Recent advances steer the future of systemic sclerosis toward precision medicine

The role of skin ultrasound in systemic sclerosis: looking below the surface to understand disease evolution

Skin ultrasound has shown promising results in the evaluation of skin involvement in patients with systemic sclerosis, as substantiated by a recent systematic literature review from the World Scleroderma Foundation Skin Ultrasound Working Group. In this Viewpoint, we will discuss the role of ultrasound in evaluating skin involvement in patients with systemic sclerosis, particularly the possibility of using this technique to detect an early subclinical skin involvement from the very early phase, suggesting its possible use in both diagnosis and disease follow-up. To detect subclinical skin involvement, it is essential to understand the difference between the skin of patients with systemic sclerosis and that of healthy controls, including defining exactly which structures are affected by the disease and which are spared. The potential of this non-invasive technique might suggest its future role in both clinical practice and clinical trials, possibly replacing invasive and painful procedures such as skin biopsies and promoting patient retention in clinical trials.

Insights into molecular and clinical characteristics of very early systemic sclerosis

PURPOSE OF REVIEW

The early heterogenous presentation of systemic sclerosis (SSc), in particular without skin involvement, has been a confounding factor delaying early diagnosis. In fact, early signs of SSc as Raynaud's phenomenon and puffy fingers, are also typical of other connective tissue diseases (CTDs) such as mixed CTD and undifferentiated CTD. In the last decade, a significant effort has been dedicated in defining molecular characteristics that could be used as early SSc biomarkers. In this narrative review, we address the present situation where several clinical scenarios are in search of a correct positioning into the prescleroderma (pre-SSc) phase as well as in the very early phase of SSc.

RECENT FINDINGS

Literature data showed that a part of patients classified as sine scleroderma SSc (ssSSc), mixed CTD and undifferentiated CTD may already belong to the very early phase of SSc, thus having a different pattern of progression to SSc. Recently, the very early diagnosis of systemic sclerosis (VEDOSS) criteria has been validated.

SUMMARY

while the area of pre-SSc still remains fuzzy, the VEDOSS study has shown that a 'window of opportunity' does exist also for SSc. In the very next future, this may allow to start the treatment to prevent the disease progression to a more advanced fibrotic stage.

The Use and Utility of Machine Learning in Achieving Precision Medicine in Systemic Sclerosis: A Narrative Review

Background: Systemic sclerosis (SSc) is a rare connective tissue disease that can affect different organs and has extremely heterogenous presentations. This complexity makes it difficult to perform an early diagnosis and a subsequent subclassification of the disease. This hinders a personalized approach in clinical practice. In this context, machine learning (ML), a branch of artificial intelligence (AI), is able to recognize relationships in data and predict outcomes. Methods: Here, we performed a narrative review concerning the application of ML in SSc to define the state of art and evaluate its role in a precision medicine context. Results: Currently, ML has been used to stratify SSc patients and identify those at high risk of severe complications. Additionally, ML may be useful in the early detection of organ involvement. Furthermore, ML might have a role in target therapy approach and in predicting drug response. Conclusion: Available evidence about the utility of ML in SSc is sparse but promising. Future improvements in this field could result in a big step toward precision medicine. Further research is needed to define ML application in clinical practice.

Primary systemic sclerosis heart involvement: A systematic literature review and preliminary data-driven, consensus-based WSF/HFA definition

Introduction

Primary heart involvement in systemic sclerosis may cause morpho-functional and electrical cardiac abnormalities and is a common cause of death. The absence of a clear definition of primary heart involvement in systemic sclerosis limits our understanding and ability to focus on clinical research. We aimed to create an expert consensus definition for primary heart involvement in systemic sclerosis.

Methods

A systematic literature review of cardiac involvement and manifestations in systemic sclerosis was conducted to inform an international and multi-disciplinary task force. In addition, the nominal group technique was used to derive a definition that was then subject to voting. A total of 16 clinical cases were evaluated to test face validity, feasibility, reliability and criterion validity of the newly created definition.

