Long-Term Safety of Antifibrotic Drugs in IPF: A Real-World Experience

Bexotegrast Shows Dose-Dependent Integrin αvβ6 Receptor Occupancy in Lungs of Participants with Idiopathic Pulmonary Fibrosis: A Phase 2, Open-Label Clinical Trial

Rationale: Idiopathic pulmonary fibrosis (IPF) is a chronic and progressive disease characterized by dyspnea and loss of lung function. Transforming growth factor-β (TGF-β) activation mediated by αv integrins is central to the pathogenesis of IPF. Bexotegrast (PLN-74809) is an oral, once-daily, dual-selective inhibitor of αvβ6 and αvβ1 integrins under investigation for the treatment of IPF. Positron emission tomography (PET) using an αvβ6-specific PET tracer could confirm target engagement of bexotegrast in the lungs of participants with IPF. Objectives: This Phase 2 study evaluated αvβ6 receptor occupancy in the lung as assessed by changes from baseline in αvβ6 PET tracer uptake, after single-dose administration of bexotegrast to participants with IPF. Methods: In this open-label, single-center study, adults with IPF received up to two single doses of bexotegrast, ranging from 60 to 320 mg with or without background IPF therapy (pirfenidone or nintedanib). At baseline and approximately 4 hours after each orally administered bexotegrast dose, a 60-minute dynamic PET-computed tomography scan was conducted after administration of an αvβ6-specific PET probe ([18F]FP-R01-MG-F2). αvβ6 receptor occupancy by bexotegrast was estimated from the changes in PET tracer uptake after bexotegrast administration. Pharmacokinetics, safety, and tolerability of bexotegrast were also assessed. Results: Eight participants completed the study. Total and unbound plasma bexotegrast concentrations increased in a dose-dependent manner, and regional PET volume of distribution values decreased in a dose- and concentration-dependent manner. The data for volume of distribution fit a simple saturation model, producing an unbound bexotegrast half maximal effective concentration estimate of 3.32 ng/ml. Estimated maximum receptor occupancy was 35%, 53%, 71%, 88%, and 92% after single 60-, 80-, 120-, 240-, and 320-mg doses of bexotegrast, respectively. No treatment-emergent adverse events related to bexotegrast were reported. Conclusions: Dose and concentration-dependent αvβ6 receptor occupancy by bexotegrast was observed by PET imaging, supporting once-daily 160- to 320-mg dosing to evaluate efficacy in clinical trials of IPF. Clinical trial registered with www.clinicaltrials.gov (NCT04072315).

Pharmacological Treatment of Interstitial Lung Diseases: A Novel Landscape for Inhaled Agents

Interstitial lung diseases (ILDs) encompass a heterogeneous group of over 200 disorders that require individualized treatment. Antifibrotic agents, such as nintedanib and pirfenidone, have remarkably revolutionized the treatment landscape of patients with idiopathic pulmonary fibrosis (IPF). Moreover, the approval of nintedanib has also expanded the therapeutic options for patients with progressive pulmonary fibrosis other than IPF. However, despite recent advances, current therapeutic strategies based on antifibrotic agents and/or immunomodulation are associated with non-negligible side effects. Therefore, several studies have explored the inhalation route aiming to spread higher local concentrations while limiting systemic toxicity. In this review, we examined the currently available literature about preclinical and clinical studies testing the efficacy and safety of inhalation-based antifibrotics, immunomodulatory agents, antioxidants, mucolytics, bronchodilators, and vasodilator agents in ILDs.

Real-world safety and effectiveness of pirfenidone and nintedanib in the treatment of idiopathic pulmonary fibrosis: a systematic review and meta-analysis

BACKGROUND AND OBJECTIVE

Multiple randomized controlled studies have shown that pirfenidone and nintedanib are effective and safe for treating idiopathic pulmonary fibrosis. This study aimed to evaluate their efficacy, safety, and tolerability in a real-world setting.

METHODS

We searched PubMed, Embase, Cochrane Library, and ClinicalTrials.gov databases for real-world studies published up to March 3, 2023, on pirfenidone and nintedanib for idiopathic pulmonary fibrosis.

