A cost-utility analysis of phosphodiesterase type 5 inhibitors in the treatment of erectile dysfunction

A Cost Analysis of Phosphodiesterase Type 5 Inhibitors in the United States

OBJECTIVE

To perform a cost analysis of generic and brand-name Phosphodiesterase Type 5 (PDE5) inhibitors at different dosages and pharmacies across the US.

METHODS

Using an all-payer retail pharmacy-claims database, we analyzed prescription drug data for three generic and six brand-name oral PDE5 inhibitors at different dosages across US chain and independent pharmacies in 2019.

RESULTS

We obtained cash price data from 60,186 pharmacies (35,976 chain and 24,210 independent). The nationwide mean cash price per unit (PPU) ranged from $8.6 ± 5.2 (sildenafil 20 mg at chain pharmacies) to $107.1 ± 71 (Adcirca 20 mg at independent pharmacies) equal to 1145.3% difference. Chain pharmacies provided significantly lower average prices for one brand-name and six generic PDE5 inhibitors. Tadalafil PPU was cheaper at higher quantities, however, PPU increased with quantity prescribed for sildenafil. Looking at the top 10 metropolitan statistical areas, the highest PPUs were observed for tadalafil (Cialis) 10 mg and sildenafil (Viagra) 50 mg in Atlanta ($67.4 ± 8.7) and Los Angeles ($50.3 ± 24.0), while New York ($9.7 ± 2.6) and Miami ($27.9 ± 16.4) had the lowest PPUs for tadalafil (Cialis) 5 mg and sildenafil (Viagra) 100 mg, respectively.

CONCLUSION

A substantial variability in PDE5 inhibitor cash prices exists across manufacturer, dosage, quantity, pharmacy type, and location. In addition, the pricing does not necessarily correlate with the regional socioeconomic factors. This highlights the importance of provider awareness and patient counseling on drug price including potentially assisting patients in identifying opportunities for cost savings.

Predictors of Phosphodiesterase Type 5 Inhibitor Treatment Failure in Patients Diagnosed With Erectile Dysfunction

INTRODUCTION

Erectile dysfunction (ED) is a prevalent condition, especially in aging populations, with significant implications for quality of life. While phosphodiesterase type 5 inhibitors (PDE5Is) are the first-line treatment, a substantial percentage of patients do not respond satisfactorily. This study aimed to identify predictors of PDE5I treatment failure in ED patients.

METHODS

Data from January 2016 to January 2022 was reviewed for patients with ED who either failed PDE5I treatment or had a successful outcome. Demographic, medical, and laboratory data were collected and analyzed. Patients with contraindications or who did not complete the treatment were excluded.

RESULTS

The treatment failure group comprised 288 patients, while 225 age-matched patients formed the control responder group. There were no significant differences in marriage duration, comorbidities, smoking, or BMI. However, HbA1c levels, free testosterone, and SHBG were significantly different between the two groups.

CONCLUSION

This study found that high HbA1c levels, low free testosterone, and high sex hormone-binding globulin (SHBG) were associated with PDE5I treatment failure. Managing high HbA1c levels and addressing hormonal imbalances may enhance PDE5I treatment effectiveness in ED patients. However, further research is needed to explore other factors contributing to treatment outcomes.

A Review of Combined Phosphodiesterase-5-Inhibitors and α-Blockers versus Phosphodiesterase-5-Inhibitors Alone for Lower Urinary Tract Symptoms due to Benign Prostatic Hyperplasia

Guidelines from the American Urological Association (AUA) and the European Association of Urology (EAU) present conflicting recommendations regarding combination therapy of phosphodiesterase 5 inhibitors (PDE5is) with α-blockers to treat benign prostatic hyperplasia (BPH) with lower urinary tract symptoms (LUTS). Use of PDE5is is widespread in the population of patients with LUTS/BPH. In this scoping review, we examine the evidence regarding the safety and efficacy of combined PDE5is and α-blockers compared to PDE5i medications alone. A search was conducted using PubMed, Cochrane, and Web of Science to identify manuscripts discussing the safety of PDE5i and α-blockers in combination or comparing this combination to PDE5is alone in the treatment of LUTS/BPH. Study designs, data, and conclusions were qualitatively analyzed. Combination therapy was found to be safe across all studies; importantly, no evidence documents increased risk of hypotension. Most studies reported added improvement in symptom and quality of life scores compared to PDE5i alone, with additional International Prostate Symptom Score (IPSS) change ranging from -1.30 to -8.50 and IPSS quality of life score change ranging from -0.15 to -1.50. Objective metrics such as postvoid residual volumes and maximum flow rate were inconsistently reported. Taken together, the current body of data suggests that combining PDE5i α-blocker therapy is safe and that there are opportunities for additional symptomatic improvement, though it should be utilized for select patients. Situations with particular utility could include patients with comorbid erectile dysfunction or without sufficient improvement on monotherapy.

Long-term high-dose L-arginine supplementation in patients with vasculogenic erectile dysfunction: a multicentre, double-blind, randomized, placebo-controlled clinical trial

PURPOSE

The current randomized, double-blind, placebo-controlled clinical trial addressed the effects on penile erectile function of relatively high daily oral doses (6 g/day) of L-ARG for 3 months (N = 51) compared to placebo (N = 47), in patients with vasculogenic ED, with comparison between mild-moderate and severe vasculogenic ED.

METHODS

The outcome measures included IIEF-6 score and cavernous arteries peak systolic flow velocity (PSV) at dynamic penile duplex ultrasonography (PDU).

