New developments in the treatment of hypoactive sexual desire disorder - a focus on Flibanserin

Pharmacotherapy for female sexual dysfunctions (FSDs): what is on the market and where is this field heading?

INTRODUCTION

Female sexual dysfunctions (FSDs) are common in women of any age and have a huge impact on quality of life and relationships. They have a multifaceted etiology limiting the development of pharmacotherapies with a high rate of effectiveness. Safety issues are also a concern.

AREAS COVERED

The authors report the most recent advances in pharmacotherapy for premenopausal and postmenopausal women with a main focus on hypoactive sexual desire disorders (HSDD) and associated sexual symptoms. Good levels of evidence have emerged for psychoactive agents, such as flibanserin and bremelanotide, as well as hormonal compounds (transdermal testosterone). The authors also report briefly on intravaginal DHEA (prasterone), local estrogen therapy (LET), and ospemifene to manage effectively vulvovaginal atrophy/genitourinary syndrome of menopause (VVA/GSM). In addition, they discuss promising therapeutic options highlighting the main reasons that hamper the availability of new labeled products. Finally, they include the importance of the multimodal approach to address FSDs.

EXPERT OPINION

Approved pharmacotherapies for FSD are limited. Validated multidimensional instruments and adequate objective measures of physical and mental responses to sexual external and internal incentives are mandatory to identify women suitable to chronic or on-demand treatments and to assess their pattern of response in research and practice.

Hypoactive sexual desire disorder (HSDD) is not "female erectile dysfunction (ED)": challenges with the characterization of HSDD in women based on a systematic literature review

Objective: Hypoactive sexual desire disorder (HSDD) in women has been viewed inaccurately by some in the medical and payer community as analogous to erectile dysfunction (ED) in men. This literature review aims to highlight the distinctions between HSDD and ED.Methods: Two systematic literature searches were conducted on the epidemiology, symptomatology and biopsychosocial outcomes of HSDD and ED. Studies published since 2007 were considered for HSDD; studies published since 2012 were considered for ED.Results: HSDD in women is primarily a central nervous system condition related to neuroendocrine factors, whereby neural pathways that regulate sexual excitation and/or inhibition appear to be involved. A combination of organic and psychogenic factors often contributes to ED. HSDD and ED are associated with similar psychological and interpersonal consequences, but affect different phases of the sexual response model (desire versus arousal) and have different pathophysiologies, therefore requiring different treatment and outcome paradigms. ED is measured by objective, physiological responses (erection and sexual function), but quantitative assessments for HSDD are more difficult because loss of desire with associated distress has to be assessed. Outcome measures used to assess ED, such as the number of satisfying sexual events, are far less informative as an endpoint for randomized clinical trials of treatments for HSDD.Conclusions: HSDD and ED are distinct conditions affecting different phases of the sexual response model, and thus require clear and unique clinical characterization and adequate communication between the health care professional and patient for appropriate diagnosis, management and treatment.

Female Hypoactive Sexual Desire Disorder: A Practical Guide to Causes, Clinical Diagnosis, and Treatment

Hypoactive sexual desire disorder (HSDD) in women is defined as the persistent or recurrent absence of sexual thoughts or fantasies and/or lack of desire for sexual activity that is associated with marked personal distress and/or interpersonal difficulties, and cannot be better attributed to another primary disorder, medication, or general medical condition. Notably, HSDD shares some similarity with depression, as its etiology can be explained using a biopsychosocial model that includes biological, psychological, and sociocultural factors, as well as interpersonal influences. Due to its high prevalence and negative impact on the overall health and well-being of women, primary care health professionals and women's health practitioners need to be actively aware of HSDD, particularly because patients may be reluctant or unwilling to initiate a discussion about their sexual concerns during routine visits. HSDD is well established as a valid and treatable clinical entity. Even for those inexperienced in treating sexual problems, there are simple and validated screening tools such as the Decreased Sexual Desire Screener that can help identify HSDD and a need for further evaluation and treatment. There have been few established pharmacologic treatments for HSDD. Flibanserin was the first drug approved for the treatment of HSDD by the U.S. Food and Drug Administration (FDA). Bremelanotide, a novel melanocortin receptor agonist, was recently approved by the FDA for the treatment of acquired, generalized HSDD in premenopausal women. Increased awareness and recognition of HSDD as a medical condition should provide an incentive for further clinical development of effective treatments for HSDD.

Topical Alpha-1 Adrenergic Receptor Agonist Applied to the Nipple/Areola Complex Improves Female Orgasmic Function

Background: The impact of nipple sensation and its relationship to sexual function have often been neglected in medical literature. However, several recent studies report the importance of the nipple/areola complex (NAC) in sexual arousal and overall function. The nipple is composed of smooth muscle that can be erected via adrenergic nerves. In two complementary studies, we demonstrate that stimulation of the alpha-1 adrenergic receptor in the NAC with topical adrenergic agents can initiate erection of the nipple, increase NAC sensitivity, and improve sexual function. Materials and Methods: Thirteen breast surgery patients with nipple sensitivity loss were recruited to an unblinded study of topical phenylephrine hydrochloride. Sensitivity to pressure was measured before and after the application of the intervention to the NAC. In a second pilot study, 35 women completed a double-blinded placebo-controlled trial of a novel formulation, RJ101, containing a norepinephrine releasing agent. The intervention or placebo was applied to the NAC 30 minutes before sexual activity over the 4-week trial period. The arousal, lubrication, and orgasm domains of the female sexual function index (FSFI) were used to measure sexual function. Results: The application of phenylephrine hydrochloride was shown to increase nipple sensitivity to pressure by an average of 20% in our cohort of 13 breast augmentation patients. In addition, it was shown that intermittent application of the alpha-1 agonist for 8 weeks increased basal NAC sensitivity. In the follow-up pilot study, we demonstrate that stimulation of the NAC with RJ101 produced statistically significant increases versus placebo in the lubrication and orgasm domains of the FSFI, p = 0.0226 and p = 0.0269, respectively. Conclusion: For the first time, we demonstrate that the application of a topical alpha-1 adrenergic receptor agonist or a norepinephrine-releasing agent increases the sensitivity of the NAC and subsequently significantly improves sexual function.