Alan Riley

Bio: Alan Riley is an academic researcher. The author has contributed to research in topics: Sexual function & Erectile dysfunction. The author has an hindex of 2, co-authored 2 publications receiving 4566 citations.

Clinical update on sildenafil citrate

Abstract: The timing of this edition's supplement containing papers on the pharmacokinetic and pharmacodynamic properties of sildenafil citrate (Viagra®, Pfizer) appears very apt. It comes at a time when sildenafil has been marketed in Europe for approximately 3 years and when there is increasing interest and focus on men's health. Indeed a recent edition of the British Medical Journal focused on the Men's Health Movement and related issues [1]. Several issues warrant updating and discussion. What has happened to sildenafil since it received regulatory approval in 1998? How has sildenafil been received in the market place? What further studies have been performed, and what more do we know about sildenafil than we did 3 years ago? Have the initial encouraging results of sildenafil effectiveness in clinical trials withstood the test of independent scrutiny? How have governments reacted to the arrival of what some consider to be a ‘lifestyle drug’? How safe is sildenafil? What future directions are PDE5 inhibitor research projects likely to take? What has the advent of sildenafil done for sexual medicine?

The Female Sexual Function Index (FSFI): A Multidimensional Self-Report Instrument for the Assessment of Female Sexual Function

Abstract: This article presents the development of a brief, self-report measure of female sexual function. Initial face validity testing of questionnaire items, identified by an expert panel, was followed by a study aimed at further refining the questionnaire. It was administered to 131 normal controls and 128 age-matched subjects with female sexual arousal disorder (FSAD) at five research centers. Based on clinical interpretations of a principal components analysis, a 6- domain structure was identified, which included desire, subjective arousal, lubrication, orgasm, satisfaction, and pain. Overall test-retest reliability coefficients were high for each of the individual domains (r=0.79 to 0.86) and a high degree of internal consistency was observed (Cronbach’s alpha values of 0.82 and higher) Good construct validity was demonstrated by highly significant mean difference scores between the FSAD and control groups for each of the domains (p<0.001). Additionally, divergent validity with a scale of marital satisfactio...

Development and evaluation of an abridged, 5-item version of the International Index of Erectile Function (IIEF-5) as a diagnostic tool for erectile dysfunction.

Abstract: An abridged five-item version of the 15-item International Index of Erectile Function (IIEF) was developed (IIEF-5) to diagnose the presence and severity of erectile dysfunction (ED). The five items selected were based on ability to identify the presence or absence of ED and on adherence to the National Institute of Health’s definition of ED. These items focused on erectile function and intercourse satisfaction. For 1152 men (1036 with ED, 116 controls) analyzed, a receiver operating characteristic curve indicated that the IIEF-5 is an excellent diagnostic test. Based on equal misclassification rates of ED and no ED, a cutoff score of 21 (range of scores, 5‐25) discriminated best (sensitivitya 0.98, specificitya 0.88). ED was classified into five severity levels, ranging from none (22‐25) through severe (5‐7). Substantial agreement existed between the predicted and ‘true’ ED classes (weighted kappaa 0.82). These data suggest that the IIEF-5 possesses favorable properties for detecting the presence and severity of ED.

Drug repositioning: identifying and developing new uses for existing drugs

Abstract: Biopharmaceutical companies attempting to increase productivity through novel discovery technologies have fallen short of achieving the desired results. Repositioning existing drugs for new indications could deliver the productivity increases that the industry needs while shifting the locus of production to biotechnology companies. More and more companies are scanning the existing pharmacopoeia for repositioning candidates, and the number of repositioning success stories is increasing.

Oral sildenafil in the treatment of erectile dysfunction. Sildenafil Study Group.

Abstract: BACKGROUND Sildenafil is a potent inhibitor of cyclic guanosine monophosphate hydrolysis [corrected] in the corpus cavernosum and therefore increases the penile response to sexual stimulation. We evaluated the efficacy and safety of sildenafil, administered as needed in two sequential double-blind studies of men with erectile dysfunction of organic, psychogenic, and mixed causes. METHODS In a 24-week dose-response study, 532 men were treated with oral sildenafil (25, 50, or 100 mg) or placebo. In a 12-week, flexible dose-escalation study, 329 different men were treated with sildenafil or placebo, with dose escalation to 100 mg based on efficacy and tolerance. After this dose-escalation study, 225 of the 329 men entered a 32-week, open-label extension study. We assessed efficacy according to the International Index of Erectile Function, a patient log, and a global-efficacy question. RESULTS In the dose-response study, increasing doses of sildenafil were associated with improved erectile function (P values for increases in scores for questions about achieving and maintaining erections were <0.001). For the men receiving 100 mg of sildenafil, the mean score for the question about achieving erections was 100 percent higher after treatment than at base line (4.0 vs. 2.0 of a possible score of 5). In the last four weeks of treatment in the dose-escalation study, 69 percent of all attempts at sexual intercourse were successful for the men receiving sildenafil, as compared with 22 percent for those receiving placebo (P<0.001). The mean numbers of successful attempts per month were 5.9 for the men receiving sildenafil and 1.5 for those receiving placebo (P<0.001). Headache, flushing, and dyspepsia were the most common adverse effects in the dose-escalation study, occurring in 6 percent to 18 percent of the men. Ninety-two percent of the men completed the 32-week extension study. CONCLUSIONS Oral sildenafil is an effective, well-tolerated treatment for men with erectile dysfunction.