Tadalafil for lower urinary tract symptoms secondary to benign prostatic hyperplasia: a review of clinical data in Asian men and an update on the mechanism of action

Utilization of absorbance subtraction and ratio difference green spectrophotometric methods for the quantification of alfuzosin hydrochloride and tadalafil in their binary mixture

Alfuzosin hydrochloride and tadalafil fixed-dose combination tablets were recently formulated for the treatment of individuals with lower urinary tract symptoms caused by benign prostatic hyperplasia. Herein, the first spectrophotometric methods for quantitative analysis of alfuzosin hydrochloride and tadalafil in their binary mixture were established. The spectral overlapping of alfuzosin hydrochloride and tadalafil made direct simultaneous analysis unfeasible. Therefore, two mathematical methods were used to solve these overlapping spectra: absorbance subtraction and ratio difference. The absorbance subtraction method manipulates the zero absorption spectra of the studied drugs at the isoabsorptive point (272 nm) and uses the absorbance factor of pure ALF to calculate the absorbance of the studied drugs in the mixture at the isoabsorptive point. The ratio spectra method, on the other hand, manipulates the ratio spectra of the studied drugs, which are obtained by dividing each drug's zero absorption spectra by a divisor spectrum from the second drug. The ratio amplitude difference between 251 nm and 211 nm was directly proportional to alfuzosin hydrochloride, whereas between 292 nm and 222 nm it was directly proportional to tadalafil. The methods used were verified in accordance with the recommendations of the ICH and demonstrated adequate linear regression in working ranges of 1-15 µg/mL for alfuzosin hydrochloride and 3-40 µg/mL for tadalafil. The methods were accurate, precise, and selectively employed to quantify alfuzosin hydrochloride and tadalafil in their combined tablets.

Sauna habits/bathing and changes in lower urinary tract symptoms - Tampere Ageing Male Urologic Study (TAMUS)

OBJECTIVE

To evaluate the effect of sauna bathing on lower urinary tract symptoms (LUTS) in a Finnish population-based cohort.

METHODS

A mail survey was sent to a population-based cohort of 50-, 60-, and 70-year-old men in 1994 followed by repeat questionnaires in 1999 and 2004. The evaluation of ten different types of LUTS was based on Danish Prostatic Symptom Score (DAN-PSS-1). The weekly frequency of sauna bathing was assessed in the first questionnaire and divided into three subgroups (0-1, 2, and ≥3). The prevalence, incidence, and remission rate of each LUTS was assessed based on the initial and follow-up assessments. In addition, the mean DAN-PSS-1 symptoms score, medication for LUTS, and operative treatment were determined at each time-point. Chi-square test, a linear-by-linear test, and binary logistic regression analysis were used to assess statistical significance.

RESULTS

The population-based cohort included initially 3,163, men of whom 1,306 (41.3%) responded to all three questionnaire rounds and were included in the analysis. There was no clear association between sauna bathing frequency and prevalence of the nine LUTS, nor with incidence and remission rates. The only exception was feelings of incomplete emptying, with lower prevalence associated with frequent sauna bathing. There were no clear differences in the medications or operations for LUTS by sauna bathing habits.

CONCLUSION

Based on our results, sauna bathing does not affect LUTS development or natural history in the long-term.

Efficacy of testosterone replacement therapy plus alternate-day tadalafil for patients with late-onset hypogonadism: An open-label, randomized, crossover study

OBJECTIVE

To examine the efficacy and safety of combination treatment with testosterone replacement therapy plus alternate-day tadalafil (10 mg) in patients with late-onset hypogonadism.

METHODS

In this open-label, randomized, crossover study, 29 patients with late-onset hypogonadism were randomly assigned to receive testosterone replacement therapy for 12 weeks followed by combination treatment for 12 weeks (Group 1) or combination treatment for 12 weeks followed by testosterone replacement therapy (Group 2). Symptom questionnaires were administered and blood tests were performed prior to and following each treatment to assess safety and efficacy. At the end of the study, participants were asked about their treatment preferences.

