( PTC124 Targets Nonsense Mutations; Addr...)Targeting Specific Mutations Reveals Promising New Approach to,Treating Genetic Disorders; Preclinical Data Published in Nature,Health

SOUTH PLAINFIELD, N.J., April 23, 2007 /PRNewswire/ -- New preclinical data published online in the current edition of the journal Nature show that PTC124, an investigational new drug designed to bypass nonsense mutations, was efficacious in a preclinical model of Duchenne muscular dystrophy (DMD). It is estimated that approximately 13 percent of the cases of DMD are due to nonsense mutations. PTC Therapeutics, Inc., which discovered and is developing PTC124, has catalogued over 1,800 distinct genetic disorders where nonsense mutations are the cause of the disease in a significant percentage of patients. Nonsense mutations inactivate gene function and are known to cause anywhere from five to 70 percent of the individual cases of most inherited diseases, such as cystic fibrosis (10%) and Hurler's syndrome (70%).

"We are pleased that the Nature paper offers an opportunity for us to describe our novel approach to regulating post-transcriptional control processes," said Stuart W. Peltz, Ph.D., President and Chief Executive Officer of PTC Therapeutics. "As these preclinical data demonstrate, the broad potential of PTC124 lies in its specificity and unique mechanism of action, which has the potential to address the underlying cause of a broad range of genetic disorders due to nonsense mutations."

Dr. Peltz continued, "In addition to the ongoing Phase 2 clinical trials of PTC124 in cystic fibrosis and Duchenne muscular dystrophy, we are evaluating PTC124 in a number of additional genetic disorders."

Post-transcriptional control processes are the cellular regulatory events that take place after an RNA molecule is copied from DNA. These processes are critical to proper cellular function and provide an opportunity for therapeutic intervention through the modulation of protein levels.