Long-term safety and tolerability of tadalafil in the treatment of erectile dysfunction

Differences in ocular adverse events associated with phosphodiesterase-5 inhibitors: a real-world pharmacovigilance study

OBJECTIVE

Our study aims to characterize the ocular safety profiles of phosphodiesterase type 5 (PDE5) inhibitors and explore the differences among different PDE5 inhibitors.

METHODS

We analyzed reports on ocular adverse events associated with sildenafil, vardenafil and tadalafil submitted to the FDA Adverse Event Reporting System (FAERS) database from the first quarter of 2004 to the first quarter of 2023. Disproportionality analysis was conducted to evaluate reporting risk profiles.

RESULTS

Among 61,211 reports qualifying for analysis, 5,127 involved sildenafil, 832 vardenafil, and 3,733 tadalafil. All PDE5 inhibitors showed increased reporting odds ratios (ROR) for ocular adverse events, with vardenafil highest (ROR 4.47) followed by sildenafil and tadalafil. Key ocular adverse events included cyanopsia, optic ischemic neuropathy, visual field defects, unilateral blindness and blindness. Sildenafil showed the highest disproportionality for cyanopsia (ROR 1148.11) while vardenafil and tadalafil showed the highest disproportionality for optic ischemic neuropathy. Time-to-onset analysis also revealed significant differences, with sildenafil having a later median time-to-onset compared to vardenafil and tadalafil.

CONCLUSIONS

This comprehensive pharmacovigilance study reveals distinct patterns of ocular adverse events associated with PDE5 inhibitors. These findings contribute to a better understanding of the safety profiles of PDE5 inhibitors and may guide healthcare professionals in clinical decision-making.

Long-term tadalafil once daily in Chinese men with erectile dysfunction: a 2-year final analysis of a post-marketing, multicenter, randomized, open-label trial

The long-term safety and effectiveness of once-daily tadalafil is crucial, but limited data are available in Chinese patients with erectile dysfunction (ED). In this post-marketing, multicenter, randomized, open-label trial with 2-year follow-up, 635 ED cases were randomized to receive daily oral tadalafil 2.5 mg or 5 mg for 3 months, of whom 580 continued once-daily tadalafil 5 mg for 21 months. Treatment-emergent adverse events in the 12-month and 24-month period were similar, with the most common being viral upper respiratory tract infection, upper respiratory tract infection, and headache. Significant improvement from baseline in the International Index of Erectile Function-Erectile Function (IIEF-EF) score was detected at month 12 (least squares mean [LSM] change: 7.9, 95% confidence interval [CI]: 7.5-8.4, P < 0.001) and was maintained to month 24 (LSM change: 8.6, 95% CI: 8.1-9.0, P < 0.001). The proportions of patients regaining normal erectile function (IIEF-EF score ≥26) were 43.7% and 48.0% at months 12 and 24, respectively. Global Assessment Questionnaire results showed improved erection function in 97.5% of patients and improved ability to engage in sexual activity in 95.9% of patients at month 12; these values were 96.1% and 95.0% at month 24, respectively. The quality of sexual life score based on the Sexual Life Quality Questionnaire (SLQQ) was increased by 52.2% at month 12 and by 55.3% at month 24 (both P < 0.001). The treatment satisfaction score determined by SLQQ (mean ± standard deviation) was 62.4 ± 21.0 at month 12 versus 65.9 ± 20.2 at month 24. Two-year daily application of tadalafil 5 mg in Chinese men with ED showed a favorable safety profile and durable improvement in sexual performance and satisfaction.

Diabetes-induced male infertility: potential mechanisms and treatment options

Male infertility is a physiological phenomenon in which a man is unable to impregnate a fertile woman during a 12-month period of continuous, unprotected sexual intercourse. A growing body of clinical and epidemiological evidence indicates that the increasing incidence of male reproductive problems, especially infertility, shows a very similar trend to the incidence of diabetes within the same age range. In addition, a large number of previous in vivo and in vitro experiments have also suggested that the complex pathophysiological changes caused by diabetes may induce male infertility in multiple aspects, including hypothalamic-pituitary-gonadal axis dysfunction, spermatogenesis and maturation disorders, testicular interstitial cell damage erectile dysfunction. Based on the above related mechanisms, a large number of studies have focused on the potential therapeutic association between diabetes progression and infertility in patients with diabetes and infertility, providing important clues for the treatment of this population. In this paper, we summarized the research results of the effects of diabetes on male reproductive function in recent 5 years, elaborated the potential pathophysiological mechanisms of male infertility induced by diabetes, and reviewed and prospected the therapeutic measures.

Long-Term Outcomes of Drug-Eluting Stent Implantation for Patients With Atherosclerotic Erectile Dysfunction not Responding to PDE-5-Inhibitors

PURPOSE

Endovascular therapy of erection-related arteries was shown to be a promising treatment option for patients with severe erectile dysfunction. Purpose of this study was to assess the longer-term safety and clinical success rate of endovascular revascularization of erection-related arteries with the Angiolite BTK stent in patients with arteriogenic erectile dysfunction.

MATERIALS AND METHODS

A total of 147 consecutive men (63.5±9.3 years) with erectile dysfunction due to 345 atherosclerotic lesions underwent endovascular revascularization. Patients received an International Index of Erectile Function (IIEF)-15 questionnaire at 30.3±7.2 months (follow-up [FU] period no less than 18 months) after stenting. An improvement by 4 points in the erectile function domain consisting of 6 questions (IIEF-6) was defined as minimal clinically important difference (MCID).

RESULTS

Technical success was achieved in 99% of lesions. One major adverse event occurred after endovascular revascularization. Sixty-eight (46%) patients completed their latest FU at least 18 months following the last intervention. Minimal clinically important difference was achieved in 54% (37/68) of patients.