RESULTS

L-ARG supplementation for 3 months significantly increased IIEF-6 score in the overall cohort (p < 0.0001) and in subgroups of patients with mild-moderate (p < 0.0001) and severe (p = 0.007) vasculogenic ED; PSV was significantly increased in the overall cohort (p < 0.0001) and in patients with mild-moderate (p < 0.0001), but not severe vasculogenic ED. At study completion, 74% of patients improved ED degree category, although only 24% of patients, mainly belonging to the baseline category of mild ED, reached IIEF-6 scores compatible with absence of ED; moreover, 20% of patients, exclusively belonging to the baseline category of mild-moderate vasculogenic ED, reached PSV values compatible with absence of ED.

CONCLUSION

The results of the current study demonstrated that supplementation with relatively high doses of L-ARG as a single compound for 3 months significantly improved penile erectile function, assessed by both IIEF-6 score and PSV at dynamic PDU in patients with mild-moderate, and improved IIEF-6 score, but not PSV, in patients with severe vasculogenic ED, therefore suggesting that L-ARG might be an alternative treatment in mild-moderate vasculogenic ED patients experiencing adverse effects or with contraindications for chronic treatment with PDE5i compounds.

Erectile dysfunction treatment with Phosphodiesterase-5 Inhibitors: Google trends analysis of last 10 years and COVID-19 pandemic

OBJECTIVES

We aimed to analyze the trend change of the most popular Phosphodiesterase-5 Inhibitors (PDE5i) over time and geography by using Google Trends (GT) data in 10 years period and COVID-19 pandemic.

MATERIALS AND METHODS

GT is able to generate a "line-graph", showing how interest has increased or decreased over a period within specific territories. The search values for specific terms are indexed as relative search volume (RSV), which is presented on a scale from 0-100. Avarage annual percentage change (AAPC) and RSV were analyzed to evaluate gain or loss of interest in trends. Search terms were generated for Food and Drug Administration (FDA)-approved PDE5i; tadalafil, sildenafil, vardenafil, avanafil, and their most-used brand names. The data was within "worldwide" from 1 January 2010, to 31 December 2020, using the ''global'' query category.

RESULTS

The overall interest in PDE5i has doubled. Sildenafil has become the most trend PDE5i of today with a regular increase (AAPC: 0.016, p < 0.01). Although the search trend of tadalafil remained almost constant until 2014, the rate of increase in the last 6 years raised and tadalafil has become the 2nd most popular PDE5i recently (AAPC: 0.007, p < 0.01). For vardenafil there has been a decreased interest (AAPC: -0.009, p < 0.01). There is no significant change in avanafil trend (AAPC: 0.000, p: 0.5). All PDE5i interest on GT decreased notably from February to June 2020. But after June, search trends reached the level before the COVID-19 period in a month.

CONCLUSIONS

These findings show us, with its increasing prevalence, erectile dysfunction (ED) has become a major public health problem. People from different geographies search the internet for ED treatment options. Patients should be informed that ED may be the first sign of many comorbid diseases, and patients with ED should be referred to a health institution for diagnosis and treatment.

A validated LC-MS/MS assay for the quantification of phosphodiesterase-5 inhibitors in human plasma

Phosphodiesterase inhibitors (PDE5i) are considered the first line therapy for erectile dysfunction. All PDE5i available on the market are structurally related; their main differences relate to their pharmacokinetic parameters. For these treatments to be effective and safe, it is necessary that these drugs are in the appropriate doses and that they reach adequate concentrations in the plasma. For this purpose, it is essential to perform therapeutic monitoring using bioanalytical methods. In this way, the present work aimed to develop and validate a new bioanalytical method, based on LC-MS/MS, for the simultaneous quantification of six commercially available PDE5i (avanafil, lodenafil, sildenafil, tadalafil, udenafil, and vardenafil). For this purpose, the human plasma was extracted with diethyl ether and sulfaquinoxaline was established as an internal standard. Separation was achieved using an Xbridge C18 column at 40 °C as the stationary phase, using water and acetonitrile as the mobile phase (both with formic acid and ammonium formate) in gradient mode. The method was validated according to the current guidelines and was found to be selective, linear (from 1 to 200 ng.mL^-1 for all drugs except for tadalafil which is from 5 to 200 ng.mL^-1), precise, accurate, and free of residual and matrix effects. The drugs were considered stable in plasma and in solution under different conditions. The method was applied to volunteerssamples, demonstrating that the method can be used routinely and may be useful in future studies on pharmacokinetics and therapeutic monitoring.

Impact of antiangiogenic treatment on the erectile function in patients with advanced renal cell carcinoma

We longitudinally assessed erectile function as well as the willingness to use pro-erectile treatment in a cohort on AAT for advanced RCC. Thirty-seven patients with advanced RCC completed the five-item version of the International Index of Erectile Function (IIEF-5) and other interview items before (T0) and 12 weeks into therapy (T12) with AAT. Patients were further asked if they were willing to use and pay out-of-pocket for on-demand treatment with phosphodiesterase-5-inhibitors (PDE-5i). Statistical analysis was performed using nonparametric hypothesis testing. The IIEF-5 score at T12 was significantly decreased compared with T0 (p < .001). Subjective patient satisfaction regarding their sexual lives was associated with higher IIEF-5 scores at both time points (p = .006 and p = .03, respectively). At T12, subjective sexual contentment showed a nonsignificant trend towards decline (p = .074). Patients who opted for medical treatment of ED showed significantly better IIEF-5 scores at both time points compared with the rest of the cohort (p < .001 and p = .005, respectively). In summary, AAT seems to have a negative effect on erectile function in RCC patients, however, the role of psychosocial issues warrants further elucidation. Affected patients may benefit from a proactive approach promoting medical treatment of erectile dysfunction during AAT.