Study of ABBV-142 to Assess Adverse Events and Change in Disease Activity in Adult Participants With Idiopathic Pulmonary Fibrosis

Idiopathic Pulmonary Fibrosis (IPF) is a rare, long-lasting lung disease that causes scarring of lung tissue, shortness of breath, and loss of lung function. IPF leads to significant loss of quality of life and shortened lifespan. This study is a platform study evaluating different types of treatments in patients with IPF. A platform study is a type of study that uses a single master protocol to evaluate different study treatments allowing for new study treatments or substudies to be added or closed over time. The main goals of the study are to evaluate the safety, tolerability (the degree to which the adverse symptoms can be handled by the patients during the study) and efficacy (how well study treatment works) of the study treatments, including ABBV-142 in Substudy 1 (SS1). ABBV-142 is an investigational drug being developed for the treatment of IPF. In SS1, participants will be randomly assigned to one of the 2 groups to receive either ABBV-142 or a matching placebo. This study is "double-blind", meaning that neither the participants nor the study doctors know who is given which study treatment. Approximately 165 adult participants with IPF will be enrolled in approximately 125 sites across the world. Participants will receive ABBV-142 or matching placebo for 52 weeks during the double-blind treatment period. Eligible participants may receive ABBV-142 for 52 weeks in open-label treatment period. All participants will be followed for 120 days. There may be higher treatment burden for participants in this trial compared to their standard of care. Participants will attend regular visits during the study at a hospital or clinic. The effect of the treatment will be checked by medical assessments, blood tests, checking for side effects and completing questionnaires.