InterMune today announced that the American Journal of Respiratory and Critical Care Medicine (AJRCCM) published results from a double-blind, randomized, placebo-controlled Phase II trial evaluating pirfenidone for the treatment of patients with idiopathic pulmonary fibrosis (IPF).
This 107- patient study with a planned 12-month treatment period was conducted in Japan by Shionogi & Co., LTD and was terminated after only nine months based on the recommendation of the Data Safety Monitoring Board following an interim analysis. This analysis suggested favorable effects of pirfenidone on acute exacerbations and other efficacy parameters, prompting the decision to stop the trial.
In the 9-months of treatment, acute exacerbations had occurred in 14% and 0% of placebo and pirfenidone patients, respectively (p=0.0031). All of these patients required hospitalization and one patient died. The analysis of the primary endpoint, change from baseline in the lowest oxygen saturation during a 6-minute exercise test, revealed a trend in the overall population (p=0.072) with a more pronounced treatment effect in a pre-specified subgroup of patients with milder disease (p=0.0305). Pirfenidone had a favorable effect on vital capacity, analyzed as both a change from baseline (p=0.0366) and a categorical assessment of the proportion of patients who improved, were stable, or declined (p=0.0028). Changes in total lung capacity, carbon monoxide diffusing capacity, resting partial pressure of arterial oxygen, dyspnea, and quality of life were not statistically significant after nine months of treatment. Gastrointestinal symptoms, photosensitivity and fatigue occurred more frequently in the pirfenidone group, although rates of treatment adherence were similar between the two groups. The main cause for patients discontinuing from study treatment was photosensitivity in the pirfenidone group (6.8% vs. 0%) and acute exacerbation (0% vs. 14%) in the placebo group.