Nintedanib in the management of idiopathic pulmonary fibrosis: clinical trial evidence and real-world experience

The effect of TG2-inhibitory monoclonal antibody zampilimab on tissue fibrosis in human in vitro and primate in vivo models of chronic kidney disease

Fibrotic remodeling is the primary driver of functional loss in chronic kidney disease, with no specific anti-fibrotic agent available for clinical use. Transglutaminase 2 (TG2), a wound response enzyme that irreversibly crosslinks extracellular matrix proteins causing dysregulation of extracellular matrix turnover, is a well-characterized anti-fibrotic target in the kidney. We describe the humanization and characterization of two anti-TG2 monoclonal antibodies (zampilimab [hDC1/UCB7858] and BB7) that inhibit crosslinking by TG2 in human in vitro and rabbit/cynomolgus monkey in vivo models of chronic kidney disease. Determination of zampilimab half-maximal inhibitory concentration (IC50) against recombinant human TG2 was undertaken using the KxD assay and determination of dissociation constant (Kd) by surface plasmon resonance. Efficacy in vitro was established using a primary human renal epithelial cell model of tubulointerstitial fibrosis, to assess mature deposited extracellular matrix proteins. Proof of concept in vivo used a cynomolgus monkey unilateral ureteral obstruction model of chronic kidney disease. Zampilimab inhibited TG2 crosslinking transamidation activity with an IC50 of 0.25 nM and Kd of <50 pM. In cell culture, zampilimab inhibited extracellular TG2 activity (IC50 119 nM) and dramatically reduced transforming growth factor-β1-driven accumulation of multiple extracellular matrix proteins including collagens I, III, IV, V, and fibronectin. Intravenous administration of BB7 in rabbits resulted in a 68% reduction in fibrotic index at Day 25 post-unilateral ureteral obstruction. Weekly intravenous administration of zampilimab in cynomolgus monkeys with unilateral ureteral obstruction reduced fibrosis at 4 weeks by >50%, with no safety signals. Our data support the clinical investigation of zampilimab for the treatment of kidney fibrosis.

Reverse repurposing: Potential utility of cancer drugs in nonmalignant illnesses

Growth and immune process dysregulation can result in both cancer and nonmalignant disease (hereditary or acquired, with and without predisposition to malignancy). Moreover, perhaps unexpectedly, many nonmalignant illnesses harbor genomic alterations indistinguishable from druggable oncogenic drivers. Therefore, targeted compounds used successfully to treat cancer may have therapeutic potential for nonmalignant conditions harboring the same target. MEK, PI3K/AKT/mTOR, fibroblast growth factor receptor (FGFR), and NRG1/ERBB pathway genes have all been implicated in both cancer and noncancerous conditions, and several cognate antagonists, as well as Bruton's tyrosine kinase inhibitors, JAK inhibitors, and CD20-directed antibodies, have established or theoretical therapeutic potential to bridge cancer and benign diseases. Intriguingly, pharmacologically tractable cancer drivers characterize a wide spectrum of disorders without malignant potential, including but not limited to Alzheimer's disease and a variety of other neurodegenerative conditions, rheumatoid arthritis, achondroplastic dwarfism, and endometriosis. Expanded repositioning of oncology agents in order to benefit benign but serious medical illnesses is warranted.

Characterization of transient and progressive pulmonary fibrosis by spatially correlated phase contrast microCT, classical histopathology and atomic force microscopy

Pulmonary fibrosis (PF) is a severe and progressive condition in which the lung becomes scarred over time resulting in pulmonary function impairment. Classical histopathology remains an important tool for micro-structural tissue assessment in the diagnosis of PF. A novel workflow based on spatial correlated propagation-based phase-contrast micro computed tomography (PBI-microCT), atomic force microscopy (AFM) and histopathology was developed and applied to two different preclinical mouse models of PF - the commonly used and well characterized Bleomycin-induced PF and a novel mouse model for progressive PF caused by conditional Nedd4-2 KO. The aim was to integrate structural and mechanical features from hallmarks of fibrotic lung tissue remodeling. PBI-microCT was used to assess structural alteration in whole fixed and paraffin embedded lungs, allowing for identification of fibrotic foci within the 3D context of the entire organ and facilitating targeted microtome sectioning of planes of interest for subsequent histopathology. Subsequently, these sections of interest were subjected to AFM to assess changes in the local tissue stiffness of previously identified structures of interest. 3D whole organ analysis showed clear morphological differences in 3D tissue porosity between transient and progressive PF and control lungs. By integrating the results obtained from targeted AFM analysis, it was possible to discriminate between the Bleomycin model and the novel conditional Nedd4-2 KO model using agglomerative cluster analysis. As our workflow for 3D spatial correlation of PBI, targeted histopathology and subsequent AFM is tailored around the standard procedure of formalin-fixed paraffin-embedded (FFPE) tissue specimens, it may be a powerful tool for the comprehensive tissue assessment beyond the scope of PF and preclinical research.

Effect of antifibrotic agents on postoperative complications after lung transplantation for idiopathic pulmonary fibrosis

BACKGROUND

Antifibrotic agents (AFAs) are now standard-of-care for idiopathic pulmonary fibrosis (IPF). Concerns have arisen about the safety of these drugs in patients undergoing lung transplantation (LTx).

METHODS

We performed a multi-centre, nationwide, retrospective, observational study of French IPF patients undergoing LTx between 2011 and 2018 to determine whether maintaining AFAs in the peri-operative period leads to increased bronchial anastomoses issues, delay in skin healing and haemorrhagic complications. We compared the incidence of post-operative complications and the survival of patients according to AFA exposure.

RESULTS

Among 205 patients who underwent LTx for IPF during the study period, 58 (28%) had received AFAs within 4 weeks before LTx (AFA group): pirfenidone in 37 (18.0%) and nintedanib in 21 (10.2%). The median duration of AFA treatment before LTx was 13.8 (5.6-24) months. The AFA and control groups did not significantly differ in airway, bleeding or skin healing complications (p = 0.91, p = 0.12 and p = 0.70, respectively). Primary graft dysfunction was less frequent in the AFA than control group (26% vs. 43%, p = 0.02), and the 90-day mortality was lower (7% vs. 18%, p = 0.046).

CONCLUSIONS

AFA therapy did not increase airway, bleeding or wound post-operative complications after LTx and could be associated with reduced rates of primary graft dysfunction and 90-day mortality.

Crosstalk between fibroblasts and immunocytes in fibrosis: From molecular mechanisms to clinical trials

BACKGROUND

The impact of fibroblasts on the immune system provides insight into the function of fibroblasts. In various tissue microenvironments, multiple fibroblast subtypes interact with immunocytes by secreting growth factors, cytokines, and chemokines, leading to wound healing, fibrosis, and escape of cancer immune surveillance. However, the specific mechanisms involved in the fibroblast-immunocyte interaction network have not yet been fully elucidated.

MAIN BODY AND CONCLUSION

Therefore, we systematically reviewed the molecular mechanisms of fibroblast-immunocyte interactions in fibrosis, from the history of cellular evolution and cell subtype divisions to the regulatory networks between fibroblasts and immunocytes. We also discuss how these communications function in different tissue and organ statuses, as well as potential therapies targeting the reciprocal fibroblast-immunocyte interplay in fibrosis. A comprehensive understanding of these functional cells under pathophysiological conditions and the mechanisms by which they communicate may lead to the development of effective and specific therapies targeting fibrosis.

Superoxide dismutase secreting Bacillus amyloliquefaciens spores attenuate pulmonary fibrosis

Superoxide dismutase (SOD) can convert active oxygen to oxygen or hydrogen peroxide, and recent research has suggested that it can protect against lung damage and fibrosis. Clinical applications based on SOD remain limited however due to costs and low stability. We here investigated a potential new therapeutic delivery system for this enzyme in the form of SOD-overexpressing Bacillus amyloliquefaciens spores which we introduced into a bleomycin-induced pulmonary fibrosis mouse model. This treatment significantly alleviated the disease, as quantified using a hydroxyproline assay, at 107 colony forming unit (CFU) of Bacillus spores per day. Exposure of the mice to the spores was further found to decrease the lung mRNA levels of CTGF, Col1a1, α-SMA, TGF-β, TNF-α, and IL-6, and the protein levels of TGF-β, Smad2/3, αSMA and Col1a1, all major indicators of pulmonary fibrosis. Survival benefits, and reduced byproducts of lipid peroxidase such as malondialdehyde and 4-hydroxynen, were also noted in the treated animals. The beneficial effects of these Bacillus spores on pulmonary fibrosis were further found to be greater than the equivalent free SOD concentration. Immunofluorescence staining of primary pulmonary fibroblasts extracted from the bleomycin-induced model showed decreased αSMA expression following the in vivo treatment with SOD-overexpressing Bacillus. Our treatment approach SOD through Bacillus spores shows beneficial effects against pulmonary fibrosis, combined with the suppression of the SMAD/TGF-β pathway, suggesting that it is an effective novel delivery route for antioxidants.

