Treatment response to sildenafil in men with erectile dysfunction relative to concomitant comorbidities and age

A real-world pilot study assessing treatment satisfaction with avanafil in patients with erectile dysfunction

Background

Avanafil is a second-generation phosphodiesterase type 5 (PDE5) inhibitor, and offers a rapid onset of action (15 minutes). Its real-world data, including treatment satisfaction, are still lacking.

Aim

The study sought to investigate the treatment outcomes of avanafil and the factors impacting treatment satisfaction in a real-world setting.

Methods

Between November 2021 and February 2023, erectile dysfunction (ED) patients prescribed avanafil were consecutively enrolled in this phase 4, open-label, cross-sectional, observational study. At each follow-up visit (4-week intervals), participants completed a questionnaire for assessing the use and treatment-emergent adverse events of avanafil, ED severity, and treatment satisfaction.

Outcomes

The outcome measures included the Sexual Health Inventory for Men (SHIM), and Erectile Dysfunction Inventory of Treatment Satisfaction.

Results

Among 234 patients enrolled, 112 (47.9%) patients had follow-up visits and answered the questionnaire. Treatment with avanafil significantly improved the mean SHIM total score from 10.2 ± 5.6 at baseline to 17.5 ± 6.2 (P < .001). Of the patients treated with avanafil, 71.4% (n = 80 of 112) reported a >4-point improvement in the SHIM total score, and 33.1% (n = 37 of 112) reported normal erectile function. The proportion of patients satisfied with avanafil treatment (defined as Erectile Dysfunction Inventory of Treatment Satisfaction index score ≥60) was 87.5%. Several physical factors (younger age, lower waist circumference, and lower level of low-density lipoprotein), and sexual function factors (shorter duration of ED, higher SHIM total score at baseline, PDE5 inhibitor treatment naive, and acquired premature ejaculation) tended to contribute to satisfaction with avanafil treatment. Treatment-emergent adverse events occurred in 41.1% of patients, and all were mild in severity.

Clinical Implications

This study identifies the factors associated with treatment satisfaction of avanafil, which may ultimately lead to better treatment outcomes.

Strengths and Limitations

This is the first study to provide real-world evidence of avanafil for ED treatment, and validated questionnaires were used to assess erectile function and treatment satisfaction. However, the limitations of this study include single-center observational study design, small sample size, and short-term follow-up.

Conclusion

Avanafil is an effective treatment for ED, and satisfaction rate is high in an outpatient setting. The awareness of identified factors related to patient satisfaction may improve treatment outcomes.

STIM/Orai Inhibition as a Strategy for Alleviating Diabetic Erectile Dysfunction Through Modulation of Rat and Human Penile Tissue Contractility and in vivo Potentiation of Erectile Responses

BACKGROUND

Stromal interaction molecule (STIM)/Orai calcium entry system appears to have a role in erectile dysfunction (ED) pathophysiology but its specific contribution to diabetic ED was not elucidated.

AIM

To evaluate STIM/Orai inhibition on functional alterations associated with diabetic ED in rat and human penile tissues and on in vivo erectile responses in diabetic rats.

METHODS

Rat corpus cavernosum (RCC) strips from nondiabetic (No DM) and streptozotocin-induced diabetic (DM) rats and human penile resistance arteries (HPRA) and corpus cavernosum (HCC) from ED patients undergoing penile prosthesis insertion were functionally evaluated in organ chambers and wire myographs. Erectile function in vivo in rats was assessed by intracavernosal pressure (ICP) responses to cavernous nerve electrical stimulation (CNES). Expression of STIM/Orai elements in HCC was determined by immunofluorescence and immunoblot.

MAIN OUTCOME MEASURES

Functional responses in RCC, HCC and HPRA and STIM/Orai protein expression in HCC. In vivo erectile responses to CNES.

RESULTS

Inhibition of Orai channels with YM-58483 (20 µM) significantly reduced adrenergic contractions in RCC but more effectively in DM. Thromboxane-induced and neurogenic contractions were reduced by STIM/Orai inhibition while defective endothelial, neurogenic and PDE5 inhibitor-induced relaxations were enhanced by YM-58483 (10 µM) in RCC from DM rats. In vivo, YM-58483 caused erections and attenuated diabetes-related impairment of erectile responses. YM-58483 potentiated the effects of PDE5 inhibition. In human tissues, STIM/Orai inhibition depressed adrenergic and thromboxane-induced contractions in ED patients more effectively in those with type 2 diabetes. Diabetes was associated with increased expression of Orai1 and Orai3 in ED patients.

CLINICAL TRANSLATION

Targeting STIM/Orai to alleviate diabetes-related functional alterations of penile vascular tissue could improve erectile function and potentiate therapeutic effects of PDE5 inhibitors in diabetic ED.

STRENGTHS AND LIMITATIONS

Improving effects of STIM/Orai inhibition on diabetes-related functional impairment was evidenced in vitro and in vivo in an animal model and validated in human tissues from ED patients. Functional findings were complemented with expression results. Main limitation was low numbers of human experiments due to limited human tissue availability.

