Common Treatment for Patients with Chronic, Progressive Lung Disease Found to be Ineffective
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.
Previous studies suggested that therapies combining N-acetylcysteine, or NAC, with immunosuppressive and anti-inflammatory drugs could slow progression of the disease. IPF affects about 200,000 people in the United States, only half of whom survive more than 2-3 years from initial diagnosis.
“IPF is a devastating disease,” said James Kiley, Ph.D., director of the Division of Lung Diseases at the NIH’s National Heart, Lung, and Blood Institute (NHLBI). “While it is disappointing that NAC was ineffective in preserving lung function in IPF, these are the kind of high-quality data that patients and their caregivers need to make informed decisions.”
Among other measures, researchers relied on forced vital capacity (FVC) to assess changes in lung function. FVC is the total amount of air a person can exhale after taking the deepest breath possible. During 60 weeks of follow-up, the study found no statistically significant difference in FVC declines, IPF symptom flare-ups, deaths, or hospitalizations between patients treated with NAC and those treated with placebo.
“We have made major strides in understanding the biology and clinical implications of pulmonary fibrosis,” said Fernando J. Martinez, M.D., executive vice chair of medicine at Weill Cornell Medical College, New York City, and an author of the study. “As a result, there is tremendous hope for therapeutic options on the horizon.”
IPF, an incurable disease characterized by buildup of fibrous scar tissue within the lungs, causes progressively worsening shortness of breath, coughing, chest pain, and fatigue.
Martinez co-led the research with Ganesh Raghu, M.D., professor of medicine and director of the University of Washington Center for Interstitial Lung Diseases.
Additional authors who wrote the manuscript for the Idiopathic Pulmonary Fibrosis Clinical Research Network (IPFnet) are Joao A. de Andrade, M.D., associate professor of medicine and director of the University of Alabama at Birmingham Interstitial Lung Disease Program; Kevin J. Anstrom, Ph.D., associate professor of bioinformatics and statistics and member in the Duke Clinical Research Institute, Durham, North Carolina; and Talmadge E. King Jr., M.D., professor and chair of the department of medicine at the University of California, San Francisco.
PANTHER-IPF originally was designed as a three-arm clinical trial to compare a multidrug therapy of azathioprine, NAC, and prednisone with placebo and NAC alone.
NIH stopped the multidrug therapy arm of the trial in 2011 because of safety concerns. Interim results from that arm showed that compared with placebo, patients receiving the multidrug therapy had more deaths and more hospitalizations with no difference in lung function.