Recent Advances in the Treatment of Interstitial Lung Diseases

Interstitial lung diseases (ILDs) are a group of disorders affecting the parenchymal tissue of the lungs. This disease leads to complications like pulmonary hypertension, heart failure, etc. that can affect patients. The etiological factors, clinical features, investigation methods, and diseases are conditions associated with ILD. The history of these conditions is of great value; any history of environmental and occupational exposure, medications, dust, or any toxic inhalation can be a predisposing factor. The CT scan is the investigation of choice in the case of ILD. This article states the recent advances made in treating interstitial lung diseases. The non-pharmacological and pharmacological management of ILD is discussed in the article. The discussion below concerns newer drugs approved by the FDA and their adverse effects, dosages, and contraindications. Below is a detailed conversation about ILD and the recent advances in treating this disease.

Long-circulating thiolated chitosan nanoparticles of nintedanib with N-acetyl cysteine for treating idiopathic pulmonary fibrosis: In vitro assessment of cytotoxicity, antioxidant, and antifibrotic potential

Nintedanib (NIN) is one of the FDA-approved tyrosine kinase inhibitor drugs used to treat idiopathic pulmonary fibrosis (IPF). This study aimed to formulate a long-circulating injection of Nintedanib to treat bedridden patients with IPF. Nintedanib was incorporated into chitosan nanoparticles (NIN-NP) via the ionic gelation method, and N-acetyl cysteine (NAC), a known antioxidant and mucolytic agent, was added to the NIN-NP (NAC-NIN-NP). The lyophilized formulation had a particle size of 174 nm, a polydispersity index of 0.511, and a zeta potential of 18.6 mV. The spherical nanoparticles were observed in transmission electron microscopy, whereas field emission scanning electron microscopy showed irregular clusters of NP. The thiolation of the chitosan in NAC-NIN-NP was confirmed by ATR-FTIR and NMR, which improved drug release profiles showing >90 % drug release that was 2.42-folds greater than NIN-NP lasting for five days. The DPPH assay showed that adding NAC increased the % inhibition of oxidation in blank-NP (from 54.59 % to 87.17 %) and NIN-NP (58.65 %-89.19 %). The MTT assay on A549 cells showed 67.57 % cell viability by NAC-NIN-NP with an IC50 value of 28 μg/mL. The NAC formulation reduced hydroxyproline content (56.77 μg/mL) compared to NIN-NP (69.48 μg/mL) in WI-38 cell lines. Meanwhile, the healthy cells count with NAC-NIN-NP was higher (5.104 × 103) than with NIN-NP (4.878 × 103). In Hoechst staining, no significant damage to DNA was observed by the drug or formulation. Therefore, NAC-NIN-NP could be a promising treatment option for IPF patients and can be studied further clinically.

The clinical impact of comorbidities among patients with idiopathic pulmonary fibrosis undergoing anti-fibrotic treatment: A multicenter retrospective observational study

BACKGROUND

Among patients with idiopathic pulmonary fibrosis (IPF), few studies have investigated the clinical impact of anti-fibrotic treatment (AFT) with and without comorbidities. The aim of the study was to determine whether Charlson Comorbidity Index score (CCIS) can predict the efficacy of AFT in patients with IPF.

METHODS

We retrospectively assessed data extracted from the medical records of IPF patients who received anti-fibrotic agents between 2009 and 2019. The collected data included age, sex, CCIS, pulmonary function test, high-resolution computed tomography (HRCT) pattern, gender/age/physiology (GAP) score, and 3-year IPF-related events defined as the first acute exacerbation or death within 3 years after starting AFT.

RESULTS

We assessed 130 patients (median age, 74 years) who received nintedanib (n = 70) or pirfenidone (n = 60). Median duration of AFT was 425 days. Patients were categorized into high (≥ 3 points) and low (≤ 2 points) CCIS groups. There was no significant difference between the groups in terms of age, sex, duration of AFT, GAP score, or incidence of usual interstitial pneumonia pattern on HRCT except percentage predicted diffusion capacity of lung for carbon monoxide. Also, significant difference was not seen between the groups for 3-year IPF-related events (P = 0.75). Especially, in the low CCIS group but not the high CCIS group, the longer duration of AFT had better disease outcome.

CONCLUSION

In the present study, we could not show any relation between CCIS and IPF disease outcomes in patients undergoing AFT, though the longer duration of AFT might be beneficial for IPF outcomes among patients with low CCIS.

The vascular perspective on acute and chronic lung disease

The pulmonary vasculature has been frequently overlooked in acute and chronic lung diseases, such as acute respiratory distress syndrome (ARDS), pulmonary fibrosis (PF), and chronic obstructive pulmonary disease (COPD). The primary emphasis in the management of these parenchymal disorders has largely revolved around the injury and aberrant repair of epithelial cells. However, there is increasing evidence that the vascular endothelium plays an active role in the development of acute and chronic lung diseases. The endothelial cell network in the capillary bed and the arterial and venous vessels provides a metabolically highly active barrier that controls the migration of immune cells, regulates vascular tone and permeability, and participates in the remodeling processes. Phenotypically and functionally altered endothelial cells, and remodeled vessels, can be found in acute and chronic lung diseases, although to different degrees, likely because of disease-specific mechanisms. Since vascular remodeling is associated with pulmonary hypertension, which worsens patient outcomes and survival, it is crucial to understand the underlying vascular alterations. In this Review, we describe the current knowledge regarding the role of the pulmonary vasculature in the development and progression of ARDS, PF, and COPD; we also outline future research directions with the hope of facilitating the development of mechanism-based therapies.

Exploring skeletal muscle tolerance and whole-body metabolic effects of FDA-approved drugs in a volumetric muscle loss model

Volumetric muscle loss (VML) is associated with persistent functional impairment due to a lack of de novo muscle regeneration. As mechanisms driving the lack of regeneration continue to be established, adjunctive pharmaceuticals to address the pathophysiology of the remaining muscle may offer partial remediation. Studies were designed to evaluate the tolerance and efficacy of two FDA-approved pharmaceutical modalities to address the pathophysiology of the remaining muscle tissue after VML injury: (1) nintedanib (an anti-fibrotic) and (2) combined formoterol and leucine (myogenic promoters). Tolerance was first established by testing low- and high-dosage effects on uninjured skeletal muscle mass and myofiber cross-sectional area in adult male C57BL/6J mice. Next, tolerated doses of the two pharmaceutical modalities were tested in VML-injured adult male C57BL/6J mice after an 8-week treatment period for their ability to modulate muscle strength and whole-body metabolism. The most salient findings indicate that formoterol plus leucine mitigated the loss in muscle mass, myofiber number, whole-body lipid oxidation, and muscle strength, and resulted in a higher whole-body metabolic rate (p ≤ 0.016); nintedanib did not exacerbate or correct aspects of the muscle pathophysiology after VML. This supports ongoing optimization efforts, including scale-up evaluations of formoterol treatment in large animal models of VML.

Discovery of indoline-based derivatives as effective ROCK2 inhibitors for the potential new treatment of idiopathic pulmonary fibrosis

Idiopathic pulmonary fibrosis (IPF) is a chronic, progressive, and devastating lung disease with a median survival of only 3-5 years. Due to the lack of effective therapy, IPF threatens human health. Recently, increasing reports have indicated that Rho-associated coiled-coil protein kinases (ROCKs) play important roles in the development of IPF and might represent a novel target for the treatment of IPF. Herein, a new series of selective ROCK2 inhibitors based on indoline were designed and synthesized. Structural modification resulted in optimized compound 9b with an IC₅₀ value of 6 nM against ROCK2 and the inhibition of collagen gel contraction. Cellular assays demonstrated that 9b could significantly suppress the expression of collagen I and α-SMA, and inhibited ROCK signaling pathway. Oral administration of compound 9b (10 mg/kg) exerted more significant anti-pulmonary fibrosis effects than nintedanib (100 mg/kg) and KD025 (100 mg/kg) in a bleomycin-induced IPF rat model, suggesting that 9b could serve as a potential lead compound for the treatment of IPF.

