Clinical trial results of Patara Pharma’s inhaled therapy candidate PA101 for chronic cough caused by idiopathic pulmonary fibrosis (IPF) indicate the medication reduces cough in a disease-specific manner.
The findings, published in the journal The Lancet Respiratory Medicine, were derived from a Phase 2 trial (NCT02412020) of PA101. While IPF patients saw a reduction in cough and improved quality of life using the treatment, participants with chronic idiopathic cough did not experience any benefits.
Patara is now moving toward a Phase 2b study of the therapy, in which researchers will find the optimal dosing of PA101.
“The publication of our Phase 2 results … is an important milestone in our program to treat persistent cough in IPF patients, an often debilitating and difficult-to-treat symptom of IPF,” Bill Gerhart, CEO of Patara Pharma, said in a press release.
Titled “A novel formulation of inhaled sodium cromoglicate (PA101) in idiopathic pulmonary fibrosis and chronic cough: a randomized, double-blind, proof-of-concept, phase 2 trial,” the report described how 24 IPF patients were randomly assigned treatment either with PA101 or a placebo. Twenty-seven patients with idiopathic chronic cough also were included.
Results, which had been presented at an earlier scientific meeting, showed that after 14 days of treatment, IPF patients coughed significantly less — 31.1 percent during the day and 29.1 percent over 24 hours. This translated to a reduction from 55 to 39 coughs per patient during the day after two weeks of treatment.
Researchers considered a reduction of 30 percent clinically significant. Looking only at patients who responded to the treatment according to this cut-off, PA101 reduced daytime cough by 59 percent.
Patients also reported improved cough-related quality of life, but the improvement was not statistically significant. This was likely related to the small size of the study, researchers said.
Importantly, the drug was very well-tolerated, with no significant adverse events reported during the trial.
PA101 is an inhaled version of sodium cromoglicate, a drug that has been used in asthma patients for decades. In an accompanying commentary in the The Lancet Respiratory Medicine, Stuart B. Mazzone, MD, from the University of Melbourne in Australia, supported the notion that the drug likely acts in a more complex manner than previously thought.
It likely has anti-inflammatory actions on several cell types and might impact nerve impulses related to cough, he wrote. Mazzone also applauded the study for taking on an aspect of IPF that has received too little attention.