CONCLUSIONS

In patients with arteriogenic erectile dysfunction not responding to phosphodiesterase-5-inhibitors (PDE-5-Is), endovascular therapy with a novel thin-strut sirolimus-eluting stent is a safe and effective treatment option during short- and longer-term FU.

CLINICAL IMPACT

Patients with severe erectile dysfunction profit greatly from endovascular therapy of erection-related arteries. Stable clinical outcomes are seen beyond a 1-year timeframe. It is proven that, the drug-eluting stent therapy for atherosclerotic ED in patients who have not responded to PDE-5-I therapy is safe and effective during longer-term follow-up.

Efficacy and Safety of Udenafil Once Daily in Patients with Erectile Dysfunction after Bilateral Nerve-Sparing Robot-Assisted Laparoscopic Radical Prostatectomy: A Randomized, Double-Blind, Placebo-Controlled Study

PURPOSE

To evaluate the efficacy and safety of udenafil 75 mg once daily in patients with erectile dysfunction following bilateral nerve-sparing robot-assisted laparoscopic radical prostatectomy (BNS-RALP).

MATERIALS AND METHODS

A multi-center, prospective, randomized, controlled, double-blind study was conducted. Among patients with localized prostate cancer with international index of erectile function-erectile function domain (IIEF-EF) score of 18 or higher before BNS-RALP, those who developed postoperative erectile dysfunction (IIEF-EF score 14 or less at 4 weeks after BNS-RALP) were enrolled. Enrolled patients were randomly assigned to the udenafil 75 mg daily group or the placebo group in a 2:1 ratio. Each subject was followed up at 8 weeks (V2), 20 weeks (V3), and 32 weeks (V4) to evaluate the efficacy and safety of udenafil.

RESULTS

In all, 101 patients were screened, of whom 99 were enrolled. Of the 99 patients, 67 were assigned to the experimental group and 32 to the control group. Ten (14.93%) patients in the experimental group and 10 (31.25%) in the control group dropped out of the study. After 32 weeks of treatment, IIEF-EF score of 22 or higher was seen in 36.51% (23/63) of patients in the experimental group and 13.04% (3/23) patients in the control group (p=0.021). The proportion of patients with IIEF-EF improvement of 25% or more compared to the baseline was 82.54% (52/63) in the experimental group and 62.96% (17/27) in the control group (p=0.058).

CONCLUSIONS

Udenafil 75 mg once daily after BNS-RALP improved the erectile function without any severe adverse effects.

Strategies to safely target widely expressed soluble adenylyl cyclase for contraception

In humans, the prototypical second messenger cyclic AMP is produced by 10 adenylyl cyclase isoforms, which are divided into two classes. Nine isoforms are G protein coupled transmembrane adenylyl cyclases (tmACs; ADCY1-9) and the 10th is the bicarbonate regulated soluble adenylyl cyclase (sAC; ADCY10). This review details why sAC is uniquely druggable and outlines ways to target sAC for novel forms of male and female contraception.

Analysis of integrated clinical safety data of tadalafil in patients receiving concomitant antihypertensive medications

This pooled safety analysis assessed the incidence of hypotension‐related treatment‐emergent adverse events (TEAEs) and major adverse cardiovascular events (MACEs) in patients with concomitant use of tadalafil and antihypertensive medications. Data were pooled from seventy‐two Phase II–IV studies conducted on patients with a diagnosis of erectile dysfunction (ED) and/or benign prostate hyperplasia (BPH). Studies were categorized as either All placebo‐controlled studies or All studies. The incidences of hypotension‐related TEAEs and MACEs were analyzed by indication; by use of concomitant antihypertensive medications; and by the number of concomitant antihypertensive medications. A total of 15 030 and 22 825 patients were included in the analyses for All placebo‐controlled studies and All studies, respectively. In the All placebo‐controlled studies, the incidence of hypotension‐related TEAEs and MACEs was ranging between 0.6–1.5% and 0.0–1.0%, respectively, across all indications. Tadalafil was associated with an increase in hypotension‐related TEAEs only in the ED as‐needed group not receiving any concomitant antihypertensive medications (p‐value = .0070); no significant difference was reported between placebo and tadalafil in the groups of patients receiving ≥1 antihypertensive medication (p‐values ≥ .7386). Similarly, no significant differences (p‐values≥ .2238) were observed in the incidence of MACEs between tadalafil and placebo treatment groups, with or without concomitant use of antihypertensive medications, and across all indication categories. In the All studies group, results were similar. The pooled analysis showed no evidence that taking tadalafil alongside antihypertensive medications increases the risk of hypotension‐related TEAEs or MACEs compared with antihypertensive medications alone.

Evaluating the quality of asynchronously- versus synchronously-delivered virtual care: Differences in rates of reported medication side effects among patients with erectile dysfunction on a direct-to-consumer telehealth platform

Background

Asynchronous health care encounters are becoming an increasingly mainstream form of telehealth. While synchronous phone or video visits have become more widely accepted, US policymakers and other key health care stakeholders have been hesitant to fully embrace asynchronous diagnosis and treatment. This is particularly true in the context of direct-to-consumer (DTC) platforms, where encounters are patient-initiated and there is no preestablished relationship with a provider. This hesitation is compounded by limited research comparing outcomes between asynchronous and synchronous care, especially in the DTC context.

Objective

The purpose of this study was to explore whether asynchronous care leads to different patient outcomes in the form of medication-related adverse events when compared to synchronous virtual care.

Methods

Using 10,000 randomly sampled patient records from a prominent US-based DTC platform, we analyzed the rates of patient-reported side effects from commonly prescribed erectile dysfunction medications and compared these rates across modalities of treatment.

Results

Asynchronous care resulted in lower but nonsignificant differences in the rates of the reported drug-related side effects compared to synchronous treatment.

Conclusions

In some circumstances, such as treatment for erectile dysfunction, asynchronous care can offer the same level of safety in prescribing when compared to synchronous care. More research is needed to evaluate the safety of asynchronous care across a wider set of conditions and measures.

