The neurobiology of bremelanotide for the treatment of hypoactive sexual desire disorder in premenopausal women.

Hypoactive sexual desire disorder (HSDD) is a common female sexual dysfunction and is estimated to affect approximately 10% of women in the United States. It has been suggested that HSDD is associated with an imbalance of hormone and neurotransmitter levels in the brain, resulting in decreased excitation, increased inhibition, or a combination of both. Evidence suggests neurotransmitters, including dopamine (DA), norepinephrine, and serotonin, as well as hormones such as estradiol and testosterone, contribute to female sexual desire and response. Current treatments for HSDD include psychotherapy, and two US Food and Drug Administration-approved medications for premenopausal women: flibanserin, a serotonin mixed agonist and antagonist, and bremelanotide, a melanocortin receptor (MCR) agonist. Melanocortins are endogenous neuropeptides associated with the excitatory pathway of the female sexual response system. MCRs are found throughout the body, including the brain. Bremelanotide is an MCR agonist that nonselectively activates several of the receptor subtypes, of which subtype 4 (MC4R) is the most relevant at therapeutic doses. MC4R is predominantly expressed in the medial preoptic area (mPOA) of the hypothalamus in the brain, and is important for female sexual function. Animal studies suggest that bremelanotide may affect female sexual desire by activating presynaptic MC4Rs on neurons in the mPOA of the hypothalamus, leading to increased release of DA, an excitatory neurotransmitter that increases sexual desire. This review presents what is known about the mechanism of action of bremelanotide in the context of treating HSDD.

Prespecified and Integrated Subgroup Analyses from the RECONNECT Phase 3 Studies of Bremelanotide.

Background: Hypoactive sexual desire disorder (HSDD), the most prevalent female sexual dysfunction, is characterized as persistent diminished desire for sexual activity accompanied by distress. The efficacy and safety of bremelanotide, a melanocortin receptor agonist approved by the U.S. Food and Drug Administration for treatment of acquired generalized HSDD in premenopausal women, were established in the phase 3 RECONNECT studies, two identically designed double-blind randomized placebo-controlled studies with an optional 52-week open-label extension. This report investigates efficacy of bremelanotide versus placebo according to prespecified subgroups (age, weight, body mass index [BMI], and bioavailable testosterone) in the RECONNECT studies. Materials and Methods: Patients self-administered bremelanotide 1.75 mg or placebo subcutaneously using an autoinjector, as needed, before sexual activity for 24 weeks. Efficacy was assessed using change from baseline to end-of-study for Female Sexual Function Index desire domain and Female Sexual Distress Scale-Desire/Arousal/Orgasm Item 13 for bremelanotide versus placebo. Results: Among 1202 patients included in the integrated and subgroup analyses, bremelanotide achieved statistically significant improvements in measures of increased desire and decreased distress associated with low desire across all age, weight, and BMI subgroups, and all baseline bioavailable testosterone quartiles, with few exceptions. Bremelanotide was further associated with statistically significant increases in reported sexual desire (p < 0.05) in patients not taking hormonal contraceptives, and with a numerical advantage in those taking hormonal contraceptives. Patients treated with bremelanotide experienced decreased distress compared with those in the placebo group at levels of statistical significance (p < 0.05) regardless of hormonal contraceptive use. Statistically significant improvements were observed in the presence or absence of decreased arousal, and regardless of HSDD duration. Conclusions: Bremelanotide was associated with statistically significant improvements in sexual desire and reduced distress across several prespecified subgroups, with few exceptions.

Safety Profile of Bremelanotide Across the Clinical Development Program.

Background: Bremelanotide, a melanocortin receptor agonist, is Food and Drug Administration (FDA)-approved for the treatment of premenopausal women with acquired, generalized hypoactive sexual desire disorder. Methods: Review of bremelanotide's safety profile from the clinical development program (phases 1 through 3). Results: The clinical development program comprised 3500 subjects in 43 completed studies. In the phase 3 studies, subjects took bremelanotide for up to 18 months. The most common adverse events (AEs) were nausea (40.0% vs. 1.3%), flushing (20.3% vs. 1.3%), headache (11.3% vs. 1.9%), and injection site reactions (5.4 vs. 0.5), bremelanotide versus placebo groups, respectively, in the integrated double-blind portion of the phase 3 studies (N = 1247). Nausea was the most common reason for bremelanotide discontinuation. There were no deaths; a few subjects experienced serious AEs. Focal hyperpigmentation was rare when bremelanotide was dosed in accordance with label recommendations, but it occurred in more than one-third of subjects following up to 16 consecutive daily dosings. Small and transient but statistically significant blood pressure increases were observed during ambulatory blood pressure monitoring. Most drug-drug interactions were not clinically significant, except for interactions that lowered plasma concentrations of indomethacin and naltrexone. In the double-blind portion of the integrated phase 3 studies, 70% of the bremelanotide group proceeded to the open-label phase of the studies versus 87% of those on placebo. Conclusions: The AEs associated with bremelanotide are mostly mild to moderate. Although not deemed clinically important, bremelanotide should be used with caution in patients at risk of cardiovascular disease, and blood pressure should be well controlled during treatment. Clinical Trial Registration number: NCT02333071 [Study 301] and NCT02338960 [Study 302].