RESULTS

A total of 74 studies with 23,119 participants were included. After 12 months of treatment, the change from baseline in percent predicted FVC (%FVC) was - 0.75% for pirfenidone and - 1.43% for nintedanib. The change from baseline in percent predicted DLCO (%DCLO) was - 2.32% for pirfenidone and - 3.95% for nintedanib. The incidence of acute exacerbation of idiopathic pulmonary fibrosis (AE-IPF) was 12.5% for pirfenidone and 14.4% for nintedanib. The IPF-related mortality rates of pirfenidone and nintedanib were 13.4% and 7.2%, respectively. The all-cause mortality was 20.1% for pirfenidone and 16.6% for nintedanib. In the pirfenidone group, 16.6% of patients discontinued treatment because of adverse events, and in the nintedanib group, 16.2% of patients discontinued treatment because of adverse events. The incidence of adverse events was 56.4% and 69.7% for pirfenidone and nintedanib, respectively.

CONCLUSION

The results of this study indicate that pirfenidone and nintedanib are both effective in slowing down the decline of lung function in IPF patients in real-world settings. The incidence of adverse events with pirfenidone is lower than that with nintedanib, but both are below the clinical trial data, and no new major adverse events have been observed. The discontinuation rates due to adverse reactions of the two drugs are consistent with clinical trial data, indicating good tolerability. However, the mortality rates and AE-IPF incidence rates of these two drugs in real-world settings are higher than those in previous clinical trials, with pirfenidone patients showing a higher mortality rate. Further large-sample studies are needed to investigate the risks of these drugs in these aspects. Additionally, we recommend that future real-world studies pay more attention to patients' subjective symptoms and conduct stratified analyses of the efficacy and safety of pirfenidone and nintedanib based on factors such as patients' baseline lung function, comorbidities, and age, in order to provide more personalized medication advice for IPF patients in clinical practice.

Use of pirfenidone in fibrotic interstitial lung diseases and beyond: a review

The pathophysiological mechanisms involved in fibrotic interstitial lung diseases (FILDs) are akin to those observed in idiopathic pulmonary fibrosis (IPF), implying the potential for shared therapeutic approaches. Pirfenidone exhibits antifibrotic and anti-inflammatory properties, making it the first small-molecule drug approved for treating IPF. Pirfenidone has been utilized in IPF treatment for more than one decade. However, guidelines for progressive pulmonary fibrosis (PPF) treatment suggest that further research and evidence are needed to fully comprehend its efficacy and safety across various PPF subtypes. In recent years, numerous studies have explored the use of pirfenidone in treating non-IPF FILD. Herein, we provide an overview of the latest research data on application of pirfenidone in occupational-related ILD, connective tissue disease-associated ILD, post-coronavirus disease-2019 pulmonary fibrosis, and other conditions. We summarize the level of evidence and highlight challenges associated with using pirfenidone in different FILDs to offer clinical guidance.

Pirfenidone and Nintedanib in Pulmonary Fibrosis: Lights and Shadows

Pirfenidone and Nintedanib are specific drugs used against idiopathic pulmonary fibrosis (IPF) that showed efficacy in non-IPF fibrosing interstitial lung diseases (ILD). Both drugs have side effects that affect patients in different ways and have different levels of severity, making treatment even more challenging for patients and clinicians. The present review aims to assess the effectiveness and potential complications of Pirfenidone and Nintedanib treatment regimens across various ILD diseases. A detailed search was performed in relevant articles published between 2018 and 2023 listed in PubMed, UpToDate, Google Scholar, and ResearchGate, supplemented with manual research. The following keywords were searched in the databases in all possible combinations: Nintedanib; Pirfenidone, interstitial lung disease, and idiopathic pulmonary fibrosis. The most widely accepted method for evaluating the progression of ILD is through the decline in forced vital capacity (FVC), as determined by respiratory function tests. Specifically, a decrease in FVC over a 6-12-month period correlates directly with increased mortality rates. Antifibrotic drugs Pirfenidone and Nintedanib have been extensively validated; however, some patients reported several side effects, predominantly gastrointestinal symptoms (such as diarrhea, dyspepsia, and vomiting), as well as photosensitivity and skin rashes, particularly associated with Pirfenidone. In cases where the side effects are extremely severe and are more threatening than the disease itself, the treatment has to be discontinued. However, further research is needed to optimize the use of antifibrotic agents in patients with PF-ILDs, which could slow disease progression and decrease all-cause mortality. Finally, other studies are requested to establish the treatments that can stop ILD progression.