Update of the position paper on arterial hypertension and erectile dysfunction

: Sexual health is an integral part of overall health, and an active and healthy sexual life is an essential aspect of a good life quality. Cardiovascular disease and sexual health share common risk factors (arterial hypertension, diabetes mellitus, dyslipidemia, obesity, and smoking) and common mediating mechanisms (endothelial dysfunction, subclinical inflammation, and atherosclerosis). This generated a shift of thinking about the pathophysiology and subsequently the management of sexual dysfunction. The introduction of phosphodiesterase type 5 inhibitors revolutionized the management of sexual dysfunction in men. This article will focus on erectile dysfunction and its association with arterial hypertension. This update of the position paper was created by the Working Group on Sexual Dysfunction and Arterial Hypertension of the European Society of Hypertension. This working group has been very active during the last years in promoting the familiarization of hypertension specialists and related physicians with erectile dysfunction, through numerous lectures in national and international meetings, a position paper, newsletters, guidelines, and a book specifically addressing erectile dysfunction in hypertensive patients. It was noted that erectile dysfunction precedes the development of coronary artery disease. The artery size hypothesis has been proposed as a potential explanation for this observation. This hypothesis seeks to explain the differing manifestation of the same vascular condition, based on the size of the vessels. Clinical presentations of the atherosclerotic and/or endothelium disease in the penile arteries might precede the corresponding manifestations from larger arteries. Treated hypertensive patients are more likely to have sexual dysfunction compared with untreated ones, suggesting a detrimental role of antihypertensive treatment on erectile function. The occurrence of erectile dysfunction seems to be related to undesirable effects of antihypertensive drugs on the penile tissue. Available information points toward divergent effects of antihypertensive drugs on erectile function, with diuretics and beta-blockers possessing the worst profile and angiotensin receptor blockers and nebivolol the best profile.

Effect of Phosphodiesterase-5 Inhibitors on the Treatment of Male Infertility: A Systematic Review and Meta-Analysis

Purpose

Male infertility is a worldwide problem with limitations in the treatment. Phosphodiesterase-5 inhibitors (PDE5is) is the first choice for the treatment of erectile dysfunction, more and more studies show that it has a certain effect on male infertility in recent years. But there was currently no high quality of systematic review to evaluate the effects of PDE5is on semen quality.

Materials and Methods

We retrieved the electronic databases of MEDLINE, PubMed, Web of Science, EMBASE, etc. Related randomized controlled trials (RCTs) were collected and selected up to May 20, 2020. We have searched literature with terms “male infertility”, “phosphodiesterase-5 inhibitors”, “PDE5i”, “Tadalafil”, “Sildenafil”, “Vardenafil”, “Udenafil”, “Avanafil”, “semen”, and “sperm”. Mean value and its standard deviation were used to perform quantitative analysis. All statistical analyses were conducted by RevMan 5.3 and Stata software.

Results

There were a total of 1,121 participants in the nine included studies. There was a statistically significant improvement treated with PDE5is compared with sham therapy, which including sperm concentration (mean difference [MD]=1.96, 95% confidence interval [CI]=1.70–2.21, p<0.001; MD=3.22, 95% CI=1.96–4.48, p<0.001), straight progressive motility (%) Grade A (MD=3.71, 95% CI=2.21–5.20, p<0.001), sperm motility (MD=8.09, 95% CI=7.83–8.36, p<0.001), morphologically normal spermatozoa (%) (MD=0.67, 95% CI=0.20–1.15, p=0.005; MD=1.27, 95% CI=0.02–2.52, p=0.05), sperm abnormalities (%) (MD=−0.64, 95% CI=−0.81–−0.47, p<0.001), and progressive motile sperm (MD=5.34, 95% CI=3.87–6.81, p<0.001).

Conclusions

In this meta-analysis of nine RCTs, treatment with PDE5is could improve some indicators of male sperm.

Endovascular Therapy for Arteriogenic Erectile Dysfunction With a Novel Sirolimus-Eluting Stent

BACKGROUND

Arteriogenic erectile dysfunction is a common disease oftentimes not satisfactory treatable with medical therapy.

AIM

To assess the safety and clinical success rate of endovascular revascularization of erection-related arteries with the angiolite BTK stent in patients with arteriogenic erectile dysfunction.

METHODS

A total of 100 consecutive men (61.8 ± 10 years) with atherosclerotic lesions in erection-related arteries agreed to participate and were included into a single-center all-comers registry. Endovascular therapy with angiolite BTK drug-eluting stents was performed on a total of 211 lesions. Patients received a baseline International Index of Erectile Function (IIEF)-15 questionnaire at first presentation and 3 and 12 months after stenting. An improvement by 4 points in the erectile function domain consisting of 6 questions (IIEF-6) was defined as minimal clinically important difference. A total of 24 patients with 52 stented arterial lesions underwent angiographic follow-up of the initially treated arterial side during secondary revascularization of the contralateral side (angiographic sub-study).

OUTCOME

Clinical improvement of erections in 100 patients undergoing endovascular revascularization of erection-related arteries.

RESULTS

No major adverse events occurred during endovascular revascularization or within 30 days thereafter. Technical success was achieved in all lesions and procedural success in all patients. At 1 year, 55 of 97 patients (56.7%) improved by at least 4 points in IIEF-6 score and thus achieved a clinically relevant improvement of erectile function.In the angiographic sub-study, arterial patency and binary restenosis were observed in 46 of 52 (88.5%) and in 8 of 52 (15.4%), respectively, after a mean follow-up of 9.6 ± 5.8 months.

CLINICAL IMPLICATIONS

In patients with arteriogenic erectile dysfunction, endovascular therapy with a novel thin-strut sirolimus eluting stent is a safe and feasible treatment option.

