Scientific evidence suggests that depressive symptoms are associated with an overstimulation of NNRs and other receptors in the brain that are activated by the neurotransmitter acetylcholine. This overstimulation is referred to as increased cholinergic tone. TC-5214 is a nicotinic channel blocker that modulates the activity of various NNR subtypes thought to be involved in this increased cholinergic tone.
In December 2009, we announced a collaboration and license agreement with AstraZeneca for the global development and commercialization of TC-5214 for major depressive disorder, or MDD.
Effectiveness of the collaboration and license agreement is contingent on expiration or termination of the waiting period under the Hart-Scott-Rodino Antitrust Improvements Act.
In July 2009, we announced that TC-5214 had achieved all primary and secondary outcome measures in a Phase 2b clinical trial as an adjunct (or add-on) treatment for MDD in subjects who did not respond adequately to first-line treatment with citalopram hydrobromide (a selective serotonin reuptake inhibitor marketed in the United States as Celexa®) alone. We subsequently presented data from the trial at the Nicotinic Acetylcholine Receptors as Therapeutic Targets Symposium, a satellite meeting of the 39th annual meeting of the Society for Neuroscience.
About Major Depressive Disorder
MDD is a serious mental illness characterized by one or more major depressive episodes and believed to affect over 42 million people1 worldwide. The global antidepressant market is estimated at approximately $20 billion.2
According to The National Institute of Mental Health, or NIMH, MDD is the leading cause of disability in the United States for people between the ages 15 and 44. In 2000, the total economic burden of treating depression in the United States was approximately $83.1 billion, with workplace costs, including missed days and lack of productivity due to illness, accounting for approximately 62% of the total economic burden, treatment costs accounting for approximately 31% and suicide-related costs accounting for approximately 7%.3
The Sequenced Treatment Alternatives to Relieve Depression, or STAR*D, study undertaken by NIMH between 2001 and 2006 highlighted the inadequacy of currently available therapies for MDD. Approximately 63% of participants in the study did not achieve remission following initial treatment with the SSRI citalopram alone. The study showed that augmentation therapies may be useful in the treatment of symptoms of depression that do not resolve with first-line treatment.4
1Report: New Developments in Major Depressive Disorder.Decision Resources. August 2009; p. 30.
2Report: The CNS Market Outlook to 2013.Business Insights. 2008; p. 61.
3Greenberg, Kessler, Birnbaum, et al. The economic burden of depression in the Unted States: How did it change between 1990 and 2000? Journal of Clincal Psychiatry. December 2003; 64(12): 1465-1475.
4 Rush, Trivedi, Wisniewski, et al. Acute and Longer-Term Outcomes in Depressed Outpatients Requiring One or Several Treatment Steps: A STAR*D Report. American Journal of Psychiatry. November 2006; 163:1905-1917.