Results

In total, 171 publications met eligibility criteria. Using the nominal group technique, experts added their opinion, provided statements to consider and ranked them to create the consensus definition, which received 100% agreement on face validity. A median 60(5-300) seconds was taken for the feasibility on a single case. Inter-rater agreement was moderate (mKappa (95% CI) = 0.56 (0.46-1.00) for the first round and 0.55 (0.44-1.00) for the second round) and intra-rater agreement was good (mKappa (95% CI) = 0.77 (0.47-1.00)). Criterion validity showed a 78 (73-84)% correctness versus gold standard.

Conclusion

A preliminary primary heart involvement in systemic sclerosis consensus-based definition was created and partially validated, for use in future clinical research.

Therapeutic Options for Systemic Sclerosis: Current and Future Perspectives in Tackling Immune-Mediated Fibrosis

Systemic sclerosis (SSc) is a severe auto-immune, rheumatic disease, characterized by excessive fibrosis of the skin and visceral organs. SSc is accompanied by high morbidity and mortality rates, and unfortunately, few disease-modifying therapies are currently available. Inflammation, vasculopathy, and fibrosis are the key hallmarks of SSc pathology. In this narrative review, we examine the relationship between inflammation and fibrosis and provide an overview of the efficacy of current and novel treatment options in diminishing SSc-related fibrosis based on selected clinical trials. To do this, we first discuss inflammatory pathways of both the innate and acquired immune systems that are associated with SSc pathophysiology. Secondly, we review evidence supporting the use of first-line therapies in SSc patients. In addition, T cell-, B cell-, and cytokine-specific treatments that have been utilized in SSc are explored. Finally, the potential effectiveness of tyrosine kinase inhibitors and other novel therapeutic approaches in reducing fibrosis is highlighted.

Physical activity in idiopathic inflammatory myopathies: two intervention proposals based on literature review

Idiopathic inflammatory myopathies (IIM) are rare diseases affecting skeletal muscles and leading to progressive muscle weakness and disability. Thanks to the better understanding of their pathogenesis, the management of IIM has been noteworthily implemented in recent years. Current therapeutic strategies include pharmacological and non-pharmacological interventions, among which physical exercise represents a useful option, able to ameliorate disease activity without worsening muscle inflammation. The aim of this narrative review is therefore to provide an updated overview of the benefits of physical exercise in patients with IIM and to suggest plausible training programs to be applied in patients with dermatomyositis, polymyositis, necrotizing myopathy, and inclusion body myositis. In this regard, a combined strategy mixing aerobic and resistance exercises could positively affect the pro-inflammatory and metabolic pathways occurring in skeletal muscles, while promoting muscle fiber regeneration and repair.

Prediction and primary prevention of major vascular complications in systemic sclerosis

OBJECTIVE

In Systemic Sclerosis (SSc), vasculopathy is the background of major vascular complications (MVCs), like digital ulcers (DUs), pulmonary arterial hypertension (PAH) and scleroderma renal crisis (SRC). We aimed to identify the predictors and to test the primary preventive effect of vasoactive/vasodilating drugs (VVD) for the development of MVCs in SSc MVCs-naïve patients.

METHODS

patients fulfilling the ACR/EULAR 2013 classification criteria for SSc without history of MVCs were eligible. Data about clinical manifestations, laboratory and instrumental assessments and treatments were retrospectively collected at baseline and latest available follow-up.

RESULTS

134 SSc patients were enrolled (mean age 56.5 years ± 14.2, females 88.1%, limited subset 61.9%, ACA positivity 60.4%). In a mean of 43 ± 19 months of follow-up 12 (9.0%) patients developed at least 1 MVC (10 DU, 2 PAH and 1 SRC). Dyspnoea and arthritis at baseline were independent predictors for MVCs development (p = 0.012, and p = 0.002 respectively). No primary preventive effect of VVD on MVCs development was found. However, sildenafil reduced the renal resistive index increase (p = 0.042) and alprostadil slowed the DLco decline (p = 0.029). Both iloprost and angiotensin-receptor blockers (ARBs) delayed MVCs development, while angiotensin converting enzyme inhibitors (ACEi) determined an earlier onset of such MCVs.

