Tofacitinib as a Steroid-Sparing Therapy in Pulmonary Sarcoidosis, an Open-Label Prospective Proof-of-Concept Study

Clinical trials in pulmonary sarcoidosis; what is needed, what is happening and what is next?

PURPOSE OF REVIEW

There is a clinical unmet need to improve treatment for patients with pulmonary sarcoidosis. Both retrospective and prospective drug trials are hampered by the fact that patients with sarcoidosis are characterized by a heterogeneous presentation and disease course. In this review, an overview is given of different drug trials in pulmonary sarcoidosis with an emphasis on different primary endpoints and the problems related to them.

RECENT FINDINGS

In recent years, using significant input from patients with sarcoidosis, different task-forces/studies tried to develop a core set of most important outcomes to measure in future studies on treatment of sarcoidosis. Furthermore, at present, three major clinical trials are being conducted on new drugs for treatment of pulmonary sarcoidosis.

SUMMARY

Progress has been made to develop a core set of outcomes measures that can be used in making a combined primary endpoint in future drug trials in sarcoidosis.

Bioinformatic meta-analysis reveals novel differentially expressed genes and pathways in sarcoidosis

Introduction

Sarcoidosis is a multi-system inflammatory disease of unknown origin with heterogeneous clinical manifestations varying from a single organ non-caseating granuloma site to chronic systemic inflammation and fibrosis. Gene expression studies have suggested several genes and pathways implicated in the pathogenesis of sarcoidosis, however, due to differences in study design and variable statistical approaches, results were frequently not reproducible or concordant. Therefore, meta-analysis of sarcoidosis gene-expression datasets is of great importance to robustly establish differentially expressed genes and signalling pathways.

Methods

We performed meta-analysis on 22 published gene-expression studies on sarcoidosis. Datasets were analysed systematically using same statistical cut-offs. Differentially expressed genes were identified by pooling of p-values using Edgington's method and analysed for pathways using Ingenuity Pathway Analysis software.

Results

A consistent and significant signature of novel and well-known genes was identified, those collectively implicated both type I and type II interferon mediated signalling pathways in sarcoidosis. In silico functional analysis showed consistent downregulation of eukaryotic initiation factor 2 signalling, whereas cytokines like interferons and transcription factor STAT1 were upregulated. Furthermore, we analysed affected tissues to detect differentially expressed genes likely to be involved in granuloma biology. This revealed that matrix metallopeptidase 12 was exclusively upregulated in affected tissues, suggesting a crucial role in disease pathogenesis.

Discussion

Our analysis provides a concise gene signature in sarcoidosis and expands our knowledge about the pathogenesis. Our results are of importance to improve current diagnostic approaches and monitoring strategies as well as in the development of targeted therapeutics.

Insights into the diagnosis and management of sarcoid uveitis: A review

Sarcoidosis is a leading cause of non-infectious uveitis that commonly affects middle-aged individuals and has a female preponderance. The disease demonstrates age, sex and ethnic differences in clinical manifestations. A diagnosis of sarcoidosis is made based on a compatible clinical presentation, supporting investigations and histologic evidence of non-caseating granulomas, although biopsy is not always possible. Multimodal imaging with widefield fundus photography, optical coherence tomography and angiography can help in the diagnosis of sarcoid uveitis and in the monitoring of treatment response. Corticosteroid remains the mainstay of treatment; chronic inflammation requires steroid-sparing immunosuppression. Features on multimodal imaging such as vascular leakage may provide prognostic indicators of outcome. Female gender, prolonged and severe uveitis, and posterior involving uveitis are associated with poorer visual outcomes.

Neurosarcoidosis and Neurologic Complications of Sarcoidosis Treatment

Sarcoidosis is an immune-mediated multisystem granulomatous disorder. Neurosarcoidosis (NS) accounts for 5% to 35% of cases. The diagnostic evaluation of NS can be a clinical challenge. Gadolinium-enhanced magnetic resonance imaging (MRI) is the gold standard to evaluate central nervous system NS. In almost all cases treatment is warranted. Although glucocorticoids remain the first-line therapy in patients with sarcoidosis, in NS timely initiation of second- or third-line treatment is strongly recommended. Of these, tumor necrosis factor-alpha inhibitors are the most promising. However, the treatment itself may be responsible for/associated with developing neurologic symptoms mimicking NS. Thus, it is important to consider the possibility of drug-induced neurologic symptoms in sarcoidosis.

