Clinical Research Directory

Inclusion Criteria: * Ability to understand and sign written informed consent. * The diagnosis time of IPF before enrollment was less than 5 years. * Combination of High Resolution Computerized Tomography (HRCT) pattern, and if available surgical lung biopsy pattern, as assessed by central reviewers, are consistent with diagnosis of IPF. * Dlco (corrected for Hb): 30%-90% predicted of normal. * FVC\>= 50% predicted of normal. Exclusion Criteria: * Forced expiratory volume in one second (FEV1)/FVC ratio \<0.7 after administration of bronchodilator at Screening * Expected to receive a lung transplant within 1 year from randomization or, for patients at sites in the United States, on a lung transplant waiting list at randomization. * Known explanation for interstitial lung disease * History of asthma or chronic obstructive pulmonary disease * Active infection * Ongoing IPF treatments including investigational therapy, immunosuppressants, and cytokine modulating agents * History of unstable or deteriorating cardiac or pulmonary disease (other than IPF) within the previous 6 months