Persistence, safety, and costs of antifibrotic treatment for idiopathic pulmonary fibrosis (IPF): a US Veterans Health Administration (VHA) claims study

Introduction: The antifibrotics nintedanib and pirfenidone are the only 2 agents approved for IPF, but few studies have examined their real-world utilization and outcomes. Aims & Objectives: To determine antifibrotic treatment persistence in VHA patients (pts) and assess incident adverse events (AEs), healthcare resource utilization (HCRU), and costs in persistent vs nonpersistent pts. Methods: Eligible adults had ≥1 antifibrotic pharmacy claim on/after the first IPF diagnosis (10/1/2015–9/30/2018; index date=first treatment date) and continuous coverage for ≥12 months before (baseline) and after (follow-up) the index date. Persistent pts had a ≤45 d gap between antifibrotic refills without switching to non-index treatment during follow-up. Pt characteristics, AEs, and per pt per month (PPPM) HCRU and costs were analyzed descriptively and compared in persistent vs nonpersistent pts. Results: Of 4,459 VHA pts with IPF, 850 (19%) received antifibrotics; mean time from diagnosis to treatment was 168 d. 285 pts (34%) were persistent; they were younger (72 y vs 74 y) with a higher frequency of pulmonary hypertension (12% vs 7%) and lower rates of abdominal pain, dizziness, and headache vs nonpersistent pts. During follow-up, lower AE incidence proportion but significantly higher HCRU and costs were found in persistent vs nonpersistent pts ($18,698 vs $9,007; p<0.0001). Conclusions: These data suggest that substantial unmet needs remain among veterans with newly diagnosed IPF, including greater utilization of existing antifibrotics and more tolerable treatment options. Future study of the cost drivers among treated pts is warranted.