CONCLUSIONS

in SSc patients, our data confirm the role of arthritis and dyspnea as independent predictors of major vascular complications, in particular in MVCs-naïve patients. Prostanoids, sildenafil and ARBs, even in absence of a primary preventive action, might help in slowing disease progression and postponing the onset of MVCs.

Cardiac involvement in systemic sclerosis: Getting to the heart of the matter

Primary systemic sclerosis heart involvement (pSHI) is an important disease manifestation that accounts for a significant proportion of systemic sclerosis (SSc)-associated mortality. A broad clinical spectrum of pSHI exists, which ranges from asymptomatic perfusion abnormalities to diastolic dysfunction or acute myocarditis and congestive heart failure. With improving sensitivity of cardiac investigations, it is increasingly recognized that there is a large burden of subclinical cardiac disease in patients with SSc. Early signs of pSHI can be subtle and determining the etiology of cardiac abnormalities from other causes of cardiomyopathy such as hypertension, ischemic heart disease (IHD), and pulmonary vascular disease remain challenging. Early identification of pSHI potentially provides clinicians with a window of opportunity for intervention to avert progression to heart failure. However, optimal screening and treatment guidelines are lacking, and it is an area of much needed further clinical research.

The Treatment of Lung Involvement in Systemic Sclerosis

Systemic sclerosis (SSc) patients are often affected by interstitial lung disease (ILD) and, although there have been recent treatment advances, it remains the leading cause of death among SSc, with a 10-year mortality up to 40%. African Americans and subjects with diffuse cutaneous SSc or anti-topoisomerase 1 antibodies are most commonly affected. Currently, early ILD diagnosis can be made, and it is pivotal to improve the prognosis. The diagnostic mainstay test for SSc-ILD is high-resolution computed tomography for the morphology and pulmonary function tests for the functional aspects. Treatment planning and intensity are guided by the disease severity and risk of progression. Traditionally, therapy has depended on combinations of immunosuppressants, particularly cyclophosphamide and mycophenolate mofetil, which can be supplemented by targeted biological and antifibrotic therapies. Benefits have been observed in trials on hematopoietic autologous stem cell transplantation for patients with progressive SSc, whilst lung transplantation is reserved for refractory SSc-ILD cases. Herein, recent advances in SSc-ILD treatment will be explored.

Considerations for a combined index for limited cutaneous systemic sclerosis to support drug development and improve outcomes

Systemic sclerosis (SSc; systemic scleroderma) is characterized by a heterogeneous range of clinical manifestations. SSc is classified into limited cutaneous SSc (lcSSc) and diffuse cutaneous subgroups (dcSSc) based on the extent of skin involvement. Randomized controlled trials in scleroderma have mainly focused on dcSSc partly because the measurement of skin involvement, critical for evaluating a therapeutic intervention is more dynamic in this subset. Nonetheless, lcSSc, the most common cutaneous subset (about 2/3), is also associated with significant morbidity and detrimental impact on health-related quality of life. The lack of interventional studies in lcSSc is partly due to a lack of relevant outcome measures to evaluate this subgroup. Combining several clinically meaningful outcomes selected specifically for lcSSc may improve representativeness in clinical trials and responsiveness of outcomes measured in randomized controlled trials. A composite index dedicated to lcSSc combining such relevant outcomes could advance clinical trial development for lcSSc by providing the opportunity to test and select among candidate drugs that could act as disease-modifying treatments for this neglected subgroup of SSc. This proposed index would include items selected by expert physicians and patients with lcSSc across domains grounded in the lived experience of lcSSc. This article reviews the reasons behind the relative neglect of lcSSc, discusses the current state of outcome measures for lcSSc, identifies challenges, and proposes a roadmap for a combined lcSSc-specific treatment response index.

Emerging drugs for the treatment of scleroderma: a review of recent phase 2 and 3 trials

INTRODUCTION

Systemic sclerosis (SSc) has the highest case-specific mortality of all connective tissue diseases. Its underlying disease mechanism affects several organs and remains incompletely understood. Ongoing work clarifying its etiopathogenesis is helping to develop targeted therapy.

