A double-blind, placebo-controlled, efficacy and safety study of topical gel formulation of 1% alprostadil (Topiglan) for the in-office treatment of erectile dysfunction

Scoping review exploring advancements in topical agent therapies for erectile dysfunction

INTRODUCTION

Erectile dysfunction (ED) is a common issue that affects older men and is often associated with various health conditions. Phosphodiesterase 5 inhibitors are commonly used to treat ED; however, their effectiveness may be limited, or the medication may be contraindicated. Therefore, topical gels are being developed as an alternative option for the pharmacologic treatment of ED.

OBJECTIVES

This review aimed to provide an overview of the efficacy and safety of topical agents for the treatment of ED.

METHODS

The PubMed, Cochrane, Embase, and Web of Science databases were searched. Articles were included that investigated ED and topical agents operating through the skin of the penis, evaluated the effectiveness of the treatment, and involved patients randomized into groups.

RESULTS

Topical alprostadil, glyceryl trinitrate (MED2005), and an over-the-counter formulation (MED3000) were used as alternative treatments for ED in 7 articles, which included 3475 patients. Topical alprostadil induced an erection in 67% to 75% of patients. Adequate erections for vaginal penetration were reported in 38.7% of the alprostadil-treated patients vs 6.9% of the placebo-treated patients. Topical alprostadil significantly and dose dependently improved the total score change on the International Index of Erectile Function as compared with the placebo. MED2005 exhibited a rapid onset of action, with nearly 70% effectiveness within 10 minutes. MED3000 met the minimal clinically important difference threshold of a 4-point increase on the erectile function domain of the International Index of Erectile Function, with an improvement of 5.73 points in 24 weeks. Topical therapy for ED also had acceptable safety profiles.

CONCLUSION

Topical agents via various mechanisms are effective and well-tolerated treatments for ED. A fast-acting drug that significantly reduces side effects as compared with other options has been discovered. However, its efficacy relative to current first-line therapies remains unclear. Topical agents present a viable therapeutic alternative for individuals who are unable or unwilling to take oral phosphodiesterase 5 inhibitors.

Prostaglandins as a Topical Therapy for Erectile Dysfunction: A Comprehensive Review

INTRODUCTION

Erectile dysfunction (ED) is a substantial cause of dissatisfaction among many men. This discontentment has led to the emergence of various drug treatment options for this problem.

OBJECTIVES

Unfortunately, due to various interactions, contraindications, and side effects, systemic therapies such as phosphodiesterase-5 inhibitors (including sildenafil, tadalafil, vardenafil, avanafil, etc.) are not welcomed in many patients. These problems have led researchers to look for other ways to reduce these complications.

METHODS

This article holistically reviews the efficacy of topical prostaglandins and their role in treating ED. We sought to provide a comprehensive overview of recent findings on the current topic by using the extensive literature search to identify the latest scientific reports on the topic.

RESULTS

In this regard, topical and transdermal treatments can be suitable alternatives. In diverse studies, prostaglandins, remarkably PGE1 (also known as alprostadil), have been suggested to be an acceptable candidate for topical treatment.

CONCLUSION

Numerous formulations of PGE1 have been used to treat patients so far. Still, in general, with the evolution of classical formulation methods toward modern techniques (such as using nanocarriers and skin permeability enhancers), the probability of treatment success also increases.

Nanotechnology as a tool to advance research and treatment of non-oncologic urogenital diseases

Nanotechnology represents an expanding area of research and innovation in almost every field of science, including Medicine, where nanomaterial-based products have been developed for diagnostic and therapeutic applications. Because of their small, nanoscale size, these materials exhibit unique physical and chemical properties that differ from those of each component when considered in bulk. In Nanomedicine, there is an increasing interest in harnessing these unique properties to engineer nanocarriers for the delivery of therapeutic agents. Nano-based drug delivery platforms have many advantages over conventional drug administration routes as this technology allows for local and transdermal applications of therapeutics that can bypass the first-pass metabolism, improves drug efficacy through encapsulation of hydrophobic drugs, and allows for a sustained and controlled release of encapsulated agents. In Urology, nano-based drug delivery platforms have been extensively investigated and implemented for cancer treatment. However, there is also great potential for use of nanotechnology to treat non-oncologic urogenital diseases. We provide an update on research that is paving the way for clinical translation of nanotechnology in the areas of erectile dysfunction (ED), overactive bladder (OAB), interstitial cystitis/bladder pain syndrome (IC/BPS), and catheter-associated urinary tract infections (CAUTIs). Overall, preclinical and clinical studies have proven the utility of nanomaterials both as vehicles for transdermal and intravesical delivery of therapeutic agents and for urinary catheter formulation with antimicrobial agents to treat non-oncologic urogenital diseases. Although clinical translation will be dependent on overcoming regulatory challenges, it is inevitable before there is universal adoption of this technology to treat non-oncologic urogenital diseases.

