A commonly used three-drug regimen for idiopathic pulmonary fibrosis was found harmful in an NIH clinical trial. In the trial, the triple-drug therapy consisting of prednisone, azathioprine, and N-acetylcysteine (NAC) had poorer outcomes than placebo or inactive substances. NIH stopped the three-drug regimen arm of the trial.
The complete text for the alert is available at: http://www.nlm.nih.gov/databases/alerts/2011_nhlbi_ifp.html