Antifibrotic treatment adherence, efficacy and outcomes for patients with idiopathic pulmonary fibrosis in Spain: a real-world evidence study

BACKGROUND

Idiopathic pulmonary fibrosis (IPF) is a rare disorder associated with increased mortality and morbidity. There are currently two drugs approved for IPF but their safety and efficacy profile in real-world settings in Spain is not well understood.

METHODS

An observational, multicentre, prospective study was carried out among patients with IPF who started treatment with pirfenidone or nintedanib from 2015 to 2021. Data regarding clinical characteristics, drug adherence, safety profiles and clinical outcomes between these two drugs were collected.

RESULTS

232 patients were included in the analysis. There were no meaningful differences between both groups at baseline. Patients who started pirfenidone showed a decreased risk for treatment withdrawal compared with those starting nintedanib (HR 0.65 (95% CI 0.46 to 0.94; p=0.002)). Time to first adverse event and all-cause mortality was similar between study groups. Risk factors for withdrawal were female sex, diarrhoea and photosensitivity.

CONCLUSIONS

in this real-world study, both pirfenidone and nintedanib showed similar efficacy profiles. Pirfenidone was associated with less treatment discontinuations due to side effects.

Clinical course of mild-to-moderate idiopathic pulmonary fibrosis during therapy with pirfenidone: Results of the non-interventional study AERplus

INTRODUCTION

Pirfenidone was the first anti-fibrotic drug approved in Europe in 2011 for the treatment of mild-to-moderate idiopathic pulmonary fibrosis.

OBJECTIVES

To investigate the clinical course of mild-to-moderate idiopathic pulmonary fibrosis in pirfenidone-treated patients in a real-world setting.

METHODS

The non-interventional study was conducted at 18 sites in Germany from 6/2014-12/2016. Adult patients with mild-to-moderate idiopathic pulmonary fibrosis were treated with pirfenidone (escalated from 3×1 to 3×3 capsules of 267 mg/day within 3 weeks) for 12 months. The observation period comprised 4 follow-up visits at months 3, 6, 9 and 12. Disease progression was defined as decrease of ≥10% in vital capacity or ≥15% in diffusing capacity of the lung for carbon monoxide (DLCO) and/or ≥50m in 6-minute walking distance vs. baseline, or "lack of response/progression" as reason for therapy discontinuation.

RESULTS

A total of 51 patients (80.4% male, mean age 70.6 years) were included in the full analysis set. Disease progression at any visit was reported for 23 (67.6%) of 34 patients with available data. Over the course of the study, lung function parameters, physical resilience, impact of cough severity on quality of life, and the mean Gender, Age and Physiology Index (stage II) remained stable. In total, 29 patients (56.9%) experienced at least one adverse drug reaction (11 patients discontinued due to adverse drug reactions); serious adverse reactions were reported in 12 patients (23.5%).

CONCLUSIONS

The results of this study are in line with the established benefit-risk profile of pirfenidone. Therefore, pirfenidone can be considered a valuable treatment option to slow disease progression in mild-to-moderate idiopathic pulmonary fibrosis. NCT02622477.

TrxR/Trx inhibitor butaselen ameliorates pulmonary fibrosis by suppressing NF-κB/TGF-β1/Smads signaling

