JAK inhibitors in systemic lupus erythematosus: Translating pathogenesis into therapy.

Systemic lupus erythematosus (SLE) is a complex multi-organ autoimmune disease marked by the production of autoantibodies against nuclear structures, formation of immune complexes, and chronic inflammation triggered by their tissular deposition. SLE is characterized by alternating periods of relapse and remission and each flare has the potential to cause new organ damage related to either the disease process or the medication toxicity. Despite remarkable progress across its multiple domains, SLE is still an area with many unmet needs, calling for innovative and practical solutions. The efforts of the drug development programme in lupus have led to considerable growth in the last decade, owing to the approval of belimumab, anifrolumab, and voclosporin. The increasing understanding of the pathogenesis of the disease has enabled the exploration of novel therapeutic strategies. New discoveries in the intricate cytokine kaleidoscope of lupus have made the concept of targeted therapy an attractive and promising research focus. JAK inhibitors are oral targeted therapies approved for a wide variety of diseases across the Rheumatology, Gastroenterology, Dermatology, and Haematology fields. Multiple JAKis are currently being investigated in SLE. This paper aims to summarize existing data coming from both clinical trials and case reports regarding the use of JAK inhibitors in SLE.

Nonclinical evaluations of deucravacitinib and Janus kinase inhibitors in homeostatic and inflammatory pathways.

Translational medicine provides insight into novel drugs and predicts unwanted effects. In well-characterized pathways (e.g., cytokine-Janus kinase [JAK]-signal transducers and activators of transcription [STAT]), a variety of in vitro assessments were used to estimate selectivity of effects on different potential targets (i.e., JAK1, JAK2, JAK3, and tyrosine kinase 2 [TYK2]). Several approved drugs were characterized as selective for the JAK family. These assessments are challenged by a lack of compounds that only inhibit one JAK family member. Deucravacitinib is a first-in-class, oral, selective, allosteric inhibitor of TYK2, a kinase required for IL-12, IL-23, and Type I interferon signaling. Unlike deucravacitinib, which selectively binds to the TYK2 regulatory domain, JAK1,2,3 inhibitors target the catalytic domain, contributing to nonselective targeting of JAK1,2,3. Cytokines associated with JAK1,2,3 signaling are required for both immune and nonimmune functions. A similar laboratory abnormality profile was observed in clinical trials using JAK1,2,3 inhibitors that has not been observed with deucravacitinib. In vitro testing of JAK1,2,3 inhibitors has relied upon assays of signal transduction, such as those measuring STAT phosphorylation, for estimates of potency and selectivity. These assay systems can be effective in estimating in vivo efficacy; however, they may not provide insight into downstream outcomes of receptor signaling, which may be more relevant for evaluating safety aspects. Assay systems assessing functional outcomes from cells may yield a more useful translational evaluation. Here, deucravacitinib was assessed for potency and selectivity versus three representatives of the JAK inhibitor class (tofacitinib, baricitinib, and upadacitinib) based on functional assays. JAK inhibitors had suppressive activity against JAK2-dependent hematopoietic colony-forming assays modeling thrombopoiesis, erythropoiesis, and myelopoiesis; however, deucravacitinib did not. Deucravacitinib had limited potency against NK cells, cytotoxic T cells, T-helper cells, and regulatory T cells activated by JAK1/JAK3-dependent common gamma chain cytokines. These data are consistent with the biologic role of JAK1,2,3 and pharmacodynamic changes in clinical laboratory abnormalities. Against TYK2-dependent cytokines, deucravacitinib selectively inhibited Type I interferon stimulation of monocytes and dendritic cells and was a more potent inhibitor than JAK inhibitors. IL-12 and IL-23 functional outputs were similarly potently inhibited by deucravacitinib. Results are consistent with deucravacitinib selectively inhibiting TYK2.

Biologic and targeted synthetic disease-modifying anti-rheumatic drugs improve body composition in rheumatoid arthritis patients more than conventional synthetic disease-modifying anti-rheumatic drugs: Results from the PRESENT study.