AREAS COVERED

Several clinical trials have evaluated the safety and efficacy of agents targeting different mechanisms of this disease. This review article reviews those mechanisms and surveys four key recent phase II or III clinical trials that are contributing to the landscape of SSc therapy. The reported trials primarily focus on patients with systemic sclerosis in the early phase of disease.

EXPERT OPINION

Traditional therapies for SSc center on immunosuppressive and cytotoxic agents. A new cadre of therapies is borne from improved understandings of SSc pathobiology and target the inflammatory-fibrotic pathways. Scleroderma trials have entered the initial phase of personalized medicine, recognizing molecular subsets that will improve upon cohort enrichment and maximize the measurable benefit of future therapies.

Lung magnetic resonance imaging in systemic sclerosis: a new promising approach to evaluate pulmonary involvement and progression

INTRODUCTION/OBJECTIVES

Interstitial lung disease (ILD) is frequent and highly disabling in systemic sclerosis (SSc). Magnetic resonance imaging (MRI) is not routinely used to evaluate the lung, due to poorer spatial resolution compared to high-resolution computed tomography (HRCT). We aimed to compare lung MRI signal with HRCT and evaluate the role of MRI in predicting ILD progression.

METHODS

Thirty SSc patients underwent lung MRI and HRCT. STIR and T1 mapping sequences were acquired before and after gadolinium injection. Patients were classified as normal (group 1 with normal HRCT and MRI), discordant (group 2 without ILD signs on HRCT but areas of hyperintensity on MRI), and abnormal (group 3 with ILD signs on HRCT and areas of hyperintensity on MRI). Patients were followed up for ILD progression.

RESULTS

Mean STIR and T1 values were different between the three groups (p < 0.0001). STIR values correlated with HRCT score (R = 0.79, p < 0.0001), lung ultrasound B-lines (R = 0.73, p < 0.0001), and %DLco (R = - 0.63, p = 0.0001). Nine events were recorded during a follow-up of 25 ± 20 months. Continuous STIR values were independently associated with events (HR 1.018; CI 1.005-1.031, p = 0.005). A STIR value >90 ms discriminated patients at a higher risk of worsening pulmonary involvement (HR 8.80; CI 1.81-42.74; p < 0.007).

CONCLUSIONS

Lung MRI can detect SSc-related ILD, with good correlations with other ILD markers. STIR values, independently of HRCT appearance, may predict worsening lung involvement. Lung MRI, although very preliminary, is a promising tool that in a near future could help selecting patients for an early treatment of SSc-related ILD and a more appropriate use of HRCT. Key points • Lung MRI has the potential to differentiate inflammation-predominant versus fibrosis-predominant lesions, but it is not currently used in routine clinical practice to assess SSc-related ILD. • Lung MRI STIR and T1 values are significantly different between patients with and without SSc-related ILD. STIR values, independently of HRCT appearance, are also able to predict worsening lung involvement over time. • These preliminary data suggest that, in a near future, MRI could support the choice for an early treatment of SSc-related ILD, as well as a more appropriate use of HRCT.

Mitochondria, Aging, and Cellular Senescence: Implications for Scleroderma

PURPOSE OF REVIEW

The etiology of systemic sclerosis (SSc), which is a rare immune-mediated inflammatory disease characterized by vascular damage and fibrosis, is still unknown. However, different intrinsic (genetics) and extrinsic (environmental) factors play a part in the progression of the disease. This review focuses on the role of aging, mitochondrial dysfunction, and senescence in SSc.

RECENT FINDINGS

Mitochondrial dysfunction and senescence have been linked to the age-related susceptibility to other interstitial lung diseases (ILD) such as idiopathic pulmonary fibrosis (IPF). SSc is not regarded as an age-related disease but does show a higher incidence of cardiac events, fibrosis, and mortality at older age. We provide an overview of the current status of the role of aging, mitochondrial dysfunction, and senescence in SSc. Further work is needed to validate some of these pathways in SSc and may allow for new therapeutic interventions focused on restoring mitochondrial homeostasis and the targeted removal of chronic-senescent cells.