Pirfenidone in Idiopathic Pulmonary Fibrosis “RECAP-itulating Safety into the Real World”

duced respiratory-related hospitalizations indicating a beneficial impact on acute exacerbations of the disease [8] . Major drug-related side effects were nausea, respiratory tract infections, photosensitivity, and diarrhea [9] . Although phase 3 clinical trials set the basis for marketing authorization approval and commercial availability of the drug, they present with inherent limitations on generalizability of the results since they cannot map risks in the real-world setting. Moreover, thorough knowledge that we have about well-established therapeutic agents is acquired after the drug has been approved and marketed and thousands of patients have been exposed to it. In this issue of Respiration , Costabel et al. [10] report longitudinal safety outcomes of the RECAP study, a large simple trial in a cohort of patients with IPF who had previously completed a phase 3 randomized controlled trial. The study enrolled 1,058 patients who had been followed up for almost 5 years. Almost all patients reported at least one treatment-related adverse event. The majority of those were associated with disease progression (33.6%) and respiratory tract infections (52.5%). Cough and dyspnea were also reported in about 1/3 of participants. On the other hand, the most frequent adverse reactions were Idiopathic pulmonary fibrosis (IPF) is a devastating chronic lung disease that is characterized by progressive lung scarring, ultimately leading to respiratory failure and death within 2.5–3 years of diagnosis [1] . With a gradually increasing incidence, its clinical course being largely unpredictable and the pathogenesis elusive, IPF treatment still represents a major bottleneck for clinicians and researchers [2] . Pirfenidone was the first drug to be approved for the treatment of IPF in the European Union [3] . Pirfenidone is a pleiotropic molecule with antifibrotic, anti-inflammatory and antioxidant properties. It has been demonstrated to inhibit major antifibrotic signaling pathways including those of transforming growth factor-β1, fibroblast growth factor and interleukin-1β [4] . Importantly, pirfenidone has been clinically evaluated and has shown beneficial effects in patients with IPF in 5 randomized controlled trials comprising an overall of 1,710 patients [5–7] . In particular, it was shown that pirfenidone was able to slow down the annual functional decline and reduce the risk of death at 1 year by 48% in a prespecified pooled analysis including data from 3 independent cohorts of patients with IPF [5, 6] . In addition, a recent study showed that pirfenidone significantly rePublished online: September 5, 2017