Industry Partner News: PTC Therapeutics Announces Positive Data from its Translarna™ Phase II Clinical Trial in Children as Young as Two Years with Nonsense Mutation Duchenne Muscular Dystrophy

SOUTH PLAINFIELD, N.J., July 9, 2018 /PRNewswire/ -- PTC Therapeutics, Inc. (NASDAQ:PTCT) today announced the presentation of data from the Translarna (ataluren) Phase II Study 030 demonstrating that the safety and pharmacokinetic profile of Translarna in children from two to five years with nonsense mutation Duchenne muscular dystrophy (nmDMD) was consistent with that for older children.1  Importantly, the data also showed that treatment with Translarna resulted in improvements in timed function tests and the North Star Ambulatory Assessment from baseline at weeks 28 and 52, with mean changes showing as much as a 25 percent improvement after one year.1 The data at 28 weeks formed the basis of the recent positive opinion from the Committee for Medicinal Products for Human Use (CHMP) of the European Medicines Agency (EMA) to expand the current indication of Translarna to include nmDMD ambulatory children from two to five years of age.2  The data was presented at the International Congress on Neuromuscular Diseases in Vienna.

Translarna is the only approved treatment to address the underlying cause of nmDMD, a rare, genetic, muscle-wasting disease,1 and is currently licensed in Europe for ambulatory patients aged five years and older.3

"We are excited to demonstrate that Translarna showed an improvement over one year of treatment in patients with nonsense mutation Duchenne as young as two years of age," stated Stuart W. Peltz, Ph.D., Chief Executive Officer of PTC Therapeutics, Inc. "Irreversible muscle damage starts before the age of five. Early intervention is critical to maintain muscle function and delay disease progression."

An interim analysis of Study 030 demonstrated that at week 28, the safety and pharmacokinetic profile for Translarna in children aged two to five years is consistent with that for older children.1 Clinical benefits were also observed at 28 weeks with Translarna, with decreases versus baseline in the time to run/walk 10 meters, climb four stairs, and stand from lying face up (supine).1 The most common adverse events included pyrexia, ear infection, and nasopharyngitis.1

Study 030 evaluated changes in timed function tests (TFTs) and the 3-part, 8-part and full (16) items North Star Ambulatory Assessment (NSAA) scales, adopted for children under five years of age (N=12).1 Results summarized in the table below.

About Study 0301

Study 030 was an open-label, Phase 2 study designed to evaluate the safety and pharmacokinetics (PK) of ataluren (10, 10, and 20 mg/kg) in patients aged ≥2 to <5 years with nmDMD. The study includes a 4-week treatment period, a 48-week extension period, and a 4-week follow-up period. Secondary objectives in Study 030 evaluated changes in timed function tests (TFTs) and the total, 3-part,8-part and full (16) items North Star Ambulatory Assessment (NSAA) scales, adapted for children <5 years of age. All patients were male (N=14) with genotypic confirmation of nmDMD. Two patients were excluded from the current analysis: one patient did not have reported functional assessment at Week 28; and one patient did not have baseline measurement all for post-line evaluations, resulting in N=12. Seven out of the fourteen patients in the safety population (50%) reported ≥1 treatment-emergent adverse event (TEAE) during the extension phase, all of which were deemed unrelated to the study drug; there were no serious TEAEs or discontinuations due to a TEAE. Pyrexia, ear infection, and nasopharyngitis were the most common TEAEs, each occurring in 2 patients (14.3%).

About ataluren (Translarna™)

Ataluren, discovered and developed by PTC Therapeutics, Inc., is a protein restoration therapy designed to enable the formation of a functioning protein in patients with genetic disorders caused by a nonsense mutation. A nonsense mutation is an alteration in the genetic code that prematurely halts the synthesis of an essential protein. The resulting disorder is determined by which protein cannot be expressed in its entirety and is no longer functional, such as dystrophin in Duchenne muscular dystrophy. Translarna, tradename of ataluren, is licensed in the European Economic Area for the treatment of nonsense mutation Duchenne muscular dystrophy in ambulatory patients aged five years and older. Ataluren is an investigational new drug in the United States. The development of ataluren has been supported by grants from the Muscular Dystrophy Association; FDA's Office of Orphan Products Development; National Center for Research Resources; National Heart, Lung, and Blood Institute; and Parent Project Muscular Dystrophy.

About Duchenne Muscular Dystrophy

Primarily affecting males, Duchenne muscular dystrophy (DMD) is a rare and fatal genetic disorder that results in progressive muscle weakness from early childhood and leads to premature death in the mid-twenties due to heart and respiratory failure. It is a progressive muscle disorder caused by the lack of functional dystrophin protein. Dystrophin is critical to the structural stability of all muscles, including skeletal, diaphragm, and heart muscles. Patients with Duchenne can lose the ability to walk as early as age ten, followed by loss of the use of their arms. Duchenne patients subsequently experience life-threatening lung complications, requiring the need for ventilation support, and heart complications in their late teens and twenties. More information on the signs and symptoms of Duchenne can be found at: www.duchenneandyou.com

About PTC Therapeutics, Inc.

PTC is a science-led, global biopharmaceutical company focused on the discovery, development and commercialization of clinically differentiated medicines that provide benefits to patients with rare disorders. Founded 20 years ago, PTC Therapeutics has successfully launched two rare disorder products and has a global commercial footprint. This success is the foundation that drives investment in a robust pipeline of transformative medicines and our mission to provide access to best-in-class treatments for patients who have an unmet medical need.