed to systematically describe the literature evaluating the treatment preferences of patients with ED, published in the last 25 years.

EVIDENCE ACQUISITION

A comprehensive bibliographic search of multiple databases was conducted in June, 2023. The literature search was limited to the articles published since 1998. Articles were deemed eligible if they described male patients with ED (P) undergoing treatment for this condition (I) compared with other treatments, placebo or sham therapy (C), and reported PTP (O). Only randomized controlled trials (RCTs) and post-hoc analyses of RCTs were selected (S). The data were presented in a narrative fashion. The risk of bias (RoB) was evaluated using the RoB 2 tool and the Mulhall-Montorsi model.

EVIDENCE SYNTHESIS

A total 14 RCTs evaluating 6,841 patients and 4 post-hoc analyses of RCTs were included. All RCTs were considered to be at high RoB. No validated tool was used to investigate PTP. Sildenafil was the most frequently evaluated ED treatment (9 RCTs). Sildenafil was chosen over placebo by 78-100% of subjects and over ICI in 70% of patients due to its easier route of administration. No significant difference in patient preference was recorded between Sildenafil tablets and orodispersible (53% vs. 47%, P>0.05). Tadalafil was preferred over Sildenafil by 66-73% of patients (P<0.05), mainly because it allowed an erection long after taking the drug (55-67%). Tadalafil as-needed was chosen over Tadalafil 3 times/week by 57-59% of the patients (P<0.05).

CONCLUSIONS

The available RCTs support the preference of ED patients for Sildenafil over ICI, Tadalafil over Sildenafil, and Tadalafil as-needed over Tadalafil 3 times/week. However, these findings should be considered at high RoB.

Comparison of efficacy and satisfaction profile, between penile prosthesis implantation and oral PDE5 inhibitor tadalafil therapy, in men with nerve-sparing radical prostatectomy erectile dysfunction

WHAT'S KNOWN ON THE SUBJECT? AND WHAT DOES THE STUDY ADD?: Erectile dysfunction after nerve-sparing radical retropubic prostatectomy constitutes a challenge to the urologist. The mainstay of medical treatment after radical prostatectomy to restore spontaneous erectile function remains phosphodiesterase (PDE5) inhibitors, despite the fact that data from animal studies suggesting that PDE5 inhibitors can prevent smooth muscle apoptosis and fibrosis have not yet been extrapolated to humans because of a lack of standardized protocols. If the above treatment fails, second-line therapies such as intraurethral prostaglandins, penile injection therapy and vacuum devices are offered. When less invasive therapies are ineffective, interventions that preserve sexual function such as penile prosthesis implantation become the treatment of choice. Our study reveals the alternative of penile prosthesis implantation as first-line treatment in erectile dysfunction after nerve-sparing radical prostatectomy. It also highlights its superiority to the oral PDE5 inhibitor treatment, regarding the erection, frequency, firmness, maintenance and penetration ability. This suggests that a concept of an early penile intervention in the future would be promising for those patients who wish to remain sexually active without depending on oral formulations with doubtful and delayed results.

OBJECTIVE

To evaluate the outcome of penile prosthesis surgery in comparison to oral phosphodiesterase type 5 (PDE5) inhibitor administration, in men with erectile dysfunction after nerve-sparing radical prostatectomy, as early penile intervention therapy.

PATIENTS AND METHODS

A total of 174 patients treated by nerve-sparing retropubic radical prostatectomy (RRP) for clinically localized prostate cancer, between January 2006 and September 2009 enrolled in the study, 153 patients fulfilled the inclusion criteria, and 69 (45%) patients presented with post-RRP erectile dysfunction 6 months after primary surgery. Fifty-four patients were disease-free and subdivided into two arms according to treatment modality, either tadalafil three times/week or penile prosthesis implantation. All patients were evaluated using the International Index of Erectile Function (IIEF) questionnaire preoperatively and at 6, 12 and 24 month postoperatively. Repeated measurements analysis of variance was conducted to evaluate the effect of time and group on IIEF total score.

RESULTS

There was a significant reduction in IIEF score from preoperative values to the first measurement after surgery in both treatment groups. The overall degree of change from the first time point immediately after surgery to 2 years was greater in the penile prosthesis group than the tadalafil group (20.4 ± 1.3 vs 8.1 ± 2.4, P < 0.001).

CONCLUSIONS

The efficacy and satisfaction results of both treatment types are considered acceptable. However, regarding the erection frequency, firmness, penetration ability, maintenance and erection confidence it seems that penile prosthesis implantation is superior to oral treatment. The concept of early penile intervention should be considered and is promising for all patients with post-RRP erectile dysfunction.

Effect of tadalafil in chronic renal failure rabbits: relevance to erectile dysfunction

It is of great importance to investigate an effective and reliable medication against chronic renal failure (CRF)-related erectile dysfunction (ED), which aims to improve patients' life qualities. The concentrations of cyclic guanosine monophosphate (cGMP) in the corpus cavernosal smooth muscle of both CRF and control rabbits were measured. The effects of various concentrations of tadalafil, papaverine, and sodium nitroprusside on the relaxation responses of corpus cavernosal smooth muscle pre-contracted with phenylephrine in CRF rabbits were observed. There was significant difference in the concentration of cGMP between CRF and control rabbits (P<0.01). Tadalafil had the greatest impacts on CRF rabbits when given the same concentration of papaverine or sodium nitroprusside and particularly significant differences were identified under the concentration levels of 10⁻⁵ and 10⁻⁴ mol/L (P<0.01). The results suggest that the cGMP concentrations of the corpus cavernosum had been greatly reduced in CRF rabbits compared with control rabbits and that tadalafil may be an ideal medication for use in the treatment of CRF-related ED.

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.