RESULTS

An adverse effect, a rheum symptom, occurred in only one participant, and 26 participants completed the study without any toxicity. Scores on the Aging Male Symptoms scale and the modified short version of the International Index of Erectile Function, and Overactive Bladder Symptom scores were significantly improved in the combination treatment phase of Group 2, whereas no significant difference between the phases were observed in Group 1. In total, 12 out of the 14 participants in Group 1 and 11 out of the 12 participants in Group 2 preferred combination treatment, which reached statistical significance (P = 0.008 and 0.004 for Groups 1 and 2, respectively).

CONCLUSIONS

Testosterone replacement therapy with add-on alternate-day tadalafil is a safe and satisfactory treatment for patients with late-onset hypogonadism.

Real-World Safety and Effectiveness of Tadalafil in Patients with Lower Urinary Tract Symptoms Secondary to Benign Prostatic Hyperplasia: A Japanese Post-Marketing Surveillance Study

Objective

To evaluate the long-term safety and effectiveness of tadalafil in Japanese men with lower urinary tract symptoms secondary to benign prostatic hyperplasia in real-world clinical practice; and to investigate the safety profile in patients aged ≥75 years.

Patients and Methods

This was a prospective, non-interventional, multicenter, post-marketing surveillance study in which Japanese patients with lower urinary tract symptoms secondary to benign prostatic hyperplasia were observed for up to 18 months after initiating tadalafil treatment. The real-world safety and effectiveness outcomes were assessed at baseline and at 1, 3, 6, 12, and 18 months post-treatment or the last day of treatment.

Results

Most patients received tadalafil 5 mg per day throughout the observation period. Among 1393 patients analyzed for safety, the overall incidence of adverse drug reactions was 8.3%. These adverse drug reactions were generally consistent with the known safety profile of tadalafil and no new safety risks were identified in long-term use. There was no statistical difference in the frequency of adverse drug reactions between patients aged <75 and ≥75 years. The mean change in total International Prostate Symptom Score (IPSS) and IPSS-quality of life subscore was significantly improved at each timepoint. At 18 months, IPSS had improved by 5.0 points (P < 0.001) and IPSS-quality of life subscore had improved by 1.5 points (P < 0.001). The mean change in post-voiding residual urine volume from baseline was significant at each time point and was −9.8 mL at 18 months (P < 0.001); there were no significant differences from baseline in maximum urinary flow rate.

Conclusion

This surveillance demonstrated that tadalafil has favorable safety and effectiveness profiles for long-term use in Japanese men with lower urinary tract symptoms secondary to benign prostatic hyperplasia. In addition, safety profiles in patients aged ≥75 years were similar to patients aged <75 years.

Defining the Efficacy and Safety of Phosphodiesterase Type 5 Inhibitors with Tamsulosin for the Treatment of Lower Urinary Tract Symptoms Secondary to Benign Prostatic Hyperplasia with or without Erectile Dysfunction: A Network Meta-Analysis

Purpose

The purpose of this study was to compare the relative safety and efficacy of different types of phosphodiesterase type 5 inhibitors (PDE5-Is) with tamsulosin for the treatment of lower urinary tract symptoms (LUTS) secondary to benign prostate hyperplasia (BPH) (BPH-LUTS) with or without erectile dysfunction (ED).

Methods

We use the Stata version 13.0 to conduct the network meta-analysis (NMA) with a random effects model of the Bayesian framework. The International Prostate Symptom Score (IPSS), Maximum Urinary Flow Fate (Q_max), International Index of Erectile Function (IIEF), and their credible intervals (CI) were used to compare the efficacy and safety of every medical intervention, including sildenafil plus tamsulosin, tadalafil plus tamsulosin, and vardenafil plus tamsulosin.

Results

Seven RCTs including 531 participants with seven interventions were analyzed. The results of NMA SUCRA showed that compared with different doses or types of PDE5-Is combined with tamsulosin (0.4 mg qd), the sildenafil (25 mg qd) combined with tamsulosin (0.4 mg qd) group had the greatest probabilities of being the best in the achievement of improving IIEF. The sildenafil (25 mg 4 days per week) combined with tamsulosin (0.4 mg qd) group had the greatest probabilities of being the best in the achievement of improving Q_max, whereas sildenafil (25 mg qd) combined with tamsulosin (0.4 mg qd) ranked the best for the safety outcomes.

