Progressive pulmonary fibrosis and its impact on survival in systemic sclerosis-related interstitial lung disease

Personalized Medicine for Systemic Sclerosis-Associated Interstitial Lung Disease

Purpose of the review

Systemic sclerosis (SSc) is a rare immune-mediated connective tissue disease with high morbidity and mortality. Interstitial lung disease (ILD) is now the leading cause of death for patients with SSc. While several therapeutic agents have been approved for SSc-ILD, opportunities remain for a personalized medicine approach to improve patient outcomes. The purpose of this narrative review is to summarize the current state of personalized medicine for SSc-ILD and future directions to facilitate earlier diagnosis, disease stratification, prognostication, and determination of treatment response. We also review opportunities for personalized medicine approaches within clinical trial design for SSc-ILD.

Recent findings

The management of SSc-ILD remains challenging due to its variable clinical course and current deficits in predicting which individuals will develop progressive pulmonary fibrosis. There have additionally been many challenges in clinical trial design due to limitations in enrichment strategies. Emerging data suggest that serum, radiologic, and other novel biomarkers could be utilized to assess disease activity and treatment response on an individual level.

Summary

Personalized medicine is emerging as a way to address unmet challenges in SSc-ILD and has applicability for identifying stratifying, prognostic, and therapeutic markers for routine clinical care and clinical trial design.

Sex Bias in Systemic Sclerosis: from Clinical to Immunological Differences

Systemic sclerosis (SSc) is a chronic autoimmune disease characterized by microvasculopathy, extensive fibrosis, and autoantibodies. The disease affects mostly the female sex. In this review, we highlight sex bias in clinical manifestations in SSc, and the pathophysiological changes underlying this bias. Male sex is associated with the diffuse cutaneous form of the disease, digital ulcers, interstitial lung disease, and worse prognosis. These clinical differences can be attributed to sex hormones and sex chromosomes, as females differ from males in sex hormones (estrogens in females, androgens in males) and sex chromosomes (XX in females, XY in males). Estrogens in females generally have immunostimulatory and profibrotic effects, and androgens have immunosuppressive effects. The X-chromosome contains many immunity-related genes, but the double dose of X-linked genes in females is avoided by random inactivation of one X-chromosome (XCI). However, many X-linked immunity-related genes, including toll-like receptor (TLR)7, TLR8 and Bruton's tyrosine kinase (BTK), escape XCI resulting in a biallelic expression with pathophysiological implications. Also, autosomal genes are differentially expressed between sexes. Therefore, sex should be included in future studies on SSc to aid in forming predictive algorithms and helping therapeutic decisions in this difficult-to-treat disease.

Radiological extent predicts prognosis and relapse after acute exacerbation of interstitial lung disease in patients with rheumatoid arthritis: KEIO-RA-cohort

To clarify how the extent of radiological interstitial lung abnormalities impacts the prognosis and risk of relapse in patients with rheumatoid arthritis (RA) following acute exacerbation of interstitial lung disease (AE-ILD). We conducted a retrospective review of all consecutive RA patients from the KEIO-RA cohort who experienced AE-ILD during 2012 to 2024. We investigated the association between the extent of abnormalities on high-resolution computed tomography (HRCT) images, as assessed by Goh's criteria, and outcomes in patients who survived AE-ILD versus those who did not, as well as between patients who survived AE-ILD without relapse and those who experienced relapse. Out of the 34 cases, 10 (29.4%) patients died due to AE-ILD. Of the 26 cases who survived the first AE-ILD event, 8 (30.8%) experienced a relapse, and 2 of them died. Non-survivors had higher Goh's HRCT scores both before and at the time of AE-ILD compared to survivors. Patients who experienced relapse had higher HRCT scores after AE-ILD compared to those who did not relapse. There were no significant differences in treatment regimens for AE-ILD, titers for anti-cyclic citrullinated peptide antibody or rheumatoid factor, or arthritis activity among the groups. Higher HRCT scores both before and at the time of AE-ILD are associated with increased mortality risk, while elevated scores after AE-ILD are linked to a higher likelihood of relapse. These findings highlight the critical role of HRCT assessment in guiding prognosis and post-AE-ILD management in patients with RA.

Characterization of Incident Interstitial Lung Disease in Late Systemic Sclerosis

OBJECTIVE

Interstitial lung disease (ILD) is a common and potentially lethal complication of systemic sclerosis (SSc). Screening by high-resolution computed tomography (HRCT) is recommended in all patients with risk factors, including early disease. Little is known on late presentations of ILD. This study aimed to characterize the incidence, risk factors, and outcomes of late-onset SSc-ILD.