CONCLUSIONS

STIM/Orai inhibition alleviated alterations of functional responses in vitro and improved erectile responses in vivo in diabetic rats, potentiating the effects of PDE5 inhibition. STIM/Orai inhibition was validated as a target to modulate functional alterations of human penile vascular tissue in diabetic ED where Orai1 and Orai3 channels were upregulated. STIM/Orai inhibition could be a potential therapeutic strategy to overcome poor response to conventional ED therapy in diabetic patients. Sevilleja-Ortiz A, El Assar M, García-Gómez B, et al. STIM/Orai Inhibition as a Strategy for Alleviating Diabetic Erectile Dysfunction Through Modulation of Rat and Human Penile Tissue Contractility and in vivo Potentiation of Erectile Responses. J Sex Med 2022;19:1733-1749.

The Efficacy and Safety of Thrice vs Twice per Week Low-Intensity Pulsed Ultrasound Therapy for Erectile Dysfunction: A Randomized Clinical Trial

BACKGROUND

A recent sham-controlled clinical study has shown that low-intensity pulsed ultrasound twice per week can safely and effectively treat patients with mild-to-moderate erectile dysfunction (ED). However, large-scale clinical trials are needed to verify its efficacy and safety and determine a reasonable treatment interval.

AIM

To study whether low-intensity pulsed ultrasound therapy thrice per week is non-inferior to twice per week in patients with mild-to-moderate ED.

METHODS

A randomized, open-label, parallel-group, non-inferiority clinical trial was conducted in 7 hospitals in China. A total of 323 patients with mild-to-moderate ED were randomized (1:1) into thrice per week (3/W) and twice per week (2/W) groups. Low-intensity pulsed ultrasound was applied on each side of the penis for 16 sessions.

OUTCOMES

The primary outcome was response rate using the minimal clinically important difference in the International Index of Erectile Function (IIEF-EF) score at week 12. Secondary outcomes included Erection Hardness Score (EHS), Sexual Encounter Profile, Global Assessment Question, and Self Esteem and Relationship Questionnaire.

RESULTS

Response rates in 3/W and 2/W groups were 62.0% and 62.5%, respectively. Treatment effect in the 3/W group was noninferior to that of the 2/W group, with rate difference lower bound of -0.01% [95% confidence interval -0.11 to 0.10%] within the acceptable margin (-14.0%). No significant difference was found among secondary outcomes. IIEF-EF score showed a significant increase from baseline in the 3/W group (16.8 to 20.7) and 2/W group (17.8 to 21.7), and the percentage of patients with EHS ≥3 increased in the 3/W (54.9% to 84.0%) and 2/W (59.5% to 83.5%) groups. There was no significant difference in response rate between the 2 groups after controlling for strata factors and homogeneous tests. No treatment-related adverse events were reported.

CLINICAL IMPLICATIONS

Low-intensity pulsed ultrasound therapy displays similar efficacy and safety for mild-to-moderate ED when administered thrice or twice per week for 16 sessions. This study provides two options to suit patients' needs.

STRENGTHS & LIMITATIONS

This is a large-sample, randomized, controlled, noninferiority trial study. Short-term follow-up and mostly younger patients are the main limitations.

CONCLUSION

Low-intensity pulsed ultrasound therapy thrice and twice per week showed equivalent therapeutic effects and safety for mild-to-moderate ED in a young and generally healthy population. This therapy warrants further investigation of its potential value in rehabilitation of ED.

Alterations in the phosphodiesterase type 5 pathway and oxidative stress correlate with erectile function in spontaneously hypertensive rats

To explore how alterations in the phosphodiesterase type 5 (PDE5) signalling pathway and oxidative stress correlate with changes in the expression of relaxation and contraction molecules and erectile dysfunction (ED) in the corpus cavernosum smooth muscle (CCSM) of spontaneously hypertensive rats (SHR). In this study, SHR and Wistar‐Kyoto (WKY) rats were used. Erectile function was determined by apomorphine test and electrical stimulation (ES) of cavernous nerve. Masson's trichrome staining and confocal microscopy were performed. Nitric oxide synthase (NOS), PDE5, phosphorylated‐PDE5 and α1‐adrenergic receptor (α1AR) were determined by RT‐PCR and Western blotting while oxidative stress in CC was determined by colorimetric analysis. SHR exhibited obvious ED. CC of SHR showed less SM but more collagen fibres. The expression of NOS isoforms in SHR was significantly decreased while all α1AR isoforms were increased. In addition, PDE5 and phosphorylated‐PDE5 were down‐regulated and its activity attenuated in the hypertensive rats. Meanwhile, the SHR group suffered oxidative stress, which may be modulated by endoplasmic reticulum stress and NADPH oxidase up‐regulation. Dysregulation of NOS and α1AR, histological changes and oxidative stress in CC may be associated with the pathophysiology of hypertension‐induced ED. In addition, PDE5 down‐regulation may lead to the decreased efficacy of PDE5 inhibitors in some hypertensive ED patients and treatment of oxidative stress could be used as a new therapeutic target for this type of ED.