Anti-inflammatory Therapy for Sarcoidosis

Over 50% of patients with sarcoidosis will require anti-inflammatory therapy at some point in their disease course. Indications for therapy are to improve health-related quality of life, prevent or arrest organ dysfunction (or organ failure) or avoid death. Recently published treatment guidelines recommended a stepwise approach to therapy however there are some patients for whom up front combination or more intense therapy maybe reasonable. The last decade has seen an explosion of studies and trials evaluating novel therapeutic agents and treatment strategies. Currently available anti-inflammatory therapies and several novel therapies are discussed here.

Quality of life in sarcoidosis

Having sarcoidosis often has a major impact on quality of life of patients and their families. Improving quality of life is prioritized as most important treatment aim by many patients with sarcoidosis, but current evidence and treatment options are limited. In this narrative review, we describe the impact of sarcoidosis on various aspects of daily life, evaluate determinants of health-related quality of life (HRQoL), and provide an overview of the different patient-reported outcome measures to assess HRQoL in sarcoidosis. Moreover, we review the current evidence for pharmacological and non-pharmacological interventions to improve quality of life for people with sarcoidosis.

Molecularly Targeted Therapies for Inflammatory Cutaneous Granulomatous Disorders: A Review of the Evidence and Implications for Understanding Disease Pathogenesis

Inflammatory cutaneous granulomatous diseases, including granuloma annulare, cutaneous sarcoidosis, and necrobiosis lipoidica, are distinct diseases unified by the hallmark of macrophage accumulation and activation in the skin. There are currently no Food and Drug Administration-approved therapies for these conditions except prednisone and repository corticotropin injection for pulmonary sarcoidosis. Treatment of these diseases has generally been guided by low-quality evidence and may involve broadly immunomodulatory medications. Development of new treatments has in part been limited by an incomplete understanding of disease pathogenesis. Recently, there has been substantial progress in better understanding the molecular pathogenesis of these disorders, opening the door for therapeutic innovation. Likewise, reported outcomes of treatment with immunologically targeted therapies may offer insights into disease pathogenesis. In this systematic review, we summarize progress in deciphering the pathomechanisms of these disorders and discuss this in the context of emerging evidence on the use of molecularly targeted therapies in treatment of these diseases.

Simultaneous Assessment of mTORC1, JAK/STAT, and NLRP3 Inflammasome Activation Pathways in Patients with Sarcoidosis

The unknown etiology of sarcoidosis, along with the variability in organ involvement and disease course, complicates the effective treatment of this disease. Based on recent studies, the cellular inflammatory pathways involved in granuloma formation are of interest regarding possible new treatment options, such as the mechanistic (formerly mammalian) target of rapamycin complex 1 (mTORC1) pathway, the Janus kinase/signal transducers and activators of transcription (JAK/STAT) pathway, and the nucleotide-binding domain, leucine-rich-containing family, pyrin domain-containing-3 (NLRP3) inflammasome pathway. The aim of this study was to explore the potential coexpression of these three inflammatory pathways in patients with sarcoidosis and see whether possible differences were related to disease outcome. The tissue of 60 patients with sarcoidosis was used to determine the activity of these three signaling pathways using immunohistochemistry. The activation of NLRP3 was present in 85% of all patients, and the activation of mTORC1 and JAK/STAT was present in 49% and 50% of patients, respectively. Furthermore, the presence of NLRP3 activation at diagnosis was associated with a chronic disease course of sarcoidosis. Our finding of different new conceptual inflammatory tissue phenotypes in sarcoidosis could possibly guide future treatment studies using the available inhibitors of either NLRP3, JAK-STAT, and mTORC1 inhibitors in a more personalized medicine approach.

Tofacitinib, a suppressor of NOD2 expression, is a potential treatment for Blau syndrome

Introduction

Blau syndrome is a rare autosomal dominant autoinflammatory granulomatous disease caused by a mutation in the NOD2 gene. It is characterized by a clinical trial of granulomatous dermatitis, arthritis, and uveitis. Tofacitinib is a pan Janus kinase (JAK) inhibitor used for treatment of Blau syndrome and idiopathic sarcoidosis. Here, we evaluated its effect on inflammatory pathways associated with Blau syndrome. The effect of tofacitinib on downstream pathways regulated by mutant NOD2 was analyzed using luciferase assays with overexpression of NOD2 mutants.

Methods

The effect of tofacitinib on the upstream pathway for the induction of NOD2 expression and proinflammatory cytokine production was assessed using monocytic cell lines differentiated from Blau syndrome patient-derived induced pluripotent stem cells.