Vorapaxar proven to be a promising candidate for pulmonary fibrosis by intervening in the PAR1/JAK2/STAT1/3 signaling pathway-an experimental in vitro and vivo study

Idiopathic pulmonary fibrosis (IPF) is a lethal lung disease, and its 5-year mortality rate is even higher than the mortality rate of some cancers. Fibrosis can cause irreversible damage to lung structure and function. Treatment options for IPF remain limited, and there is an urgent need to develop effective therapeutic drugs. Protease activated receptor-1 (PAR-1) is a G-protein-coupled receptor and is considered a potential target for the treatment of fibrotic diseases. Vorapaxar is a clinically approved PAR-1 antagonist for cardiovascular protection. The purpose of this study was to explore the potential effect and mechanism of Vorapaxar on pulmonary fibrosis in vivo and in vitro. In the experimental animal model, Vorapaxar can effectively alleviate bleomycin (BLM)-induced pulmonary fibrosis. Treatment with 2.5, 5 or 10 mg/kg Vorapaxar once a day reduced the degree of fibrosis in a dose-dependent manner. The expression of fibronectin, collagen and α smooth muscle actin decreased significantly at the messenger RNA (mRNA) and protein levels in treated mice. In vitro, our results showed that Vorapaxar could inhibit the activation of fibroblasts induced by thrombin in a dose-dependent manner. In terms of mechanism, Vorapaxar inhibits the signal transduction of JAK2/STAT1/3 by inhibiting the activation of protease activated receptor 1, which reduces the expression of HSP90β and the interaction between HSP90β and transforming growth factor-β (TGFβ) receptor II and inhibits the TGFβ/Smad signaling pathway. In conclusion, Vorapaxar inhibits the activation of pulmonary fibroblasts induced by thrombin by targeting protease activated receptor 1 and alleviates BLM-induced pulmonary fibrosis in mice.

Assessing prognostic factors correlating with response to nintedanib for connective tissue disease-associated interstitial lung disease: A real-world single-center study

OBJECTIVE

For patients with connective tissue disease-associated interstitial lung disease (CTD-ILD), early medical intervention would be desirable. This study analyzed the real-world, single-center use of nintedanib for CTD-ILD patients.

METHODS

Patients with CTD who received nintedanib from January 2020 to July 2022 were enrolled. Medical records review and stratified analyses of the collected data were conducted.

RESULTS

Reduction in the percentage of predicted forced vital capacity (%FVC) was seen in the elderly group (>70 years; P = .210), males (P = .027), the late group who started nintedanib >80 months after confirmation of an ILD disease activity (P = .03), the severe %DLco (diffusing capacity for carbon monoxide as a percentage of predicted) group (<40%; P = .20), the group who had extensive pulmonary fibrosis at the beginning of nintedanib (pulmonary fibrosis score >35%), and the low-dose group (nintedanib 50-100 mg/d; P = .40). %FVC did not decrease by >5% in the young group (<55 years), the early group who started nintedanib within 10 months after confirmation of an ILD disease activity, and the group whose pulmonary fibrosis score at the beginning of nintedanib was <35%.

CONCLUSION

It is important to diagnose ILD early and start antifibrotic drugs with proper timing for cases in need. It is better to start nintedanib early, especially for patients at risk (>70 years old, male, <40% DLco, and >35% areas of pulmonary fibrosis).

The mechanical phenotypic plasticity of melanoma cell: an emerging driver of therapy cross-resistance

Advanced cutaneous melanoma is the deadliest form of skin cancer and one of the most aggressive human cancers. Targeted therapies (TT) against BRAF mutated melanoma and immune checkpoints blockade therapies (ICB) have been a breakthrough in the treatment of metastatic melanoma. However, therapy-driven resistance remains a major hurdle in the clinical management of the metastatic disease. Besides shaping the tumor microenvironment, current treatments impact transition states to promote melanoma cell phenotypic plasticity and intratumor heterogeneity, which compromise treatment efficacy and clinical outcomes. In this context, mesenchymal-like dedifferentiated melanoma cells exhibit a remarkable ability to autonomously assemble their own extracellular matrix (ECM) and to biomechanically adapt in response to therapeutic insults, thereby fueling tumor relapse. Here, we review recent studies that highlight mechanical phenotypic plasticity of melanoma cells as a hallmark of adaptive and non-genetic resistance to treatment and emerging driver in cross-resistance to TT and ICB. We also discuss how targeting BRAF-mutant dedifferentiated cells and ECM-based mechanotransduction pathways may overcome melanoma cross-resistance.

Macrophages as determinants and regulators of fibrosis in systemic sclerosis

SSc is a multiphase autoimmune disease with a well-known triad of clinical manifestations including vasculopathy, inflammation and fibrosis. Although a plethora of drugs has been suggested as potential candidates to halt SSc progression, nothing has proven clinically efficient. In SSc, both innate and adaptive immune systems are abnormally activated fuelling fibrosis of the skin and other vital organs. Macrophages have been implicated in the pathogenesis of SSc and are thought to be a major source of immune dysregulation. Due to their plasticity, macrophages can initiate and sustain chronic inflammation when classically activated while, simultaneously or parallelly, when alternatively activated they are also capable of secreting fibrotic factors. Here, we briefly explain the polarization process of macrophages. Subsequently, we link the activation of macrophages and monocytes to the molecular pathology of SSc, and illustrate the interplay between macrophages and fibroblasts. Finally, we present recent/near-future clinical trials and discuss novel targets related to macrophages/monocytes activation in SSc.

Multi-Targeting Approach in Selection of Potential Molecule for COVID-19 Treatment

The coronavirus disease (COVID-19) is a pandemic that started in the City of Wuhan, Hubei Province, China, caused by the spread of coronavirus (SARS-CoV-2). Drug discovery teams around the globe are in a race to develop a medicine for its management. It takes time for a novel molecule to enter the market, and the ideal way is to exploit the already approved drugs and repurpose them therapeutically. We have attempted to screen selected molecules with an affinity towards multiple protein targets in COVID-19 using the Schrödinger suit for in silico predictions. The proteins selected were angiotensin-converting enzyme-2 (ACE2), main protease (MPro), and spike protein. The molecular docking, prime MM-GBSA, induced-fit docking (IFD), and molecular dynamics (MD) simulations were used to identify the most suitable molecule that forms a stable interaction with the selected viral proteins. The ligand-binding stability for the proteins PDB-IDs 1ZV8 (spike protein), 5R82 (Mpro), and 6M1D (ACE2), was in the order of nintedanib > quercetin, nintedanib > darunavir, nintedanib > baricitinib, respectively. The MM-GBSA, IFD, and MD simulation studies imply that the drug nintedanib has the highest binding stability among the shortlisted. Nintedanib, primarily used for idiopathic pulmonary fibrosis, can be considered for repurposing for us against COVID-19.

Nintedanib induces senolytic effect via STAT3 inhibition

Selective removal of senescent cells, or senolytic therapy, has been proposed to be a potent strategy for overcoming age-related diseases and even for reversing aging. We found that nintedanib, a tyrosine kinase inhibitor, selectively induced the death of primary human dermal fibroblasts undergoing RS. Similar to ABT263, a well-known senolytic agent, nintedanib triggered intrinsic apoptosis in senescent cells. Additionally, at the concentration producing the senolytic effect, nintedanib arrested the cell cycle of nonsenescent cells in the G1 phase without inducing cytotoxicity. Interestingly, the mechanism by which nintedanib activated caspase-9 in the intrinsic apoptotic pathway differed from that of ABT263 apoptosis induction; specifically, nintedanib did not decrease the levels of Bcl-2 family proteins in senescent cells. Moreover, nintedanib suppressed the activation of the JAK2/STAT3 pathway, which caused the drug-induced death of senescent cells. STAT3 knockdown in senescent cells induced caspase activation. Moreover, nintedanib reduced the number of senescence-associated β-galactosidase-positive senescent cells in parallel with a reduction in STAT3 phosphorylation and ameliorated collagen deposition in a mouse model of bleomycin-induced lung fibrosis. Consistently, nintedanib exhibited a senolytic effect through bleomycin-induced senescence of human pulmonary fibroblasts. Overall, we found that nintedanib can be used as a new senolytic agent and that inhibiting STAT3 may be an approach for inducing the selective death of senescent cells. Our findings pave the way for expanding the senolytic toolkit for use in various aging statuses and age-related diseases.

[French practical guidelines for the diagnosis and management of IPF - 2021 update, full version]

BACKGROUND

Since the previous French guidelines were published in 2017, substantial additional knowledge about idiopathic pulmonary fibrosis has accumulated.

