Idiopathic Pulmonary Fibrosis affects about 200,000 people in the United States.  A drug used to treat patients with mild to moderate lung damage from the disease idiopathic pulmonary fibrosis (IPF) is no better than placebo for preserving lung function, according to a study supported by the National Institutes of Health.

The finding is in the final report of a clinical trial called Prednisone, Azathioprine, and N-Acetylcysteine: A Study That Evaluates Response in Idiopathic Pulmonary Fibrosis (PANTHER-IPF). It will be published May 23 in the New England Journal of Medicine.