Nintedanib Treatment for Idiopathic Pulmonary Fibrosis Patients Who Have Been Switched from Pirfenidone Therapy: A Retrospective Case Series Study

Tolerability and efficacy of switching anti-fibrotic treatment from nintedanib to pirfenidone for idiopathic pulmonary fibrosis

BACKGROUND

In real-world studies, the rate of discontinuation of nintedanib (NT) varies from 4% to 53%. Switching anti-fibrotic treatment in patients with idiopathic pulmonary fibrosis (IPF) has not been adequately investigated, and data on the tolerability and efficacy of changes in anti-fibrotic treatment is limited in clinical practice.

OBJECTIVE

To identify factors associated with poor continuation of NT, efficacy and predictors of deterioration after switching from NT to pirfenidone (PFD) in patients with IPF.

SUBJECTS AND METHODS

One hundred and seventy patients with IPF in whom NT was introduced between April 2017 and March 2022 were included to investigate NT continuation status and the effect of switching to PFD.

RESULTS

A total of 123 patients (72.4%) continued NT for 1 year and had a significantly higher %forced vital capacity (FVC) at NT introduction than those who discontinued within 1 year (80.9% ± 16.3% vs. 71.9% ± 22.1%, P = 0.004). The determinant of poor NT continuation was the high GAP stage. On the other hand, 28 of 36 patients who discontinued NT because of disease progression switched to PFD. Consequently, FVC decline was suppressed before and after the change. The predictor of deterioration after the switch was a lower body mass index.

CONCLUSIONS

In patients with IPF, early NT introduction increased continuation rates, and switching to PFD was effective when patients deteriorated despite initial NT treatment.

The Impact of Switching to a Second Antifibrotic in Patients With Idiopathic Pulmonary Fibrosis: A Retrospective Multicentre Study From the EMPIRE Registry

INTRODUCTION

Most patients with idiopathic pulmonary fibrosis (IPF) treated with antifibrotics (AF) have progressive disease despite treatment. A switch of AF may improve survival, but evidence from randomised controlled trials is missing. We aimed to evaluate the efficacy of an AF switch on survival and FVC decline in patients from the European MultiPartner IPF registry (EMPIRE).

METHODS

The study included 612 patients who discontinued the first antifibrotic therapy. Patients were grouped and analysed from two perspectives: (1) whether they had received a second antifibrotic treatment after the discontinuation of the first therapy, and (2) a reason for discontinuation of the first AF - "lack of efficacy" (LE) and "intolerance" (INT).

RESULTS

While 263 (43%) of 612 patients received no second AF ("non-switched"), 349 (57%) patients switched. Overall survival was higher in patients who received a second AF (median 50 vs. 29 months; adjusted HR 0.64, P=0.023). Similarly, the annual FVC decline was significantly reduced in switched patients: -98ml/y in switched and -172ml/y in non-switched patients (P=0.023), respectively. The switched patients had similar risk for mortality in both LE and INT groups (adjusted HR 0.95, P=0.85). The high impact of switching on survival was demonstrated in LE patients (adjusted HR 0.27, P<0.001).

CONCLUSION

The patients without a second AF had significantly shorter overall survival. Our analysis suggests the importance of switching patients with an ineffective first AF therapy to a second AF therapy.

A Narrative Review of Real-World Data on the Safety of Nintedanib in Patients with Idiopathic Pulmonary Fibrosis

Nintedanib is a tyrosine kinase inhibitor approved for the treatment of idiopathic pulmonary fibrosis (IPF) and other progressive fibrosing interstitial lung diseases. Placebo-controlled trials showed that the adverse event profile of nintedanib was characterised mainly by gastrointestinal events, particularly diarrhoea. We review the data from all published real-world studies of the safety of nintedanib in patients with IPF. These real-world data were consistent with the safety profile observed in clinical trials and described in the product label. The most common adverse events were diarrhoea, nausea and vomiting, but these infrequently led to permanent treatment discontinuation. Liver enzyme elevations were observed, supporting the recommendation for regular monitoring of liver enzymes, particularly in the first few months of treatment. Bleeding and cardiovascular adverse events were rarely reported. As in clinical trials, in real-world studies, reductions of the nintedanib dose, treatment interruptions and use of anti-diarrhoeal medications were frequently employed to manage adverse events. Few data are available on the use of nintedanib in patients who are elderly or have advanced disease, but there are some data to suggest a greater rate of treatment discontinuation in these patients. Effective management of adverse events associated with nintedanib is important to minimise their impact.