METHODS

Under the auspices of the French-speaking Learned Society of Pulmonology and at the initiative of the coordinating reference center, practical guidelines for treatment of rare pulmonary diseases have been established. They were elaborated by groups of writers, reviewers and coordinators with the help of the OrphaLung network, as well as pulmonologists with varying practice modalities, radiologists, pathologists, a general practitioner, a head nurse, and a patients' association. The method was developed according to rules entitled "Good clinical practice" in the overall framework of the "Guidelines for clinical practice" of the official French health authority (HAS), taking into account the results of an online vote using a Likert scale.

RESULTS

After analysis of the literature, 54 recommendations were formulated, improved, and validated by the working groups. The recommendations covered a wide-ranging aspects of the disease and its treatment: epidemiology, diagnostic modalities, quality criteria and interpretation of chest CT, indication and modalities of lung biopsy, etiologic workup, approach to familial disease entailing indications and modalities of genetic testing, evaluation of possible functional impairments and prognosis, indications for and use of antifibrotic therapy, lung transplantation, symptom management, comorbidities and complications, treatment of chronic respiratory failure, diagnosis and management of acute exacerbations of fibrosis.

CONCLUSION

These evidence-based guidelines are aimed at guiding the diagnosis and the management in clinical practice of idiopathic pulmonary fibrosis.

French practical guidelines for the diagnosis and management of idiopathic pulmonary fibrosis - 2021 update. Full-length version

BACKGROUND

Since the latest 2017 French guidelines, knowledge about idiopathic pulmonary fibrosis has evolved considerably.

METHODS

Practical guidelines were drafted on the initiative of the Coordinating Reference Center for Rare Pulmonary Diseases, led by the French Language Pulmonology Society (SPLF), by a coordinating group, a writing group, and a review group, with the involvement of the entire OrphaLung network, pulmonologists practicing in various settings, radiologists, pathologists, a general practitioner, a health manager, and a patient association. The method followed the "Clinical Practice Guidelines" process of the French National Authority for Health (HAS), including an online vote using a Likert scale.

RESULTS

After a literature review, 54 guidelines were formulated, improved, and then validated by the working groups. These guidelines addressed multiple aspects of the disease: epidemiology, diagnostic procedures, quality criteria and interpretation of chest CT scans, lung biopsy indication and procedures, etiological workup, methods and indications for family screening and genetic testing, assessment of the functional impairment and prognosis, indication and use of antifibrotic agents, lung transplantation, management of symptoms, comorbidities and complications, treatment of chronic respiratory failure, diagnosis and management of acute exacerbations of fibrosis.

CONCLUSION

These evidence-based guidelines are intended to guide the diagnosis and practical management of idiopathic pulmonary fibrosis.

Targeting fibrosis, mechanisms and cilinical trials

Fibrosis is characterized by the excessive extracellular matrix deposition due to dysregulated wound and connective tissue repair response. Multiple organs can develop fibrosis, including the liver, kidney, heart, and lung. Fibrosis such as liver cirrhosis, idiopathic pulmonary fibrosis, and cystic fibrosis caused substantial disease burden. Persistent abnormal activation of myofibroblasts mediated by various signals, such as transforming growth factor, platelet-derived growth factor, and fibroblast growh factor, has been recongized as a major event in the occurrence and progression of fibrosis. Although the mechanisms driving organ-specific fibrosis have not been fully elucidated, drugs targeting these identified aberrant signals have achieved potent anti-fibrotic efficacy in clinical trials. In this review, we briefly introduce the aetiology and epidemiology of several fibrosis diseases, including liver fibrosis, kidney fibrosis, cardiac fibrosis, and pulmonary fibrosis. Then, we summarise the abnormal cells (epithelial cells, endothelial cells, immune cells, and fibroblasts) and their interactions in fibrosis. In addition, we also focus on the aberrant signaling pathways and therapeutic targets that regulate myofibroblast activation, extracellular matrix cross-linking, metabolism, and inflammation in fibrosis. Finally, we discuss the anti-fibrotic drugs based on their targets and clinical trials. This review provides reference for further research on fibrosis mechanism, drug development, and clinical trials.

Clinical efficacy of Chinese herbs for supplementing qi and activating blood circulation combined with N-acetylcysteine in the treatment of idiopathic pulmonary fibrosis: A systematic review and network meta-analysis

BACKGROUND

Chinese herbs for supplementing qi and activating blood circulation (CH) combined with N-acetylcysteine (NAC) is widely used for idiopathic pulmonary fibrosis (IPF) in China, but there is a lack of literature to evaluate its efficacy and clinical value.

PURPOSE

This study compared CH + NAC with other treatments by network meta-analysis to clarify its clinical value.

METHODS

Cochrane Library, PubMed, Embase, Web of Science, China National Knowledge Infrastructure, WanFang Data, VIP Database, and China Biology Medicine were searched. Outcomes included lung function (DLCO (%), VC (%), FVC (%), FVC (L)), 6-min walking distance (6MWD), score of St George's respiratory questionnaire (SGRQ), blood gas analysis (PaO2, PaCO2). The data were analyzed by Review Manager 5.4, Stata 12.0 and ADDIS 1.16.5.

RESULTS

23 studies including 1390 patients (702 in intervention group and 688 in control group) were collected to compare 8 outcome indicators among different treatments involving CH, CH+NAC, CH+PFD, NAC, PFD and PFD+NAC on IPF. Network meta-analysis showed that CH was better than NAC in terms of DLCO (%) (MD = 5.14, 95%CI: 1.01 to 8.68) and 6MWD (MD = 49.17, 95%CI: 25.97 to 71.36) as well as PFD + NAC was better than NAC in terms of FVC (L) (MD = -0.56, 95%CI: -0.83 to -0.31). In rankings results, CH + NAC is the best in terms of FVC (%), SGRQ, PaO2 and PaCO2; CH is the best in terms of DLCO (%), VC (%) and 6MWD; CH + PFD is the best in terms of FVC (L).

CONCLUSION

CH related treatments may have advantages in the treatment of IPF and CH + NAC may have clinical application value. However, limited by the quality and quantity of researches included, more rational and scientific randomized controlled trials containing large sample sizes need to be conducted to further verify our conclusions.

Nintedanib and Dasatinib Treatments Induce Protective Autophagy as a Potential Resistance Mechanism in MPM Cells

Malignant pleural mesothelioma (MPM) is a rare type of cancer with a grim prognosis. So far, no targetable oncogenic mutation was identified in MPM and biomarkers with predictive value toward drug sensitivity or resistance are also lacking. Nintedanib (BIBF1120) is a small-molecule tyrosine kinase inhibitor that showed promising efficacy preclinically and in phase II trial in MPM as an angiogenesis inhibitor combined with chemotherapy. However, the extended phase III trial failed. In this study, we investigated the effect of nintedanib on one of its targets, the SRC kinase, in two commercial and six novel MPM cell lines. Surprisingly, nintedanib treatment did not inhibit SRC activation in MPM cells and even increased phosphorylation of SRC in several cell lines. Combination treatment with the SRC inhibitor dasatinib could reverse this effect in all cell lines, however, the cellular response was dependent on the drug sensitivity of the cells. In 2 cell lines, with high sensitivity to both nintedanib and dasatinib, the drug combination had no synergistic effect but cell death was initiated. In 2 cell lines insensitive to nintedanib combination treatment reduced cell viability synergisticaly without cell death. In contrast, in these cells both treatments increased the autophagic flux assessed by degradation of the autophagy substrate p62 and increased presence of LC3B-II, increased number of GFP-LC3 puncta and decreased readings of the HiBiT-LC3 reporter. Additionaly, autophagy was synergistically promoted by the combined treatment. At the transcriptional level, analysis of lysosomal biogenesis regulator Transcription Factor EB (TFEB) showed that in all cell lines treated with nintedanib and to a lesser extent, with dasatinib, it became dephosphorylated and accumulated in the nucleus. Interestingly, the expression of certain known TFEB target genes implicated in autophagy or lysosomal biogenesis were significantly modified only in 1 cell line. Finally, we showed that autophagy induction in our MPM cell lines panel by nintedanib and dasatinib is independent of the AKT/mTOR and the ERK pathways. Our study reveals that autophagy can serve as a cytoprotective mechanism following nintedanib or dasatinib treatments in MPM cells.