Conclusions

This meta-analysis indicates that sildenafil combined with tamsulosin is the best effective and tolerated treatment option for BPH-LUTS with or without ED. Further RCTs are strongly required to provide more direct evidence.

Self-Care and Quality of Life in Elderly Chinese Patients with Benign Prostatic Hyperplasia

The authors in this study explored the relationship between self-care agency and quality of life in patients with benign prostatic hyperplasia. A convenience sample of 157 patients was interviewed. The levels of both self-care agency and quality of life were close to the mean. Pearson correlation analysis demonstrated that quality of life was positively correlated with self-care agency and the self-care subgroups of abilities, responsibility, esteem, and evaluation. Improved self-care agency and the four subscale items could enhance quality of life. Intervention programs for benign prostatic hyperplasia patients must emphasize self-care agency so as to improve their health behavior and quality of life.

Treatment of experimentally induced benign prostatic hyperplasia with Tadalafil and castration in dogs

New methods are being developed for the treatment of benign prostatic hyperplasia (BPH) in dogs. The aim of the present study was to evaluate the effects of Tadalafil on the treatment of experimentally induced BPH in dogs. Twenty-five adult intact male dogs were randomly divided into five groups (n = 5): normal group; dogs induced with BPH and treated with Tadalafil (5 mg/day p.o.); dogs which received Tadalafil (5 mg/day p.o.); dogs induced with BPH and treated with castration; and dogs induced with BPH. For 4 sequential weeks, the hematologic and prostate-specific factors (dihydrotestosterone (DHT), serum prostate-specific antigen (PSA), serum prostatic acid phosphatase (PAP), and canine prostatic specific esterase (CPSE)) were measured. Significant differences were observed in the level of PSA, CPSE, and PAP concentration between the normal vs. BPH-Tadalafil, BPH-castrated, and BPH groups. Treating BPH-induced dogs with Tadalafil or castration significantly declined the serum PSA, CPSE, and PAP levels compared to those of the untreated BPH-induced group. The treatment of normal dogs with Tadalafil did not affect prostate-specific biomarkers in comparison with normal dogs. In conclusion, and according to the prostatic indices, it could be stated that Tadalafil, compared with castration, could be used for the treatment of BPH in dogs.

Phosphodiesterase type 5 inhibitor attenuates chronic ischemia-induced prostatic hyperplasia in a rat model

BACKGROUND

Many elderly men suffer from benign prostatic hyperplasia (BPH). Recently, chronic ischemia in the prostate has been suggested to be related to BPH. Thus, the impact of chronic ischemia on the development of prostatic hyperplasia and the efficacy of phosphodiesterase type 5 (PDE5) inhibitor for hyperplasia were evaluated in a rat model with chronic ischemia induced by local atherosclerosis.

METHODS

Eighteen male Sprague-Dawley rats were divided into three groups: sham operation, regular diet, placebo (SRP); arterial endothelial injury, high cholesterol diet, placebo (AHP); or arterial endothelial injury, high cholesterol diet, and tadalafil as a PDE5 inhibitor (AHT). The endothelial injury in the common iliac arteries was performed using a 2-Fr Fogarty arterial embolectomy catheter through an incision in the femoral artery into the common iliac artery. Diet and oral drugs were administrated for 8 weeks after surgery. At 8 weeks, blood flow to the ventral prostate (VP) was measured using laser speckle blood flow analysis, and the VP was histologically evaluated.

RESULTS

In the AHP group, prostatic blood flow was reduced, and mean VP weight and the interstitial area were significantly enlarged compared with the SRP group. In the AHT group, tadalafil administration obviously ameliorated the reduction of prostatic blood flow relative to the AHP group. Importantly, mean VP weight and the morphological changes in the AHT group were significantly smaller than those in the AHP group.

