Genzyme, PTC Therapeutics Cystic Fibrosis Drug Relieves Symptom
Posted May 24 2009 10:50pm
An experimental cystic fibrosis drug made by PTC Therapeutics Inc. and Genzyme Corp. increased lung function and helped patients maintain their weight in a study.
The treatment helped relieve symptoms in patients whose disease is tied to certain genetic mutations, according to company-sponsored research published in the U.K.-based medical journal, The Lancet. The DNA variant causes cystic fibrosis in 10 percent of 70,000 patients worldwide and most patients in Israel, according to the researchers from Hadassah Hebrew University Hospital in Jerusalem.
The drug, known as PTC124, bypassed the defect, allowing functional proteins to form and produce thin, freely flowing mucus, the researchers said. In the disease, a sticky form of mucus builds up in the lungs, making breathing difficult and leading to infection and inflammation. The pill helped 16 of 23 patients tested in the study.
``Further development of PTC124 could offer a practical means to address the underlying cause of disease in patients with nonsense mutations as the basis for cystic fibrosis,'' researcher Eitan Kerem said, referring to the genetic variants. ``Because nonsense mutations are causative in some patients with most inherited conditions, such an approach could also be applied to other genetic disorders.''
Cambridge, Massachusetts-based Genzyme, the world's largest maker of drugs for rare genetic disorders, agreed to pay PTC of South Plainfield, New Jersey, at least $100 million in a collaboration to develop the medicine for cystic fibrosis and Duchenne muscular dystrophy.
The PTC-sponsored study was the second of three sets of clinical trials required for regulatory approval. Use of PTC124 was also associated with a reduction in the cells of the immune system that respond to inflammation, the researchers said.
``Given the overall positive findings, future placebo- controlled efficacy trials seem warranted,'' Stephen Hyde and Debora Gill from the UK Cystic Fibrosis Gene Therapy Consortium & John Radcliffe Hospital in Oxford wrote in a comment. ``Additional studies are needed to establish PTC124's molecular target and extend these positive results to other diseases.''
Lori Gorski, a Genzyme spokesperson, declined to comment.
PTC, a closely held company, also is conducting clinical trials on PTC124 to treat Duchenne muscular dystrophy, a rapidly worsening form of the inherited disease effecting about 10,000 patients in the U.S., according to the National Institutes of Health Web site. Genzyme and PTC are enrolling patients in a second phase trial for muscular dystrophy that is expected to include 165 patients, the companies said in a July 17 press release.