Impact of timing of nintedanib initiation among patients newly diagnosed with idiopathic pulmonary fibrosis

AIMS

While nintedanib treatment has been shown to slow the progression of idiopathic pulmonary fibrosis (IPF) in patients across varying levels of lung function, the effect of treatment timing on outcomes has not been examined. We assessed hospitalization risk and medical costs among patients with IPF based on the timing of nintedanib initiation after IPF diagnosis.

MATERIALS AND METHODS

This retrospective administrative claims study included data from 04/01/2014-09/30/2019 for patients aged ≥40 years who initiated nintedanib within 1 year of IPF diagnosis. Patients were assigned to study cohorts based on the time from IPF diagnosis to nintedanib initiation. All-cause hospitalization and all-cause medical costs were modeled using marginal structural models including inverse probability weights to adjust for both baseline and time-varying characteristics.

RESULTS

Of 11,195 patients diagnosed with IPF during the identification period, 449 met the study selection criteria (mean age 72.3 years, 68% male, mean follow-up time 13.3 months). Adjusted hospitalization risk and medical costs both varied significantly by the timing of nintedanib initiation (p < .001 and p = .020, respectively). Adjusted weighted hospitalization risk was higher among untreated vs. treated patients in months 2-3, months 4-6, and months 7-12 after diagnosis (hazard ratio [95% CI] 1.97 [1.09-3.56], p = .026; 2.62 [1.22-5.63], p = .014; and 5.57 [2.31-13.45], p < .001, respectively). Medical costs were 69% higher for patients initiating treatment in months 2-3 vs. month 1 (cost ratio [95% CI] 1.69 [1.20-2.38], p = .003).

LIMITATIONS

Disease severity could not be assessed because clinical data were unavailable; however, proxies such as oxygen use were included to adjust for between-cohort differences in disease severity.

CONCLUSIONS

Patients who initiate nintedanib promptly after IPF diagnosis may have reduced hospitalization risk and medical costs compared with those who start treatment later. Additional studies are warranted to improve understanding of the impact of prompt antifibrotic therapy on patient outcomes.

Fatty acid nitroalkene reversal of established lung fibrosis

Tissue fibrosis occurs in response to dysregulated metabolism, pro-inflammatory signaling and tissue repair reactions. For example, lungs exposed to environmental toxins, cancer therapies, chronic inflammation and other stimuli manifest a phenotypic shift to activated myofibroblasts and progressive and often irreversible lung tissue scarring. There are no therapies that stop or reverse fibrosis. The 2 FDA-approved anti-fibrotic drugs at best only slow the progression of fibrosis in humans. The present study was designed to test whether a small molecule electrophilic nitroalkene, nitro-oleic acid (NO₂-OA), could reverse established pulmonary fibrosis induced by the intratracheal administration of bleomycin in C57BL/6 mice. After 14 d of bleomycin-induced fibrosis development in vivo, lungs were removed, sectioned and precision-cut lung slices (PCLS) from control and bleomycin-treated mice were cultured ex vivo for 4 d with either vehicle or NO₂-OA (5 μM). Biochemical and morphological analyses showed that over a 4 d time frame, NO₂-OA significantly inhibited pro-inflammatory mediator and growth factor expression and reversed key indices of fibrosis (hydroxyproline, collagen 1A1 and 3A1, fibronectin-1). Quantitative image analysis of PCLS immunohistology reinforced these observations, revealing that NO₂-OA suppressed additional hallmarks of the fibrotic response, including alveolar epithelial cell loss, myofibroblast differentiation and proliferation, collagen and α-smooth muscle actin expression. NO₂-OA also accelerated collagen degradation by resident macrophages. These effects occurred in the absence of the recognized NO₂-OA modulation of circulating and migrating immune cell activation. Thus, small molecule nitroalkenes may be useful agents for reversing pathogenic fibrosis of lung and other organs.

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Small molecule electrophiles, pleiotropic anti-inflammatory and anti-fibrotic drugs.

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NO₂-OA inhibits activated myofibroblasts, induces dedifferentiation to fibroblasts.

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NO₂-OA activates extracellular matrix degradation by macrophages.

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NO₂-OA promotes proliferation of alveolar type 1 and 2 epithelial cells.

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NO₂-OA reverses established lung fibrosis in murine lung slices.

The tyrosine-kinase inhibitor Nintedanib ameliorates autosomal-dominant polycystic kidney disease

Autosomal-dominant polycystic kidney disease (ADPKD) is the most common inherited kidney disease and is characterized by progressive growth of fluid-filled cysts. Growth factors binding to receptor tyrosine kinases (RTKs) stimulate cell proliferation and cyst growth in PKD. Nintedanib, a triple RTK inhibitor, targets the vascular endothelial growth-factor receptor (VEGFR), platelet-derived growth-factor receptor (PDGFR), and fibroblast growth-factor receptor (FGFR), and is an approved drug for the treatment of non-small-cell lung carcinoma and idiopathic lung fibrosis. To determine if RTK inhibition using nintedanib can slow ADPKD progression, we tested its effect on human ADPKD renal cyst epithelial cells and myofibroblasts in vitro, and on Pkd1f/fPkhd1Cre and Pkd1RC/RC, orthologous mouse models of ADPKD. Nintedanib significantly inhibited cell proliferation and in vitro cyst growth of human ADPKD renal cyst epithelial cells, and cell viability and migration of human ADPKD renal myofibroblasts. Consistently, nintedanib treatment significantly reduced kidney-to-body-weight ratio, renal cystic index, cystic epithelial cell proliferation, and blood-urea nitrogen levels in both the Pkd1f/fPkhd1Cre and Pkd1RC/RC mice. There was a corresponding reduction in ERK, AKT, STAT3, and mTOR activity and expression of proproliferative factors, including Yes-associated protein (YAP), c-Myc, and Cyclin D1. Nintedanib treatment significantly reduced fibrosis in Pkd1RC/RC mice, but did not affect renal fibrosis in Pkd1f/fPkhd1Cre mice. Overall, these results suggest that nintedanib may be repurposed to effectively slow cyst growth in ADPKD.

Lung Fibrosis after COVID-19: Treatment Prospects

At the end of 2019, a highly contagious infection began its ominous conquest of the world. It was soon discovered that the disease was caused by a novel coronavirus designated as SARS-CoV-2, and the disease was thus abbreviated to COVID-19 (COVID). The global medical community has directed its efforts not only to find effective therapies against the deadly pathogen but also to combat the concomitant complications. Two of the most common respiratory manifestations of COVID are a significant reduction in the diffusing capacity of the lungs (DLCO) and the associated pulmonary interstitial damage. One year after moderate COVID, the incidence rate of impaired DLCO and persistent lung damage still exceeds 30%, and one-third of the patients have severe DLCO impairment and fibrotic lung damage. The persistent respiratory complications may cause substantial population morbidity, long-term disability, and even death due to the lung fibrosis progression. The incidence of COVID-induced pulmonary fibrosis caused by COVID can be estimated based on a 15-year observational study of lung pathology after SARS. Most SARS patients with fibrotic lung damage recovered within the first year and then remained healthy; however, in 20% of the cases, significant fibrosis progression was found in 5-10 years. Based on these data, the incidence rate of post-COVID lung fibrosis can be estimated at 2-6% after moderate illness. What is worse, there are reasons to believe that fibrosis may become one of the major long-term complications of COVID, even in asymptomatic individuals. Currently, despite the best efforts of the global medical community, there are no treatments for COVID-induced pulmonary fibrosis. In this review, we analyze the latest data from ongoing clinical trials aimed at treating post-COVID lung fibrosis and analyze the rationale for the current drug candidates. We discuss the use of antifibrotic therapy for idiopathic pulmonary fibrosis, the IN01 vaccine, glucocorticosteroids as well as the stromal vascular fraction for the treatment and rehabilitation of patients with COVID-associated pulmonary damage.

Baseline plasma KL-6 level predicts adverse outcomes in patients with idiopathic pulmonary fibrosis receiving nintedanib: a retrospective real-world cohort study

Background

Nintedanib is effective for treating idiopathic pulmonary fibrosis (IPF), but some patients may exhibit a suboptimal response and develop on-treatment acute exacerbation (AE-IPF), hepatic injury, or mortality. It remains unclear which patients are at risk for these adverse outcomes.

Methods

We analysed the demographic and clinical data, baseline plasma levels of Krebs von den Lungen-6 (KL-6) and surfactant protein A (SPA), and longitudinal clinical courses of a real-world cohort of IPF patients who received nintedanib ≥ 14 days between March 2017 and December 2020. Cox proportional-hazards regression, subdistribution hazards regression, and sensitivity analyses were performed to investigate the association between baseline predictors and AE-IPF, mortality, and nintedanib-related hepatic injury. The relationship between baseline predictors and pulmonary function decline was determined.

