Pilot Study B: In an open label study of 21 OCD patients who responded poorly to at least 12 weeks of SSRI treatment, 12 of these patients, or 57 percent, responded with a 25 percent or greater reduction in Y-BOCS. The average Y-BOCS score in this responder group improved 44 percent from baseline at 12 weeks. Four weeks after discontinuation of low dose ondansetron treatment, the average Y-BOCS score of the responder group worsened 38 percent from the end of treatment score. None of the treated patients experienced symptom exacerbation or significant adverse effects. (Reference: S. Pallanti, S. Bernardi, E. Hollander: Ondansetron augmentation in Treatment-Resistant OCD (TR-OCD): Hot Topics and poster presentation, American College of Neuropsychopharmacology 49th Annual Conference, December 2010.)About OCD Obsessive compulsive disorder (OCD) is characterized by a pattern of unwanted and intrusive thoughts that cause distress and consequent repetitive behaviors aimed at reducing this distress. OCD affects approximately 1 to 2 percent of the U.S. adult population and can significantly impair the lives of patients and their families. Greater social impairment has been reported in patients with OCD as compared to those with social anxiety or panic disorder. It is believed that the overall degree of impairment caused by OCD is comparable to that experienced by patients who suffer with schizophrenia. SSRIs, including Prozac® (fluoxetine), Luvox® (fluvoxamine), Paxil® (paroxetine), and Zoloft® (sertraline), and the tricyclic agent, clomipramine, are the only approved medications for OCD. While these medications are used as first-line treatments for OCD, approximately 40 percent to 60 percent of OCD patients do not respond adequately, and there is no FDA-approved therapy for this group of patients. About Transcept Pharmaceuticals Transcept Pharmaceuticals, Inc. is a specialty pharmaceutical company focused on the development and commercialization of proprietary products that address important therapeutic needs in the field of neuroscience. Intermezzo® (zolpidem tartrate) sublingual tablet C-IV is the first FDA approved Transcept product. Purdue Pharma holds commercialization and development rights for Intermezzo in the United States. Transcept is currently conducting a Phase 2 study of an investigational product, TO-2061, in patients with obsessive-compulsive disorder. For further information about Transcept, please visit www.transcept.com. For information about Intermezzo, please visit www.IntermezzoRx.com. Forward looking statements This press release contains forward-looking statements that involve substantial risks and uncertainties. All statements, other than statements of historical facts, included in this press release regarding our strategy, future operations, future financial position, future revenues, projected expenses, prospects, plans and objectives of management are forward-looking statements. Examples of such statements include, but are not limited to, statements relating to the following: the use of TO-2061 as an adjunctive therapy for patients with OCD who have not adequately responded to first-line treatment with an approved OCD medication; plans to announce top-line results of the TO-2061 Phase 2 study in the first quarter of 2013; and planned treatments and procedures for the TO-2061 Phase 2 study. Transcept may not actually achieve the plans, carry out the intentions or meet the expectations or projections disclosed in our forward-looking statements and you should not place undue reliance on these forward-looking statements. Actual results or events could differ materially from the plans, intentions, expectations and projections disclosed in the forward-looking statements. Various important factors could cause actual results or events to differ materially from the forward-looking statements that Transcept makes, including the following: achieving acceptance of Intermezzo by physicians, patients and third party payors; supplying sufficient quantities of Intermezzo from third party manufacturers and suppliers to meet anticipated market demand; the impact of competitive products and the market for Intermezzo generally; our dependence on our collaboration with Purdue; obtaining, maintaining and protecting regulatory exclusivity and intellectual property protection for Intermezzo; and the ability of Transcept to obtain additional funding, if needed, to support its business activities. These and other risks are described in greater detail in the "Risk Factors" section of Transcept's Quarterly Report on Form 10-Q filed with the SEC on August 13, 2012 and Annual Report on Form 10-K filed with the SEC on March 30, 2012. Forward-looking statements do not reflect the potential impact of any future in-licensing, collaborations, acquisitions, mergers, dispositions, joint ventures, or investments Transcept may enter into or make. Transcept does not assume any obligation to update any forward-looking statements, except as required by law. Contact:Transcept Pharmaceuticals, Inc. Greg MannSr. Director, Corporate Communications(510) 215-3567 firstname.lastname@example.org SOURCE Transcept Pharmaceuticals, Inc.