STRENGTHS & LIMITATIONS

This real-world arterial revascularization registry included patients with a multitude of risk factors for ED, thereby representing the heterogeneity in patients in the clinical practice, which is one of its strengths but also one of its weaknesses. Another strength was the focus being laid on analyzing outcomes of patients with arteriogenic ED using only a single endovascular device. Further studies are warranted to better define subgroups of patients with impaired clinical outcomes.

CONCLUSION

Within the present all-comers registry, endovascular therapy of erectile dysfunction with the angiolite BTK stent was shown to be a safe and feasible treatment option resulting in clinical improvement rates comparable to earlier clinical trials although also showing that further research is warranted to define patient subgroups with particular benefits of endovascular therapy. Schönhofen J, Räber L, Knöchel J, et al. Endovascular Therapy for Arteriogenic Erectile Dysfunction With a Novel Sirolimus-Eluting Stent. J Sex Med 2021;18:315-326.

Considerations for prescribing pharmacotherapy for the treatment of erectile dysfunction

Introduction: The effectiveness of phosphodiesterase type 5 inhibitors (PDE5i) in treating erectile dysfunction (ED) creates a new field of both medical practice and pharmaceutical manufacturing. Both paved the way for emerging minimally invasive therapies to restore male sexual function. However, what is the best drug to achieve the optimum outcome is still a challenging question to be answered.Areas covered: The general viewpoint of matching the pharmacotherapeutic characteristics with the patient's medical, social, and psychological variables, in order to balance between efficacy and safety. Several studies had investigated considerations for preference and long-term adherence for PDE5i. However, a thorough investigation of considerations for prescribing ED pharmacotherapy is still lacking in the literature. This is the aim of this manuscript.Expert opinion: Several issues should be considered in the planning of ED management such as the patient's and partner's expectations, etiologic considerations, performance status, safety, adverse effects, ease of administration, compliance, bad experiences with previous treatment, availability, cost, social factors, satisfaction, and finally, regimen considerations. Addressing the patient's and partner's individual needs help to tailoring treatment in order to minimize compromises and optimize gains.

Role of application of tadalafil 5 mg once-daily (≥6 months) in men with erectile dysfunction from six randomized controlled trials

This meta-analysis was performed to assess the efficacy and safety of taking tadalafil 5 mg once-daily for at least 6 months in the treatment of erectile dysfunction (ED). Based on databases: MEDLINE, EMBASE and Cochrane Controlled Trials Register, this analysis was performed to collect randomized controlled trials (RCTs) of tadalafil 5mg once-daily in treating ED over 6 months. Reviewers also investigated the references of each literature. The meta-analysis covered a total of 1,596 patients in six RCTs. The tadalafil group performed a better effect in terms of the international index of erectile function-erectile function (IIEF) domain (P=0.005) for the treatment of ED compared with the placebo group. Safety assessments including discontinuations due to adverse events (AEs) (P=0.31) and treatment-emergent AEs (P=0.06) indicated that the tadalafil group had a better tolerate. The analysis elucidates that the dose of 5 mg per day of tadalafil showed a good effect after the treatment of at least 6 months relative to the control group with fewer side effects.

Men's beliefs about treatment for erectile dysfunction-what influences treatment use? A systematic review

Successful treatment of erectile dysfunction (ED) is associated with improvements in quality of life; however, treatment utilisation is sub-optimal. The aim of this systematic review was to identify the rates of ED treatment utilisation and the barriers and enablers men experience when using treatment. We searched: MEDLINE^®, Embase, the Cochrane library; AMED; HMIC; HTA; CINAHL; PsychARTICLES; PsychINFO up to August 2018. Data on rates of treatment utilisation and barriers and enablers of utilisation were extracted and summarised. Fifty studies were included. Discontinuation rates ranged from 4.4 to 76% for phosphodiesterase type 5 inhibitors, 18.6 to 79.9% for intracavernosal injections, and 32 to 69.2% for urethral suppositories. In relation to those with a penile prosthesis, 30% discontinued having sex due to, e.g. device complications, lack of partner or a loss of sexual interest. Most research included in the current review examined barriers to treatment utilisation and therefore focussed on reasons for discontinuing treatment. However, a small number explored factors that men found helpful with regards to treatment utilisation. The most prevalent barriers to utilisation were treatment ineffectiveness, side effects, the quality of men's intimate relationships and treatment costs. With regards to treatment enablers, the most salient finding was that men who reported side effects to a healthcare professionals (HCPs) were significantly less likely to discontinue treatment. There were limitations in methodology in that the studies did not use validated measures of treatment utilisation or barriers and enablers and no study used psychological theory to inform the examination of factors that influenced treatment utilisation. This review identifies a number of influential factors relating to ED treatment utilisation and highlights the importance of men's beliefs with regards to ED and its treatment. Beliefs are potentially modifiable and therefore the findings of this review highlight important considerations for HCPs with regards to supporting men to make better use of treatment.

Effect of phosphodiesterase-5 inhibitors (PDE5is) on the treatment of male infertility: A protocol for systematic review and meta-analysis

BACKGROUND

Male infertility is a worldwide problem with limitations in the treatment. Phosphodiesterase-5 inhibitors (PDE5is) is the first choice for the treatment of erectile dysfunction (ED), but more and more studies show that it has a certain effect on male infertility in recent years. The literatures of PDE5is related to male infertility have shown inconsistent results, and there is currently no high quality of systematic review to evaluate the effects of PDE5is on semen quality in male infertility patients.

METHODS

The electronic databases of MEDLINE, PubMed, Web of Science, EMBASE, Clinicaltrials.org, China National Knowledge Infrastructure Database (CNKI), Wan fang Database, China Biology Medicine Database (CBM), VIP Science Technology Periodical Database, Chinese Clinical Trial Registry and Cochrane Library were retrieved. Grey literature will be searched in Open Grey. Related Randomized controlled trials (RCTs) were collected and selected before October 20, 2019. We will search English literature and Chinese literature with search terms "male infertility", "phosphodiesterase-5 inhibitors", "PDE5i", "Tadalafil", "Sildenafil", "Vardenafil", "Udenafil", "Avanafil", "semen" and "sperm". Sperm concentration, motility and morphology, sperm DNA fragmentation index, number of per ejaculate, sperm viability and adverse events will be evaluated. RevMan 5.3 and Stata 14.0 will be used for Systematic review and Meta-analysis. This protocol reported in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses Protocols (PRISMA-P) statement, and we will report the systematic review by following the PRISMA statement.

