Effect of baseline FVC on preservation of lung function with BIBF 1120: Results from the TOMORROW trial

Background: BIBF 1120 is an inhibitor of tyrosine kinase receptors involved in the progression of lung fibrosis. Methods: The efficacy and safety of 50 mg, 100 mg, 200 mg and 300 mg daily doses of BIBF 1120 were evaluated in 428 patients diagnosed with IPF in a Phase 2 randomized, double-blind placebo (PBO)-controlled trial. Subgroup analyses of the annual rate of decline in forced vital capacity (FVC) by baseline lung function were carried out to evaluate the impact of stage of disease on the effect of BIBF 1120. Results: Baseline FVC was similar in all groups (mean: 2.8 L; 81.3% predicted). The annual rate of decline in FVC was -0.060 L/year with BIBF 1120 300 mg vs -0.190 L/year with PBO (p=0.014; closed-testing multiplicity-corrected: p=0.064). Patients with baseline FVC ≥70% of predicted value showed almost no FVC decline with BIBF 1120 300 mg (-0.010 L/year [n=57] compared with -0.186 L/year in the PBO group [n=61]; p=0.004). However, there were no significant differences in FVC decline in patients with baseline FVC Conclusion: The effects of IPF treatment may be more easily demonstrable in patients with FVC values closer to predicted values.