Rexahn Pharmaceuticals, Inc., a leader in development of innovative therapeutics for life-threatening and life-debilitating diseases, announced that it has initiated a phase IIa clinical trial for Serdaxin, for the treatment of major depressive disorder (MDD). The Serdaxin phase IIa study calls for the recruitment of up to 100 patients to evaluate its preliminary efficacy in treating MDD.

Rexahn's phase IIa clinical trial for Serdaxin is designed as a randomized, double blind, dose ranging and placebo-controlled study and will be conducted at multiple sites in the US Serdaxin will be administered as an oral, extended release tablet. Patient enrolment will occur throughout 2009, with preliminary data expected in early 2010.

"We believe that successfully bringing Serdaxin to market will mark a significant development in the treatment of depression and related mood disorders," said Dr Chang Ahn, CEO of Rexahn Pharmaceuticals. "Also, we are excited about Serdaxin's potential as a potent neuroprotective agent as demonstrated in two validated animal models of neurodegenerative diseases where depression is a major co-morbidity and patients still face serious unmet needs."

Serdaxin's mechanism is distinct from standard of care antidepressants (e.g. reuptake inhibitors such as SSRIs) by acting as a dual enhancer of serotonin and dopamine levels in the brain, and achieving onset of effect in less than two days based on animal studies.

Serdaxin is a potential market leading CNS neuroprotective agent and antidepressant. Among lead indications, we are investigating Serdaxin for depression in phase II clinical trials. Serdaxin may achieve greater and broader therapeutic coverage, and appears to have no serious side effects such as nausea, vomiting, insomnia, weight gain, sexual dysfunction, cognitive deficit or motor impairment that are linked to existing antidepressant drugs. Serdaxin has well-established and excellent human safety.

In preclinical studies, Serdaxin had onset of action in less than two days. Based on its novel mechanism as a dual serotonin and dopamine enhancer, it is a potential treatment for multiple CNS disorders where these neurotransmitters are depleted or implicated in CNS-based illnesses, such as Parkinson's disease (PD). Serdaxin has the potential to address both non-motor and motor events of PD by serving as a neuroprotective agent and addressing loss of dopaminergic neurons that lead to loss of control of movements; and further, enhancing serotonin and dopamine levels that are involved in depression and mood disorders. Rexahn has multiple clinical programs planned for investigating Serdaxin in the treatment of anxiety disorders, Parkinson's disease, Alzheimer's and neurodegenerative illnesses, neuroprotection and biodefense uses.