Combination therapy with topical alprostadil and phosphodiesterase-5 inhibitors after failure of oral therapy in patients with erectile dysfunction: a prospective, two-arm, open-label, non-randomized study

Phosphodiesterase type 5 inhibitors (PDE5Is) are the first-line therapeutic option for erectile dysfunction (ED), while second-line therapy includes the alprostadil. Due to the different pharmacodynamic mechanism of PDE5Is and alprostadil, a synergistic action is conceivable when they are administered in combination. The aim of present study was to evaluate the efficacy and safety of combination therapy with PDE5I and topical alprostadil in patients with ED non-responders to PDE5I alone. We designed a prospective, two-arm, open-label, non-randomized study. Patients over 18 years old, with a stable sexual relationship for at least 6 months, and ED non-responders to PDE5I monotherapy were included in the study. At baseline the variables assessed were 5-item version of the International Index of Erectile Function (IIEF-5), and Sexual Encounter Profile Questions 2 and 3 (SEP-2 and SEP-3). In addition, all subjects underwent penile dynamic duplex ultrasonography. All patients were assigned to the monotherapy group (Group A) or combination therapy group (Group B) based on their preference. Topical alprostadil 300 μg/100 mg (Virirec®) was the treatment assigned to Group A, while the combination therapy with the last PDE5I taken (at the maximum recommended dose) plus topical alprostadil 300 μg/100 mg (Virirec®) was assigned to Group B. After 3 months from assignment to groups were evaluated IIEF-5, SEP-2 and SEP-3 regarding the last sexual intercourse, and Global Assessment Questionnaire-Questions 1 and 2 (GAQ-1 and GAQ-2). All adverse events (AEs) that occurred during the study period were recorded. A total of 170 patients were included in the study (72 in Group A and 98 in Group B). Fifty-two patients were previously treated with sildenafil 100 mg (30.6%), 6 with vardenafil 20 mg (3.5%), 56 with tadalafil 20 mg (32.9%), and 56 with avanafil 200 mg (32.9%). No significant differences among the study groups were found at baseline (p > 0.05). The mean IIEF-5 score increased significantly in Group B after treatment compared to baseline (12.4 ± 3.4 vs. 17.1 ± 4.5; p < 0.001), conversely patients in Group A showed no significant increase (12.2 ± 2.5 vs. 12.7 ± 3.1; p = 0.148). The number of affirmative responses to SEP-2 was significantly higher after treatment compared to baseline only in Group B (57 vs. 78; p < 0.001). The number of affirmative responses to SEP-3 was significantly higher after treatment compared to baseline in both groups (p < 0.001). The number of affirmative responses to GAQ-Q1 and GAQ-Q2 was significantly higher in Group B compared to Group A (p < 0.001). A total of 59 (34.7%) patients experienced AEs. They were mild, self-limited, and did not cause discontinuation of treatment. No episode of priapism was recorded. No statistically significant difference was recorded between the AEs of the two groups, except for facial flushing that was reported only in Group B (p = 0.021). The combination therapy with topical alprostadil and PDE5I seems to be more effective than topical alprostadil alone without worsening the safety of the treatment.

Topical alprostadil (Vitaros©) in the treatment of erectile dysfunction after non-nerve-sparing robot-assisted radical prostatectomy

OBJECTIVE

The aim of the study is the evaluation of the efficacy and safety of the treatment with topical alprostadil (Vitaros^©) in post-robot assisted radical prostatectomy (RARP) rehabilitation therapy of patients with erectile dysfunction (ED).

