Repligen Reports Positive Phase 2a Clinical Trial Results of RG2417 for Symptoms of Bipolar Disorder

WALTHAM, Mass., Nov. 8 /PRNewswire-FirstCall/ -- Repligen Corporation today announced positive results from a Phase 2a clinical trial of RG2417, an oral formulation of uridine, in patients with bipolar disorder. This was a multi-center study in which 84 patients received either RG2417 or a placebo twice a day for six-weeks. Patients in the RG2417 and placebo groups were well matched in their symptoms at baseline with the exception of mania for which the RG2417 group mania score was significantly higher (p=0.01). The objective of the study was to assess the safety and efficacy of RG2417 on the symptoms of bipolar depression as measured by the co-primary endpoints, the Montgomery-Asberg Depression Rating Scale (MADRS) and the Clinical Global Impression of Change in Bipolar Disorder scale (CGI-BP-C). Patients were evaluated at baseline and then weekly using these standardized tools to assess change in their symptoms. Over the six-week treatment period, the study demonstrated a statistically significant improvement in the symptoms of depression in the patients receiving RG2417 when compared to placebo on the MADRS (p=0.03) and a strong trend toward improvement on the CGI-BP-C (p=0.06).

Secondary observations from the study included a statistically significant decrease in mania score as determined using the Young Mania Rating Scale (YMRS) for mania (p=0.01), in the patients receiving RG2417 over the aggregate six-week treatment period when compared to placebo. Preliminary review of the data suggests that RG2417 was well tolerated. This study was conducted under a development agreement with the Stanley Medical Research Institute, the largest nonprofit provider of funding for research on schizophrenia and bipolar disorder in the United States.

"We are pleased with the results of this study which provides substantial evidence of efficacy of RG2417 in improving the symptoms of bipolar disorder," stated Walter C. Herlihy, President and Chief Executive Officer of Repligen Corporation. "The results of this study support further evaluation of RG2417 in this patient population and will be useful in the design of future clinical studies."

About Bipolar Disorder

Bipolar disorder, also known as manic depression is an illness marked by extreme changes in mood, thought, energy and behavior in which a person's mood can alternate between the "poles" of mania and depression. Bipolar disorder affects more than two million adults in the United States and is usually diagnosed in late adolescence or early adulthood. Bipolar disorder is a chronic illness associated with substantial morbidity and mortality, ranking worldwide behind only unipolar depression and alcohol abuse among psychiatric illnesses for related disabilities and overall economic burden of illness. The lifetime financial burden of bipolar disorder in the United States is about 25,000 per patient, depending on resistance to treatment and persistence of symptoms. Although lithium and anticonvulsants such as valproic acid have substantially improved the prognosis of bipolar disorder, many individuals are unable to tolerate treatment-related side effects, and incomplete clinical response, relapse, and recurrence remain common clinical problems.

About The Stanley Medical Research Institute

The Stanley Medical Research Institute (SMRI) is a nonprofit organization that supports research on the causes and treatment of schizophrenia and bipolar disorder (manic-depressive illness), both through work carried out in its own laboratories and through support of researchers worldwide who are working on these diseases. SMRI is the largest nonprofit provider of research funding for schizophrenia and bipolar disorder in the United States and has provided over 00 million in funding since 1989.

About Repligen Corporation

Repligen Corporation is a biopharmaceutical company focused on the development of novel therapeutics for diseases that affect the central nervous system. In addition, we are the world's leading supplier of recombinant Protein A, the sales of which partially fund the advancement of our development pipeline while supporting our financial stability. Repligen's corporate headquarters are located at 41 Seyon Street, Building #1, Suite 100, Waltham, MA 02453. Additional information may be requested from http://www.repligen.com/.

This press release contains forward-looking statements which are made pursuant to the safe harbor provisions of Section 27A of the Securities Act of 1933, as amended, and Section 21E of the Securities Exchange Act of 1934, as amended. The forward-looking statements in this release do not constitute guarantees of future performance. Investors are cautioned that statements in this press release which are not strictly historical statements, including, without limitation, statements regarding current or future financial performance and position, management's strategy, plans and objectives for future operations, plans and objectives for product development, plans and objectives for present and future clinical trials and results of such trials, plans and objectives for regulatory approval, litigation, intellectual property, product development, manufacturing plans and performance such as the anticipated growth in the monoclonal antibody market and our other target markets and projected growth in product sales, constitute forward-looking statements. Such forward-looking statements are subject to a number of risks and uncertainties that could cause actual results to differ materially from those anticipated, including, without limitation, risks associated with: the success of current and future collaborative relationships, the market acceptance of our products, our ability to compete with larger, better financed pharmaceutical and biotechnology companies, new approaches to the treatment of our targeted diseases, our expectation of incurring continued losses, our uncertainty of product revenues and profits, our ability to generate future revenues, our ability to raise additional capital to continue our drug development programs, the success of our clinical trials, our ability to develop and commercialize products, our ability to obtain required regulatory approvals, our compliance with all Food and Drug Administration regulations, our ability to obtain, maintain and protect intellectual property rights for our products, the risk of litigation regarding our intellectual property rights, our limited sales and manufacturing capabilities, our dependence on third-party manufacturers and value added resellers, our ability to hire and retain skilled personnel, our volatile stock price, and other risks detailed in Repligen's filings with the Securities and Exchange Commission. Repligen assumes no obligation to update any forward-looking information contained in this press release or with respect to the announcements described herein.

Repligen Corporation

CONTACT: Walter C. Herlihy, Ph.D., President and Chief Executive
Officer, 1-781-419-1900, or Laura Whitehouse, Vice President, Market
Development, 1-781-419-1812, both of Repligen Corporation

Web site: http://www.repligen.com/