Results

Fifty-seven patients were included, of whom 24 (42%) developed hepatic injury, 20 (35%) had AE-IPF, and 16 (28%) died on-treatment. A baseline plasma KL-6 level ≥ 2.5 ng/mL, and diffusion capacity for carbon monoxide (D_LCO) < 55% predicted, were associated with increased risk of hepatic injury (adjusted hazard ratio [aHR] was 3.46; 95% CI 1.13–10.60; p = 0.029 for KL-6, and 6.05; 95% CI 1.89–19.32; p = 0.002 for D_LCO). Both factors also predicted severe and recurrent hepatic injury. Patients with baseline KL-6 ≥ 2.5 ng/mL also had a higher risk of AE-IPF (aHR 4.52; 95% CI 1.63–12.55; p = 0.004). For on-treatment mortality, baseline KL-6 ≥ 3.5 ng/mL and SPA ≥ 600 pg/mL were significant predictors (aHR 5.39; 95% CI 1.16–24.97; p = 0.031 for KL-6, and aHR 12.28; 95% CI 2.06–73.05; p = 0.006 for SPA). Results from subdistribution hazard regression and sensitivity analyses supported these findings. Patients with elevated baseline plasma KL-6 levels also exhibited a trend towards faster pulmonary function decline.

Conclusions

For patients with IPF who are receiving nintedanib, we have identified baseline predictors, in particular plasma KL-6 levels, for the risk of adverse outcomes. Patients with these predictors may require close monitoring for unfavourable responses during treatment. Our findings also support the prognostic role of molecular markers like KL-6 and may contribute to future formulation of more individualized therapeutic strategies for IPF.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12890-021-01530-6.

Aortic intramural haematoma associated with the use of nintedanib

We report a 74-year-old patient who developed an acute aortic syndrome (AAS) with intramural haematoma (IMH) during treatment with nintedanib, a tyrosine kinase inhibitor. As we suspected a role for nintedanib, this was immediately interrupted. Four months later, a computed tomographic angiography (CTA) showed significant regression of the IMH. Therefore, we state that, when patients use nintedanib and develop acute chest or back pain, diagnostic work-up for AAS should be considered. Furthermore, other risk factors for AAS, such as hypertension, genetic diseases and comedication should be taken into account when prescription of medication of this class is considered.

Delphi Consensus Recommendations on Management of Dosing, Adverse Events, and Comorbidities in the Treatment of Idiopathic Pulmonary Fibrosis with Nintedanib

Purpose:

Nintedanib is an approved treatment for idiopathic pulmonary fibrosis (IPF), which slows disease progression. Management of patients with IPF receiving nintedanib can be complicated by tolerability issues, comorbidities, and concomitant medications. We developed consensus recommendations on the management of dosing, adverse events and comorbidities in patients with IPF treated with nintedanib.

Methods:

A modified Delphi process using 3 questionnaires was used to survey 14 pulmonologists experienced in using nintedanib. Panelists rated their agreement with statements on a Likert scale from −5 (strongly disagree) to +5 (strongly agree). Consensus was predefined as a mean score of ⩽−2.5 or ⩾+2.5 with a standard deviation not crossing zero.

Results:

The panelists’ recommendations were largely aligned with clinical trial data, real-world evidence, and the prescribing information, and provided additional guidance regarding minimizing gastrointestinal effects, periodic monitoring for liver dysfunction, caution with respect to concomitant administration of cytochrome P450 3A4 and P-glycoprotein 1 inhibitors and inducers and anticoagulants, and management of comorbidities. The panelists unanimously agreed that adverse event management should be individualized, based on careful consideration of the risks and benefits of each possible intervention and discussion with the patient.

Conclusions:

These consensus recommendations provide additional guidance on the appropriate management of IPF with nintedanib, for use alongside evidence-based literature and the prescribing information.

Efficacy and Tolerability of Nintedanib in Idiopathic-Inflammatory-Myopathy-Related Interstitial Lung Disease: A Pilot Study

Objectives: To initially clarify the efficacy and tolerability of nintedanib in patients with idiopathic-inflammatory-myopathy-related interstitial lung disease (IIM-ILD).

Methods: A retrospective, real-world analysis was conducted in IIM-ILD patients who regularly received outpatient visit or hospitalization from January 2018 to March 2020 in three centers. And the patients were divided into two groups depending on presence or absence of nintedanib therapy. Comparisons, Kaplan-Meier survival analysis and propensity score matching were made to identify difference in time to death from any cause, incidence of rapidly progressive interstitial lung disease (RP-ILD) and comorbidity of pulmonary infection between the two groups. The following logistic regression analyses and Cox proportional-hazard regression analyses were used to verify the therapeutic value of nintedanib as well as clinical significance of other factors. Adverse events were descriptively recorded.

Results: Thirty-six patients receiving nintedanib therapy and 115 patients without use of nintedanib were included. Before and after propensity score matching, the primary comparisons revealed better survival (P = 0.015, P = 0016, respectively) and lower incidence of RP-ILD (P = 0.017, P = 0.014, respectively) in patients with nintedanib therapy. Logistic regression analysis identified that disease activity (P < 0.001), percent-predicted diffusing capacity of the lung for carbon monoxide (DLCO%, P = 0.036), nintedanib therapy (P = 0.004, OR value = 0.072) and amyopathic dermatomyositis (ADM, P = 0.012) were significantly correlated with RP-ILD. Cox proportional hazards regression analysis suggested that disease activity (P < 0.001), anti-MDA5 antibody (P < 0.001) and nintedanib therapy (P = 0.013, HR value=0.268) were significantly associated with survival of IIM-ILD patients. Similar results can also be seen in analyses after propensity score matching. In the 36 patients with nintedanib therapy, diarrhea was the most common adverse event (44.4%) and hepatic insufficiency contributed to most dosage reduction (44.4% of nine patients) or therapy discontinuation (60.0% of five patients).

Conclusions: Nintedanib was found to reduce incidence of RP-ILD and improve survival in IIM-ILD patients in a real-world setting. Anti-MDA5 antibody could be taken as a risk factor for unfavorable outcome. ADM was significantly correlated with occurrence of RP-ILD. In addition to the most frequent diarrhea, hepatic insufficiency was closely related to dosage reduction or therapy discontinuation.

Proteomics in idiopathic pulmonary fibrosis: the quest for biomarkers

Idiopathic pulmonary fibrosis (IPF) is a debilitating chronic progressive and fibrosing lung disease that culminates in the destruction of alveolar integrity and dismal prognosis. Its etiology is unknown and pathophysiology remains unclear. While great advances have been made in elucidating the pathogenesis mechanism, considerable gaps related to information on pathogenetic pathways and key protein targets involved in the clinical course of the disease exist. These issues need to be addressed for better clinical management of this highly challenging disease. Omics approach has revolutionized the entire area of disease understanding and holds promise in its translation to clinical biomarker discovery. This review outlines the contribution of proteomics towards identification of important biomarkers in IPF in terms of their clinical utility, i.e. prognosis, differential diagnosis, disease progression and treatment monitoring. The major dysregulated pathways associated with IPF are also discussed. Based on numerous proteomics studies on human and animal models, it is proposed that IPF pathogenesis involves complex interactions of several pathways such as oxidative stress, endoplasmic reticulum stress, unfolded protein response, coagulation system, inflammation, abnormal wounding, fibroblast proliferation, fibrogenesis and deposition of extracellular matrix. These pathways and their key path-changing mediators need further validation in large well-planned multi-centric trials at various geographical locations for successful development of clinical biomarkers of this confounding disease.

Identification of Pro-Fibrotic Macrophage Populations by Single-Cell Transcriptomic Analysis in West Highland White Terriers Affected With Canine Idiopathic Pulmonary Fibrosis

Canine idiopathic pulmonary fibrosis (CIPF) affects old dogs from the West Highland white terrier (WHWT) breed and mimics idiopathic pulmonary fibrosis (IPF) in human. The disease results from deposition of fibrotic tissue in the lung parenchyma causing respiratory failure. Recent studies in IPF using single-cell RNA sequencing (scRNA-seq) revealed the presence of profibrotic macrophage populations in the lung, which could be targeted for therapeutic purpose. In dogs, scRNA-seq was recently validated for the detection of cell populations in bronchoalveolar lavage fluid (BALF) from healthy dogs. Here we used the scRNA-seq to characterize disease-related heterogeneity within cell populations of macrophages/monocytes (Ma/Mo) in the BALF from five WHWTs affected with CIPF in comparison with three healthy WHWTs. Gene set enrichment analysis was also used to assess pro-fibrotic capacities of Ma/Mo populations. Five clusters of Ma/Mo were identified. Gene set enrichment analyses revealed the presence of pro-fibrotic monocytes in higher proportion in CIPF WHWTs than in healthy WHWTs. In addition, monocyte-derived macrophages enriched in pro-fibrotic genes in CIPF compared with healthy WHWTs were also identified. These results suggest the implication of Ma/Mo clusters in CIPF processes, although, further research is needed to understand their role in disease pathogenesis. Overexpressed molecules associated with pulmonary fibrosis processes were also identified that could be used as biomarkers and/or therapeutic targets in the future.