Assessing the Burden of Illness Associated with Acquired Generalized Hypoactive Sexual Desire Disorder.

Background: Hypoactive sexual desire disorder (HSDD), which affects ∼10% of women in the United States, is defined as the persistent or recurrent deficiency/absence of sexual desire accompanied by personal distress. Although HSDD impacts patient quality of life and interpersonal relationships, the disorder often goes unaddressed or untreated. Recent studies of the burden of illness in women with HSDD, especially premenopausal women, are limited. Materials and Methods: A 45-minute web-based survey was designed to investigate the experience of women seeking treatment for HSDD and the impact of this disorder on several psychosocial aspects of women's lives. Women were recruited from an online panel of patients who participated in research studies for compensation. Validated questionnaires assessed sexual function (Female Sexual Function Index) and health-related quality of life (12-Item Short Form Survey [SF-12]), including mental and physical component scores. Results: A total of 530 women, aged ≥18 years, diagnosed with acquired generalized HSDD were included in the study. Premenopausal women indicated greater overall HSDD symptom burden compared with postmenopausal women. Patients with HSDD reported lower SF-12 scores compared with the general population. A multivariable regression analysis demonstrated that psychosocial factors influencing the burden of HSDD, including interference with their relationship with their partner (ß = -0.18; p < 0.005), mental and emotional well-being (ß = -0.23; p < 0.005), and household and personal activities (ß = -0.23; p = 0.02), negatively affected SF-12 mental component scores. Conclusions: HSDD symptom burden was found to be negatively and statistically significantly associated with patients' mental health; the impact was greater among premenopausal women compared with postmenopausal women.

The Patient Experience of Premenopausal Women Treated with Bremelanotide for Hypoactive Sexual Desire Disorder: RECONNECT Exit Study Results.

Background: Hypoactive sexual desire disorder (HSDD) has a significant negative impact on women's overall health and relationships with their partners. Primary analyses from the RECONNECT clinical trials demonstrated statistically significant and clinically meaningful improvements in sexual desire and related distress with bremelanotide relative to placebo in premenopausal women with HSDD. Exit surveys and patient interviews were conducted to evaluate the impact of HSDD and bremelanotide treatment from the patient's perspective. Materials and Methods: Upon completion of the double-blind study but before participation in the open-label extension, up to 250 participants were recruited to complete the quantitative exit survey (17 questions). A subset of up to 90 patients was invited to participate in the telephone interview (17 questions). Patients who volunteered to participate remained blinded to study drug until the survey and interviews were completed. Results: Quantitative exit surveys were completed by 242 RECONNECT participants; 80 of these women also completed qualitative telephone exit interviews. Participants who received bremelanotide described increased feelings of sexual desire, physical arousal, and improvements in overall quality of their sexual activities in their partner relationship. In comparison, women taking placebo reported benefits that did not include the physiological responses described by women receiving bremelanotide, such as positive experiences of seeking HSDD treatment and improved communication with their partner. Conclusions: Exit surveys and patient interviews support the primary findings from RECONNECT and provide quantitative and qualitative assessments of the impact of HSDD on patients' quality of life and the patients' perspectives on the impact of bremelanotide. Clinical trial numbers NCT02333071, NCT02338960.

Comparison of transient elastography, serum markers and clinical signs for the diagnosis of compensated cirrhosis.

