Idiopathic pulmonary fibrosis is a condition where
the lungs are damaged and replaced by scar tissue, which impedes adequate air
exchange. Lung transplantation is done for some cases.
Mild cases are treated either with a single drug,
two-drug regimen or three-drug regimen. Many patients are treated with the
three-drug regimen, despite absence of clear-cut benefits of the same.
A study compared the use of three drugs prednisone,
azathioprine, and N-acetylcysteine in patients with mild-to-moderate pulmonary
fibrosis, with the use of either a single drug N-acetylcysteine or placebo. The
researchers reported the results of one part of the study, comparison of
three-drug use with that of placebo in a paper published in the New England Journal of Medicine
The analysis was carried out on data obtained from
77 patients on the combination therapy and 78 patients on placebo. The number
of patients who discontinued the three drugs by the 60th
much more than the number of patients who discontinued placebo.
The patients were checked at baseline, and at 4, 15,
30, 45, and 60 weeks of treatment. During
the study, it was found that patients on the three-drug regimen had more number
of deaths (8 vs. 1), hospitalizations (23 vs. 7) and serious adverse effects
(24 vs. 8) as compared to the placebo group
. In addition, the three-drug
regimen did not appear to provide much benefit as compared to placebo. Hence,
it was decided to discontinue the regimen in this group.
The study does have some
limitations. For instance, the treatment duration with three drugs may have
been too short to register any benefits. The exact cause of deaths and hospitalizations
were not recorded; in some cases, hospitalizations may have been for an
thus suggest that it may currently not be advisable to use the three-drug
regimen for the treatment of idiopathic pulmonary fibrosis
Prednisone, Azathioprine, and N-Acetylcysteine for Pulmonary Fibrosis;
Idiopathic Pulmonary Fibrosis Clinical Research Network; N Engl J Med 2012;