Risks and Benefits of Janus Kinase Inhibitors in Rheumatoid Arthritis - Past, Present, and Future

Rheumatoid arthritis extra-articular lung disease: new insights on pathogenesis and experimental drugs

INTRODUCTION

Pulmonary involvement is one of the most common extra-articular manifestations of rheumatoid arthritis (RA), a systemic inflammatory disease characterized by joint swelling and tenderness. All lung compartments can be interested in the course of RA, including parenchyma, airways, and, more rarely, pleura and vasculature.

AREAS COVERED

The aim of this paper is to review the main RA lung manifestations, focusing on pathogenesis, clinical and therapeutic issues of RA-related interstitial lung disease (ILD). Despite an increasing number of studies in the last years, pathogenesis of RA-ILD remains largely debated and the treatment of RA patients with lung involvement is still challenging in these patients.

EXPERT OPINION

Management of RA-ILD is largely based on expert-opinion. Due to the broad clinical manifestations, including both joints and pulmonary involvement, multidisciplinary discussion, including rheumatologist and pulmonologist, is essential, not only for diagnosis, but also to evaluate the best therapeutic approach and follow-up. In fact, the coexistence of different lung manifestations may influence the treatment response and safety. The identification of biomarkers and risk-factors for an early identification of RA patients at risk of developing ILD remains a need that still needs to be fulfilled, and that will require further investigation in the next years.

Increased risk of cardiovascular events under the treatments with Janus kinase inhibitors versus biological disease-modifying antirheumatic drugs in patients with rheumatoid arthritis: a retrospective longitudinal population-based study using the Japanese health insurance database

OBJECTIVES

To compare the risk of cardiovascular events among Janus kinase inhibitors (JAKIs), biological disease-modifying antirheumatic drugs (bDMARDs) (tumour necrosis factor inhibitors (TNFIs) and non-TNFIs) and methotrexate (MTX) in Japanese patients with rheumatoid arthritis (RA).

METHODS

Using Japanese claims data, patients with RA were enrolled in this study if they had at least one ICD-10 code (M05 or M06), were new users of JAKIs, bDMARDs or MTX between July 2013 and July 2020 and being 18 years old or older. The incidence rate (IR), IR ratio and adjusted hazard ratio (aHR (95% CI)) of cardiovascular events including venous thromboembolism, arterial thrombosis, acute myocardial infarction and stroke were calculated. A time-dependent Cox regression model adjusted for patient characteristics at baseline was used to calculate aHR.

RESULTS

In 53 448 cases, IRs/1000 patient-years of the overall cardiovascular events were 10.1, 6.8, 5.4, 9.1 and 11.3 under the treatments with JAKIs, bDMARDs, TNFIs, non-TNFIs and MTX, respectively. The adjusted HRs of JAKIs for overall cardiovascular events were 1.7 (1.1 to 2.5) versus TNFIs without MTX and 1.7 (1.1 to 2.7) versus TNFIs with MTX.

CONCLUSIONS

Among patients with RA, individuals using JAKIs had a significantly higher risk of overall cardiovascular events than TNFIs users, which was attributed to the difference in the risk between JAKIs and TNFIs versus MTX. These data should be interpreted with caution because of the limitations associated with the claims database.

Individuals with JAK1 variants are affected by syndromic features encompassing autoimmunity, atopy, colitis, and dermatitis

Inborn errors of immunity lead to autoimmunity, inflammation, allergy, infection, and/or malignancy. Disease-causing JAK1 gain-of-function (GoF) mutations are considered exceedingly rare and have been identified in only four families. Here, we use forward and reverse genetics to identify 59 individuals harboring one of four heterozygous JAK1 variants. In vitro and ex vivo analysis of these variants revealed hyperactive baseline and cytokine-induced STAT phosphorylation and interferon-stimulated gene (ISG) levels compared with wild-type JAK1. A systematic review of electronic health records from the BioME Biobank revealed increased likelihood of clinical presentation with autoimmunity, atopy, colitis, and/or dermatitis in JAK1 variant-positive individuals. Finally, treatment of one affected patient with severe atopic dermatitis using the JAK1/JAK2-selective inhibitor, baricitinib, resulted in clinically significant improvement. These findings suggest that individually rare JAK1 GoF variants may underlie an emerging syndrome with more common presentations of autoimmune and inflammatory disease (JAACD syndrome). More broadly, individuals who present with such conditions may benefit from genetic testing for the presence of JAK1 GoF variants.

Non-Invasive Assessment of Micro- and Macrovascular Function after Initiation of JAK Inhibitors in Patients with Rheumatoid Arthritis

BACKGROUND

Janus kinase (JAK) inhibitors constitute a novel class of oral biologic disease-modifying antirheumatic drugs for patients with rheumatoid arthritis (RA). However, their use has been associated with increased risk of major cardiovascular events. We investigated whether treatment with JAK inhibitors exerts significant alterations in the micro- and microvasculature in RA patients.

