Tofacitinib Treatment and Molecular Analysis of Cutaneous Sarcoidosis

Sarcoidosis and the mTOR, Rac1, and Autophagy Triad

Sarcoidosis is an enigmatic multisystem disease characterized by the development and accumulation of granulomas: a compact collection of macrophages that have differentiated into epithelioid cells and which are associated with T helper (Th)1 and Th17 cells. Although no single causative factor has been shown to underlie sarcoidosis in humans, its etiology has been related to microbial, environmental, and genetic factors. We examine how these factors play a role in sarcoidosis pathogenesis. Specifically, we propose that dysfunction of mTOR, Rac1, and autophagy-related pathways not only hampers pathogen or nonorganic particle clearance but also participates in T cell and macrophage dysfunction, driving granuloma formation. This concept opens new avenues for potentially treating sarcoidosis and may serve as a blueprint for other granulomatous disorders.

Therapeutic strategies for pulmonary sarcoidosis

Introduction: The treatment of pulmonary sarcoidosis is not standardized. Treatment involves a multi-step decision process beginning with whether treatment is warranted, determining initial therapy, then assessing when therapy requires modifications or can be discontinued.Areas covered: This manuscript will address the following issues concerning the treatment of pulmonary sarcoidosis: Treatment indications, initial anti-granulomatous therapy, therapy for chronic and fibrotic disease, glucocorticoid therapy, alternative therapy to glucocorticoids, non-granulomatous therapies, and managing complications of disease. Information was obtained through a literature search of PubMed and Web of Science databases.Expert opinion: Although glucocorticoids are highly effective for pulmonary sarcoidosis, their potential to cause significant side effects often mandates consideration of alternative agents. As the most common indication for the treatment of pulmonary sarcoidosis is quality of life impairment, traditional objective tests of lung function and radiographic imagining often have a minor role in therapeutic decision-making. The development of pulmonary fibrosis from sarcoidosis often causes major morbidity and mortality and should be a major focus of concern.

Treatment of Multiorgan Sarcoidosis With Tofacitinib

Objective

Sarcoidosis is an idiopathic inflammatory disorder that is difficult to treat. There is accumulating evidence that constitutive activation of Janus kinase–signal transducer and activator of transcription (JAK‐STAT) signaling occurs in sarcoidosis and represents a target for treatment. Here we report the efficacy of tofacitinib, a Janus kinase (JAK) inhibitor, in a single patient with multiorgan sarcoidosis.

Methods

A patient with long‐standing multiorgan sarcoidosis who was unresponsive to other commonly used therapies, including methotrexate, prednisone, and tumor necrosis factor α blockade, was treated with tofacitinib.

Results

Tofacitinib treatment resulted in clinical remission of cutaneous sarcoidosis lesions and resolution of positron emission tomography avid lesions in internal organs after 6 months. An evaluation of lesional tissue and blood before and during treatment showed resolution of granulomatous inflammation and normalization of disease biomarkers.

Conclusion

This case illustrates the promise of JAK inhibition as a strategy to treat recalcitrant sarcoidosis and suggests that further study of JAK inhibitors in sarcoidosis is needed.

Knowing when to use steroids, immunosuppressants or biologics for the treatment of sarcoidosis

Introduction: Care of patients with sarcoidosis requires familiarity with its natural history as well as of various immunosuppressants employed in its treatment. We would like to share our approach to management based on our experience and understanding of the relevant literature.Areas covered: Asymptomatic patients with pulmonary sarcoidosis ought to be managed conservatively. Systemic sarcoidosis with burdensome symptoms usually responds to corticosteroids, but one needs to consider the risk of long-term steroid toxicity as well as relapse. Rapidly tapering steroids can decrease cumulative exposure without compromising efficacy. Steroid-sparing anti-sarcoidosis (SSAS) agents take longer to act and are associated with unique but mostly reversible toxicities. Used judiciously and with careful monitoring, they effectively suppress granulomatous inflammation. Patients intolerant of or failing to improve with a particular drug can be switched to another, and occasionally combination therapy with two SSAS agents might prove effective. A small proportion of patients are refractory, but often achieve control and sometimes remission with stepping up to biologic therapy.Expert opinion: Adopting a strategy of early SSAS therapy ought to effectively control sarcoidosis and avoid harm from prolonged corticosteroid dosing.