CONCLUSION AND DISSEMINATION

Efficacy and safety of PDE5is on male sperm quality in infertile men will be assessed. The results will be published in a public issue journal to provide evidence-based medical evidence for urologists and andrologists to make clinical decisions.

REGISTRATION INFORMATION

PROSPERO CRD42019142980.

Therapeutic Strategies for Erectile Dysfunction With Emphasis on Recent Approaches in Nanomedicine

This review addressed erectile dysfunction, regarding pathophysiology and therapeutic strategies. The line of treatment includes phosphodiesterase type-5 inhibitors and other types of therapy like topical and stem-cell transplant. Scientific literature was assessed to investigate the impact of nanotechnology on erectile dysfunction therapy. Various nanotechnology approaches were applied, like vesicular systems, lipid-based carriers, nanocrystals, dendrimers, liquid crystalline systems and nanoemulsions. Smart nano-systems can alter the landscape of the modern pharmaceutical industry by re- investigation of pharmaceutically suboptimal but biologically active entities for treatment of erectile dysfunction which were previously considered undeveloped.

Effect of Ticagrelor, a Cytochrome P450 3A4 Inhibitor, on the Pharmacokinetics of Tadalafil in Rats

Tadalafil is a cytochrome P450 (CYP) 3A4 substrate. Because there are few data on drug-drug interactions, it is advisable to take sufficient consideration when co-administering tadalafil with CYP3A4 inducers or inhibitors. This study was conducted to assess the effect of ticagrelor, a CYP3A4 inhibitor, on the pharmacokinetic properties of tadalafil after oral administration to rats. A total of 20 Sprague–Dawley male rats were randomly divided into the non-pretreated group and ticagrelor-pretreated group, and tadalafil was orally administered to each group after pretreatment with or without ticagrelor. Blood samples were collected at predetermined time points after oral administration of tadalafil. As a result, systemic exposure of tadalafil in the ticagrelor-pretreated group was significantly increased compared to the non-pretreated group (1.61-fold), and the clearance of tadalafil in the ticagrelor-pretreated group was significantly reduced than the non-pretreated group (37%). The prediction of the drug profile through the one-compartment model could explain the differences of pharmacokinetic properties of tadalafil in the non-pretreated and ticagrelor-pretreated groups. This study suggests that ticagrelor reduces a CYP3A-mediated tadalafil metabolism and that tadalafil and a combination regimen with tadalafil and ticagrelor requires dose control and specific pharmacotherapy.

Efficacy and safety of combination of tadalafil and aspirin versus tadalafil or aspirin alone in patients with vascular erectile dysfunction: a comparative randomized prospective study

PURPOSE

We aimed to investigate the efficacy and safety of tadalafil, aspirin, and tadalafil + aspirin combination therapy in vascular erectile dysfunction (VED).

METHODS

A total of 336 patients were randomly divided into four groups (group 1, aspirin 100 mg/day, 126 patients; group 2, tadalafil 5 mg/day, 72 patients; group 3, tadalafil 5 mg + aspirin 100 mg, 72 patients; group 4, placebo, 66 patients). In all groups, the changes from baseline to end point in erectile function scores on the International Index of Erectile Function (IIEF-EF) and the number of patients who answered "yes" to questions 2 and 3 of the sexual encounter profile(SEP) were compared statistically.

RESULTS

The changes in IIEF-EF scores after treatment were 7.2 ± 4.4, 7.3 ± 4.3, 7.5 ± 4.4, and 2.0 ± 4.6 for group 1 (p < 0.0001), group 2 (p < 0.0001), group 3 (p < 0.0001), and group 4 (p = 0.0204), respectively. The change in SEP-2 ratios after treatment were 36.6%, 36.9%, 41.7%, and 9.4% for group 1 (p < 0.0001), group 2 (p < 0.0001), group 3 (p < 0.0001), and group 4 (p = 0.2925), respectively. The change in SEP-3 ratios after treatment was 46.6%, 49.2%, 53.7%, and 12.5% for group 1 (p < 0.0001), group 2 (p < 0.0001), group 3 (p < 0.0001), and group 4 (p = 0.1456), respectively. In group 2, both the number of patients who reported side effects (p < 0.0001) and stopped using the drug due to side effects (p < 0.05) were significantly higher than the control and others groups.

CONCLUSIONS

Successful results were obtained by tadalafil and aspirin monotherapy and tadalafil + aspirin combination therapy in patients with VED. However, the least side effect was observed in the tadalafil + aspirin group. Aspirin can be used alone in the treatment of patients with VED, or combined with tadalafil to reduce side effects and increase success.

Current guideline recommendations and analysis of evidence quality on low-intensity shockwave therapy for erectile dysfunction

Erectile dysfunction (ED) is defined as the inability to attain and maintain erection of the penis sufficient to permit satisfactory sexual activity. ED most commonly affects men from 40 years of age with a clear age-associated increase in prevalence. The condition may have significant negative impact on quality of life for both the patients and their partners. Over recent years, low-intensity shockwave therapy (LIST) has gained popularity in the treatment of ED, based on the assumption that LIST application may result in neoangiogenesis and thus increased blood flow to the corpora cavernosa. The increasing usage of LIST is contrasting with current guidelines, with the EAU guideline on ED stating that LIST can be used in mild organic ED patients or poor responders to PDE5I's, but with a weak strength of recommendation. In the AUA guideline on ED, the panel makes a conditional recommendation of grade C that LIST should be considered investigational. In this review, we will briefly review practice patterns, and critically discuss the evidence based on which these guideline statements have been made.