INTRODUCTION: The effects of biologic and targeted synthetic disease-modifying anti-rheumatic drugs (b/tsDMARDs) and conventional synthetic disease-modifying anti-rheumatic drugs (csDMARDs) on body composition and muscle function in rheumatoid arthritis (RA) patients requiring treatment enhancement were compared. METHODS: This multicenter, prospective, observational study (PRESENT Study) divided RA patients non-randomly into a csDMARD group (n = 100) and a b/tsDMARD group (n = 100). Changes in body composition and muscle function were examined in 80 patients in each group followed for 52 weeks. The percentages of new-onset and improved sarcopenia over 1 year were investigated. Patients in the b/tsDMARD group were divided into three groups by drug type: TNF inhibitors (n = 30), non-TNF inhibitors (n = 23), and JAK inhibitors (n = 27). RESULTS: Baseline median age and disease duration were 70.0 and 4.0 years, respectively. Changes in weight (24 and 52 weeks) and muscle mass (52 weeks) were significantly higher in the b/tsDMARD group (p = .035, p < .001, and p = .002, respectively). On multivariate logistic regression analysis, b/tsDMARD treatment (OR 3.21, p = .002), DAS28-ESR (OR 0.65 p = .011), and muscle mass (OR 0.90, p = .023) were independently associated with increased muscle mass at 52 weeks. The percentages of new-onset and improved sarcopenia were almost equal. There were no significant differences in the time-dependent changes (52 weeks) of clinical status, body composition, muscle function, and status of sarcopenia among TNF inhibitors, non-TNF inhibitors, and JAK inhibitors. CONCLUSIONS: Weight and muscle mass increased significantly more with b/tsDMARD than with csDMARD treatment. There were no differences in body composition changes by mode of action with b/tsDMARDs.

Multicenter observational study on the efficacy of selective Janus Kinase-1 inhibitor upatacitinib in rheumatoid arthritis.

BACKGROUND: Upadacitinib (UPA) is a selective, reversible Janus kinase inhibitor (JAKi) approved for the treatment of RA. However, there is still no solid evidence on the long-term efficacy of UPA in treated patients. The purpose of this study was to determine the efficacy of UPA to obtain remission or low disease activity (LDA) in a series of UPA patients in patients with RA after 6 and 12 months of treatment in a real-world setting. METHODS: A series of 111 consecutive patients treated with UPA in 23 rheumatology centers were enrolled. Personal history, treatment history and disease activity at baseline, after 6 and 12 months were recorded. Intention-to-treat (ITT) and per-protocol (PP) analyses assessed achievement of remission or LDA or defined as DAS28 <2.6 and ≤3.2, respectively. Logistic regression analysis examined the role of several independent factors on the reduction of disease activity after 6 months of treatment. RESULTS: Of the initial group of 111 subjects at baseline, 86 and 29 participants completed clinical assessments at 6 and 12 months. According to ITT analysis, the rates of remission and LDA were 18% and 18% at 6 months and 31.5% and 12.5% at 12 months, respectively. PP analysis showed higher rates of remission and LDA at 6 (23.3% and 19.8%) and 12 months (55.2% and 20.7%). Results of multivariate logistic regression analysis indicated that a low DAS28 score (P=0.045) was the only predictor of achieving remission at 6 months. None of the baseline factors predicted remission/LDA at 6 months. CONCLUSIONS: RA patients treated with UPA achieved a significant rate of disease remission or LDA in a real-world setting. The 6-month response was found to depend only on the baseline value of DAS28, while it was not influenced by other factors such as disease duration, line of treatment or concomitant therapy with conventional synthetic disease-modifying antirheumatic drugs (csDMARDs) or corticosteroids.

Inhibition of CEACAM1 expression in cytokine-activated neutrophils using JAK inhibitors.

