AV-101 for Depression
Depression is a global public health concern. The World Health Organization estimates that “depression is the leading cause of disability worldwide, and is a major contributor to the global burden of disease,” affecting 350 million people globally. According to the U.S. Centers for Disease Control and Prevention (“CDC”), about one in ten Americans aged 12 and over takes antidepressant medication.
Current medications in the multi-billion dollar global antidepressant market, including selective serotonin reuptake inhibitors (SSRIs) and serotonin-norepinephrine reuptake inhibitors (SNRIs), have limited effectiveness. Because of their mechanism of action, SSRIs and SNRIs must be taken for several weeks before patients experience any significant therapeutic benefit. Only about 33% of depression sufferers benefit from first round treatment with SSRIs and SNRIs, and the likelihood of achieving remission of depressive symptoms declines with each successive treatment attempt. Although many patients may eventually find an antidepressant drug or drug combination that induces remission of their depressive symptoms after several treatment attempts, systemic effects of the antidepressant medications involved may increase the risks of serious side effects, including suicidal thoughts and behaviors. Suicide is estimated to be the cause of death in up to 15% of individuals with Major Depressive Disorder.
Ketamine, a classic NMDA receptor (NMDAR) channel blocker, has been shown in clinical trials conducted by the U.S. National Institutes of Health (NIH) to act rapidly to alleviate depressive symptoms in treatment-resistant patients suffering with MDD. Although the potential for widespread therapeutic use of ketamine is limited by its high risk for abuse and behavioral impairment, and its requirement for i.v. administration in a clinical setting, discovery of ketamine’s rapid-acting antidepressant effects revolutionized thinking about MDD treatment and stimulated drug development focused on new generation antidepressants, including AV-101, with potential for achieving fast-acting antidepressant effects similar to ketamine without ketamine’s side effects.
The fundamentally novel mechanism of action of VistaGen’s AV-101 places it among a new generation of antidepressants with breakthrough potential to treat millions of MDD sufferers poorly served by SSRIs and SNRIs. Like fast-acting ketamine, AV-101 modulates (down-regulates) NMDA receptor channel activity. However, unlike ketamine’s antagonistic activity, which results from blocking the NMDA receptor channel, AV-101’s antagonistic activity results from selectively binding to and blocking the functionally-required glycine-binding co-agonist site of the NMDA receptor, which may bypass potential adverse effects that occur with ketamine and result in the “glutamate surge” that has been associated with its rapid-acting antidepressant effects.
Following two successful NIH-funded Phase 1 safety studies of AV-101, VistaGen is now collaborating with the NIH on an NIH-funded Phase 2 clinical efficacy and safety study of AV-101 in subjects with MDD, to be completed in late-2015.
Stem Cell Technology-based Drug Rescue
VistaGen's versatile stem cell technology platform, Human Clinical Trials in a Test Tube™, provides clinically relevant predictions of potential heart and liver toxicity of promising new drug candidates long before they are ever tested in animal or human studies.
VistaGen is also using its stem cell technology and customized CardioSafe 3D™ bioassay system for drug rescue, to produce proprietary new chemical entities (NCEs) that are safer variants of drug rescue candidates previously optimized for efficacy by pharmaceutical companies but terminated prior to FDA approval due to heart toxicity. VistaGen’s current CardioSafe 3D drug rescue program is focused on producing and validating a proprietary NCE for cancer.
Jon S. Saxe,
Brian J. Underdown, Ph.D.,
H. Ralph Snodgrass, Ph.D.,
Founder, President and Chief Scientific Officer
Shawn K. Singh, J.D.
Chief Executive Officer
Shawn K. Singh, J.D.
Chief Executive Officer, Director
H. Ralph Snodgrass, Ph.D.
Founder, President and Chief Scientific Officer, Director
Jerrold D. Dotson, CPA
Chief Financial Officer
Gordon Keller, Ph.D.
Chairman, Director, McEwen Centre for Regenerative Medicine, University Health Network
Gerard Sanacora, PhD, MD
Professor of Psychiatry, Yale School of Medicine; Director, Yale Depression Research Program
George Clay, Ph.D.
Chief Operating Officer (retired), Kyowa Pharmaceuticals
Jack Gauldie, Ph.D.
Director, Centre for Gene Therapeutics, McMaster University
James E. Sanders, D.V.M., Ph.D.
Senior Director and Preclinical Development Leader (retired), Johnson & Johnson
Ron Wester, Ph.D. Vice President (retired)
Medicinal Chemistry and Drug Discovery, Pfizer Global R&D