From rapalogs to anti-aging formula

Inhibitors of mTOR, including clinically available rapalogs such as rapamycin (Sirolimus) and Everolimus, are gerosuppressants, which suppress cellular senescence. Rapamycin slows aging and extends life span in a variety of species from worm to mammals. Rapalogs can prevent age-related diseases, including cancer, atherosclerosis, obesity, neurodegeneration and retinopathy and potentially rejuvenate stem cells, immunity and metabolism. Here, I further suggest how rapamycin can be combined with metformin, inhibitors of angiotensin II signaling (Losartan, Lisinopril), statins (simvastatin, atorvastatin), propranolol, aspirin and a PDE5 inhibitor. Rational combinations of these drugs with physical exercise and an anti-aging diet (Koschei formula) can maximize their anti-aging effects and decrease side effects.

Administration of daily 5 mg tadalafil improves endothelial function in patients with benign prostatic hyperplasia

INTRODUCTION

Tadalafil is a promising phosphodiesterase (PDE) 5 inhibitor prescribed for erectile dysfunction (ED). Daily low dose (5 mg) of tadalafil has also been used for the treatment of male lower urinary tract symptoms (LUTS) associated with benign prostate hyperplasia (BPH). PDE5 inhibitors induce relaxation of smooth muscle cells in the urethra, prostate, bladder neck, and blood vessels. The aim of this study was to investigate the efficacy of tadalafil on vessels endothelial function, in patients with male LUTS symptoms associated with BPH.

METHODS

The Institutional Review Board (IRB) approved this clinical study and informed consents had been obtained from 81 BPH patients. The following male LUTS parameters: international prostate symptom score (IPSS), overactive bladder symptom score (OABSS), voiding volume, max and mean voiding flow on voiding flowmetry examination and post-voiding residual urine (RU) were compared at 0, 1, 3, 6, and 12 months after a daily dose of 5 mg tadalafil. In addition, erectile function was evaluated by the sexual health inventory for men (SHIM) score and vessels endothelial function and peripheral neuropathy were assessed by the brachial-ankle pulse wave velocity (baPWV), ankle brachial index (ABI), and vibration perception threshold (VPT) at 0, 3, 6, and 12 months after treatment.

RESULTS

The mean age of 81 patients was 66.4 ± 11.4 years old. Their prostate size was 30.2 ± 22.1 ml. Male LUTS parameters including IPSS, OABSS, and RU showed significant improvement from 1 to 12 months after tadalafil administration. Max and mean voiding flow was significantly increased at 6 months after tadalafil treatment. The SHIM score showed significant improvement after 3 months. Whilst, the results of baPWV also showed significant improvement from 3 to 12 months. ABI was also significantly improved at 6 months. However, there was no change in the VPT at any time point.

CONCLUSIONS

Tadalafil is effective for both male LUTS and ED. It is also shown that tadalafil improves baPWV, which we can conclude that higher vessels elasticity has been obtained. This major finding of this study shows that tadalafil has the potency to improve vessels endothelial dysfunction in patients with BPH.

The Effect of Oral Phosphodiesterase-5 Inhibitors on Sperm Parameters: A Meta-analysis and Systematic Review

OBJECTIVE

To perform a systematic review and meta-analysis to evaluate the effect of phosphodiesterase-5 (PDE5) inhibitors on sperm parameters.

METHODS

A systematic literature search was performed. Mean value and its standard deviation (mean ± standard deviation) were used to perform quantitative analysis. Statistic heterogeneity scores were assessed with the standard Cochran Q test and I2 statistic. All statistical analyses were conducted by RevMan 5.3.

RESULTS

Eleven studies embraced a total of 1317 participants and 19 subgroups or trials were included. Acute administration of PDE5 inhibitors had no effect on semen volume (mean value [MD] = 0.26; 95% confidence interval [CI]: 0.00-0.48) and sperm concentration (MD = 2.04; 95%CI: -2.95 to 7.04). However, the percentage of motile spermatozoa (MD = 7.05; 95%CI: 2.59-11.51), the percentage of total progressive motility (MD = 6.23; 95%CI: 2.43-10.04), and rapid progressive motility (MD = 3.11; 95%CI: 0.23-5.99) were increased after oral PDE5 inhibitors treatment. Interestingly, these significant changes were observed only in infertile men but not in normal patients (MD = 6.89, P < .001 vs MD = 0.67, P = .71; MD = 6.64, P = .001 vs MD = 2.11, P > .05; and MD = 3.89, P = .04 vs MD = 0.92, P = .59, respectively). The percentage of morphologically normal spermatozoa also increased in infertile men (MD = 12.15; 95%CI: 5.16-19.15). Limited evidence showed the linearity, abnormal forms of spermatozoa, as well as reproductive hormones (total testosterone, free testosterone, luteinizing hormone, and follicle-stimulating hormone) did not benefit from PDE5 inhibitors treatment.

CONCLUSION

Oral PDE5 inhibitors treatment could modestly increase the sperm motility and morphology in infertile men.

PDE5 Exists in Human Neurons and is a Viable Therapeutic Target for Neurologic Disease

Phosphodiesterase 5 (PDE5) is a critical component of the cGMP-PKG axis of cellular signaling in neurons, and inhibition of PDE5 has been shown to be therapeutic in a wide range of neurologic conditions in animal models. However, enthusiasm for PDE5 inhibitors in humans is limited by data suggesting that PDE5 may not exist in human neurons. Here, we first show that past attempts to quantify PDE5 mRNA were flawed due to the use of incorrect primers, and that when correct primers are used, PDE5 mRNA is detectable in human brain tissue. We then show that PDE5 protein exists in human brain by western blot and ELISA. Most importantly, we performed immunohistochemistry and demonstrate that PDE5 is present in human neurons. We hope that this work will trigger a renewed interest in the development of PDE5 inhibitors for neurologic disease.

