C39-24 Trajectories of Forced Vital Capacity and Time to Outcomes Among Patients With Idiopathic Pulmonary Fibrosis

Abstract Rationale Idiopathic pulmonary fibrosis (IPF) is a severe form of chronic interstitial lung disease and is associated with high mortality. Lung function measured with forced vital capacity percent predicted (FVCpp) is a key indicator of the status of IPF progression. Patients with different FVCpp trajectories may have different prognosis. The objectives of this study were to characterize FVCpp trajectories overall, and among clusters of patients with similar FVCpp trajectories, and to describe their corresponding real-word terminal outcomes. Methods Adults with IPF were identified from the Truveta platform (1/2015-5/2025). Patients were required to have ≥2 IPF diagnoses ≤365 days apart. The first IPF diagnosis was the index date. The follow-up period spanned the index date until the end of clinical activity or real-world terminal outcome (i.e., lung transplant or death). Patients had a baseline FVCpp value during the 12 months before or up to 60 days after the index date and ≥1 FVCpp value during the follow-up period, after the baseline value. Patients were naïve to antifibrotic agents before the index date; subsequent initiation or use of antifibrotic agents was not required after the index date. Clusters of patients with similar longitudinal patterns of FVCpp were identified using flexible mixture modeling. Time to terminal outcomes was described both overall and for clusters using Kaplan-Meier models. Results A total of 1,097 patients were identified (mean age: 73.9 years old; female: 35.7%; mean baseline FVCpp: 77.3; mean follow-up time: 36.5 months; FVCpp decline: 0.86 percentage point per year). Antifibrotic agents were initiated in 59.3% of the patients. Two clusters were identified. Cluster 1 included 53.2% of patients (mean age: 74.7 years old; female: 30.0%; mean baseline FVCpp: 91.3; FVCpp decline: 0.19 percentage point per year). Cluster 2 included 46.8% of patients (mean age: 73.0 years old; female: 42.3%; mean baseline FVCpp: 61.4; FVCpp decline: 0.80 percentage point per year). At 3 years, 77.8% (overall), 84.0% (cluster 1), and 71.1% (cluster 2) did not experience terminal outcomes. Median time to terminal outcomes was 6.1 years (overall), not reached (cluster 1) and 5.5 years (cluster 2). Conclusions These results are suggestive that the progression to terminal outcomes may differ by FVCpp at the time of IPF diagnosis, highlighting unmet needs in IPF monitoring and management. This abstract is funded by: Boehringer Ingelheim Pharmaceuticals, Inc.