S1 Biopharma Doses First Patients in Phase 2a Clinical Trial of Lorexys in Premenopausal Women with HSDD

JERSEY CITY, N.J., July 29, 2013 /PRNewswire/ -- S1 Biopharma, Inc., a developer of first-in-class drugs for sexual dysfunction in women and men, today announced enrollment and dosing of premenopausal women with hypoactive sexual desire disorder (HSDD) in the Phase 2a clinical trial of its leading drug candidate Lorexys (S1P-104).  

"The initiation of this study marks a significant milestone for S1 Biopharma as we advance Lorexys' clinical development," said Nicolas G. Sitchon, chief executive officer of S1 Biopharma. "Despite significant effort over many years, there are no FDA-approved treatments for women with HSDD. We believe Lorexys may provide the first safe and effective treatment option for those whose lives and the lives of their partners are affected by the disorder. By restoring the balance of the key neurotransmitters that regulate sexual desire in the brain we expect that Lorexys will help women with sexual desire and arousal disorders regain a healthy sexual life."

The leading scientific model of the regulation of sexual desire in the brain is the Kinsey dual control model. It explains that sexual inhibition and sexual excitation are kept in balance by activating and inhibiting neurotransmitters including serotonin, norepinephrine and dopamine.

"Lorexys, which is a first-in-class drug for HSDD, was formulated by identifying the two psychiatric medications, bupropion and trazodone, that, when combined in a precise, proprietary ratio, would modulate the activity of these neurotransmitters, neutralize the monoamine modulators' side effects and maximize beneficial effects on sexual function," said Robert E. Pyke, M.D., Ph.D., chief medical officer of S1 Biopharma. "Pilot data supported positive effects, unlike other serotonergic agents or combinations studied in our early drug development. S1P-205, our candidate for the treatment of HSDD in men, is based on the same active components as Lorexys but has been formulated specifically for efficacy in men."

The Phase 2a study's primary objective is to evaluate Lorexys' safety, tolerability and pro-sexual efficacy as compared to bupropion, one of its constituent drugs; other objectives include exploration of the onset and extent of action of Lorexys, as well as the optimal dose.

Dr. Pyke added, "This Phase 2a trial has been designed specifically to capture clinical data on efficacy and safety in a way that will allow us to move Lorexys carefully yet efficiently into late-stage clinical development."

The clinical trial has an adaptive, three-way crossover, open-label design. It is enrolling 30 subjects meeting the DSM-IV-TR criteria for HSDD, and is the first trial to also assess such patients for the newly defined DSM-5 Sexual Interest and Arousal Disorder. Each subject will receive a daily dose of bupropion as an active control for four weeks followed by a week-long washout period, then a daily administration of a low dose of Lorexys for four weeks followed by the washout, and finally a moderate dose of Lorexys followed by another washout. Patients will self-evaluate weekly with questionnaires and be examined at eight clinic visits. Outcome measures for efficacy include validated self-rated scales of Sexual Function and Sexual Distress and global change. Outcome measures for safety include comprehensive evaluations of symptoms and vital signs, plus standard laboratory studies and electrocardiograms. The study will be conducted in up to three clinical sites in the U.S. Data are expected in the first quarter of 2014.

Additional information about the Phase 2a study is available at www.clinicaltrials.gov, identifier NCT01857596.

About HSDD and Sexual Interest and Arousal Disorder

The DSM-IV defines HSDD as a lack or absence of sexual fantasies and desire for sexual activity, as judged by a clinician, which causes marked distress or interpersonal difficulties. ICD-9 and the upcoming ICD-10 also recognize HSDD, though in DSM-5 female sexual arousal and desire disorders are combined into female sexual interest/arousal disorder. Both the DSM-IV and DSM-5 diagnostic categories require that a patient experience significant distress resulting from a loss in desire and arousal. There are currently no FDA-approved drugs for these conditions, although there is a large unmet medical need. In a U.S. study of 30,000 women, it was found that 10% met these criteria for HSDD without depression or other possible causes.

About Lorexys

Lorexys is being investigated as a first-in-class drug for HSDD. It is designed to restore the balance of three neurotransmitters dopamine, serotonin, and norepinephrine that are known to regulate sexual inhibition and sexual excitation. An oral, non-hormonal fixed-dose combination of two antidepressants, bupropion and trazodone, Lorexys is precisely balanced to neutralize the side effects of its individual components. 

About S1 Biopharma

S1 Biopharma is a developer of first-in-class drugs for sexual dysfunction in both women and men. The company's pipeline of therapies is non-hormonal, acting on the sexual centers of the brain by restoring the natural balance of key neurotransmitters. S1 Biopharma's pipeline utilizes its trademark philosophy of identifying and combining mechanistically opposing agents that work synergistically to maximize beneficial effects on sexual function while minimizing side effects. The company's lead compound, Lorexys, is currently in a Phase 2a clinical trial for the treatment of hypoactive sexual desire disorder (HSDD).

For more information please visit www.s1biopharma.com.

SOURCE S1 Biopharma, Inc.