Emerging Topical and Systemic JAK Inhibitors in Dermatology

Accumulating data on cellular and molecular pathways help to develop novel therapeutic strategies in skin inflammation and autoimmunity. Examples are psoriasis and atopic dermatitis, two clinically and immunologically well-defined disorders. Here, the elucidation of key pathogenic factors such as IL-17A/IL-23 on the one hand and IL-4/IL-13 on the other hand profoundly changed our therapeutic practice. The knowledge on intracellular pathways and governing factors is shifting our attention to new druggable molecules. Multiple cytokine receptors signal through Janus kinases (JAKs) and associated signal transducer and activators of transcription (STATs). Inhibition of JAKs can simultaneously block the function of multiple cytokines. Therefore, JAK inhibitors (JAKi) are emerging as a new class of drugs, which in dermatology can either be used systemically as oral drugs or locally in topical formulations. Inhibition of JAKs has been shown to be effective in various skin disorders. The first oral JAKi have been recently approved for the treatment of rheumatoid arthritis and psoriatic arthritis. Currently, multiple inhibitors of the JAK/STAT pathway are being investigated for skin diseases like alopecia areata, atopic dermatitis, dermatomyositis, graft-versus-host-disease, hidradenitis suppurativa, lichen planus, lupus erythematosus, psoriasis, and vitiligo. Here, we aim to discuss the immunological basis and current stage of development of JAKi in dermatology.

New advances in the management of pulmonary sarcoidosis

Sarcoidosis is a highly variable granulomatous multisystem syndrome. It affects individuals in the prime years of life; both the frequency and severity of sarcoidosis are greater in economically disadvantaged populations. The diagnosis, assessment, and management of pulmonary sarcoidosis have evolved as new technologies and therapies have been adopted. Transbronchial needle aspiration guided by endobronchial ultrasound has replaced mediastinoscopy in many centers. Advanced imaging modalities, such as fluorodeoxyglucose positron emission tomography scanning, and the widespread availability of magnetic resonance imaging have led to more sensitive assessment of organ involvement and disease activity. Although several new insights about the pathogenesis of sarcoidosis exist, no new therapies have been specifically developed for use in the disease. The current or proposed use of immunosuppressive medications for sarcoidosis has been extrapolated from other disease states; various novel pathways are currently under investigation as therapeutic targets. Coupled with the growing recognition of corticosteroid toxicities for managing sarcoidosis, the use of corticosteroid sparing anti-sarcoidosis medications is likely to increase. Besides treatment of granulomatous inflammation, recognition and management of the non-granulomatous complications of pulmonary sarcoidosis are needed for optimal outcomes in patients with advanced disease.

Metabolic Programming of Macrophages: Implications in the Pathogenesis of Granulomatous Disease

Metabolic reprogramming is rapidly gaining appreciation in the etiology of immune cell dysfunction in a variety of diseases. Tuberculosis, schistosomiasis, and sarcoidosis represent an important class of diseases characterized by the formation of granulomas, where macrophages are causatively implicated in disease pathogenesis. Recent studies support the incidence of macrophage metabolic reprogramming in granulomas of both infectious and non-infectious origin. These publications identify the mechanistic target of rapamycin (mTOR), as well as the major regulators of lipid metabolism and cellular energy balance, peroxisome proliferator receptor gamma (PPAR-γ) and adenosine monophosphate-activated protein kinase (AMPK), respectively, as key players in the pathological progression of granulomas. In this review, we present a comprehensive breakdown of emerging research on the link between macrophage cell metabolism and granulomas of different etiology, and how parallels can be drawn between different forms of granulomatous disease. In particular, we discuss the role of PPAR-γ signaling and lipid metabolism, which are currently the best-represented metabolic pathways in this context, and we highlight dysregulated lipid metabolism as a common denominator in granulomatous disease progression. This review therefore aims to highlight metabolic mechanisms of granuloma immune cell fate and open up research questions for the identification of potential therapeutic targets in the future.

Off-label studies on tofacitinib in dermatology: a review

PURPOSE

Tofacitinib citrate is an oral Janus kinase 1/3 inhibitor approved for rheumatoid arthritis, ulcerative colitis, and active psoriatic arthritis. Tofacitinib is being increasingly used off-label for dermatological conditions, with varying efficacy across recent studies. A review of these studies will be a helpful resource for dermatologists considering the use of tofacitinib for conditions refractory to first-line therapies.

MATERIALS AND METHODS

MEDLINE, Embase, CINAHL Plus, Cochrane Library, Scopus, Web of Science, Clinicaltrials.gov, and the WHO International Clinical Trials Registry Platform were all searched for articles and trials mentioning the term 'tofacitinib', then manually reviewed to identify published data on off-label uses of tofacitinib. The article was structured according to the quality of the evidence available.

