FDA raises red flag for Pharmaxis' Bronchitol

Pharmaxis has been dealt another blow by the FDA. The Australian company confirmed Tuesday morning that the regulatory agency has rejected its bid to market the cystic fibrosis drug Bronchitol for treatment in U.S. patients.

The FDA reviewed Bronchitol's New Drug Application, and in a letter issued to the company, regulators have recommended that Pharmaxis conduct an additional clinical trial to obtain approval for the drug. The news comes after an FDA advisory panel in January voted that the Australian biotech couldn't prove that Bronchitol was safe and effective.

Bronchitol was previously granted orphan drug designation for the treatment of patients with CF by the FDA. The drug, which helps clear mucus in the lungs of CF patients, is already being used in patients aged 6 years and older in Australia and for patients 18 years and older in the European Union.

"The submitted data do not provide a favorable benefit‐risk balance to support the use of inhaled mannitol in patients with cystic fibrosis 6 years of age and older," the FDA letter says. "The determination of efficacy based on the two clinical trials are not adequate because of the treatment‐related frequent early dropouts in trial 301 for which the primary statistical analyses did not account and the lack of statistical significance in trial 302 for the primary endpoint."

The letter echoes the same concerns the FDA had back in January, when a committee said there were major data gaps in the two Bronchitol clinical trials due to high patient dropout rate--only 66% of patients completed one study while 85% made it through another. 

- here's the press release
- read the Sydney Morning Herald story