Inhaled pirfenidone solution (AP01) for IPF: a randomised, open-label, dose-response trial

Abstract

Introduction: Oral pirfenidone reduces lung function decline and mortality in patients with idiopathic pulmonary fibrosis (IPF). Systemic exposure can have significant side effects, including nausea, rash, photosensitivity, weight loss and fatigue. Reduced doses may be suboptimal in slowing disease progression.

Methods: This phase 1b, randomised, open-label, dose-response trial at 25 sites in six countries (Australian New Zealand Clinical Trials Registry (ANZCTR) registration number ACTRN12618001838202) assessed safety, tolerability and efficacy of inhaled pirfenidone (AP01) in IPF. Patients diagnosed within 5 years, with forced vital capacity (FVC) 40%-90% predicted, and intolerant, unwilling or ineligible for oral pirfenidone or nintedanib were randomly assigned 1:1 to nebulised AP01 50 mg once per day or 100 mg two times per day for up to 72 weeks.

Results: We present results for week 24, the primary endpoint and week 48 for comparability with published trials of antifibrotics. Week 72 data will be reported as a separate analysis pooled with the ongoing open-label extension study. Ninety-one patients (50 mg once per day: n=46, 100 mg two times per day: n=45) were enrolled from May 2019 to April 2020. The most common treatment-related adverse events (frequency, % of patients) were all mild or moderate and included cough (14, 15.4%), rash (11, 12.1%), nausea (8, 8.8%), throat irritation (5, 5.5%), fatigue (4, 4.4%) and taste disorder, dizziness and dyspnoea (three each, 3.3%). Changes in FVC % predicted over 24 and 48 weeks, respectively, were -2.5 (95% CI -5.3 to 0.4, -88 mL) and -4.9 (-7.5 to -2.3,-188 mL) in the 50 mg once per day and 0.6 (-2.2 to 3.4, 10 mL) and -0.4 (-3.2 to 2.3, -34 mL) in the 100 mg two times per day group.

Discussion: Side effects commonly associated with oral pirfenidone in other clinical trials were less frequent with AP01. Mean FVC % predicted remained stable in the 100 mg two times per day group. Further study of AP01 is warranted.

Trial registration number: ACTRN12618001838202 Australian New Zealand Clinical Trials Registry.

Keywords: cough/mechanisms/pharmacology; idiopathic pulmonary fibrosis.

Conflict of interest statement

Competing interests: NC received a grant from Boehringer Ingelheim and consulting fees from Boehringer Ingelheim, Carrick, Redex, UCB, and Novartis; speaker fees and travel sponsorship from Boehringer Ingelheim and Roche; and payment for participation on data monitoring/advisory board from Boehringer Ingelheim. IG reports consulting fees from Amplia, Ad Alta and Accendatech; speaking fees from Boehringer Ingelheim; and payment for participation in a safety review committee from Accendatech. TJC reports receiving grants/contracts from Boehringer Ingelheim, Roche, Bristol Myers Squibb, Biogen, Galapagos and Avalyn Pharma; speaker’s honoraria from Boehringer Ingelheim and Roche; and payment for participation on data safety monitoring/advisory board from Boehringer Ingelheim, Roche, Bristol Myers Squibb and Promedior. EJ received honoraria for lectures from Boehringer Ingelheim, Roche, AstraZeneca, MDS and Chiesi; sponsored travel to meetings from Boehringer Ingelheim and Roche; and payment for participation in advisory boards from Boehringer Ingelheim, Roche, AstraZeneca, Novartis, MDS, Berlin-Chemie and Chiesi. MW reports payments to her institution from Boehringer Ingelheim, Roche, the Netherlands Organisation for Health Research and Development, the Dutch Lung Foundation, the Dutch Pulmonary Fibrosis Patient Association, the Thorax Foundation, ErasmusMC and Sarcoidoisis.nl. Consulting fees were paid to her institution by Boehringer Ingelheim, Roche, Galapagos, Bristol Myers Squibb, Galecto and Respivant; honoraria were paid to her institution by Boehringer Ingelheim, Roche and Novartis. MW received sponsored travel from Boehringer Ingelheim and Roche, and her institution received payment for her participation in data safety monitoring/advisory board from Savara and Galapagos. CG received consulting fees from Avalyn Pharma. GR reports receiving support from Avalyn Pharma for consulting and for chairing the Data Safety Monitoring Board during the conduct of the study; personal and consulting fees from Boehringer Ingelheim, Respivant and Roche; grants from the NIH; and consulting fees from Bellerophon Therapeutics, Biogen, Bristol Myers Squibb, Fibrogen, Nitto, Promedior, Respivant and Veracyte.

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