METHODS

Seventy-four patients were enrolled and underwent non-nerve-sparing RARP.

INCLUSION CRITERIA

age <75, preoperatively International Index of Erectile Function (IIEF-5) >16, erection hardness score (EHS) ⩾2, weekly sexual intercourse ⩾1, affirmative answers to Sexual Encounter Profile Question (SEP-Q) 2 and SEP-Q3, Charlson Comorbidity Index (CCI) ⩽5, Eastern Cooperative Oncology Group (ECOG) performance status ⩽1, no moderate/severe cardiovascular disease.

RESULTS

Vitaros was administered ⩾2 twice a week. At month 6, the IIEF-5 decreased from 20.5 preoperative to 18.1 post-treatment. EHS score decreased from a mean of 3.3 to a mean of 3.0. The quality of life score decreased from an average of 5.1 to 2.3. Weekly sexual intercourse decreased from an average of 2.1 to 1.7. Six patients dropped out; 89.7% patients showed a positive SEP-Q2 and 77.8% a positive SEP-Q3. All patients responded positively to Global Assessment Questions (GAQ)-1 and 97% to GAQ-2. Of all 68 analyzed patients, 13 (17.6%) switched to intracavernous injection therapy.

CONCLUSIONS

In conclusion, Vitaros may become a viable alternative to common injective therapies in well-selected patients after RARP.

Standards for Clinical Trials in Male and Female Sexual Dysfunction: III. Unique Aspects of Clinical Trials in Male Sexual Dysfunction

This series of articles, Standards for Clinical Trials in Male and Female Sexual Dysfunction, began with the discussion of a common expected standard for clinical trial design in male and female sexual dysfunction, a common rationale for the design of phase I to IV clinical trials, and common considerations for the selection of study population and study duration in male and female sexual dysfunction. The second article in this series discussed fundamental principles in development, validation, and selection of patient- (and partner-) reported outcome assessment. The third and present article in this series discusses selected aspects of sexual dysfunction that are that are unique to male sexual dysfunctions and relevant to the conduct of clinical trials of candidate treatments for men.

Clinical use of alprostadil topical cream in patients with erectile dysfunction: a review

Erectile dysfunction (ED) is a common and debilitating disorder seen in over 50% of men older than 70 years. Oral phosphodiesterase type 5 (PDE5) inhibitors are the mainstay of treatment for ED, but cannot be used by a significant subset of patients due to systemic side effects and drug-drug interactions. Second-line therapy may include intracavernosal therapies, but are associated with poor compliance due to their invasive nature. Alprostadil has a mechanism of action different from that of PDE5 inhibitors. Clinical trials have shown topical alprostadil cream to be effective, increasing the erectile function (EF) score of the International Index of EF by up to 13 points from baseline. It has also proven to be safe and well tolerated, with mild-to-moderate and transient treatment-related adverse events that are generally localized to the application site. Topical alprostadil cream is a safe and effective second-line therapy for ED, indicated for those who cannot tolerate, or are not satisfied with, oral PDE5 inhibitor therapy.

Future prospects in the treatment of erectile dysfunction: focus on avanafil

The treatment of erectile dysfunction (ED) has been revolutionized in the last 15 years with the introduction of type 5 phosphodiesterase (PDE5) inhibitors. Their efficacy, safety, and ease of administration have made them first-line treatment for ED. This article reviews the current therapies available for ED, and the new PDE5 inhibitors that are being investigated. Furthermore, it examines all the current ED treatment options that are in different phases of development (including oral and topical pharmacotherapy, gene therapy, and tissue engineering). A special emphasis is on avanafil, a new PDE5 inhibitor that has been studied extensively in Phase I and II clinical trials and has undergone several Phase III trials. Avanafil is a promising medication for ED due to its favorable pharmacokinetics, safety, and efficacy.