Results

Tofacitinib did not suppress the increased spontaneous transcriptional activity of NF-κB by mutant NOD2. In addition, mutant NOD2 was not involved in the transcription of ISRE and GAS, which are activated by type 1 and type 2 interferons (IFN), respectively. On the other hand, IFNγ induced the expression of NOD2, which led to the production of inflammatory cytokines by an autoinflammatory mechanism only in cells with mutant NOD2.

Discussion

Tofacitinib suppressed the induction of NOD2 by IFNγ, thereby inhibiting the production of pro-inflammatory cytokines. Thus, tofacitinib showed anti-inflammatory effects through suppression of NOD2 expression. The JAK inhibitor tofacitinib is a potential therapeutic agent for Blau syndrome because it suppresses the autoinflammation seen in Blau syndrome by inhibiting the expression of NOD2.

[Sarcoidosis]

Sarcoidosis is the most common granulomatous disease in northern Europe. A distinction is made between acute forms of sarcoidosis and chronic sarcoidosis. Chronic sarcoidosis can affect practically all organs but the lungs are affected in 90-95% of patients. The clinical appearance varies between asymptomatic and oligosymptomatic courses, which are diagnosed more by chance, to courses with acute organ failure. An extensive organ work-up is necessary at the time of the initial diagnosis in order to record the extent of organ involvement and to make appropriate treatment decisions. Asymptomatic courses with purely pulmonary sarcoidosis do not require treatment and can be observed over the course of the disease, whereas courses with extensive organ involvement or organ dysfunction require treatment. The treatment consists primarily of the administration of glucocorticoids. If the effect of the glucocorticoids is insufficient or if there are side effects, various immunosuppressive agents, including biologics can be added.

Sarcoidosis-Related Uveitis: A Review

Sarcoidosis is an inflammatory disease that involves the eyes in 10-55% of cases, sometimes without systemic involvement. All eye structures can be affected, but uveitis is the most common ocular manifestation and causes vision loss. The typical ophthalmological appearance of these uveitis is granulomatous (in cases with anterior involvement), which are usually bilateral and with synechiae. Posterior involvement includes vitritis, vasculitis and choroidal lesions. Tuberculosis is a classic differential diagnosis to be wary of, especially in people who have spent time in endemic areas. The diagnosis is based on histology with the presence of non-caseating epithelioid granulomas. However, due to the technical difficulty and yield of biopsies, the diagnosis of ocular sarcoidosis is often based on clinico-radiological features. The international criteria for the diagnosis of ocular sarcoidosis have recently been revised. Corticosteroids remain the first-line treatment for sarcoidosis, but up to 30% of patients require high doses, justifying the use of corticosteroid-sparing treatments. In these cases, immunosuppressive treatments such as methotrexate may be introduced. More recent biotherapies such as anti-TNF are also very effective (as they are in other non-infectious uveitis etiologies).

[Sarcoid uveitis: Ophthalmologist's and internist's viewpoints]

Sarcoidosis is one of the leading causes of inflammatory eye disease. All ocular structures can be affected, but uveitis is the main manifestation responsible for vision loss in ocular sarcoidosis. Typical sarcoid anterior uveitis presents with mutton-fat keratic precipitates, iris nodules, and posterior synechiae. Posterior involvement includes vitritis, vasculitis, and choroidal lesions. Cystoid macular edema is the most important and sight-threatening consequence of sarcoid uveitis. Patients with clinically isolated uveitis at diagnosis rarely develop other organ involvement. Even though, ocular sarcoidosis can have a severe impact on visual prognosis, early diagnosis and a wider range of available therapies (including intravitreal implants) have lessened the functional impact of the disease, particularly in the last decade. Corticosteroids are the cornerstone of treatment for sarcoidosis, but up to 30% of patients achieve remission with requiring high-dose systemic steroids. In these cases, the use of steroid-sparing immunosuppressive therapy (such as methotrexate) is unavoidable. Among these immunosuppressive treatments, anti TNF-α drugs have been a revolution in the management of non-infectious uveitis.

