Pirfenidone: Clinical trials and clinical practice in patients with idiopathic pulmonary fibrosis.

Pirfenidone is an oral drug that exerts not only anti-fibrotic activity but also pleiotropic effects, such as anti-inflammatory and anti-oxidative effects. Because it suppresses reduction in vital capacity and improves progression-free survival, it was approved in October 2008 in Japan for the first time in the world as an anti-fibrotic agent for treatment of idiopathic pulmonary fibrosis (IPF). In October 2014, the agent was approved in the U.S., based on the results of the ASCEND study. Today, it is commercially available in 38 countries worldwide. In clinical practice, it is important to pay attention to the balance between the effectiveness and adverse events (such as gastrointestinal symptoms and photosensitivity reactions, among others) of treatment with pirfenidone. It is important to investigate pirfenidone׳s most cost-effective usage, and the ideal time of treatment initiation, the condition in which treatment should be initiated, and duration of treatment.