Efficacy and safety of pirfenidone according to clinical trials

Abstract

The results of clinical studies on the use of pirfenidone in idiopathic pulmonary fibrosis (IPF) are presented. The purpose of this study was to analyze the effectiveness and safety of pirfenidone in IPF according to clinical studies published in the scientific literature. IPF occupies an important place in the structure of interstitial lung diseases. Currently, IPF is understood as a condition in which there is chronic progressive fibrotic interstitial aseptic pneumonia of unknown etiology, quickly leading to disability and death. The antifibrotic drug pirfenidone has been approved by the EMA and FDA for use in patients with IPF. The clinical efficacy and safety of pirfenidone have been demonstrated in randomized clinical trials. When using pirfenidone, there were 47.9 % fewer patients with an absolute decrease in FVC ≥10 % or who died, and 132.5 % more patients with no decrease in FVC (p <0.001). In addition, the pirfenidone group had significantly better 6-minute walk test scores (p=0.04) and significantly improved progression-free survival (p<0.001). Long-term use of pirfenidone (up to 72 weeks) significantly reduced the rate of decline in FVC, prevented a reduction in distance traveled in the 6-minute walk test, and increased the time until signs of disease progression appeared compared with placebo. Pirfenidone demonstrated a good safety profile; in most cases, adverse effects were mild, disappeared when the drug dose was reduced, and had no adverse long-term consequences. As a result of a generalized analysis of adverse events recorded in the CAPACITY, ASCEND, and RECAP studies, it was found that long-term (maximum duration was 9.9 years) treatment with pirfenidone was accompanied by nausea in 37.6 % of cases, diarrhea in 28.1 %, dyspepsia — in 18.4 %, vomiting — in 15.9 %, and skin rashes — in 25.0 %.