CONCLUSIONS

Enlargement of the VP resulted from chronic ischemia induced by local arteriosclerosis. Also, administration of tadalafil attenuated VP enlargement. Chronic ischemia in the prostate might thus contribute to the development of BPH, and PDE5 inhibitors might provide an innovative approach to preventing BPH.

Effects of a combination of herbal extracts (modified Ojayeonjonghwan (Wuzi Yanzong wan)) on partial urethral obstruction-induced detrusor overactivity in rats: impact on the nitric oxide pathway and oxidative stress

Background

We investigated the effects of a berry mixture formula (modified Ojayeonjonghwan (Wuzi Yanzong Wan, MO formula) on detrusor overactivity (DO).

Methods

The MO formula consisted of 5 seeds obtained from 5 types of berry plants. Twenty-four Sprague-Dawley rats were randomly assigned to four groups: sham-operated (control), partial urethral obstruction-induced DO (DO group), 0.03 mg/kg solifenacin-treated DO (solifenacin group) and 200 mg/kg MO formula -treated DO (berry mixture). The control and overactive groups were administered distilled water for 4 weeks, and the solifenacin and MO formula groups were treated with the respective medication for 4 weeks. After treatment, cystometrography was performed. At the endo of cystometrography, their bladder tissues were used for identifying the muscarinic receptors, endothelial nitric oxide synthase(eNOS), RhoA, Rock-I & II, 8-hydroxy-2′ –deoxyguanosine(8-OHdG), superoxide dismutase(SOD), interleukin-6 &-8(IL-6, IL-8), and tumor necrosis factor-alpha(TNF-a). The tissues were stained and the muscle-to-collagen ratio was identified.

Results

The presence of the muscarinic receptors were not significantly different between the solifenacin and MO formula groups. However, significant differences were found between the solifenacin and MO formula groups in terms of eNOS, RhoA, Rock-I and -II levels. The muscle-to-collagen ratio was statistically lower in the DO and solifenacin groups; however, no significant difference was observed between the control and MO formula groups. Under oxidative stress, SOD showed a similar result as 8-OHgG. The MO formula group exhibited anti-inflammatory effects, showing that no significant difference was found between the control and MO formula groups regarding values of IL-6, IL-8, and TNF-a. However, the DO and solifenacin groups showed increased IL-6, IL-8, and TNF-a levels. Cystometrography showed that the OAB and solifenacin groups having a significantly lower value than the control and MO formula groups. The mean contraction interval was shorter in the DO, MO formula, and solifenacin groups and the highest in the control group.

Conclusions

The MO formula exhibited a similar pharmacologic effect to that of solifenacin, with anti-inflammatory and antioxidant effects. Enhancement of the MO formula by the nitric oxide pathway affected DO including BPH-related DO. The MO formula may be one of the alternative choices of anticholinergics, a treatment for DO.

Links between lower urinary tract symptoms, intermittent hypoxia and diabetes: Causes or cures?

Bothersome lower urinary tract symptoms (LUTS) manifest as urinary frequency, urgency, incontinence and incomplete bladder emptying. Existing treatments ameliorate but do not eliminate most symptoms, leading to financial and personal burdens attributable to sustained medical therapies that may last a lifetime. The purpose of this review is to highlight evidence of causal associations between LUTS and several common comorbidities, including intermittent hypoxia (IH) concomitant with obstructive sleep apnea (OSA), obesity, metabolic syndrome and type 2 diabetes. Links between these conditions, including therapies targeted to co-occurring complications that have demonstrated benefits for LUTS, suggest compelling avenues of research and also underscore critical gaps in understanding the mechanisms underlying urinary dysfunction. These gaps are prominent in the IH field, where an acknowledged link between OSA and LUTS has gone largely uninvestigated. New tools, models, or reappropriation of existing ones, especially rodent models, is required to parse the associations between IH/OSA, LUTS and obesity/diabetes and to elucidate their underlying, and potentially shared, etiologies.

