FDA GRANTS ORPHAN DRUG DESIGNATION
FOR DRUG AIMED AT DUCHENNE MD
PTC124, a compound that may be beneficial for about 15 percent of boys with Duchenne muscular dystrophy (DMD), has received Orphan Drug designation from the U.S. Food and Drug Administration (FDA).
Orphan drug designation is granted by the FDA to promote the development of products that may offer therapeutic benefits for diseases that affect fewer than 200,000 people per year in the United States. The designation provides opportunities for grant funding toward clinical trial costs, tax advantages and other financial incentives to pharmaceutical companies.
PTC124 was developed by PTC Therapeutics of South Plainfield, N.J. The preclinical research was conducted in collaboration with molecular biologist and MDA research grantee H. Lee Sweeney at the University of Pennsylvania.
Dystrophin is a muscle protein that’s needed but missing in boys with DMD. Its absence is caused by a variety of genetic mutations in the dystrophin gene, located on the X chromosome. Some of these mutations, known as “premature stop codons,” can be targeted by PTC124. Such mutations are also called “nonsense” mutations.
The drug allows cells to ignore a genetic mutation that would otherwise instruct the cell’s protein manufacturing mechanisms to prematurely terminate the synthesis of the dystrophin protein.
“PTC 124 represents a very novel way of addressing genetic disease,” said Sharon Hesterlee, director of research development at MDA. “It’s an oral drug that may be able to trigger the production of a needed protein without resorting to more complex strategies like gene therapy.”
Duchenne dystrophy, the most common form of childhood muscular dystrophy, causes progressive deterioration in the strength of voluntary muscles, as well as the muscles controlling breathing and heart function. It generally results in death by age 30. Because of its X chromosome origins, DMD affects males almost exclusively, although female carriers can also have symptoms.
Studies conducted by PTC Therapeutics have confirmed that PTC124 is generally well tolerated in healthy people. Pending FDA approval, PTC expects to advance the compound into phase 2 studies in DMD patients with premature stop codons later this year. The drug may also affect premature stop codon mutations in cystic fibrosis, a genetic respiratory disease, and tests in that condition are also slated for later this year, if the FDA approves them.
“We are very proud of receiving Orphan Drug designation for PTC 124 in the treatment of Duchenne muscular dystrophy due to a nonsense mutation,” said Stuart Peltz, president and CEO of PTC Therapeutics. “We are committed to the development of PTC124 and grateful to have the recognition of the Office of Orphan Products Development.”
MDA is a voluntary health agency working to defeat more than 40 neuromuscular diseases through programs of worldwide research, comprehensive services, and far-reaching professional and public health education.