Tracing the development of psychosis and its prevention: what can be learned from animal models

Schizophrenia (SCZ) is a neurodevelopmental disorder manifested symptomatically after puberty whose pharmacotherapy remains unsatisfactory. In recent years, longitudinal structural neuroimaging studies have revealed that neuroanatomical aberrations occur in this disorder and in fact precede symptom onset, raising the exciting possibility that SCZ can be prevented. There is some evidence that treatment with atypical antipsychotic drugs (APDs) prior to the development of the full clinical phenotype reduces the risk of transition to psychosis, but results remain controversial. It remains unknown whether progressive structural brain aberrations can be halted. Given the diagnostic, ethical, clinical and methodological problems of pharmacological and imaging studies in patients, getting such information remains a major challenge. Animal neurodevelopmental models of SCZ are invaluable for investigating such questions because they capture the notion that the effects of early brain damage are progressive. In recent years, data derived from such models have converged on key neuropathological and behavioral deficits documented in SCZ attesting to their strong validity, and making them ideal tools for evaluating progression of pathology following in-utero insults as well as its prevention. We review here our recent studies that use longitudinal in vivo structural imaging to achieve this aim in the prenatal immune stimulation model that is based on the association of prenatal infection and increased risk for SCZ. Pregnant rats were injected on gestational day 15 with the viral mimic polyriboinosinic-polyribocytidylic acid (poly I:C) or saline. Male and female offspring were imaged and tested behaviorally on postnatal days (PNDs) 35, 46, 56, 70 and 90. In other experiments, offspring of poly I:C- and saline-treated dams received the atypical antipsychotic drugs (APDs) clozapine or risperidone in two developmental windows: PND 34-47 and PND 48-61, and underwent behavioral testing and imaging at adulthood. Prenatal poly I:C-induced interference with fetal brain development led to aberrant postnatal brain development as manifested in structural abnormalities in the hippocampus, the striatum, the prefrontal cortex and lateral ventricles (LV), as seen in SCZ. The specific trajectories were region-, age- and sex-specific, with females having delayed onset of pathology compared to males. Brain pathology was accompanied by development of behavioral abnormalities phenotypic of SCZ, attentional deficit and hypersensitivity to amphetamine, with same sex difference. Hippocampal volume loss and LV volume expansion as well as behavioral abnormalities were prevented in the offspring of poly I:C mothers who received clozapine or risperidone during the asymptomatic period of adolescence (PND 34-47). Administration at a later window, PNDs 48-61, exerted sex-, region- and drug- specific effects. Our data show that prenatal insult leads to progressive postnatal brain pathology, which gradually gives rise to "symptoms"; that treatment with atypical APDs can prevent both brain and behavioral pathology; and that the earlier the intervention, the more pathological outcomes can be prevented.

Standards for clinical trials in male sexual dysfunctions

INTRODUCTION

Clinical trials in male sexual dysfunction (MSD) are expanding. Consequently, there is a need for consensus standards in this area.

AIM

To develop an evidence-based, state-of-the-art consensus report on standards for clinical trials in MSD.

METHODS

A literature review was performed examining clinical trials in erectile dysfunction (ED), premature ejaculation (PE), delayed/absent ejaculation, libido disorders/loss of desire, hypogonadism, and Peyronie's disease, focusing on publications published in the last 20 years. This manuscript represents the opinions of eight experts from seven countries developed in a consensus process. This document was presented for peer review and debate in a public forum and revisions were made based on recommendations of chairpersons to the International Consultation on Sexual Medicine.

MAIN OUTCOME MEASURE

Expert opinion was based on the grading of evidence-based medical literature, widespread internal committee discussion, public presentation, and debate.

RESULTS

According to experience and recent publications in dealing with clinical trials in sexual dysfunction, recommendations have been made for conducting trials in patients with ED, PE, delayed ejaculation, libido disorders, hypogonadism, and Peyronie's disease.

CONCLUSIONS

It is important that future clinical trials are conducted using standards upon which investigators can rely when reading manuscripts or conducting new trials in this field.

Potential future options in the pharmacotherapy of female sexual dysfunction

Female sexual dysfunction (FSD) is considered a common medical problem estimated to affect millions of women in the westernized countries. FSD has been classified into four different categories including sexual arousal disorder (FSAD), sexual desire disorder (HSDD), orgasmic disorder and sexual pain disorder. The focus of this article is the potential role of pharmacological compounds currently under development, in the treatment of sexual arousal and orgasmic disorders in order to enhance the sexual response in adult females. While a number of potential therapeutic options are available to date, not one of the pharmacological treatment regimens has been yet considered the Gold standard in the management of symptoms of FSD. This article reviews the rationale and potential benefits of using distinct drug formulations in the treatment of FSD.