Pharmacodynamics, pharmacokinetics and clinical efficacy of phosphodiesterase-5 inhibitors

INTRODUCTION

Phosphodiesterase type 5 inhibitors (PDE5Is) are the first-line drugs in the management of erectile dysfunction (ED). However, over the past two decades tremendous efforts have been made to identify new clinical uses of PDE5Is beyond their roles in ED. Areas covered: Basic science articles, clinical trials, reviews, and meta-analysis published between 1996 and 2015 were searched using MEDLINE (PubMed interface) to collect the most relevant and impactful studies from our perspectives as practicing urologists. This review mainly focuses on the level one evidence-based clinical efficacy and drug-related toxicity of oral PDE5Is. In addition, drug discovery, pharmacokinetics and pharmacodynamics, potential use in other diseases, and future directions are discussed. Expert opinion: On-demand PED5Is for the treatment of ED has shifted toward chronic administration in a broad spectrum of conditions that are thought to be associated with endovascular health. Several studies have shown that PDE5Is may play a cardioprotective or neuroprotective role. Further studies are under way to verify beneficial effects of PDE5I in non-urological conditions.

Safety and efficacy of low intensity shockwave (LISW) treatment in patients with erectile dysfunction

The primary goal in the management strategy of a patient with ED would be to determine its etiology and cure it when possible, and not just to treat the symptoms alone. One of the new therapeutic strategies is the use of low intensity extracorporeal shockwave (LISW) therapy. The mechanism of shockwave therapy is not completely clear. It is suggested that LISW induces neovascularization and improvement of cavernosal arterial flow which can lead to an improvement of erectile function by releasing NO, VEGF and PCNA.

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.

SOP conservative (medical and mechanical) treatment of erectile dysfunction

INTRODUCTION

Erectile dysfunction (ED) is the most frequently treated male sexual dysfunction worldwide. ED is a chronic condition that exerts a negative impact on male self-esteem and nearly all life domains including interpersonal, family, and business relationships.

AIM

The aim of this study is to provide an updated overview on currently used and available conservative treatment options for ED with a special focus on their efficacy, tolerability, safety, merits, and limitations including the role of combination therapies for monotherapy failures.

METHODS

The methods used were PubMed and MEDLINE searches using the following keywords: ED, phosphodiesterase type 5 (PDE5) inhibitors, oral drug therapy, intracavernosal injection therapy, transurethral therapy, topical therapy, and vacuum-erection therapy/constriction devices. Additionally, expert opinions by the authors of this article are included.

RESULTS

Level 1 evidence exists that changes in sedentary lifestyle with weight loss and optimal treatment of concomitant diseases/risk factors (e.g., diabetes, hypertension, and dyslipidemia) can either improve ED or add to the efficacy of ED-specific therapies, e.g., PDE5 inhibitors. Level 1 evidence also exists that treatment of hypogonadism with total testosterone < 300 ng/dL (10.4 nmol/L) can either improve ED or add to the efficacy of PDE5 inhibitors. There is level 1 evidence regarding the efficacy and safety of the following monotherapies in a spectrum-wide range of ED populations: PDE5 inhibitors, intracavernosal injection therapy with prostaglandin E1 (PGE1, synonymous alprostadil) or vasoactive intestinal peptide (VIP)/phentolamine, and transurethral PGE1 therapy. There is level 2 evidence regarding the efficacy and safety of the following ED treatments: vacuum-erection therapy in a wide range of ED populations, oral L-arginine (3-5 g), topical PGE1 in special ED populations, intracavernosal injection therapy with papaverine/phentolamine (bimix), or papaverine/phentolamine/PGE1 (trimix) combination mixtures. There is level 3 evidence regarding the efficacy and safety of oral yohimbine in nonorganic ED. There is level 3 evidence that combination therapies of PDE5 inhibitors + either transurethral or intracavernosal injection therapy generate better efficacy rates than either monotherapy alone. There is level 4 evidence showing enhanced efficacy with the combination of vacuum-erection therapy + either PDE5 inhibitor or transurethral PGE1 or intracavernosal injection therapy. There is level 5 evidence (expert opinion) that combination therapy of PDE5 inhibitors + L-arginine or daily dosing of tadalafil + short-acting PDE5 inhibitors pro re nata may rescue PDE5 inhibitor monotherapy failures. There is level 5 evidence (expert opinion) that adding either PDE5 inhibitors or transurethral PGE1 may improve outcome of penile prosthetic surgery regarding soft (cold) glans syndrome. There is level 5 evidence (expert opinion) that the combination of PDE5 inhibitors and dapoxetine is effective and safe in patients suffering from both ED and premature ejaculation.

An update on pharmacological treatment of erectile dysfunction with phosphodiesterase type 5 inhibitors

INTRODUCTION

Phosphodiesterase type 5 inhibitors (PDE5-i) are used for the oral treatment of erectile dysfunction (ED). Since the launch of sildenafil more than 15 years ago, new molecules have become available. At present, in addition to tadalafil and vardenafil, there are three other drugs, udenafil, avanafil and mirodenafil, marketed in some countries which appear to be promising.

AREAS COVERED

The clinical pharmacological differences in dosage and side effects of all PDE5-i are evaluated.

EXPERT OPINION

All PDE5-i are equally effective and safe for the treatment of ED. On-demand use of any PDE5-i is also safe for patients with comorbid conditions. Tadalafil seems to be the preferred drug by patients and physicians, probably due to its peculiar pharmacological profile that makes sexual intercourse more spontaneous for the patients. Preliminary data suggest that the use of vardenafil may also be beneficial in cases of ED associated with premature ejaculation. Daily treatment is another option in men with ED and documented vascular or prostate disease. In geriatric or in difficult-to-treat populations, the evaluation of testosterone plasma levels will help to predict the efficacy of any PDE5-i. Remarkably, when such drugs are withdrawn for any reason, ED most often continues to occur because of the presence of an underlying disease.

