Zoraxel is a developmental stage drug for sexual dysfunction that directly modulates the sexual activity control center in the brain. Zoraxel enhances the action of serotonin and dopamine, brain signaling molecules that play a key role in three phases of male sexual activity: arousal, erection and release. Zoraxel is the first ED therapeutic to affect all three of these phases.
Preclinical studies demonstrated that Zoraxel improves sexual performance via enhanced motivation and arousal. Its centrally acting mechanism also warrants potential use in the treatment of female sexual dysfunction.
Erectile dysfunction (ED) causes the consistent inability to attain and maintain an erection sufficient for satisfactory sexual intercourse. Erectile problems may be due to ‘psychogenic’ causes (e.g., depression or stress), ‘organic’ causes, or both. The launch of the first orally available phosphodiesterase (PDE)-5 inhibitor, Viagra®, in 1998 established a new standard care for ED and pioneered a new market. Cialis® and Levitra® were subsequently launched in 2003 as second-generation PDE-5 inhibitor drugs. However, 30% of patients are refractory to the leading PDE-5 inhibitor drugs. In addition, PDE-5 inhibitors also increase the risk of a variety of cardiovascular diseases, including heart attack. Zoraxel also has superior safety compared to PDE-5 inhibitors. Contrary to peripherally acting PDE-5 inhibitors, Zoraxel is centrally acting in the brain affecting all three functions of sexual activity.
The Phase IIa clinical trial of Zoraxel is now complete with positive results. The double blind, randomized, placebo-controlled, dose ranging study found that human subjects treated with Zoraxel demonstrated improved erectile function as measured by changes over the International Index of Erectile Function (IIEF) baseline score within the 8-week treatment period. The study, which was designed to assess Zoraxel’s safety and preliminary efficacy in male subjects ages 18 to 65 with ED, demonstrated a dose dependent treatment effect achieved by Zoraxel as assessed by the IIEF survey. Zoraxel was found to be safe and well tolerated, with no serious adverse events reported. Furthermore, subjects treated with Zoraxel demonstrated improved erectile function and significant improvement in the quality of life measures. The Phase IIb trial, which will include the Sexual Encounter Profile (SEP) survey, IIEF and quality of life study endpoints will continue through 2010-11.