Pulmonary fibrosis is highly lethal with limited treatments. Butaselen (BS) is an inhibitor of thioredoxin reductase (TrxR)/thioredoxin (Trx) with anti-tumor activity. However, its impact on pulmonary fibrosis and the involved mechanisms remain unclear. Here, we demonstrate that BS is a potential drug for the treatment of pulmonary fibrosis. Specifically, BS can inhibit pulmonary fibrosis both in vitro and in vivo, with comparable efficacy and enhanced safety when compared with pirfenidone. BS and dexamethasone display a synergistic effect in inhibiting pulmonary fibrosis both in vitro and in vivo. Mechanistic studies reveal that BS can inhibit the TrxR activity during pulmonary fibrosis. RNA-sequencing analysis identifies that genes of ECM-related signaling pathways are notably affected by BS. BS can not only inhibit the activation of nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) and reduce pulmonary fibrosis-related inflammation, but also reduce NF-κB-activated transcriptional expression of transforming growth factor-β1 (TGF-β1), which leads to the inactivation of Smad2/Smad3 and decrease of collagen formation and fibrosis. Moreover, the knockdown of Trx1 with siRNA can also inhibit NF-κB/TGF-β1/Smads signaling. In conclusion, the TrxR/Trx inhibitor butaselen can suppress pulmonary fibrosis by inhibiting NF-κB/TGF-β1/Smads signaling.

A Real-World Multicenter Retrospective Observational Study on Polish Experience with Nintedanib Therapy in Patients with Idiopathic Pulmonary Fibrosis: The PolExNIB Study

Nintedanib is a disease-modifying agent licensed for the treatment of IPF. Data on Polish experience with nintedanib in IPF are lacking. The present study aimed to describe the safety and efficacy profiles of nintedanib in a large real-world cohort of Polish patients with IPF. This was a multicenter, retrospective, observational study of IPF patients treated with nintedanib between March 2018 and October 2021. Data collection included baseline clinical characteristics, results of pulmonary function tests (PFTs), and a six-minute walk test (6MWT). Longitudinal data on PFTs, 6MWT, adverse drug reactions (ADRs), and treatment persistence were also retrieved. A total of 501 patients (70% male) with a median age of 70.9 years (IQR 65-75.7) were included in this study. Patients were followed on treatment for a median of 15 months (7-25.5). The majority of patients (66.7%) were treated with the full recommended dose of nintedanib and 33.3% of patients were treated with a reduced dose of a drug. Intermittent dose reductions or drug interruptions were needed in 20% of patients. Over up to 3 years of follow-up, pulmonary function remained largely stable with the minority experiencing disease progression. The most frequent ADRs included diarrhea (45.3%), decreased appetite (29.9%), abdominal discomfort (29.5%), weight loss (32.1%), nausea (20.8%), fatigue (19.2%), increased liver aminotransferases (15.4%), and vomiting (8.2%). A total of 203 patients (40.5%) discontinued nintedanib treatment due to diverse reasons including ADRs (10.2%), death (11.6%), disease progression (4.6%), patient's request (6.6%), and neoplastic disease (2.2%). This real-world study of a large cohort of Polish patients with IPF demonstrates that nintedanib therapy is safe, and is associated with acceptable tolerance and disease stabilization. These data support the findings of previously conducted clinical trials and observational studies on the safety and efficacy profiles of nintedanib in IPF.

Mannosylated polydopamine nanoparticles alleviate radiation- induced pulmonary fibrosis by targeting M2 macrophages and inhibiting the TGF-β1/Smad3 signaling pathway

Radiation-induced pulmonary fibrosis (RIPF), one type of pulmonary interstitial diseases, is frequently observed following radiation therapy for chest cancer or accidental radiation exposure. Current treatments against RIPF frequently fail to target lung effectively and the inhalation therapy is hard to penetrate airway mucus. Therefore, this study synthesized mannosylated polydopamine nanoparticles (MPDA NPs) through one-pot method to treat RIPF. Mannose was devised to target M2 macrophages in the lung through CD 206 receptor. MPDA NPs showed higher efficiency of penetrating mucus, cellular uptake and ROS-scavenging than original polydopamine nanoparticles (PDA NPs) in vitro. In RIPF mice, aerosol administration of MPDA NPs significantly alleviated the inflammatory, collagen deposition and fibrosis. The western blot analysis demonstrated that MPDA NPs inhibited TGF-β1/Smad3 signaling pathway against pulmonary fibrosis. Taken together this study provide a novel M2 macrophages-targeting nanodrugs through aerosol delivery for the prevention and targeted treatment for RIPF.