OBJECTIVES: Carcinoembryonic-antigen-related cell-adhesion molecule 1 (CEACAM1) is an adhesion molecule that acts as a coinhibitory receptor in the immune system. We previously demonstrated that CEACAM1 is predominantly expressed on peripheral blood neutrophils in patients with RA. The aim of the present study was to investigate the effects of Janus kinase inhibitors (JAKi) on cytokine-activated human neutrophils and CEACAM1 expression. METHODS: Peripheral blood neutrophils were obtained from healthy subjects. Isolated neutrophils were stimulated with tumor necrosis factor-alpha (TNF-α) or granulocyte-macrophage colony-stimulating factor (GM-CSF) in the presence or absence of JAKi. The expression of CEACAM1 in peripheral blood neutrophils was analyzed by flow cytometry. Protein phosphorylation of signal transducer and activator of transcription (STAT)1, STAT3, and STAT5 was assessed by western blot using phospho-specific antibodies. RESULTS: We found that TNF-α-induced CEACAM1 expression was marginally suppressed after pretreatment with pan-JAK inhibitor, tofacitinib. Moreover, TNF-α induced STAT1 and STAT3 phosphorylation at the late stimulation phase (4 to 16 h). The expressions of CEACAM1 on neutrophils were markedly up-regulated by GM-CSF not by interleukin (IL)-6 stimulation. All JAKi inhibited GM-CSF-induced CEACAM1 expressions on neutrophils, however, the inhibitory effects of baricitinib were larger compared to those of tofacitinib or filgotinib. Moreover, CEACAM1 was marginally upregulated in interferon (IFN)-γ stimulated neutrophils. Similarly, JAKi inhibited IFN-γ-induced CEACAM1 expressions on neutrophils. CONCLUSIONS: We demonstrated that JAKi prevent GM-CSF-induced CEACAM1 expression in neutrophils, and JAKi-induced inhibition depends on their selectivity against JAK isoforms. These findings suggest that JAKi can modulate the expression of CEACAM1 in cytokine-activated neutrophils, thereby limiting their activation.

Game changer: How Janus kinase inhibitors are reshaping the landscape of ulcerative colitis management.

Recent advancements in the treatment landscape of ulcerative colitis (UC) have ushered in a new era of possibilities, particularly with the introduction of Janus kinase (JAK)-signal transducer and activator of transcription inhibitors. These novel agents offer a paradigm shift in UC management by targeting key signaling pathways involved in inflammatory processes. With approved JAK inhibitors (JAKis), such as tofacitinib, filgotinib, and upadacitinib, clinicians now have powerful tools to modulate immune responses and gene expression, potentially revolutionizing the treatment algorithm for UC. Clinical trials have demonstrated the efficacy of JAKis in inducing and maintaining remission, presenting viable options for patients who have failed conventional therapies. Real-world data support the use of JAKis not only as first-line treatments but also in subsequent lines of therapy, particularly in patients with aggressive disease phenotypes or refractory to biologic agents. The rapid onset of action and potency of JAKis have broadened the possibilities in the management strategies of UC, offering timely relief for patients with active disease and facilitating personalized treatment approaches. Despite safety concerns, including cardiovascular risks and infections, ongoing research and post-marketing surveillance will continue to refine our understanding of the risk-benefit profile of JAKis in UC management.

Design and synthesis of triazolopyridine derivatives as potent JAK/HDAC dual inhibitors with broad-spectrum antiproliferative activity.

A series of triazolopyridine-based dual JAK/HDAC inhibitors were rationally designed and synthesised by merging different pharmacophores into one molecule. All triazolopyridine derivatives exhibited potent inhibitory activities against both targets and the best compound 4-(((5-(benzo[d][1, 3]dioxol-5-yl)-[1, 2, 4]triazolo[1, 5-a]pyridin-2-yl)amino)methyl)-N-hydroxybenzamide (19) was dug out. 19 was proved to be a pan-HDAC and JAK1/2 dual inhibitor and displayed high cytotoxicity against two cancer cell lines MDA-MB-231 and RPMI-8226 with IC50 values in submicromolar range. Docking simulation revealed that 19 fitted well into the active sites of HDAC and JAK proteins. Moreover, 19 exhibited better metabolic stability in vitro than SAHA. Our study demonstrated that compound 19 was a promising candidate for further preclinical studies.