A case of acute pulmonary thromboembolism after taking tadalafil

Tadalafil is a phosphodiesterase-5 inhibitor (PDE5I), which is widely used to treat erectile dysfunction. Although PDE5Is have excellent safety profiles, and most of the side effects are mild, rare serious adverse events have been reported in association with PDE5Is. Thrombosis is one of those events, and a few previous reports have suggested the association of PDE5Is with thrombosis. We report the case of a 61-year-old male who developed pulmonary embolism combined with pulmonary infarction directly after taking tadalafil. Both the patient and the physician suspected tadalafil as the culprit drug, as the patient was in an otherwise healthy condition. However, after extensive evaluation, we noticed that factor VIII levels were elevated. Prior reports suggesting the association between thrombosis and PDEIs either lack complete information on coagulation factors, or show inconsistencies in their results. Physicians should operate caution prior to accepting the diagnosis of adverse drug reaction.

Efficacy and safety of once-daily tadalafil in men with erectile dysfunction who reported no successful intercourse attempts at baseline

INTRODUCTION

Tadalafil is efficacious and well tolerated for erectile dysfunction (ED), but effects in men with "complete ED" are unclear.

AIM

To investigate effects of once-daily tadalafil in men with no successful intercourse attempts at baseline.

METHODS

Through a post hoc, pooled-data analysis of four randomized, double-blind trials on the effects of tadalafil 2.5 or 5 mg (vs. placebo) in men with ED, we evaluated efficacy and safety in subjects with 0 "yes" responses to Sexual Encounter Profile question 3 (SEP3) during an initial 4-week treatment-free run-in period.

MAIN OUTCOME MEASURES

Changes from baseline in the SEP diary and the International Index of Erectile Function-erectile function (IIEF-EF) domain were subjected to analysis of covariance models.

RESULTS

Five hundred ninety-five subjects with no successful attempts at baseline were included in the analysis. The mean (± standard deviation) age was 58.2 ± 10.7 years; and most subjects had ED for ≥ 1 year (95.0%). ED was severe in 61.5% and moderate in 26.4%. Approximately 45% had diabetes mellitus or hypertension. After 12 weeks, the mean per-patient SEP3 percentage increased from 0% to 32.4% with tadalafil 2.5 mg and to 46.4% with tadalafil 5 mg (each P < 0.001 vs. placebo). Corresponding data for successful penetration (SEP2) were increases from 21.1% to 48.2% with tadalafil 2.5 mg and from 24.4% to 66.2% with 5 mg (each P < 0.001 vs. placebo). Mean IIEF-EF increased from 9.7 to 15.7 with tadalafil 2.5 mg and from 10.7 to 19.2 with 5 mg (each P < 0.001 vs. placebo). Tadalafil also significantly improved the intercourse-satisfaction and overall-satisfaction domains (vs. placebo). Both doses of tadalafil were generally well tolerated, with adverse event rates similar to placebo.

CONCLUSIONS

The posttreatment intercourse success rate was 32% and 46% for tadalafil 2.5 mg and 5 mg, respectively, in men with no successful intercourse attempts at baseline.

Tadalafil for the Treatment of Lower Urinary Tract Symptoms in Japanese Men with Benign Prostatic Hyperplasia: Results from a 12-week Placebo-controlled Dose-finding Study with a 42-week Open-label Extension

OBJECTIVES

To examine the efficacy, safety, and dose response of tadalafil once daily in Japanese men with lower urinary tract symptoms suggestive of benign prostatic hyperplasia (BPH-LUTS).

METHODS

Men ≥45 years with moderate-to-severe BPH-LUTS were randomized to once-daily placebo (N = 140), tadalafil 2.5 mg (N = 142), or tadalafil 5.0 mg (N = 140), in a 12-week double-blind phase, followed by a 42-week, tadalafil 5.0 mg open-label extension (OLE) phase (N = 394). The primary outcome was total International Prostate Symptom Score (IPSS) change from baseline to last available observation in the double-blind phase.

RESULTS

The least squares (LS) mean difference between placebo and tadalafil in total IPSS change from baseline was -0.7 (P = 0.201) and -1.1 (P = 0.062) for tadalafil 2.5 and 5 mg, respectively (ANCOVA; a dose-dependent improvement in placebo-adjusted total IPSS for tadalafil 5 mg versus 2.5 mg of 57%). Repeated-measures analyses identified a significant total IPSS change for tadalafil 5 mg (LS mean difference between placebo and tadalafil 5 mg: -1.2; P = 0.035), but not tadalafil 2.5 mg, at week 12. Significant improvements for tadalafil 5 mg were demonstrated (ANCOVA) for IPSS obstructive subscore (P = 0.033) and IPSS quality of life index (P = 0.022). Numerical improvements in IPSS scores were maintained over the OLE phase. Tadalafil was well tolerated with no unexpected adverse events.

CONCLUSION

Tadalafil (5.0 mg) had a favorable benefit-to-risk profile, supporting further investigation of tadalafil (5.0 mg) in Japanese men with BPH-LUTS.

Tadalafil once daily in the management of erectile dysfunction: patient and partner perspectives

Erectile dysfunction (ED) is a prevalent condition that affects men and their partners. Significant improvements in the sexual lives of these couples have been achieved with the introduction of phosphodiesterase 5 (PDE5) inhibitors. A PDE5 inhibitor is now widely recognized as the first-line therapy for the majority of men with ED. Currently, three PDE5 inhibitors - sildenafil, tadalafil and vardenafil - are approved to be taken as needed in anticipation of sexual activity, but only one of these, tadalafil, has been approved to be taken once daily. The primary aims of this review are to summarize the patients' and partners' viewpoints of ED management with PDE5 inhibitors, and to determine whether once-daily tadalafil can contribute to improving some psychological aspects of ED (such as sexual self-confidence, spontaneity and time concerns) compared with on-demand tadalafil or other PDE5 inhibitors taken by patients with ED.