According to a PharmaLive report, one arm of a study evaluating treatments for idiopathic pulmonary fibrosis (IPF) has been stopped due to safety concerns.

The PANTHER-IPF (Prednisone, Azathioprine, and N-acetylcysteine: A Study that Evaluates Response in Idiopathic Pulmonary Fibrosis) study was designed to evaluate whether the combination of prednisone, azathioprine, and N-acetylcysteine (NAC) could slow disease progression and improve lung function in people with moderate IPF.  Interim results showed that compared to placebo, those randomised to the triple therapy had greater mortality (11% versus 1%), more hospitalisations (29% versus 8%), and more serious adverse events (31% versus 9%), with no difference in lung function. 

The report states that this combination therapy is currently used widely in patients with IPF, but has not previously been compared as the triple therapy to placebo in a clinical trial.  Anyone taking this combination is asked to speak to their healthcare provider and not simply stop taking their medicines; the results apply to patients with well-defined IPF and not to those taking a combination of these drugs for other lung diseases or conditions. 

The other two study arms - comparing NAC alone to placebo alone - will continue enrolling and following their participants, and this part of the PANTHER-IPF study is expected to be completed by late 2013.  The researchers will continue to analyse the data in an attempt to understand why this particular combination may be detrimental to people with IPF.