Adverse Event Assessment of Upadacitinib: A Pharmacovigilance Study Based on the FAERS Database.

PURPOSE: Upadacitinib, a Janus kinase (JAK) inhibitor, has been approved by the FDA to treat various autoimmune conditions. This study assessed its adverse events by analyzing reports from the FDA Adverse Event Reporting System (FAERS). METHODS: FAERS data from Q3 2019 to Q4 2023 were extracted, and disproportionality analyses were conducted using four statistical measures, reporting odds ratio, proportionate reporting ratio, Bayesian confidence propagation neural network, and empirical Bayesian geometric mean. RESULTS: A total of 6 879 398 adverse event reports were collected, with 37 700 reports identifying upadacitinib as the "primary suspected." These reports involved 24 system organ classes and 246 preferred terms that met the criteria across all four algorithms. The distribution of adverse events was assessed separately for female and male patients. Further analysis of the top 25 preferred terms revealed that, although the system organ classes were similar between sexes, the specific adverse events differed. The adverse events were analyzed by gender, showing musculoskeletal and skin disorders were prevalent and severe in male patients, while musculoskeletal issues, infections, and abnormal laboratory tests were common in female patients. Unexpected events like trigger finger, biliary sepsis, and serious events such as oral neoplasm were also identified. CONCLUSION: This study provides real-world evidence for the safety evaluation of upadacitinib and underscores the need to monitor sex-specific adverse events. Future prospective studies are necessary to confirm these pharmacovigilance findings.

Real-world clinical efficacy of tofacitinib in moderate-to-severe ulcerative colitis.

Tofacitinib is an oral small-molecule Janus kinase (JAK) inhibitor that preferentially inhibits JAK1 and JAK3. Its efficacy in inducing and maintaining remission in ulcerative colitis (UC) as well as its safety profile has been demonstrated in multicenter, randomized, double-blind, placebo-controlled trials. Additionally, real-world studies evaluating the effectiveness and adverse effects of tofacitinib have been conducted, affirming its clinical efficacy in moderate-to-severe UC.

Normalized Interferon Signatures and Clinical Improvements by IFNAR1 Blocking Antibody (Anifrolumab) in Patients with Type I Interferonopathies.

PURPOSE: A causal role of type-I interferons (IFN-I) in autoinflammatory type-I interferonopathies such as SAVI (STING-associated vasculopathy with onset in infancy) and CANDLE (chronic atypical neutrophilic dermatosis with lipodystrophy and elevated temperatures) is suggested by elevated expression of IFN-I stimulated genes (ISGs). Hitherto, the lack of specific inhibitors of IFN-I signaling has prevented the verification of a causal role for IFN-I in these conditions. Commonly used inhibitors of the JAK/STAT pathway exert broad effects on multiple signaling pathways leading to more general immunosuppression beyond IFN-I signaling. METHODS: Here we show in four patients with SAVI and one patient with CANDLE syndrome that blockade of the IFNAR1 receptor (Anifrolumab) exerts an additive effect over JAK-inhibitor alone. In two patients with SAVI, monotherapy with Anifrolumab is sufficient to retain a suppressed IFN-I signature and clinical improvement. RESULTS: Anifrolumab normalizes IFN-I signature genes and relieves symptoms beyond what is typically achieved by a JAK-inhibitor (Baricitinib) alone in patients with type-I interferonopathies. In two patients Anifrolumab was used successfully as monotherapy. Addition of Anifrolumab enabled steroid tapering and cessation with reduced overall immunosuppression and lower risks of opportunistic infections and improved metabolic states and growth which is highly beneficial in these young patients. CONCLUSION: These results verify a causal role of IFN-I signaling in type-I Interferonopathies SAVI and CANDLE and suggests Anifrolumab as an important new treatment option in autoinflammatory diseases with elevated IFN-I induced gene expression. Genia Kretzschmar, Laura Piñero Páez, and Ziyang Tan are shared-first authors. Sara Alehashemi, AnnaCarin Horne, and Petter Brodin are co-senior author.