Erectile dysfunction

PURPOSE

An overview of the latest concepts advanced with regard to the epidemiology, pathophysiology, and management of male ED is provided.

MATERIALS AND METHODS

Published literature and current paradigms promoted by consensus bodies in the field with regard to the management of ED were reviewed.

RESULTS

ED is a neurovascular phenomenon modulated by hormonal, local biochemical, and biomechanical/structural factors of the penis. Once viewed primarily as a psychological issue, ED is now understood to represent predominantly organic etiologies. It has a significant association with cardiovascular disease and could serve as a harbinger of subsequent cardiovascular events. Goal directed assessment and management implies a focus on patient (and partner) preferences regarding various treatment options. These options range from oral pharmacological agents to surgery and may be pursued according to a stepwise management approach. Psychosocial interventions also may serve as useful therapeutic adjuncts.

CONCLUSIONS

ED is a highly manageable disorder in most patients. The patient and his partner have integral roles in the decision making process, since preferences regarding the importance of sexual activity, and the risks and benefits of treatment will vary greatly among individuals.

EAU Guidelines on erectile dysfunction: an update

The introduction of new oral therapies has completely changed the diagnostic and therapeutic approach to erectile dysfunction. A panel of experts in this field has developed guidelines for the clinical evaluation and treatment based on the review of available scientific information.

An Overview of the Diagnosis and Treatment of Erectile Dysfunction

Epidemiological studies have demonstrated an age-stratified increase in the incidence and prevalence of erectile dysfunction (ED). There is a greater degree of openness today when discussing sexual matters and more information on the treatment of ED is available to the public through the media. Quality-of-life issues are now a matter of great importance to the aging population. Men and their partners are no longer prepared to merely accept ED as a natural consequence of aging. The advent of a simple and effective oral therapy for ED has also indirectly fueled the increase in treatment-seeking behaviour among men. Despite great strides in research into ED, our knowledge and understanding of the pathophysiological mechanisms is still in its infancy. As a result, we are able to treat only the symptom of ED rather than prevent it. Common diseases found in the population, such as diabetes mellitus and coronary artery disease appear to be risk factors for the development of ED. Therefore, physicians need to identify any underlying co-existing organic diseases in their patients presenting with ED. Whenever possible, patients are encouraged to attend their consultation sessions with their partners because ED is a condition affecting 'the couple' and not just the man. Psychogenic aspects of ED should also be explored during the consultation. Efforts need to be made to uncover and address the presence of any psychological stressors, if necessary with the help of a psychosexual therapist. The first-line treatment of ED is oral phosphodiesterase-5 inhibitors. For those who do not respond to oral therapy, there is no defined 'step-ladder' escalation in alternative therapy. It is up to the physician to discuss the options with the patient or couple and reach a decision based on their preference.

Transdermal and topical pharmacotherapy for male sexual dysfunction

Transdermal and topical pharmacotherapies have been used for the treatment of male sexual dysfunctions for some time and are well-accepted treatment modalities for these conditions. A Medline search was conducted for transdermal and topical medications, examining published literature over the past two decades. From this search a comprehensive review has been compiled of the available transdermal and topical treatment options for the treatment of male sexual dysfunctions, particularly erectile dysfunction, Peyronie's disease and hypogonadism. It is likely that the transdermal and topical drug armamentarium for sexual dysfunction, male and female, will grow over the next decade.

Retention and migration of alprostadil cream applied topically to the glans meatus for erectile dysfunction

Retention and migration of a specially designed alprostadil transdermal cream was assessed after single-dose administration to the glans meatus of the penis. Seven men were enrolled in this two-way crossover study. Three subjects self-administered the radio-labeled alprostadil transdermal cream (approximately 100 mg of cream containing 300 microg alprostadil) by inserting the tip of the dispenser into the meatus. In three others, the dose was administered by dispensing the cream dropwise into the metal opening without touching the penis (the preferred and directed method). Retention and migration of the cream mass was measured in the penis with a gamma scintillation camera. The alprostadil transdermal cream was retained in the fossa navicularis at or near 99% in five of six subjects regardless of the method of dosing, thus indicating that the cream formulation performed as designed. A mild, transient burning sensation in the penis was the most common adverse event.

