Antifibrotic Drug Use in Patients With IPF: Data From the IPF-PRO Registry

Rationale Two antifibrotic medications, nintedanib and pirfenidone, have been approved for the treatment of idiopathic pulmonary fibrosis (IPF) in the US. Few data have been published on the use of these medications in clinical practice. Objective To investigate patterns of use of antifibrotic medications in the US. Methods The IPF-PRO Registry, a multicenter US registry, has enrolled patients with IPF that was diagnosed or confirmed at the enrolling center in the past 6 months. Data from patients enrolled from 5 June 2014 to 4 March 2018 were used to determine antifibrotic medication use ("treatment") in the enrollment window and a follow-up window approximately 6 months later. Associations between patient characteristics and treatment status were tested using logistic regression. Results Overall, 551 of 782 eligible patients (70.5%) were treated in the enrollment window. Younger age, lower FVC % predicted, oxygen use with activity, worse self-rated health based on the Short Form-12 (SF-12) or St George's Respiratory Questionnaire score, referral to the enrolling center by a pulmonologist, use of lung biopsy in diagnosis, and carrying a diagnosis of IPF to the enrolling center were associated with being treated. Among 534 patients treated at enrollment who had follow-up data, 94.0% remained treated in follow-up. Better self-rated health based on the SF-12 mental component score or EuroQoL score, and not using oxygen with activity at enrollment, were associated with continuing treatment in follow-up. Among 172 patients who were untreated at enrollment and had follow-up data, 29.7% started treatment in follow-up. Lower DLco % predicted, a family history of ILD, a history of sleep apnea, and a definite diagnosis of IPF at enrollment were associated with starting treatment in follow-up. Conclusions The majority of patients in the IPF-PRO Registry were receiving an approved medication for IPF at enrollment. Treatment at enrollment was associated with greater disease severity, more compromised quality of life and the use of oxygen with activity. Clinical trial registered with ClinicalTrials.gov (NCT01915511).