Tofacitinib for child-onset systemic lupus erythematosus.

Background: Systemic lupus erythematosus (SLE) is a chronic autoimmune disease that can cause diverse clinical manifestations in multiple organ systems. Child-onset SLE (cSLE) is associated with significantly higher morbidity and mortality than adult-onset SLE. The traditional treatments for SLE (glucocorticoids, antimalarials, conventional and biological disease-modifying antirheumatic drugs) often have significant adverse effects and may not fully control disease activity. Tofacitinib is an oral Janus kinase (JAK) inhibitor that inhibits the JAK-STAT pathway and has the potential to reduce SLE severity. Methods: cSLE patients who received tofacitinib and had at least one follow-up visit were retrospectively examined. Case histories, laboratory test results, and treatment regimens were analyzed at disease onset, initiation of tofacitinib treatment, and 1, 3, 6, 9, 12, 18, and 24 months after starting tofacitinib. Results: We examined 9 patients with refractory cSLE. All patients were female and the average age at diagnosis was 10.67 years. At initiation of tofacitinib, the average age was 13.28 years and the average disease duration was 2.62 years. Four patients experienced alleviation of symptoms and reduced their daily prednisone dosages; one of them also discontinued cyclosporine A and two of them also discontinued belimumab. The other 5 patients experienced no apparent benefit. Conclusion: Tofacitinib may provide clinical benefits for some patients with refractory cSLE, and can also allow reduction in the glucocorticoid dosage. Tofacitinib has the potential as an adjunctive treatment for some patients with cSLE.

Th1 and Th2 cytokine expression in hyperkeratotic chronic hand eczema and the role of Tofacitinib a oral JAK inhibitor.

Tissue cytokines in chronic hand eczema (CHE) can predict targeted therapy with novel drugs including JAK inhibitors. Our primary objective was to assess the tissue expression of cytokines of Th1 and Th2 cell lines in CHE patients and to study the efficacy of oral tofacitinib. We recruited patients presenting with recalcitrant CHE. Lesional and non-lesional tissue samples were assessed for Th1(IFN-γ, TNF-α) and Th2 related cytokines (IL-4, IL-13, IL-2,) using real time PCR. Tofacitinib 5 mg twice daily was initiated with 4 weekly assessment and we also noted relapses post therapy.Of 21 refractory hyperkeratotic CHE patients, cytokine analysis was performed in 11 patients which showed upregulation of IL-4 [n = 5/11, 1.87-fold increase], TNF-α (n = 5/11, 5.13-fold) and IFN-γ (n = 6/11, 1.98-fold) as compared to uninvolved skin. All patients (100%) had used topical corticosteroids (TCS) and 4/21 (19%) had failed methotrexate and 2/21 (9.5%) had failed acitretin. Tofacitinib 5 mg twice daily was given in 15/21 patients. The mean time to achieve hand eczema severity index 90 (HECSI 90) was 4 weeks (mean duration of treatment:5.8 months, n = 12). Side effects were observed in 4/12 (33.3%) patients and relapse was noted in 3/12 (25%) patients after a mean duration of 7 months after discontinuation of tofacitinib. Tofacitinib (pan-JAK inhibitor) showed an excellent response in refractory CHE patients with predominant tissue Th1/Th2 cells related cytokine expression.

The ABCs of JAKis: A Clinician's Guide to Safety and Monitoring of the Systemic JAK Inhibitors.

Janus kinase inhibitors (JAKis) have recently emerged in the arsenal of tools to treat dermatological conditions. However, there are some concerns regarding these treatments due to their boxed warning. Here we discuss the safe and effective use of JAKs for the treatment of a wide variety of dermatologic conditions. We will also discuss monitoring guidelines. J Drugs Dermatol. 2024;23(10):852-856. doi:10.36849/JDD.8073.

Review article: Novel therapies in inflammatory bowel disease - An update for clinicians.