RESULTS

Tofacitinib appears to show strong efficacy for numerous dermatologic conditions. Randomized controlled trial data is available for atopic dermatitis, alopecia areata, and plaque psoriasis. Case report and case series data is available for numerous other dermatologic conditions.

CONCLUSION

While tofacitinib has a wide array of immunoregulatory properties, making it a possible candidate for treating many dermatologic conditions refractory to other treatments, further testing is needed to better characterize its efficacy and utility moving forward, as well as its safety and adverse effect profile.

JAK inhibitors for the treatment of autoimmune and inflammatory diseases

Cytokines play a central role in the pathophysiology of autoimmune and inflammatory diseases. Several cytokines signal through the JAK-STAT pathway, which is now recognized as a major target to inhibit the effect of a wide array of cytokines. JAK inhibitors are increasingly used in the setting of inflammatory and autoimmune diseases. While the currently approved drugs are panJAK inhibitors, more selective small molecules are being developed and tested in various rheumatic disorders. In this extensive review, we present evidence- or hypothesis-based perspectives for these drugs in various rheumatologic conditions, such as rheumatoid arthritis, systemic lupus erythematosus, giant cell arteritis, and autoinflammatory diseases.

Sarcoidosis

Sarcoidosis is an inflammatory disorder of unknown cause that is characterized by granuloma formation in affected organs, most often in the lungs. Patients frequently suffer from cough, shortness of breath, chest pain and pronounced fatigue and are at risk of developing lung fibrosis or irreversible damage to other organs. The disease develops in genetically predisposed individuals with exposure to an as-yet unknown antigen. Genetic factors affect not only the risk of developing sarcoidosis but also the disease course, which is highly variable and difficult to predict. The typical T cell accumulation, local T cell immune response and granuloma formation in the lungs indicate that the inflammatory response in sarcoidosis is induced by specific antigens, possibly including self-antigens, which is consistent with an autoimmune involvement. Diagnosis can be challenging for clinicians because of the potential for almost any organ to be affected. As the aetiology of sarcoidosis is unknown, no specific treatment and no pathognomic markers exist. Thus, improved biomarkers to determine disease activity and to identify patients at risk of developing fibrosis are needed. Corticosteroids still constitute the first-line treatment, but new treatment strategies, including those targeting quality-of-life issues, are being evaluated and should yield appropriate, personalized and more effective treatments.

Janus kinase inhibition induces disease remission in cutaneous sarcoidosis and granuloma annulare

BACKGROUND

Sarcoidosis and granuloma annulare (GA) are cutaneous granulomatous disorders that can be difficult to treat. There is evidence of underlying Janus kinase (JAK)-signal transducer and activator of transcription (STAT) pathway activation in sarcoidosis, suggesting that JAK inhibition might be effective.

OBJECTIVE

To evaluate treatment with tofacitinib, a JAK inhibitor, in patients with recalcitrant sarcoidosis and GA.

METHODS

A prospective evaluation of tofacitinib in 4 consecutive patients with recalcitrant cutaneous sarcoidosis (n = 3) and generalized GA (n = 1) was conducted. Immunohistochemical analysis of skin biopsy specimens from other patients with sarcoidosis (n = 21) and GA (n = 17) was performed to characterize patterns of JAK-STAT pathway activation.

RESULTS

Tofacitinib resulted in a mean improvement in the baseline Cutaneous Sarcoidosis Activity and Morphology Instrument and Granuloma Annulare Scoring Index scores of 96% (standard deviation, 2%). Histologic resolution of disease was documented in all patients (3 out of 3) who had skin biopsies while receiving therapy. Constitutive STAT1 and STAT3 activation was observed in both sarcoidosis and GA, albeit in different patterns. Signal regulatory protein α may explain the differences in JAK-STAT signaling between sarcoidosis and GA.

LIMITATIONS

The study is limited by the small number of participants.

CONCLUSIONS

Tofacitinib resulted in dramatic improvement in 4 patients with cutaneous sarcoidosis and GA. Larger studies are underway to better understand this effect.