Alpha-blockers with or without phosphodiesterase type 5 inhibitor for treatment of lower urinary tract symptoms secondary to benign prostatic hyperplasia: a systematic review and meta-analysis

PURPOSE

Recently, several randomized controlled trials (RCTs) explored the effects of α-blockers with or without phosphodiesterase type 5 inhibitors (PDE5-Is) for lower urinary tract symptoms secondary to benign prostatic hyperplasia (LUTS/BPH). However, the results were inconsistent. We performed this meta-analysis to evaluate the role of combination therapy (α-blockers and PDE5-Is) in patients with LUTS/BPH.

MATERIALS AND METHODS

Databases including PubMed, Cochrane library, Web of Science, and Embase were searched for qualified RCTs. Pooled mean differences (MDs) and odds ratios (ORs) were calculated to measure the effects and adverse events in combination therapy. Moreover, subgroup analyses of ethnicity, dosage of PDE5-Is, treatment duration, and severity of LUTS/BPH were performed. In addition, trial sequential analyses (TSAs) were used to assess whether the evidence for the results was sufficient.

RESULTS

Overall, this study identified 11 eligible RCTs, including 855 LUTS/BPH patients. Patients receiving combination therapy had better improvement in international prostate symptom score (IPSS: MD: 1.66, 95% CI - 3.03 to - 0.29), maximum urinary flow rate (Q_max: MD: 0.94, 95% CI 0.24-1.64), and international index of erectile function (IIEF: MD: 4.73, 95% CI 2.95-6.51), comparing those without PDE5-Is. Besides, subgroup analyses indicated that the effects of combination treatment were associated with ethnicity, treatment duration, and severity of LUTS/BPH. By TSA, the findings in the current study were based on sufficient evidence.

CONCLUSIONS

Our results indicated that combination therapy can significantly improve IPSS, Q_max, and IIEF in patients with LUTS/BPH. Combination therapy might be more suitable for these patients.

Low dose daily versus on-demand high dose tadalafil in diabetic patients with erectile and ejaculatory dysfunction

The aim was to compare the differences between daily 5 mg and on-demand 20 mg tadalafil use in diabetic patients with erectile dysfunction (ED), and the effects of two different tadalafil protocols on ejaculatory and lower urinary tract symptoms (LUTS). Of the 63 diabetic patients with ED, 31 were given 5 mg tadalafil once a day, and 32 were given 20 mg tadalafil on-demand four times a month over three months. Erectile function, erectile hardness, ejaculatory function, and LUTS were assessed at pretreatment, first- and third-month controls. Both tadalafil protocols increased International Index of Erectile Function (IIEF) scores in all patients under 65 years, whereas patients older than 65 years did not benefit. Ejaculatory function, the quality of the hardness of an erection, and LUTS improved in both groups in the study. Tadalafil improved sexual function with acceptable side effects in diabetic men with ED. Both protocols equally improved LUTS and the quality of the erection. Daily use of 5 mg of tadalafil significantly improved the quality of ejaculation and LUTS more than the on-demand use of 20 mg of tadalafil. It may be beneficial to give 5 mg tadalafil daily to patients over 65 years old who do not benefit from treatment with 20 mg of tadalafil or in patients who have LUTS over 65 years old.

Safety and Effectiveness of Once-Daily Tadalafil (5 mg) Therapy in Korean Men with Benign Prostatic Hyperplasia/Lower Urinary Tract Symptoms in a Real-World Clinical Setting: Results from a Post-Marketing Surveillance Study

Purpose

The aim of this study was to investigate the safety and effectiveness of tadalafil 5 mg once daily (quaque die [everyday], QD) among Korean men with benign prostatic hyperplasia (BPH)/lower urinary tract symptoms (LUTS) in a real-world clinical setting.

Materials and Methods

This was a single-country, prospective, observational cohort study in which patients newly prescribed tadalafil 5 mg QD for the treatment of BPH/LUTS were followed-up for 12±2 or 24±2 weeks, or to the last treatment, during post-marketing surveillance. Safety was evaluated in terms of the frequency of treatment-emergent adverse events (TEAEs) and serious adverse events (SAEs). Effectiveness was assessed by changes in the International Prostate Symptom Score (IPSS) from baseline to each endpoint.

