Avalyn Pharma announced today that it observed statistically significant success in a study of its aerosolized pulmonary fibrosis treatment.

Seattle-based Avalyn presented data from a 24-week Phase 1/2 clinical study at the ISAM conference in Boise, Idaho. The data covered two dose regimens of AP01, a formulation of pirfenidone optimized for delivery through inhalation in patients with idiopathic pulmonary fibrosis (IPF), according to a news release.

The trial randomized 90 patients with IPF to 50 mg doses once daily or 100 mg twice daily, all administered by PARI Pharma’s investigational eFlow nebulizer.

Across 24 weeks, the high dose group registered, on average, no loss of lung function as measured by forced vital capacity (FVC), while the low dose group had a progressive loss of lung function, with the difference proving statistically significant, Avalyn said.

AP01 was safe and well-tolerated in both dosing regimens, while flu-like symptoms and adverse events commonly attributed to oral pirfenidone treatment occurred in less than 10% of patients treated with the therapeutic. The most common adverse events were rash (18% of patients), upper respiratory tract infection (18%) and cough (24%).

Most subjects opted to continue in a 12-month extension of the trial, with the company planning to present long-term efficacy and safety data at an upcoming scientific meeting.

“We are pleased by the efficacy and safety profile we have seen to date with aerosolized pirfenidone in 91 patients over 24 weeks. The six-month FVC data is very promising as well as the overall safety profile to date,” Avalyn Pharma CEO Dr. A. Bruce Montgomery said in the release.

“Despite the 2014 approval of two oral antifibrotic therapies, IPF and other fibrotic lung diseases remain fatal disorders with substantial unmet need. We hope to confirm improved tolerability and long-term efficacy with aerosolized pirfenidone in future Phase 3 trials.”