Senicapoc in Patients with Idiopathic Pulmonary Fibrosis or Other Progressive Fibrotic Interstitial Lung Diseases:...

Background/Objectives: Idiopathic pulmonary fibrosis (IPF) and other progressive fibrotic interstitial lung diseases (F-ILD) are characterised by progressive loss of lung function, worsening symptoms, and poor prognosis. Current antifibrotic therapies slow disease progression but do not arrest or reverse fibrosis and are frequently associated with adverse effects. Senicapoc, a selective KCa3.1 channel inhibitor, has shown antifibrotic effects in preclinical models, human lung myofibroblasts, and ex vivo human lung tissue. This study aims to determine whether senicapoc reduces the rate of decline in forced vital capacity (FVC) over 26 weeks, compared with placebo, in patients with IPF or other progressive F-ILD, while also characterising safety and tolerability. Methods: This is an investigator-initiated, prospective, randomised, double-blind, placebo-controlled, multicentre phase II trial. Adults with IPF or other F-ILD with documented progression despite optimised antifibrotic management according to standard care and individual tolerability will be randomised 1:1 to receive senicapoc 30 mg once daily or a matching placebo for 26 weeks in addition to standard care. The primary outcome is the rate of decline in FVC over 26 weeks. Secondary outcomes include changes in diffusion capacity, 6 min walk distance, dyspnoea, health-related quality of life, adverse events, and senicapoc plasma concentrations, with mortality and exacerbations assessed as exploratory outcomes. The planned sample size is 140 participants. The primary analysis will be conducted in the intention-to-treat population using a linear mixed-effects model for repeated measurements. Results: No results are available, as this article describes the study protocol. Conclusions: This study will provide proof of concept for the efficacy, safety, and tolerability of senicapoc in progressive fibrotic interstitial lung disease. If successful, it will support further clinical development of KCa3.1 inhibition as a novel antifibrotic strategy.