The study, “Effect of pirfenidone on cough in patients with idiopathic pulmonary fibrosis,” appeared in the European Respiratory Journal. Its senior author was Dr. Marlies Wijsenbeek of the respiratory medicine department at Erasmus University Medical Center in Rotterdam.
Cough is a common symptom and predictor of IPF progression. But patient response to antitussive therapy is often inadequate. Effective treatments are also lacking due to the absence of extensive studies on cough improvement in IPF. Yet Esbriet may be a promising therapy.
Researchers conducted the study in the Netherlands, Italy, France and Great Britain to evaluate the effect of Esbriet — marketed by Genentech — on coughing in 43 IPF patients (including 33 men and 34 former smokers). They also measured Esbriet’s effect on subjective cough and quality of life.
The patients, aged 40 to 85 years, were recruited between 2013 and 2016. Among the criteria for inclusion: criteria: forced vital capacity (FVC, the amount of exhaled air after a deep breath) ≥ 50% and cough score ≥ 40 mm (0-100. IPF-related cough was observed for no less than eight weeks. Cough recordings were conducted at baseline, and at four and 12 weeks after treatment with Esbriet.
Only 31 patients completed the 12-week study, which found that Esbriet induced a 34 percent decrease in cough. In addition, the drug reduced cough severity. Analysis at four weeks of treatment already showed a significant amelioration, though a smaller, 14 percent, reduction in cough. These results were supported by subjective assessments.
No significant changes were seen in disease-specific quality of life or anxiety, although cough-related quality of life improved with Esbriet treatment.
“This study is the first to show a significant improvement in cough by a pharmacologic treatment, using both objective and subjective measures in IPF patients,” researchers said. “In IPF, increased cough reflex sensitivity is thought to be a key mechanism that causes cough.”
Based on the results, the team concluded “in patients with IPF, pirfenidone treatment significantly reduces objective 24-h cough counts by 34 percent, and improves subjective measures of cough. These results are clinically meaningful to patients. More research is warranted into the mechanisms and management of cough in IPF and other fibrotic diseases.”