Negative impact of anorexia and weight loss during prior pirfenidone administration on subsequent nintedanib treatment in patients with idiopathic pulmonary fibrosis

Current clinical practice guidelines for idiopathic pulmonary fibrosis (IPF) conditionally recommend use of pirfenidone and nintedanib. However, an optimal treatment sequence has not been established, and the data of treatment sequence from pirfenidone to nintedanib are limited. This study aimed to evaluate safety, tolerability and efficacy of nintedanib switched from pirfenidone in patients with IPF.

Thirty consecutive IPF cases, which discontinued pirfenidone because of a decline in forced vital capacity (FVC) or intolerable adverse event (AE), and newly started nintedanib (150 mg twice daily) from September 2015 to August 2017 (switch-group) were retrospectively reviewed. Subsequently, we compared the characteristics, treatment status, and AEs between the switch-group and other 64 IPF patients newly started nintedanib during the same period without any prior anti-fibrotic treatment (pirfenidone-naïve group).

In the switch group, median age, body weight, body mass index (BMI), and %FVC were 72 years old, 54.9 kg, 21.0 kg/m², and 52.9%, respectively. Most common AE of nintedanib was aspartate aminotransferase/alanine aminotransferase elevation (71.9%), followed by anorexia (46.7%) and diarrhea (46.7%); whereas, anorexia (63.3%) and ≥ 5% weight loss from baseline (56.7%) were common during pirfenidone administration. Sixteen patients (53.3%) discontinued nintedanib within 6 months (early termination). Multivariate logistic regression analysis revealed a significant association between low BMI and early nintedanib termination in the switch-group (p = 0.0239). Nintedanib suppressed FVC decline as compared with that during administration period of pirfenidone in 70% of the patients who could undergo lung function before and after switching to nintedanib. The incidence of early termination of nintedanib was higher in the switch-group than in the pirfenidone-naïve group, whereas body-weight, BMI, absolute FVC values, and %FVC were significantly lower in the switch-group (just before nintedanib initiation) than in the pirfenidone-naïve group. Nintedanib-induced anorexia was more frequent and severer in the switch-group than in the pirfenidone-naïve group, but no significant differences were observed in terms of other AEs.

A high incidence of early termination of nintedanib was noted when patients were switched from pirfenidone. Anorexia and weight loss during prior pirfenidone administration may increase the rate of the early termination of subsequent nintedanib treatment.