BACKGROUND AND AIMS: Non-invasive diagnosis of compensated cirrhosis is important. We therefore compared liver stiffness by transient elastography, APRI score, AST/ALT ratio, hyaluronic acid and clinical signs to determine which modality performed best at identifying compensated cirrhosis. METHODS: Patients undergoing evaluation at a single center were recruited and had clinical, serological, endoscopy, radiological imaging, liver stiffness measurement and liver biopsy. Patients were stratified into cirrhotic and non-cirrhotic. RESULTS: In 404 patients (124 cirrhosis), transient elastography was diagnostically superior to the other modalities yielding an AUC 0.9 +/- 0.04 compared with hyaluronic acid (AUC 0.81 +/- 0.04: P < 0.05), clinical signs (AUC 0.74 +/- 0.04: P < 0.05), APRI score (AUC 0.71 +/- 0.03: P < 0.05) and AST/ALT ratio (AUC 0.66 +/- 0.03: P < 0.05). The optimum cut-off for transient elastography was 12 kPa giving a sensitivity of 89% and specificity of 87% for cirrhosis. In 238 hepatitis C patients (87 cirrhosis), transient elastography yielded an AUC 0.899 +/- 0.02 for cirrhosis and in 166 non-HCV patients (37 cirrhosis) the results were similar with an AUC 0.928 +/- 0.03; with transient elastography being superior to HA, APRI, AST/ALT and clinical signs for all etiologies of cirrhosis (P < 0.05 for all). Importantly, transient elastography was statistically superior at identifying cirrhosis in 38 biopsy proven Childs Pugh A cirrhotics with no clinical, biochemical or radiological features of cirrhosis or portal hypertension (AUC 0.87 +/- 0.04). CONCLUSION: Transient elastography accurately identified compensated cirrhosis; a liver stiffness of >12 kPa represents an important clinical measurement for the diagnosis of cirrhosis.

Reliability and validity of the elements of desire questionnaire in premenopausal women with hypoactive sexual desire disorder.

BACKGROUND: The Elements of Desire Questionnaire (EDQ) is a patient-reported outcome (PRO) measure developed to evaluate sexual desire and was included in two identically designed phase 3 clinical trials (RECONNECT) as an exploratory endpoint. The EDQ was developed based on a literature review, qualitative research with patients with hypoactive sexual desire disorder (HSDD), and input from clinical experts. This instrument is intended to be used to collect efficacy data in clinical trials evaluating potential treatments for HSDD. The objective of this study was to evaluate the measurement properties of both the monthly and daily recall versions of the EDQ during the RECONNECT trials. METHODS: Participants completed the EDQ daily version for 7 consecutive days prior to selected monthly clinic visits. The monthly recall version was completed at each monthly clinic visit. The analysis population consisted of all subjects with Female Sexual Function Index (FSFI) data at baseline and ≥ 1 follow-up visit. RESULTS: At baseline, 1144 and 676 subjects completed the monthly and daily recall EDQs, respectively. The EDQ scores had good internal consistency and test-retest reliability. Monthly and daily recall EDQ scores were correlated with FSFI-desire domain scores at baseline and month 3. Scores from the monthly and daily recall versions were also correlated. After 6 months, there was a significantly greater improvement for bremelanotide versus placebo in both the monthly and daily recall versions (both P < 0.0001). CONCLUSIONS: The results demonstrated that EDQ exhibited good reliability, validity, and sensitivity to change. Consistent with other validated PRO measures of sexual desire, the EDQ provides additional insights into sexual desire. TRIAL REGISTRATION: NCT02338960 and NCT02333071 (RECONNECT studies).

The role of the Bcl-3 proto-oncogene in thyroid hormone-induced liver cell proliferation.

The aim of the study was to determine if thyroid hormone-induced liver cell proliferation occurs through the Bcl-3 proto-oncogene. Rodents (including Bcl-3 knockout mice and the wild-type strain) were injected with a single dose of tri-iodothyronine (T(3)) and sacrificed at various time points. Hepatic mRNA (real-time polymerase chain reaction ) and protein expression (Western analysis) of Bcl-3 was quantified in rats stimulated with T(3). Cell proliferation was induced in a variety of cell types after T(3) injection at 24 h including hepatocytes (7 +/- 1.1% vs. 0.45 +/- 0.025%; P < 0.01), hepatic nonparenchymal cells (3.8 +/- 1.2% vs. 0.3 +/- 0.01%; P < 0.01), renal tubular cells (8.1 +/- 1.6% vs. 0.2 +/- 0.035%; P < 0.01), and splenic lymphocytes (4.8 +/- 1.2% vs. 0.35 +/- 0.02%; P < 0.01). We showed a twofold increase in hepatic Bcl-3 mRNA (P < 0.01) and protein expression (P < 0.01) at 24 h in rats stimulated with T(3). However, there were no differences in the rate of liver cell proliferation between Bcl-3 knockout mice and the wild-type strain (0.4 +/- 0.15% vs. 0.3 +/- 0.1%), indicating that Bcl-3 was not functionally involved in thyroid hormone-induced liver cell proliferation. A single gene is unlikely to initiate the process of thyroid hormone-induced cell proliferation. A complex interaction between the genomic and nongenomic effects of thyroid hormone is likely to regulate the mitogenic effects.