Phase 2, Double-Blind, Placebo-controlled Trial of a c-Jun N-Terminal Kinase Inhibitor in Idiopathic Pulmonary Fibrosis.

Idiopathic pulmonary fibrosis is a fatal and progressive disease with limited treatment options. We sought to assess the efficacy and safety of CC-90001, an oral inhibitor of c-Jun N-terminal kinase 1, in patients with idiopathic pulmonary fibrosis. In a Phase 2, randomized (1:1:1), double-blind, placebo-controlled study (ClinicalTrials.gov ID: NCT03142191), patients received CC-90001 (200 or 400 mg) or placebo once daily for 24 weeks. Background antifibrotic treatment (pirfenidone) was allowed. The primary endpoint was change in the percentage of predicted FVC (ppFVC) from baseline to Week 24; secondary endpoints included safety. In total, 112 patients received at least one dose of study drug. The study was terminated early because of a strategic decision made by the sponsor. Ninety-one patients (81%) completed the study. The least-squares mean changes from baseline in ppFVC at Week 24 were -3.1% (placebo), -2.1% (200 mg), and -1.0% (400 mg); the differences compared with placebo were 1.1% (200 mg; 95% confidence interval: -2.1, 4.3;  = 0.50) and 2.2% (400 mg; 95% confidence interval: -1.1, 5.4;  = 0.19). Adverse event frequency was similar in patients in the combined CC-90001 arms versus placebo. The most common adverse events were nausea, diarrhea, and vomiting, which were more frequent in patients in CC-90001 arms versus placebo. Fewer patients in the CC-90001 arms than in the placebo arm experienced cough and dyspnea. Treatment with CC-90001 over 24 weeks led to numerical improvements in ppFVC in patients with idiopathic pulmonary fibrosis compared with placebo. CC-90001 was generally well tolerated, which was consistent with previous studies. Clinical trial registered with www.clinicaltrials.gov (NCT03142191).