Understanding erectile dysfunction medication preference studies

PURPOSE OF REVIEW

The existence of three phosphodiesterase 5 inhibitors has resulted in an increase in the marketing of the drugs. This has led to a shift in focus from scientifically rigorous endpoints such as efficacy and adverse event profiles to patient preference.

RECENT FINDINGS

Although no consensus currently exists as to the correct methodology for preference studies, some basic guidelines should be adhered to, including: (1) the double-blinding of drug administration; (2) non-biased drug administration instructions; (3) an adequately conducted crossover study; (4) comparison of equivalent doses; (5) standardized preference assessment; (6) declaration of patient demographics; and (7) rigorous statistical analysis. These factors are discussed in the light of the three published preference studies.

SUMMARY

In the final analysis, it is unclear to this author how preference studies impact upon clinician decision-making when confronted by a patient with erectile dysfunction.

Feline penile erection induced by topical glans penis application of combination alprostadil and SEPA (Topiglan)

The objective of this study was to evaluate the efficacy of topically applied prostaglandin E1 (PGE(1))+5% SEPA (soft enhancement of percutaneous absorption) on the glans penis in a feline erection model. Erectile response after glans penis administration of PGE(1)+5% SEPA cream (Topiglan, MacroChem Co., Lexington, MA, USA) was compared to the erectile response after intracavernosal administration of the triple-drug combination (1.65 mg papaverine, 25 microg phentolamine, and 0.5 microg PGE(1)). The placebo cream and increasing concentrations (0.25%, 2.5 mg/ml; 0.5%, 5 mg/ml; and 1%, 10 mg/ml) of PGE(1)+5% SEPA were applied in a total volume of 0.1 ml via a plastic needle-less syringe. The control triple-drug combination was administrated intracavernosally via a 30-gauge needle at the completion of each experiment to serve as a control reference. With each application of placebo, PGE(1)+SEPA, and the triple-drug combination, changes in intracavernosal pressure and systemic blood pressure were continuously monitored. Topical application of PGE(1)+SEPA induced increases in intracavernosal pressure in a dose-dependent manner, with minimal effects on systemic blood pressure. The increases obtained with 1% PGE(1) Topiglan cream were similar to the intracavernosal pressure values elicited by the standard intracavernosal triple-drug combination. These data demonstrate that topical glans penis application of PGE(1)+SEPA can induce an erectile response in cats with minimal systemic adverse effects. Oral pharmacological agents are the first-line treatment for male ED. Studies investigating the effectiveness of noninvasive modalities such as topical therapy should continue, because these agents have the potential to avoid the systemic effects commonly seen with oral therapies. Additionally, topical therapy may also benefit patients who are unresponsive to oral agents or have explicit contraindications. Topical PGE(1) application to the glans penis may become an important treatment option in selected patients suffering from erectile dysfunction.

Deciphering erectile dysfunction drug trials

PURPOSE

Erectile dysfunction affects more than 20 million men in the United States. Currently, there are at least 10 novel erectogenic agents in development. It is incumbent on clinicians and especially urologists to be facile in interpreting data from drug trials investigating such medications.

MATERIALS AND METHODS

A comprehensive review of the literature addressing novel Food and Drug Administration approved erectogenic drugs was conducted using MEDLINE to highlight the key points in the analysis of data arising from these trials.

RESULTS

The major points for analysis include trial design, patient population studied, end points used and adverse event profile. The patients enrolled in erectile dysfunction drug trials should be representative of the general erectile dysfunction population. Assessment of the population includes defining baseline erectile dysfunction severity, co-morbidity profiles and concomitant medication use. Defining clinically meaningful end points is difficult. Several validated questionnaire instruments are available, the most commonly used being the International Index of Erectile Function. Much of the data gathered are based on this self-report inventory. Factors relating to adverse events include frequency of events--per patient and per administration rates--and severity and duration of side effects.

CONCLUSIONS

Several key factors in trial design, patient enrollment and outcome analysis need to be assessed to interpret accurately the data generated from erectile dysfunction drug trials.

