Dynogen Awarded U.S. Patent for Use of DDP225 in Overactive Bladder.

-Company Continues to Expand its DDP225 Patent Portfolio in Multiple Clinical Areas-

WALTHAM, Mass. -- Dynogen Pharmaceuticals, Inc. announced today that it has been awarded United States Patent No. 7,115,606, which claims the use of DDP225 for the treatment of overactive bladder (OAB) in patients who are not incontinent. This newly issued patent represents Dynogen's third U.S. patent for DDP225 and its second U.S. patent for DDP225 in the genitourinary disorders field. U.S. Patent No. 6,846,823, which was awarded to Dynogen in January of 2005, covers the use of DDP225 for the treatment of specific lower urinary tract disorder symptoms, such as urinary frequency, urinary urgency and nocturia (the disturbance of nighttime sleep because of the need to urinate).

"Dynogen has quickly built and advanced a very robust portfolio of worldwide patent rights related to DDP225 in multiple disease areas. The United States Patent Office has again acknowledged Dynogen's important contributions to the understanding of DDP225 and its potential use in a number of therapeutic indications," said Mark Boshar, Vice President of Legal Affairs and Chief Patent Counsel at Dynogen.

DDP225 is currently in a Phase 2 clinical trial for irritable bowel syndrome with diarrhea (IBS-d). Lee R. Brettman, M.D., Chief Executive Officer of Dynogen, commented, "We look forward to seeing the results of our Phase 2 proof of concept study for DDP225 in IBS-d next year. While our near-term clinical focus for this candidate remains IBS-d, DDP225 is backed with promising preclinical data in additional indications, such as OAB, which may eventually allow us to expand our clinical pipeline."

About Overactive Bladder

Overactive bladder (OAB) is a chronic condition characterized by urinary urgency, urinary frequency and nocturia with or without urge incontinence. OAB affects about 32 million people in the United States. The vast majority of individuals with OAB (approximately 85% of males and 50% of females) do not experience incontinence.

About DDP225

DDP225 is both a noradrenaline reuptake inhibitor (NARI) and a serotonin type 3 (5-HT3) receptor antagonist. Noradrenaline and serotonin are neurotransmitters that are known to be involved in the control of the gastrointestinal (GI) and genitourinary (GU) systems. The unique combination of noradrenaline reuptake inhibition and serotonin antagonism in one orally delivered compound represents a novel approach to treating IBS-d and other GI and GU diseases. Dynogen licensed preclinical and clinical data related to DDP225 from Mitsubishi Pharma in October 2003.

About Dynogen Pharmaceuticals, Inc.

Dynogen is a clinical-stage company developing a portfolio of more effective treatments for gastrointestinal and genitourinary disorders. The Company is focused on capturing value in attractive and untapped markets in disease areas that severely impair a patient's quality of life, such as irritable bowel syndrome, gastroesophageal reflux disease and overactive bladder. The Company leverages its development expertise to identify promising clinical compounds and rapidly advance them towards registration. Dynogen currently has multiple double-blind, placebo-controlled Phase 2 studies underway. www.dynogen.com.