Results

All patients receiving ≥1 dose of tadalafil 5 mg QD (N=637) were included in the safety population. Two percent of patients (n=13) experienced 15 TEAEs of mild (n=10; 66.7%) or moderate (n=5; 33.3%) severity. No severe TEAEs and no SAEs were reported. Effectiveness evaluations included all patients receiving tadalafil who had both baseline and endpoint observations (12-week, N=265; 24-week, N=44). Compared with baseline, the mean IPSS total score (±standard error) significantly improved by 4.7±0.3 and 6.4±0.7 points at the 12- and 24-week endpoints, respectively (p<0.0001), with significant improvements also observed on the storage, voiding, and quality of life subscores. In total, 69.1% of the patients had a clinically meaningful ≥3-point improvement in the IPSS total score.

Conclusions

Tadalafil 5 mg QD was well tolerated and effective in Korean men with BPH/LUTS in a real-world clinical setting.

The impact and management of sexual dysfunction secondary to pharmacological therapy of benign prostatic hyperplasia

Benign prostatic hyperplasia (BPH) is one of the most common genitourinary complications in men over 50 years of age and typically presents with lower urinary tract symptoms (LUTS). Classes of medications include α1-adrenoceptor blockers, 5α-reductase inhibitors, and phosphodiesterase 5 inhibitors. Today, α1-adrenoceptor blockers and 5α-reductase inhibitors are often combined to give a synergistic effect. A review of the current literature identified several adverse sexual side effects, including erectile dysfunction (ED), decreased libido, orgasmic disorders, and ejaculatory disorders. We believe it is important to know the extent of these side effects, as the clinician and patient will need to decide the cost of improved voiding symptoms. The chief adverse effect is ejaculatory disorders, including the absence of ejaculation. Clinical consideration for BPH should include the elements of male sexual function, patients’ age, and the characteristics and comprehensive effects of each group of drugs. Methodological bias in clinical studies, such as the subjective evaluation of the sexual side effect, makes it difficult to determine the ideal drug for treatment.

Is there room for behavioral and modifiable health-related targets in the lower urinary tract symptoms' scenario

PURPOSE

To better understand potential modifiable risk factors guiding preventive interventions against lower urinary tract symptoms (LUTS).

METHODS

A prospective cross-sectional study, including healthy men aged 40-70 years under routine urological evaluation, measured the strength of association between the International Prostate Symptom Score (IPSS) and socio-demographic, lifestyle, and health-related factors using logistic and linear regression adjusted for confounding factors. Men with urethral or prostate surgery were excluded.

RESULTS

Among 743 men, mean age 59.64 ± 9.66, 22.6% reported moderate, and 5.0% severe LUTS. The adjusted odds of severe LUTS increased with: increasing age (OR = 1.07, 95% CI = 1.05-1.09, p < .0001), increasing prostate volume (OR = 1.02, 95% CI = 1.01-1.04, p = .004), decreasing education (tertiary qualification, no versus yes, OR = 2.34; 95% CI = 1.16-4.70; p = .0133), delayed ejaculation (yes versus no, OR = 2.63, 95% CI = 1.43-4.83, p < .0001), and increasing blood pressure (systolic ≥130 mmHg, OR = 2.03, 95% CI = 1.44-2.86, p < .0001 or diastolic ≥85 mmHg, OR = 1.47, 95% CI = 1.03-2.10, p = .0345); severe LUTS decreased with: increasing the weekly sexual frequency (OR = 0.80, 95% CI = 0.69-0.91, p = .0012) and increasing HDL cholesterol (OR = 0.98, 95% CI = 0.97-0.99, p = .037). Odds were not significant for age of sexual initiation, precocious ejaculation, masturbatory pattern, physical activity, smoking, alcohol consumption, penile length (objective and subjective), abdominal circumference, obesity, comorbid conditions, metabolic syndrome, serum glycaemia, testosterone, SHBG, PSA, and estradiol.

CONCLUSIONS

One in every four men under routine urological evaluation who considered themselves healthy present moderate and severe LUTS. Modifiable behavioral (education, sexual frequency, and ejaculation) and health-related (blood pressure and HDL cholesterol) targets were identified for future interventional studies and potential preventive actions and patient counseling.