Why is a paediatric respiratory specialist integral to the paediatric rheumatology clinic?

Systemic connective tissue diseases (CTDs) are characterised by the presence of autoantibodies and multiorgan involvement. Although CTDs are rare in children, they are associated with pulmonary complications, which have a high morbidity and mortality rate. The exact pathophysiology remains unclear. The pleuropulmonary complications in CTD are diverse in their manifestations and are often complex to diagnose and manage. The most common CTDs are discussed. These include juvenile systemic lupus erythematosus, juvenile dermatomyositis, juvenile systemic sclerosis, Sjögren's syndrome and mixed connective tissue disease. We describe the clinical features of the pleuropulmonary complications, focusing on their screening, diagnosis and monitoring. Treatment strategies are also discussed, highlighting the factors and interventions that influence the outcome of lung disease in CTD and pulmonary complications of treatment. Early detection and prompt treatment in a multidisciplinary team setting, including respiratory and rheumatology paediatricians and radiologists, is paramount in achieving the best possible outcomes for these patients.

Classifying the Linkage between Adipose Tissue Inflammation and Tumor Growth through Cancer-Associated Adipocytes

Recently, tumor microenvironment (TME) and its stromal constituents have provided profound insights into understanding alterations in tumor behavior. After each identification regarding the unique roles of TME compartments, non-malignant stromal cells are found to provide a sufficient tumorigenic niche for cancer cells. Of these TME constituents, adipocytes represent a dynamic population mediating endocrine effects to facilitate the crosstalk between cancer cells and distant organs, as well as the interplay with nearby tumor cells. To date, the prevalence of obesity has emphasized the significance of metabolic homeostasis along with adipose tissue (AT) inflammation, cancer incidence, and multiple pathological disorders. In this review, we summarized distinct characteristics of hypertrophic adipocytes and cancer to highlight the importance of an individual's metabolic health during cancer therapy. As AT undergoes inflammatory alterations inducing tissue remodeling, immune cell infiltration, and vascularization, these features directly influence the TME by favoring tumor progression. A comparison between inflammatory AT and progressing cancer could potentially provide crucial insights into delineating the complex communication network between uncontrolled hyperplastic tumors and their microenvironmental components. In turn, the comparison will unravel the underlying properties of dynamic tumor behavior, advocating possible therapeutic targets within TME constituents.

COVID-19: The Potential Treatment of Pulmonary Fibrosis Associated with SARS-CoV-2 Infection

In December 2019, a novel coronavirus, SARS-CoV-2, appeared, causing a wide range of symptoms, mainly respiratory infection. In March 2020, the World Health Organization (WHO) declared Coronavirus Disease 2019 (COVID-19) a pandemic, therefore the efforts of scientists around the world are focused on finding the right treatment and vaccine for the novel disease. COVID-19 has spread rapidly over several months, affecting patients across all age groups and geographic areas. The disease has a diverse course; patients may range from asymptomatic to those with respiratory failure, complicated by acute respiratory distress syndrome (ARDS). One possible complication of pulmonary involvement in COVID-19 is pulmonary fibrosis, which leads to chronic breathing difficulties, long-term disability and affects patients' quality of life. There are no specific mechanisms that lead to this phenomenon in COVID-19, but some information arises from previous severe acute respiratory syndrome (SARS) or Middle East respiratory syndrome (MERS) epidemics. The aim of this narrative review is to present the possible causes and pathophysiology of pulmonary fibrosis associated with COVID-19 based on the mechanisms of the immune response, to suggest possible ways of prevention and treatment.

Eupatilin treatment inhibits transforming growth factor beta-induced endometrial fibrosis in vitro

Objective

Endometrial fibrosis, the primary pathological feature of intrauterine adhesion, may lead to disruption of endometrial tissue structure, menstrual abnormalities, infertility, and recurrent pregnancy loss. At present, no ideal therapeutic strategy exists for this fibrotic disease. Eupatilin, a major pharmacologically active flavone from Artemisia, has been previously reported to act as a potent inducer of dedifferentiation of fibrotic tissue in the liver and lung. However, the effects of eupatilin on endometrial fibrosis have not yet been investigated. In this study, we present the first report on the impact of eupatilin treatment on transforming growth factor beta (TGF-β)-induced endometrial fibrosis.

Methods

The efficacy of eupatilin on TGF-β–induced endometrial fibrosis was assessed by examining changes in morphology and the expression levels of fibrosis markers using immunofluorescence staining and quantitative real-time reverse-transcription polymerase chain reaction.

Results

Eupatilin treatment significantly reduced the fibrotic activity of TGF-β–induced endometrial fibrosis in Ishikawa cells, which displayed more circular shapes and formed more colonies. Additionally, the effects of eupatilin on fibrotic markers including alpha-smooth muscle actin, hypoxia-inducible factor 1 alpha, collagen type I alpha 1 chain, and matrix metalloproteinase-2, were evaluated in TGF-β–induced endometrial fibrosis. The expression of these markers was highly upregulated by TGF-β pretreatment and recovered to the levels of control cells in response to eupatilin treatment.

Conclusion

Our findings suggest that suppression of TGF-β–induced signaling by eupatilin might be an effective therapeutic strategy for the treatment of endometrial fibrosis.

Bad Neighborhood: Fibrotic Stroma as a New Player in Melanoma Resistance to Targeted Therapies

Current treatments for metastatic cutaneous melanoma include immunotherapies and drugs targeting key molecules of the mitogen-activated protein kinase (MAPK) pathway, which is often activated by BRAF driver mutations. Overall responses from patients with metastatic BRAF mutant melanoma are better with therapies combining BRAF and mitogen-activated protein kinase kinase (MEK) inhibitors. However, most patients that initially respond to therapies develop drug resistance within months. Acquired resistance to targeted therapies can be due to additional genetic alterations in melanoma cells and to non-genetic events frequently associated with transcriptional reprogramming and a dedifferentiated cell state. In this second scenario, it is possible to identify pro-fibrotic responses induced by targeted therapies that contribute to the alteration of the melanoma tumor microenvironment. A close interrelationship between chronic fibrosis and cancer has been established for several malignancies including breast and pancreatic cancers. In this context, the contribution of fibrosis to drug adaptation and therapy resistance in melanoma is rapidly emerging. In this review, we summarize recent evidence underlining the hallmarks of fibrotic diseases in drug-exposed and resistant melanoma, including increased remodeling of the extracellular matrix, enhanced actin cytoskeleton plasticity, high sensitivity to mechanical cues, and the establishment of an inflammatory microenvironment. We also discuss several potential therapeutic options for manipulating this fibrotic-like response to combat drug-resistant and invasive melanoma.

Lung transplantation: a review of the optimal strategies for referral and patient selection

One of the great challenges of lung transplantation is to bridge the dichotomy between supply and demand of donor organs so that the maximum number of potential recipients achieve a meaningful benefit in improvements in survival and quality of life. To achieve this laudable goal is predicated on choosing candidates who are sufficiently unwell, in fact possessing a terminal respiratory illness, but otherwise fit and able to undergo major surgery and a prolonged recuperation and rehabilitation stage combined with ongoing adherence to complex medical therapies. The choice of potential candidate and the timing of that referral is at times perhaps more art than science, but there are a number of solid guidelines for specific illnesses to assist the interested clinician. In this regard, the relationship between the referring clinician and the lung transplant unit is a critical one. It is an ongoing and dynamic process of education and two way communication, which is a marker of the professionalism of a highly performing unit. Lung transplantation is ultimately a team effort where the recipient is the key player. That principle has been enshrined in the three consensus position statements regarding selection criteria for lung and heart-lung transplantation promulgated by the International Society for Heart and Lung Transplantation over the last two decades. During this period, the number of indications for lung transplantation have broadened and the number of contraindications reduced. Risk management is paramount in the pre- and perioperative period to effect early successful outcomes. While it is not the province of this review to reiterate the detailed listing of those factors, an overview position will be developed that describes the rationale and evidence for selected criteria where that exists. Importantly, the authors will attempt to provide an historical and experiential basis for making these important and life-determining decisions.

