The National Heart, Lung, and Blood Institute has halted the triple-drug therapy arm of a treatment trial for idiopathic pulmonary fibrosis because of poor outcomes, according to a statement issued by the National Institutes of Health.
Interim data from the study indicated that patients with idiopathic pulmonary fibrosis (IPF) who received a combined therapy of prednisone, azathioprine, and N-acetylcysteine (NAC) had no improvement in lung function, compared with a placebo group. In addition, compared with the placebo group, the treatment group had significantly higher rates of death (11% vs. 1%), hospitalization (29% vs. 8%), and serious adverse events (31% vs. 9%).
The study, known as PANTHER-IPF (Prednisone, Azathioprine, and N-acetylcysteine: A Study That Evaluates Response in Idiopathic Pulmonary Fibrosis), was designed to evaluate the effectiveness of a triple-therapy regimen in slowing disease progression and improving lung function in patients with moderate to severe IPF. The average age of the study participants at enrollment was 68 years.
"This combination therapy is widely used in patients with IPF but has not previously been studied in direct comparison to a placebo for all three drugs," Dr. Susan B. Shurin, acting director of the NHLBI, noted in a statement.
Patients in the other two treatment arms who are receiving NAC alone or a placebo will continue with their designated treatment protocols, which are scheduled to last up to 60 weeks, according to the NIH statement.
The researchers began enrolling patients in 2009. Completion of the first phase of the study with the two remaining treatment arms is expected by 2013. More details about the trial are available online.
The study was supported by National Institutes of Health and the Cowlin Family Fund at Chicago Community Trust. The NAC and matching placebo treatments were donated by Zambon; study funds were used to purchase the prednisone, azathioprine, and matching placebos.