Zileuton for the Treatment of Idiopathic Pulmonary Fibrosis

Inclusion Criteria: Diagnosis of idiopathic pulmonary fibrosis Taking < 15 mg prednisone for at least 30 days prior to screening Age 35-80, inclusive Able to understand a written informed consent and comply with the study protocol Exclusion Criteria: Significant environmental exposure Diagnosis of collagen vascular disease Evidence of active infection Clinically significant cardiac disease Myocardial infarction, coronary artery bypass or angioplasty within 6mo Unstable angina pectoris Congestive heart failure requiring hospitalization within 6 months Uncontrolled arrhythmia Poorly controlled or severe diabetes mellitus Pregnancy or lactation Women of childbearing potential not using a medically approved means of contraception (i.e. oral contraceptives, intrauterine devices, diaphragm, Norplant) Current enrollment in another experimental protocol Physiologic Criteria: FEV1/FVC < 0.60 Laboratory Criteria: Total bilirubin > 1.5 X upper limit normal AST or ALT > 3X upper limit normal Alkaline phosphatase > 3X upper limit normal White blood cell count < 2,500/mm3 Hematocrit < 30% Platelets < 100,000/mm3 Prothrombin time INR > 1.5