Inhibition of the tonic contraction in the treatment of erectile dysfunction

Erectile dysfunction (ED) reduces the quality of life. It is estimated that 52% of men have some degree of ED, which is associated with ageing. While it is clear that there are a variety of current treatment options for ED, each of these has drawbacks and contraindications. A better understanding of the physiological mechanisms involved in penile erection will provide new ways to treat ED. This review not only focuses on the vasoconstrictors and vasodilators that control the state of contraction and relaxation of the corpora cavernosa smooth muscle, but also presents a novel Ca(2+)-sensitising pathway that contributes to maintaining the penis in the non-erect state. Studies have shown that inhibition of the RhoA/Rho-kinase signalling pathway induces penile erection. Further understanding of this RhoA/Rho-kinase pathway may provide a novel alternative treatment for ED.

The efficacy and safety of a topical alprostadil cream, Alprox-TD, for the treatment of erectile dysfunction: two phase 2 studies in mild-to-moderate and severe ED

In two multicenter, placebo controlled, phase 2 studies, patients with mild-to-moderate (n=161, Study 1) or severe (n=142, Study 2) erectile dysfunction (ED) were randomized to receive placebo, 0.05, 0.1, or 0.2 mg (Study 1) or placebo, 0.1, 0.2, or 0.3 mg (Study 2) of topically applied alprostadil (containing a proprietary skin permeation enhancer). The primary efficacy end point in both studies was the change in erectile function (EF) score from baseline to final visit. The changes from baseline for EF scores were -0.8+/-1.1, 1.8+/-1.1, 0.7+/-1.2, and 3.7+/-1.2 (P<0.01; Study 1) and 2.7+/-1.3, 6.29+/-1.4, 6.49+/-1.5, and 9.44+/-1.5 (P<0.001; Study 2) for ascending dose groups in each study. Topical alprostadil was well tolerated with the most common adverse event being urogenital pain. These results suggest this topical alprostadil formulation may be a potentially useful agent for the treatment of ED.

Recent advances in the treatment of erectile dysfunction in patients with diabetes mellitus

OBJECTIVE

To present current information on the pathogenesis of and available therapeutic options for erectile dysfunction (ED) in patients with diabetes.

METHODS

We provide a detailed review of the following topics: (1) peripheral and central neurotransmitter pathways involved in the penile erectile process (for example, nitric oxide, acetylcholine, vasoactive intestinal polypeptide, and prostaglandin E(1)), (2) pathogenesis of ED in patients with diabetes (vascular insufficiency, endothelial dysfunction, and autonomic neuropathy), (3) currently available treatment options for ED and their advantages and disadvantages, (4) potential new avenues for future research, and (5) the possibility of preventive treatment.

RESULTS

Clearly a need exists for effective treatment options for ED in patients with diabetes. Because the development of ED in patients with diabetes is often caused by several interrelated mechanisms, including vascular disease, endothelial dysfunction, autonomic neuropathy, hormone imbalance, and certain medications, a thorough understanding of the various pathways involved in penile erection and their modulation in diabetes is essential for physicians to design an effective treatment plan. Interventions that modulate the erectile pathway at different points include therapies that enhance the erectile mechanism (amplification of the nitric oxide pathway), inhibit the detumescence mechanism, or affect the final common pathway by augmenting smooth muscle relaxation. Oral therapy, intracavernosal injections, transurethral pellets, combination therapy, and surgical procedures are available treatment strategies.

CONCLUSION

Despite the availability of many treatment options for ED, early intervention and prevention (by such measures as improved glycemic control and general reduction of associated risk factors) should be emphasized because many of the diabetes-related complications leading to ED are irreversible.

Topical alprostadil cream for the treatment of erectile dysfunction: a combined analysis of the phase II program

OBJECTIVES

To present a meta-analysis of the efficacy and safety data of two recently completed Phase II studies examining a novel alprostadil topical cream for the treatment of erectile dysfunction (ED).

METHODS

Patients (n = 303) with ED of at least 3 months' duration were randomized to receive placebo or 50, 100, 200, or 300 microg alprostadil in two nearly identical 11-dose, multicenter, at-home studies of a novel topical cream containing alprostadil and a proprietary skin permeation enhancer. The primary efficacy endpoint was the change in erectile function domain score from baseline to the final visit. Secondary endpoints included changes in scores for questions 3 and 4 of the International Index of Erectile Function and standard diary analyses. Safety was assessed by analysis of adverse events, changes in laboratory test results, and physical examination findings.