BACKGROUND: Several new treatments including small molecules and biologics have been approved for the treatment of inflammatory bowel diseases in recent years. Clinicians and patients now have a wide variety of therapeutic options to choose from and these novel therapies provide several advantages including oral administration, lower immunogenicity, better selectivity and arguably better safety profiles. An increase in treatment options has increased the complexity of decision-making. Both patients and clinicians have had to become rapidly familiar with efficacy of new medications balanced against a range of pre-initiation requirements, dosing schedules and adverse event profiles. AIMS: To provide a simple guide to practising clinicians on recently approved and emerging therapies and address key challenges around treatment strategies such as optimal sequencing and timing of treatment. METHODS: We comprehensively searched the published literature and major conference abstracts to identify phase III placebo-controlled and active comparator trials for Crohn's disease and ulcerative colitis. RESULTS: Data for recently approved therapies including selective Janus kinase inhibitors, sphingosine-1 receptor modulators and p19 interleukin (IL)-23 inhibitors have demonstrated improved patient outcomes in both Crohn's disease and ulcerative colitis. Further comparative head-to-head studies have improved our understanding of when and how to optimally use newer therapies, specifically for IL-23 inhibitors. Data for emerging treatment options and novel treatment strategies such as early effective treatment, combinations of treatments and implications for sequencing are continuing to transform IBD care continually. CONCLUSIONS: Recently approved novel therapies have expanded the range of medical options available to treat IBD. However, further data from long-term extension studies, real-world studies and head-to-head trials are warranted to better inform the long-term safety and optimal sequencing of treatments for patients living with IBD.

JAK inhibitors to treat STAT3 gain-of-function: a single-center report and literature review.

Objective: The signal transducer and activator of transcription 3 (STAT3) gain-of-function (GOF) syndrome (STAT3-GOF) is an inborn error of immunity (IEI) characterized by diverse manifestations of immune dysregulation that necessitate systemic immunomodulatory treatment. The blockade of the interleukin-6 receptor and/or the inhibition of the Janus kinases has been commonly employed to treat diverse STAT3-GOF-associated manifestations. However, evidence on long-term treatment outcome, especially in the case of adult patients, is scarce. Methods: Clinical data, including laboratory findings and medical imaging, were collected from all seven patients, diagnosed with STAT3-GOF, who have been treated at the Hannover University School, focusing on those who received a Janus kinase (JAK) inhibitor (JAKi). Previously published cases of STAT3-GOF patients who received a JAKi were evaluated, focusing on reported treatment efficacy with respect to diverse STAT3-GOF-associated manifestations of immune dysregulation and safety. Results: Five out of seven patients diagnosed with STAT3-GOF were treated with a JAKi, each for a different indication. Including these patients, outcomes of JAKi treatment have been reported for a total of 41 patients. Treatment with a JAKi led to improvement of diverse autoimmune, inflammatory, or lymphoproliferative manifestations of STAT3-GOF and a therapeutic benefit could be documented for all except two patients. Considering all reported manifestations of immune dysregulation in each patient, complete remission was achieved in 10/41 (24.4%) treated patients. Conclusions: JAKi treatment improved diverse manifestations of immune dysregulation in the majority of STAT3-GOF patients, representing a promising therapeutic approach. Long-term follow-up data are needed to evaluate possible risks of prolonged treatment with a JAKi.

Navigating therapeutic challenges in VEXAS syndrome: exploring IL-6 and JAK inhibitors at the forefront.

VEXAS syndrome, an uncommon yet severe autoimmune disorder stemming from a mutation in the UBA1 gene, is the focus of this paper. The overview encompasses its discovery, epidemiological traits, genetic underpinnings, and clinical presentations. Delving into whether distinct genotypes yield varied clinical phenotypes in VEXAS patients, and the consequent adjustment of treatment strategies based on genotypic and clinical profiles necessitates thorough exploration within the clinical realm. Additionally, the current therapeutic landscape and future outlook are examined, with particular attention to the potential therapeutic roles of IL-6 inhibitors and JAK inhibitors, alongside an elucidation of prevailing limitations and avenues for further research. This study contributes essential theoretical groundwork and clinical insights for both diagnosing and managing VEXAS syndrome.