Cystic Fibrosis Drug Bronchitol Succeeds in Phase 3 Study

FDA submission expected in 2018

An international phase 3 trial of Bronchitol (mannitol, Pharmaxis Ltd.) in adults with cystic fibrosis (CF) has met its primary endpoint. The study was designed to gain marketing approval of Bronchitol in the United States. An FDA submission is expected in 2018.

Bronchitol is a spray‐dried form of mannitol, delivered to the lungs by a portable inhaler. The product is approved for marketing for the treatment of adults (18 years of age and older) with CF throughout the European Union and in Israel, and for patients older than 6 years of age in Australia.

The 26-week, randomized, double-blind, parallel-group study assessed improvements in lung function and other parameters, as well as safety, in 423 adults with CF who had received Bronchitol 400 mg or control twice daily. The study recruited adult patients with all grades of disease who were already receiving standard-of-care therapy.

The trial demonstrated the superiority of Bronchitol versus the comparator on the change from baseline in the forced expiratory volume in one second (FEV1) during the 26-week treatment period (the study’s primary endpoint), with an effect of 54 mL (P = 0.020), corresponding to a 2.2% relative change (P = 0.025). The improvement in lung function was less than that seen in the adult CF population in previous phase 3 studies.

The investigators observed no statistically significant differences between the two treatment groups on secondary endpoints, although a trend was observed in favor of Bronchitol for the change in forced vital capacity (FVC), another lung-function parameter.

Pharmaxis, an Australian company, has partnered with the Chiesi Group from Parma, Italy, for its work on Bronchitol for the U.S. market. Chiesi USA, the American affiliate of the Chiesi Group, is responsible for completing and filing the updated new drug application for Bronchitol with the FDA.

Sources: Pharmaxis; June 13, 2017; and Pharmaxis; July 15, 2016.