RESULTS

The mean baseline parameters for the erectile function score, ED history, and secondary diagnoses suggested no significant differences among the treatment groups. The changes from baseline to the final visit erectile function scores were 0.98 +/- 0.84, 3.4 +/- 1.3, 3.4 +/- 0.88 (P <0.05), 5.3 +/- 0.92 (P <0.001), and 9.4 +/- 1.43 (P <0.001) for the ascending dose groups. Most secondary efficacy endpoints were significant for the 200 and 300-microg dose groups. Dose-related trends in efficacy were observed. Adverse events were localized to the application site, were of mild or moderate intensity, and were of short duration.

CONCLUSIONS

These results suggest topical alprostadil cream, when combined with a novel dermal permeation-enhancer, to be a potentially useful agent for the treatment of ED.

Topical agents and erectile dysfunction: is there a place?

Despite the proven efficacy of oral therapy for erectile dysfunction (ED), some patients are unable to take these medications because of drug interactions (ie, sildenafil and nitroglycerin) or a lack of response. Topical agents represent another minimally invasive option for the treatment of ED. This review discusses the impediments to effective topical therapy and examines the developmental status of several candidate drugs. Although still in the investigative stage, topical medications can be another tool in the urologist's armamentarium against ED.

[Erectile dysfunction]

In Spain, based on the IIEF, 19% of males between 25 and 70 years old present some degree of erectile dysfunction (ED). Therefore, around 2,000,000 Spanish men present this condition and could require medical attention for it. Here, we present an up-date of the most important aspects of erectile dysfunction (pathophysiology, diagnosis and treatment). We review, in detail, the oral treatments and future drugs that are presently in the premarketing experimental phase. Diagnostic and therapeutic management of the patient with erectile dysfunction should be individualized, taking into account the goals of each patient. It is highly recommendable to carry out a basic assessment (comprehensive clinical history, physical examination, recommended lab testing). If previously undiagnosed diseases are discovered (diabetes, arteriosclerosis, etc.) these should be treated and modifiable risk factors should be corrected. There are numerous therapeutic options for the treatment of erectile dysfunction. Replacement therapy with testosterone should only be used in males with ED and low levels of this hormone, under medical supervision. At present, first line treatment consists of the administration of oral drugs (sildenafil, apomorphine). There are two new PDE 5 inhibitors (tadalafil and vardenafil) that will be released on the market 2003, which will provide better selectivity. Moreover, several drugs for oral administration are in the initial phases of research that will facilitate erection via a direct penile action. When oral drugs are contraindicated, are not effective or when they are unpopular with the patient, the second line of treatment is intracavernous injection. Prostaglandin E1 is the initial drug of choice in patients using intracavernous autoinjection for the first time and has a high efficacy. Implantation of a penis prosthesis and penile revascularisation are appropriate for highly selected patients. Psychotherapy can be an option for men with ED of psychogenic origin, either as a monotherapy or combined with sildenafil or apomorphine.

Pharmacological aspects of erectile dysfunction

Erectile dysfunction (ED) is a common problem with a prevalence of approximately 50% in men aged 40 to 70. There are several etiologies for ED including vasculogenic, neurogenic, hormonal and/or psychogenic factors; one-fourth of ED cases can be drug-related. Penile erection involves a complex interaction between the CNS and local factors. It is a neurovascular event modulated by psychological and hormonal factors. Pharmacologically, neural modulation and endocrine status are very important to attaining penile erection. There have been several significant advances for the pharmacologic treatment of ED. Treatments include agents that are not only orally effective, but possess either local or central acting mechanisms of action. Apomorphine, a centrally-acting agent, is effective in the treatment of ED. Sildenafil, another orally effective agent, acts by inhibiting cyclic GMP-specific phosphodiesterase Type V. Testosterone can be effective transdermally. Non-orally active agents include alprostadil and papaverine. Phentolamine and trazodone are effective in selected cases. Some agents can interact with other medications. Several pharmacological agents, some with central-acting mechanisms and some with Iocally-acting vascular effects, are therapeutically useful in the treatment of ED.