Biologic Therapy in the Treatment of Cutaneous Sarcoidosis: A Literature Review

Sarcoidosis is an inflammatory disease defined by the presence of non-caseating granulomas. It can affect a number of organ systems, most commonly the lungs, lymph nodes, and skin. Cutaneous manifestations of sarcoidosis can impose a significant detriment to patients' quality of life. The accepted first-line therapy for cutaneous sarcoidosis consists of intralesional and oral corticosteroids, but these can fail in the face of resistant disease and corticosteroid-induced adverse effects. Second-line agents include tetracyclines, hydroxychloroquine, and methotrexate. Biologics are an emerging treatment option for the management of cutaneous sarcoidosis, but their role in management is not well-defined. In this article, we reviewed the currently available English-language publications on the use of biologics in managing cutaneous sarcoidosis. Although somewhat limited, the data in published studies support the use of both infliximab and adalimumab as third-line treatments for chronic or resistant cutaneous sarcoidosis. There were also scattered reports of etanercept, rituximab, golimumab, and ustekinumab being utilized as third-line agents with varying degrees of success. Larger and more extensive investigations are required to further assess the adverse effect profile and optimal dosing for managing cutaneous sarcoidosis.

Tofacitinib for the treatment of rheumatoid arthritis: an update

INTRODUCTION

Tofacitinib inhibits the Janus kinases, tyrosine kinases that are activated by cytokines involved in the pathophysiology of rheumatoid arthritis. Areas covered: Clinical trials have revealed an anti-rheumatic effect of monotherapy and combination therapy with methotrexate (MTX). Post-hoc analysis of those clinical trials and real-world experiences will be reviewed to explore efficacy and safety. Expert commentary: The efficacy of tofacitinib monotherapy has garnered much attention and has been initiated in large number of patients. However, combination therapy with MTX is necessary in order to achieve the maximum effect. Combination therapy can be transferred to monotherapy by tapering and/or discontinuing MTX. The discontinuation of tofacitinib should be avoided and tapering should be investigated. There has been no new safety signal although venous thrombotic events (VTEs) have been raised and would require long-term follow-up. Increased events of Herpes zoster were observed and the use of a subunit vaccination is expected to become an effective tool for prevention. Post-hoc analysis of the clinical trials and real-world experience is revealing further usefulness of tofacitinib not only in rheumatoid arthritis but also other diseases. Additional experience and data from the real world are required to help improve the use of tofacitinib..

Janus kinase inhibitors in immuno-inflammatory rheumatic diseases: new opportunities and prospects

Despite the great success in the diagnosis and treatment of immuno-inflammatory rheumatic diseases (IIRD), which led to a significant improvement in the prognosis in many patients, the fundamental medical problems of this pathology – the restoration of quality of life and reduction of mortality to the population level – are far from solution. This served as a powerful impetus to the study of new approaches to pharmacotherapy of IIRD, one of which is associated with the use of low-molecular synthetic drugs that inhibit intracellular "signal" molecules-Janus kinase (JAK), the socalled Jakinibs. The current achievements and trends concerning the use of JAK inhibitors in the treatment of IIRD are considered.

Bilateral epibulbar pseudorheumatoid nodulosis with a review of ocular adnexal palisading granulomas

We describe the clinical, histopathologic, and immunohistochemical characteristics of episcleral/conjunctival pseudorheumatoid nodulosis, a new granulomatous entity that belongs among a group of related lesions. Specifically, pseudorheumatoid nodulosis should be differentiated from solitary rheumatoid nodules, rheumatoid nodulosis, accelerated rheumatoid nodules and nodulosis, and solitary pseudorheumatoid nodules. A 53-year-old man presented with bilateral painless, large, faintly yellow-gray, partially immobile, solid, circumscribed, and occasionally confluent episcleral nodules of several months' duration. He had never had clinical rheumatoid arthritis and was rheumatoid factor negative. Biopsy revealed multiple, merging episcleral/conjunctival, nonulcerated, palisading granulomas with variably sized central zones of necrobiosis of collagen. Abundant palisading CD68/163 + histiocytes admixed with fibroblasts surrounded the necrobiotic foci, which failed to stain with Alcian blue for mucopolysaccharides. No fibrinoid deposits were detected. Numerous CD3+ T lymphocytes, fewer CD 20 + B lymphocytes, and a smaller subpopulation of CD138 + plasma cells were present. Numerous CD1a + Langerhans cells were scattered among the palisading histiocytes and overlying epithelium. Immunohistochemical stains for immunoglobulins revealed concentrations of IgG, IgM, and IgA, but not IgE, in the necrobiotic zones. Special stains did not reveal evidence of infection nor did polarization microscopy display any foreign material. An extensive systemic and serologic workup was negative. We review simulating palisading or other nonrheumatic granulomas that should be distinguished from pseudorheumatoid nodules or nodulosis and explore therapeutic options.