A randomized double blind, placebo controlled phase 2 trial of BIIL 284 BS (an LTB4 receptor antagonist) for the treatment of lung disease in children and adults with cystic fibrosis

Background: Airway inflammation, mediated in part by LTB4, contributes to lung destruction in patients with cystic fibrosis (CF). LTB4-receptor inhibition may reduce airway inflammation. We report the results of a randomized, double-blind, placebo-controlled study of the efficacy and safety of the leukotriene B-4 (LTB4)-receptor antagonist BILL 284 BS in CF patients. Methods: CF patients aged >= 6 years with mild to moderate lung disease were randomized to oral BIIL 284 BS or placebo once daily for 24 weeks. Co-primary endpoints were change in FEV1 and incidence of pulmonary exacerbation. Results: After 420 (155 children, 265 adults) of the planned 600 patients were randomized, the trial was terminated after a planned interim analysis revealed a significant increase in pulmonary related serious adverse events (SAEs) in adults receiving BIIL 284 BS. Final analysis revealed SAEs in 36.1% of adults receiving BIIL 284 BS vs. 21.2% receiving placebo (p = 0.007), and in 29.6% of children receiving BILL 284 BS vs. 22.9% receiving placebo (p = 0.348). In adults, the incidence of protocol-defined pulmonary exacerbation was greater in those receiving BILL 284 BS than in those receiving placebo (33.1% vs. 18.2% respectively; p = 0.005). In children, the incidence of protocol-defined pulmonary exacerbation was 19.8% in the BIIL 284 BS arm, and 25.7% in the placebo arm (p = 0.38). Conclusions: While the cause of increased SAEs and exacerbations due to BIIL 284 BS is unknown, the outcome of this trial provides a cautionary tale for the administration of potent anti-inflammatory compounds to individuals with chronic infections, as the potential to significantly suppress the inflammatory response may increase the risk of infection-related adverse events. (C) 2014 European Cystic Fibrosis Society. Published by Elsevier B.V. All rights reserved.