METHODS

Study participants enrolled in the Canadian Scleroderma Research Group cohort from 2004 to 2020 without prevalent ILD were included. Incidence and risk factors for ILD (on HRCT) were compared according to disease duration above (late) and below (earlier) seven years from the first non-Raynaud manifestation. Risk of ILD progression was compared using Kaplan-Meier and multivariable Cox models.

RESULTS

Overall, 199 (21%) of 969 patients developed incident ILD over a median of 2.4 (interquartile range 1.2-4.3) years. The incidence rate in late SSc (3.7/100 person-years) was lower than in earlier SSc (relative risk 0.68, 95% confidence interval [CI] 0.51-0.92). Risk factors for incident ILD included male sex, diffuse subtype, myositis, antitopoisomerase I autoantibodies, and higher C-reactive protein levels. Patients with late-onset ILD were also less frequently White and more frequently had arthritis and anti-RNA-polymerase III autoantibodies. Lung disease severity was similar between late- and earlier-onset SSc-ILD (forced vital capacity 88% and 87%, diffusion capacity of the lungs for carbon monoxide 64% and 62%, respectively). Progression rates were also similar between late- and earlier-onset SSc-ILD (log rank P = 0.8, hazard ratio 1.11, 95% CI 0.58-2.10).

CONCLUSION

ILD can present in late SSc. Risk factors and progression rates overlapped with earlier-onset SSc-ILD. Surveillance for ILD should continue in longstanding SSc. Frequency and modality of monitoring remain to be defined.

Tocilizumab plus Nintedanib for progressive interstitial lung disease in systemic sclerosis: a one-year observational study

Randomized controlled trials have recently shown that both the IL-6 inhibitor Tocilizumab and the antifibrotic Nintedanib are efficacious for Systemic Sclerosis (SSc)-associated progressive interstitial lung disease (ILD). Since real-world clinical data on Tocilizumab/Nintedanib combination are lacking, we report on their long-term safety and efficacy. Consecutive patients who received off-label Tocilizumab for SSc plus Nintedanib for progressive ILD were retrospectively studied. Adverse events, and changes in Forced Vital Capacity (FVC), Diffucing Capacity for Carbon Monoxide (DLCO) and high resolution chest tomography (HRCT) between baseline and 6 and 12 months were assessed. Tocilizumab/Nintedanib combination was well tolerated by all 20 patients [aged 52 ± 13 years (mean ± SD), 14 women, 15 diffuse SSc, disease duration of 5.7 ± 4.9 years]; 7 of 20 patients received concomitant mycophenolate mofetil safely. No serious adverse events or laboratory abnormalities were noted. Five patients developed persistent diarrhea and 2 of them reduced dosage of Nintedanib. Baseline FVC (74%±12%) and DLCO (45%±10%) remained overall stable both at 6 months (73.5%±13% and 46%±11%, respectively) and 12 months (73%±14% and 45%±11%, respectively), regardless of disease duration. The extent of fibrotic reticular pattern in available pairs of HRCTs (n = 12) remained also stable at 12 months, whereas proportion (%) of ground glass opacities decreased from 29%±16 to 21%±14% (p = 0.048); improvement in HRCTs by almost 75% was noted in 2 of these12 patients. Tocilizumab/Nintedanib combination for one year was safe and stabilized lung function in real-world SSc patients with progressive ILD. Additional studies of this combination treatment in SSc-ILD are warranted.

Biomarkers in Systemic Sclerosis: An Overview

Systemic sclerosis (SSc) is a complex autoimmune disease characterized by significant fibrosis of the skin and internal organs, with the main involvement of the lungs, kidneys, heart, esophagus, and intestines. SSc is also characterized by macro- and microvascular damage with reduced peripheral blood perfusion. Several studies have reported more than 240 pathways and numerous dysregulation proteins, giving insight into how the field of biomarkers in SSc is still extremely complex and evolving. Antinuclear antibodies (ANA) are present in more than 90% of SSc patients, and anti-centromere and anti-topoisomerase I antibodies are considered classic biomarkers with precise clinical features. Recent studies have reported that trans-forming growth factor β (TGF-β) plays a central role in the fibrotic process. In addition, interferon regulatory factor 5 (IRF5), interleukin receptor-associated kinase-1 (IRAK-1), connective tissue growth factor (CTGF), transducer and activator of transcription signal 4 (STAT4), pyrin-containing domain 1 (NLRP1), as well as genetic factors, including DRB1 alleles, are implicated in SSc damage. Several interleukins (e.g., IL-1, IL-6, IL-10, IL-17, IL-22, and IL-35) and chemokines (e.g., CCL 2, 5, 23, and CXC 9, 10, 16) are elevated in SSc. While adiponectin and maresin 1 are reduced in patients with SSc, biomarkers are important in research but will be increasingly so in the diagnosis and therapeutic approach to SSc. This review aims to present and highlight the various biomarker molecules, pathways, and receptors involved in the pathology of SSc.