Transforming Growth Factor-β1 Regulates Peroxisomal Genes/Proteins via Smad Signaling in Idiopathic Pulmonary Fibrosis Fibroblasts and Transgenic Mouse Models

Idiopathic pulmonary fibrosis (IPF) is a chronic human disease with persistent destruction of lung parenchyma. Transforming growth factor-β1 (TGF-β1) signaling plays a pivotal role in the initiation and pathogenesis of IPF. As shown herein, TGF-β1 signaling down-regulated not only peroxisome biogenesis but also the metabolism of these organelles in human IPF fibroblasts. In vitro cell culture observations in human fibroblasts and human lung tissue indicated that peroxisomal biogenesis and metabolic proteins were significantly down-regulated in the lung of 1-month-old transgenic mice expressing a constitutively active TGF-β type I receptor kinase (ALK5). The peroxisome biogenesis protein peroxisomal membrane protein Pex13p (PEX13p) as well as the peroxisomal lipid metabolic enzyme peroxisomal acyl-coenzyme A oxidase 1 (ACOX1) and antioxidative enzyme catalase were highly up-regulated in TGF-β type II receptor and Smad3 knockout mice. This study reports a novel mechanism of peroxisome biogenesis and metabolic regulation via TGF-β1-Smad signaling: interaction of the Smad3 transcription factor with the PEX13 gene in chromatin immunoprecipitation-on-chip assay as well as in a bleomycin-induced pulmonary fibrosis model applied to TGF-β type II receptor knockout mice. Taken together, data from this study suggest that TGF-β1 participates in regulation of peroxisomal biogenesis and metabolism via Smad-dependent signaling, opening up novel strategies for the development of therapeutic approaches to inhibit progression of pulmonary fibrosis patients with IPF.

Tolerability and efficacy of second-line antifibrotics in patients with idiopathic pulmonary fibrosis

BACKGROUND

The antifibrotic drugs nintedanib and pirfenidone reduce disease progression in idiopathic pulmonary fibrosis (IPF) and have also shown to improve survival. Switching first-line antifibrotic drug may required in IPF due to disease progression or intolerable adverse effects. The aim of this study was to assess the safety and efficacy of second-line antifibrotic treatment in patients with IPF.

MATERIAL AND METHODS

This retrospective, multicenter study was conducted at three referral interstitial lung disease centers who received first-line antifibrotics more than one month and switched the treatment to a second-line antifibrotic agent during January 2016-June 2021. The drug's safety was evaluated based on the type of adverse effect. Disease progression was defined as an absolute decline in FVC of >10% within 12 months with or without radiological progression.

RESULTS

Among 629 consecutive patients with IPF, 66 patients switched antifibrotics. The median duration of antifibrotics was 13 (1-41) months prior to the switch, and 14 (2-42) months after the switch. The mean age was 70.6 ± 8.9 years and, median FVC (%) was 72.1 ± 18.7 at the initiation of first-line antifibrotics. The most common reason for the switch was disease progression (56%) followed by severe adverse effects (SAEs) (44%). SAEs were significantly less observed after the switch compared before the switch (43.9% vs12.1%, respectively, p < 0.001). Eighteen patients had adverse effects due to second-line antifibrotics. Among these patients, 10 had mild adverse effects and 8 had severe adverse effects. While there was no change in the FVC (%) values in 30.3% patients 12 months after the first-line antifibrotic treatment (before the switch), there was no change in the FVC (%) values in 40% patients at the end of 12 months after the switch. Fourteen patients (42.4%) who received antifibrotic treatment before the switch had more than 10% decline in FVC (%) at the end of 12 months. Eight patients (32.0%) had 10% or more decline in FVC (%) 12 months after the switch.

CONCLUSION

Patients with IPF who do not tolerate first-line antifibrotic treatment or those showing disease progression despite treatment, switching antifibrotics may be a feasible management strategy.

