Lasky, Joseph A.

Abstract Rationale Idiopathic pulmonary fibrosis (IPF) is a progressive lung disease with no known efficacious therapy. Imatinib is a tyrosine kinase inhibitor with potential efficacy to treat fibrotic lung disease. Objectives To investigate the safety and clinical effects of imatinib in patients with IPF. Methods We studied 119 patients in an investigator-initiated, multicenter, multinational, double-blind clinical trial to receive imatinib or placebo for 96 weeks. Measurements and Main Results Over 96 weeks of follow-up, imatinib did not differ significantly from placebo (log rank P = 0.89) for the primary endpoint defined as time to disease progression (10% decline in percent predicted FVC from baseline) or time to death. There was no effect of imatinib therapy on change in FVC at 48, 72, or 96 weeks (P ≥ 0.39 at all time points) or change in diffusing capacity of carbon monoxide at 48, 72, or 96 weeks (P ≥ 0.26 at all time points). Change in resting PaO2 favored imatinib therapy at 48 weeks (P = 0.005) but not at 96 weeks (P = 0.074). During the 96-week trial there were 8 deaths in the imatinib group and 10 deaths in the placebo group (log rank test P = 0.64). Thirty-five (29%) patients discontinued the study without reaching the primary endpoint (imatinib, 32%; placebo, 27%; P = 0.51). Serious adverse events (SAEs) were not more common in the imatinib group (imatinib, 18 SAEs in 17 patients; placebo, 19 SAEs in 18 patients). Conclusions In a randomized, placebo-controlled trial of patients with mild to moderate IPF followed for 96 weeks, imatinib did not affect survival or lung function. Clinical trial registered with www.clinicaltrials.gov (NCT00131274).

Abstract Rationale An efficacious medical therapy for idiopathic pulmonary fibrosis (IPF) remains elusive. Objectives To explore the efficacy and safety of etanercept in the treatment of IPF. Methods This was a randomized, prospective, double-blind, placebo-controlled, multicenter exploratory trial in subjects with clinically progressive IPF. Primary endpoints included changes in the percentage of predicted FVC and lung diffusing capacity for carbon monoxide corrected for hemoglobin (DlCOHb) and change in the alveolar to arterial oxygen pressure difference P(a–a)O2 at rest from baseline over 48 weeks. Measurements and Main Results Eighty-eight subjects received subcutaneous etanercept (25 mg) or placebo twice weekly as their sole treatment for IPF. No differences in baseline demographics and disease status were detected between treatment groups; the mean time from first diagnosis was 13.6 months and mean FVC was 63.9% of predicted. At 48 weeks, no significant differences in efficacy endpoints were observed between the groups. A nonsignificant reduction in disease progression was seen in several physiologic, functional, and quality-of-life endpoints among subjects receiving etanercept. There was no difference in adverse events between treatment groups. Conclusions In this exploratory study in patients with clinically progressive IPF, etanercept was well tolerated. Although there were no differences in the predefined endpoints, a decreased rate of disease progression was observed on several measures. Further evaluation of TNF antagonists in the treatment of IPF may be warranted. Clinical trial registered with www.clinicaltrials.gov (NCT 00063869).

Abstract The natural history of idiopathic pulmonary fibrosis (IPF) has been characterized as a steady, predictable decline in lung function over time. Recent evidence suggests that some patients may experience a more precipitous course, with periods of relative stability followed by acute deteriorations in respiratory status. Many of these acute deteriorations are of unknown etiology and have been termed acute exacerbations of IPF. This perspective is the result of an international effort to summarize the current state of knowledge regarding acute exacerbations of IPF. Acute exacerbations of IPF are defined as acute, clinically significant deteriorations of unidentifiable cause in patients with underlying IPF. Proposed diagnostic criteria include subjective worsening over 30 days or less, new bilateral radiographic opacities, and the absence of infection or another identifiable etiology. The potential pathobiological roles of infection, disordered cell biology, coagulation, and genetics are discussed, and future research directions are proposed.