Sarcoidosis: Updates on therapeutic drug trials and novel treatment approaches

Sarcoidosis is a systemic granulomatous inflammatory disease of unknown etiology. It affects the lungs in over 90% of patients yet extra-pulmonary and multi-organ involvement is common. Spontaneous remission of disease occurs commonly, nonetheless, over 50% of patients will require treatment and up to 30% of patients will develop a chronic progressive non-remitting disease with marked pulmonary fibrosis leading to significant morbidity and death. Guidelines outlining an immunosuppressive treatment approach to sarcoidosis were recently published, however, the strength of evidence behind many of the guideline recommended drugs is weak. None of the drugs currently used for the treatment of sarcoidosis have been rigorously studied and prescription of these drugs is often based on off-label” indications informed by experience with other diseases. Indeed, only two medications [prednisone and repository corticotropin (RCI) injection] currently used in the treatment of sarcoidosis are approved by the United States Food and Drug Administration. This situation results in significant reimbursement challenges especially for the more advanced (and often more effective) drugs that are favored for severe and refractory forms of disease causing an over-reliance on corticosteroids known to be associated with significant dose and duration dependent toxicities. This past decade has seen a renewed interest in developing new drugs and exploring novel therapeutic pathways for the treatment of sarcoidosis. Several of these trials are active randomized controlled trials (RCTs) designed to recruit relatively large numbers of patients with a goal to determine the safety, efficacy, and tolerability of these new molecules and therapeutic approaches. While it is an exciting time, it is also necessary to exercise caution. Resources including research dollars and most importantly, patient populations available for trials are limited and thus necessitate that several of the challenges facing drug trials and drug development in sarcoidosis are addressed. This will ensure that currently available resources are judiciously utilized. Our paper reviews the ongoing and anticipated drug trials in sarcoidosis and addresses the challenges facing these and future trials. We also review several recently completed trials and draw lessons that should be applied in future.

Neurosarcoidosis: an update on diagnosis and therapy

INTRODUCTION

Clinically overt granulomatous involvement of the nervous system (i.e., neurosarcoidosis) can be seen in up to 10% of patients with sarcoidosis. Establishing a diagnosis of neurosarcoidosis is often challenging due to the heterogeneity of clinical presentations that are sometimes non-specific, and inaccessibility of tissue confirmation. Recommended treatments are based on expert opinions that are derived from clinical experience and limited data from retrospective studies, as data from randomized controlled studies are limited.

AREA COVERED

In this article, we comprehensively review all available literature on epidemiology, clinical presentations, diagnosis, treatment, and outcomes of neurosarcoidosis. We also offer our opinions on diagnostic approach and treatment strategy.

EXPERT OPINION

Given the invasive nature and the limited sensitivity of biopsy of the nervous system, diagnosis of neurosarcoidosis is usually made when ancillary tests (such as magnetic resonance imaging and cerebrospinal fluid analysis) are compatible, and alternative diagnoses are reasonably excluded in patients with established extraneural sarcoidosis. Several factors must be taken into consideration to formulate the initial treatment strategy, including the extent of the disease, severity, functional impairment, comorbidities and patient's preference. In addition, treatment regimen of neurosarcoidosis should be formulated with an emphasis on long-term strategy.

The Evolving Landscape of Cutaneous Sarcoidosis: Pathogenic Insight, Clinical Challenges, and New Frontiers in Therapy

Sarcoidosis is a multisystem disorder of unknown etiology characterized by accumulation of granulomas in affected tissue. Cutaneous manifestations are among the most common extrapulmonary manifestations in sarcoidosis and can lead to disfiguring disease requiring chronic therapy. In many patients, skin disease may be the first recognized manifestation of sarcoidosis, necessitating a thorough evaluation for systemic involvement. Although the precise etiology of sarcoidosis and the pathogenic mechanisms leading to granuloma formation, persistence, or resolution remain unclear, recent research has led to significant advances in our understanding of this disease. This article reviews recent advances in epidemiology, sarcoidosis clinical assessment with a focus on the dermatologist's role, disease pathogenesis, and new therapies in use and under investigation for cutaneous and systemic sarcoidosis.

State-of-the-Art Treatments for Sarcoidosis

Sarcoidosis is a heterogeneous disease with various treatment indications. Although it affects mainly the lungs, sarcoidosis can affect every organ, especially when the disease course is chronic and protracted. Regular patient follow-up is recommended for early recognition of active, ongoing organ-specific granulomatous inflammation to avoid progression to irreversible fibrosis. In this review, we elaborate on treatment indications and various anti-sarcoidosis regimens proven useful in clinical trials. We also review specialized treatment of specific disease manifestations, with a focus on cardiac sarcoidosis. We also report on treatment for special conditions such as fatigue and small fiber neuropathy. Treatment for sarcoidosis is an emerging landscape, with new data complementing the existing knowledge.