The reviews of this paper are available via the supplementary material section.

Morphomolecular motifs of pulmonary neoangiogenesis in interstitial lung diseases

The pathogenetic role of angiogenesis in interstitial lung diseases (ILDs) is controversial. This study represents the first investigation of the spatial complexity and molecular motifs of microvascular architecture in important subsets of human ILD. The aim of our study was to identify specific variants of neoangiogenesis in three common pulmonary injury patterns in human ILD.We performed comprehensive and compartment-specific analysis of 24 human lung explants with usual intersitial pneumonia (UIP), nonspecific interstitial pneumonia (NSIP) and alveolar fibroelastosis (AFE) using histopathology, microvascular corrosion casting, micro-comupted tomography based volumetry and gene expression analysis using Nanostring as well as immunohistochemistry to assess remodelling-associated angiogenesis.Morphometrical assessment of vessel diameters and intervascular distances showed significant differences in neoangiogenesis in characteristically remodelled areas of UIP, NSIP and AFE lungs. Likewise, gene expression analysis revealed distinct and specific angiogenic profiles in UIP, NSIP and AFE lungs.Whereas UIP lungs showed a higher density of upstream vascularity and lower density in perifocal blood vessels, NSIP and AFE lungs revealed densely packed alveolar septal blood vessels. Vascular remodelling in NSIP and AFE is characterised by a prominent intussusceptive neoangiogenesis, in contrast to UIP, in which sprouting of new vessels into the fibrotic areas is characteristic. The molecular analyses of the gene expression provide a foundation for understanding these fundamental differences between AFE and UIP and give insight into the cellular functions involved.

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

BACKGROUND

The efficacy and effectiveness of nintedanib as a first-line therapy in idiopathic pulmonary fibrosis (IPF) patients have been demonstrated by clinical trials and real-life studies. Our aim was to examine the safety profile and effectiveness of nintedanib when it is utilized as a second-line treatment in subjects who have discontinued pirfenidone.

METHODS

The medical charts of 12 patients who were switched from pirfenidone to nintedanib were examined retrospectively. The drug's safety was defined by the number of adverse events (AEs) that were reported; disease progression was evaluated based on the patient's vital status and changes in forced vital capacity (FVC) at 12-month follow-up.

RESULTS

The numbers of patients experiencing AEs and of the AEs per patient in our study group didn't significantly differ with respect to a group of 56 individuals who were taking nintedanib as a first-line therapy during the study period (5/12 vs. 22/56; p = 0.9999, and 0.00 (0.00-1.00) vs. 0.00 (0.00-3.00); p = 0.517, respectively). Two out of the 3 patients who had been switched to nintedanib due to a rapid disease progression showed stabilized FVC values.

CONCLUSIONS

Nintedanib was found to have an acceptable safety profile in the majority of the IPF patients switched from pirfenidone. Prospective studies are warranted to determine if the drug can effectively delay disease progression in these patients.

Efficacy and safety of nintedanib in a Greek multicentre idiopathic pulmonary fibrosis registry: a retrospective, observational, cohort study

Nintedanib is a tyrosine kinase inhibitor approved for the treatment of idiopathic pulmonary fibrosis (IPF). In a retrospective, real-world study across seven Greek hospitals, we evaluated the effectiveness and safety of nintedanib in routine clinical practice. Patients diagnosed with IPF, as per guideline criteria or multidisciplinary diagnosis, received nintedanib between January 2013 and January 2018.

We evaluated 244 patients: mean±sd age 71.8±7.5 years, 79.1% male, 45.1% current smokers and 33.1% ex-smokers at treatment initiation. At baseline, predicted forced vital capacity (FVC) was 73.3±20.7% and predicted diffusing capacity of the lungs for carbon monoxide (D_LCO) was 42.6±16.7%. On average, patients spent 23.6±15.0 months on nintedanib. At 3 years, 78 patients had died, equating to a 3-year survival rate of 59.4% (unaffected by treatment discontinuation or dose reduction). FVC% pred and D_LCO% pred were largely stable at 3 years, with no significant difference from baseline (FVC 73.3±20.7% pred versus 78±20.1% pred, p=0.074; D_LCO 42.6±16.7% pred versus 40.4±18.1% pred, p=0.334). Of the 244 patients, 55.7% reported an adverse event. Gastrointestinal events were the most common (173 (77.2%) out of 224 total events) and 45.0% of patients experienced diarrhoea. Only 32 (13.1%) patients had to permanently discontinue nintedanib due to an adverse event.

This real-world study shows a 3-year survival rate of 59.4% and a low discontinuation rate due to adverse events. Our experience is consistent with previous findings in clinical trials of nintedanib in IPF.

Findings from the largest registry of Greek patients with IPF receiving nintedanib in routine clinical practice show, over a 3-year period, a low discontinuation rate and efficacy data that support the results of the INPULSIS clinical trialshttp://bit.ly/35a2CS5

Ongoing challenges in pulmonary fibrosis and insights from the nintedanib clinical programme

The approvals of nintedanib and pirfenidone changed the treatment paradigm in idiopathic pulmonary fibrosis (IPF), and increased our understanding of the underlying disease mechanisms. Nonetheless, many challenges and unmet needs remain in the management of patients with IPF and other progressive fibrosing interstitial lung diseases.This review describes how the nintedanib clinical programme has helped to address some of these challenges. Data from this programme have informed changes to the IPF diagnostic guidelines, the timing of treatment initiation, and the assessment of disease progression. The use of nintedanib to treat patients with advanced lung function impairment, concomitant emphysema, patients awaiting lung transplantation and patients with IPF and lung cancer is discussed. The long-term use of nintedanib and an up-to-date summary of nintedanib in clinical practice are discussed. Directions for future research, namely emerging therapeutic options, precision medicine and other progressive fibrosing interstitial lung diseases, are described.Further developments in these areas should continue to improve patient outcomes.

Chronic respiratory diseases: An introduction and need for novel drug delivery approaches

Globally, chronic respiratory diseases (CRDs), both communicable and noncommunicable, are among the leading causes of mortality, morbidity, economic and societal burden, and disability-adjusted life years (DALYs). CRDs affect multiple components of respiratory system, including the airways, parenchyma, and pulmonary vasculature. Although noncommunicable respiratory diseases, such as asthma, chronic obstructive pulmonary disease (COPD), interstitial lung disease (ILD), cystic fibrosis (CF), and lung cancer (LC), account for enormous disease burden, the currently available therapies only focus on alleviating the symptoms of diseases rather than providing optimal treatment and/or prevention. Similarly a major respiratory communicable disease, that is, tuberculosis (TB), is associated with the challenge of increasingly developing antibiotic resistance in the bacterial pathogen Mycobacterium tuberculosis. In light of these challenges, we aim to summarize the underlying molecular and cellular mechanisms that lead to hallmark pathophysiology of CRDs. Moreover, we will also highlight the limitations of current therapeutic strategies and explore novel drug delivery options that may be potentially more effective in the management of CRDs.

New therapeutic strategies for IPF: Based on the "phagocytosis-secretion-immunization" network regulation mechanism of pulmonary macrophages

Pulmonary fibrosis is a chronic and progressive interstitial lung disease of known and unknown etiology. Over the past decades, macrophages have been recognized to play a significant role in IPF pathogenesis. According to their anatomical loci, macrophages can be divided to alveolar macrophages (AMs) subtypes and interstitial macrophages subtypes (IMs) with different responsibility in the damage defense response. Depending on diverse chemokines and cytokines in local microenvironments, macrophages can be induced and polarized to either classically activated (M1) or alternatively activated (M2) phenotypes in different stages of immunity. Therefore, we hypothesize that there is a "phagocytosis-secretion-immunization" network regulation of pulmonary macrophages related to a number of chemokines and cytokines. In this paper, we summarize and discuss the role of chemokines and cytokines involved in the "phagocytosis-secretion-immunization" network regulation mechanism of pulmonary macrophages, pointing toward novel therapeutic approaches based on the network target regulation in the field. Therapeutic strategies focused on modifying the chemokines, cytokines and the network are promising for the pharmacotherapy of IPF. Some Traditional Chinese medicines may have more superiorities in delaying the progression of pulmonary fibrosis for their multi-target activities of this network regulation.