In a Phase III, double-blind, placebo-controlled clinical trial, the investigators discovered that a daily dose of pirfenidone could slow the progression of IPF, reducing the loss of lung capacity. The results will be announced at the American Thoracic Society’s 2008 International Conference in Toronto on Tuesday, May 20.
“The most common treatment for IPF is anti-inflammatory agents such as steroids,” said lead researcher Takashi Ogura, M.D., of Kanagawa Cardiovascular and Respiratory Center in Yokohama, Japan. “However our study confirmed that pirfenidone, the main action of which is thought to be antifibrotic, achieved a therapeutic effect on IPF. I expect that our study will serve as a guide to develop a new therapy for IPF in the future.”
The researchers recruited a total of 275 Japanese patients with mild to moderate IPF and randomized them to a high dose pirfenidone (1,800 mg/day) group, a low dose pirfenidone group (1,200 mg/day) and a placebo group. They measured lung capacity (vital capacity or VC) and progression-free survival, defined as a period without death or a greater than 10 percent decrease in VC, to determine the effectiveness of the regimens.
At the end of one year, they found that patients who had been randomized to the high dose regimen had significantly lower loss of VC than the placebo group. Furthermore, pirfenidone slowed the overall deterioration of IPF compared to the placebo.
“Taken altogether, our study demonstrated positive clinical effects of pirfenidone that suppresses the progress of IPF and potentially contributes to improving the outcomes of patients with IPF,” said Dr. Ogura.
Pirfenidone represents new hope, not only for IPF patients who currently have no curative treatment options, but because it is thought to be an antifibrotic agent, it may be able to treat other fibrotic lung diseases, such as interstitial pneumonia with collagen vascular disease and extrapulmonary fibrosis.
“We will continue the follow-up of the patient cohort included in this study to identify whether pirfenidone can contribute to prolonged survival in patients with IPF,” said Dr. Ogura. “Other clinical studies of pirfenidone are also being conducted in the U.S. and Europe, and we hope that our results will be replicated there.”