US-based biopharmaceutical firm PTC Therapeutics has started a global confirmatory Phase III clinical trial of Translarna (ataluren), an investigational new drug, in patients with nonsense mutation cystic fibrosis (nmCF).
Nonsense mutations within cystic fibrosis (CF) are categorised as Class I mutations, a severe form of CF resulting in little or no production of the CFTR protein.
The Phase III confirmatory trial is also called as ACT CF (ataluren confirmatory trial in cystic fibrosis).
The trial's primary endpoint is lung function as measured by relative change in percent predicted forced expiratory volume in one second, or FEV1.
PTC Therapeutics chief medical officer Robert Spiegel said: "The ACT CF trial is designed to confirm Translarna's efficacy based on the evidence seen in the previous Phase III study and other earlier work.
"By focusing ACT CF on the patient population that can most readily demonstrate the effect of Translarna, we believe we have optimised our opportunity for a successful trial.
"We look forward to completing ACT CF and ultimately bringing this potential first-in-class treatment to those CF patients who may benefit."
The international, randomised, double-blind, placebo-controlled trial is designed to assess the efficacy and safety of Translarna in patients six years of age or older with nmCF not receiving chronic inhaled aminoglycosides.
A total of 208 patients are expected to be enrolled in the trial, and they are randomly assigned to one of two treatment arms Translarna three times per day (40mg/kg/day) or placebo (morning, midday, evening).
The company said that participants who have completed the Phase III confirmatory trial will have the opportunity to receive Translarna in an extension study, except in countries where the drug is commercially available for the treatment of nonsense mutation cystic fibrosis.