Cardiovascular safety of the tyrosine kinase inhibitor nintedanib

The intracellular tyrosine kinase inhibitor nintedanib has shown great efficacy for the treatment of idiopathic pulmonary fibrosis (IPF) and other interstitial lung diseases. However, the incidence rate of myocardial infarction (MI) among participants in landmark IPF trials was remarkable, peaking at 3/100 patient-years. Although subjects with IPF often have a high cardiovascular (CV) risk profile, the occurrence of MI in nintedanib-treated patients may not be fully explained by clustering of CV risk factors. Nintedanib inhibits the vascular endothelial growth factor, platelet-derived growth factor and fibroblast growth factor pathways, which play important roles in the biology of the atherosclerotic plaque and in the response of the heart to ischaemia. Hence, unwanted CV effects may partly account for nintedanib-related MI. We review the evidence supporting this hypothesis and discuss possible actions for a safe implementation of nintedanib in clinical practice, building on the experience with tyrosine kinase inhibitors acquired in cardio-oncology.

Baseline characteristics and survival of patients of idiopathic pulmonary fibrosis: a longitudinal analysis of the Swedish IPF Registry

Background

Observational data under real-life conditions in idiopathic pulmonary fibrosis (IPF) is scarce. We explored anti-fibrotic treatment, disease severity and phenotypes in patients with IPF from the Swedish IPF Registry (SIPFR).

Methods

Patients enrolled between September 2014 and April 2020 and followed ≥ 6 months were investigated. Demographics, comorbidities, lung function, composite variables, six-minute walking test (6MWT), quality of life, and anti-fibrotic therapy were evaluated. Agreements between classification of mild physiological impairment (defined as gender-age-physiology (GAP) stage 1) with physiological and composite measures of severity was assessed using kappa values and their impact on mortality with hazard ratios. The factor analysis and the two-step cluster analysis were used to identify phenotypes. Univariate and multivariable survival analyses were performed between variables or groups.

Results

Among 662 patients with baseline data (median age 72.7 years, 74.0% males), 480 had a follow up ≥ 6 months with a 5 year survival rate of 48%. Lung function, 6MWT, age, and BMI were predictors of survival. Patients who received anti-fibrotic treatment ≥ 6 months had better survival compared to untreated patients [p = 0.007, HR (95% CI): 1.797 (1.173–2.753)] after adjustment of age, gender, BMI, smoking status, forced vital capacity (FVC) and diffusion capacity of carbon monoxide (DLCO). Patients with mild physiological impairment (GAP stage 1, composite physiological index (CPI) ≤ 45, DLCO ≥ 55%, FVC ≥ 75%, and total lung capacity (TLC) ≥ 65%, respectively) had better survival, after adjustment for age, gender, BMI and smoking status and treatment. Patients in cluster 1 had the worst survival and consisted mainly of male patients with moderate-severe disease and an increased prevalence of heart diseases at baseline; Cluster 2 was characterized by mild disease with more than 50% females and few comorbidities, and had the best survival; Cluster 3 were younger, with moderate-severe disease and had few comorbidities.

Conclusion

Disease severity, phenotypes, and anti-fibrotic treatment are closely associated with the outcome in IPF, with treated patients surviving longer. Phenotypes may contribute to predicting outcomes of patients with IPF and suggest the patients’ need for special management, whereas single or composite variables have some limitations as disease predictors.

Drugs that act on the respiratory tract

No published data from this past year provide new insight on the safety and tolerability of corticosteroids, β2-adrenoreceptor agonists, or phosphodiesterase inhibitors as they pertain to respiratory diseases. While systemic corticosteroids have become a valuable therapeutic agent in treating Covid-19 pneumonia, there have been no new or unexpected adverse events reported within this context. Reports evaluating the psychiatric and vascular side effect profile of the leukotriene modifier, montelukast, are described below. For inhaled anticholinergic drugs, meta-analyses describe the cardiovascular safety of these agents, as well as the safety of tiotropium in pediatric patients. A case of mydriasis associated with ipratropium therapy is described. In addition, the safety of umeclidinium as part of a triple-drug inhaler was evaluated in a large randomized clinical trial. For the antifibrotic drugs nintedanib and pirfenidone, there are a number of reports describing the safety of these drugs in specific populations, and there are a number of case reports describing unique side effects. Lastly, there are new reports describing the safety of monoclonal antibody therapy for moderate to severe asthma, as well as a few case reports describing rare adverse events associated with benralizumab, dupilumab, mepolizumab, omalizumab, and reslizumab.