METHODS

Thirteen patients with RA initiating treatment with JAK inhibitors were prospectively studied. Eventually, data from 11 patients who completed the study were analyzed. Procedures were performed at baseline and 3 months after treatment. Nailfold videocapillaroscopy was applied to detect alterations of the dermal capillary network. Participants underwent 24 h ambulatory blood pressure monitoring (Mobil-O-Graph device) for the assessment of blood pressure (both brachial and aortic) and markers of large artery stiffening [pulse wave velocity (PWV), augmentation index] throughout the whole 24 h and the respective day- and nighttime periods. Carotid intima-media thickness was assessed with ultrasound.

RESULTS

Three-month treatment with JAK inhibitors was not associated with any differences in brachial and aortic blood pressure, arterial stiffness, and carotid atherosclerosis, with the only exception of nighttime PWV, which was significantly elevated at follow-up. However, three-month treatment with JAK inhibitors induced significant microvascular alterations and increased the total number of capillaroscopic abnormalities.

CONCLUSIONS

Three-month treatment with JAK inhibitors may exert significant effects on microcirculation as assessed with nailfold videocapillaroscopy, whereas macrovascular structure and function appears largely unaffected. Further research toward this direction may add substantial information to the available literature regarding cardiovascular aspects of JAK inhibitors in RA.

JAK-Inhibitors - A Story of Success and Adverse Events

Rheumatoid arthritis (RA) is a systemic, chronic, immune-mediated inflammatory condition. Treatments options encompass conventional synthetic disease-modifying antirheumatic drugs (csDMARDs), biologic disease-modifying antirheumatic drugs (bDMARDs) like tumor necrosis factor (TNF) inhibitors (TNFis) and targeted synthetic disease-modifying antirheumatic drugs (tsDMARDs) including Janus Kinase inhibitors (JAKinibs). Orally administered JAKinibs have demonstrated comparable or, in specific cases, superior efficacy compared to bDMARDs in inflammatory conditions. However, the escalating clinical utilization has been accompanied by the emergence of serious adverse effects, including major adverse cardiac events (MACE), malignancies and venous thrombotic episodes (VTE), leading to regulatory restrictions imposed by health authorities in both the US Food and Drug Administration (FDA) and the European Medicines Agency (EMA).

Efficacy and safety of JAK inhibitors in rheumatoid arthritis: update for the practising clinician

Janus kinase (JAK) inhibitors, including tofacitinib, baricitinib, upadacitinib and filgotinib, are increasingly used in the treatment of rheumatoid arthritis (RA). There has been debate about their safety, particularly following the issuance of guidance by regulatory agencies advising caution in their use in certain patients. The registrational clinical trials and registry data of JAK inhibitors did not identify a difference in the risk of major adverse cardiovascular events (MACEs), venous thromboembolism, malignancies or infections (other than herpes zoster) with a JAK inhibitor versus a biologic DMARD. In the ORAL Surveillance trial, which enrolled patients >50 years of age with ≥1 cardiovascular risk factor, tofacitinib was statistically inferior to TNF inhibitors for the occurrence of MACEs and malignancy. Further post hoc analysis of the data revealed that an age of ≥65 years, a high baseline cardiovascular risk, a history of smoking, sustained inflammation, disease activity and suboptimal treatment of cardiovascular comorbidities all increase the risk of these outcomes. The guidance issued by regulatory agencies should be carefully considered to ensure appropriate and safe treatment of patients with RA without undertreatment of patients who might benefit from JAK inhibitor, as well as biologic, treatment. As always, the risks associated with the use of these agents, treatment goals, costs and patient preferences should be discussed with the patient.

Cardiovascular risk of Janus kinase inhibitors compared with biologic disease-modifying antirheumatic drugs in patients with rheumatoid arthritis without underlying cardiovascular diseases: a nationwide cohort study

Objectives: Despite the ethnic differences in cardiovascular (CV) risks and recent increase in the prescription of Janus kinase (JAK) inhibitors, limited evidence is available for their CV outcomes in Asian patients with rheumatoid arthritis (RA). We aimed to compare the major adverse CV events (MACEs) of JAK inhibitors to those of biologic disease-modifying antirheumatic drugs (bDMARDs) in Korean patients with RA without baseline CV disease (CVD). Methods: In a nationwide retrospective cohort study, patients newly diagnosed with RA without a history of CVD between 2013 and 2018 were identified using the National Health Insurance Service database. The cohort was followed up until the end of 2019 for the development of MACEs. Hazard ratios (HRs) for MACEs such as myocardial infarction, stroke, coronary revascularization, or all-cause death, were estimated using Cox proportional hazard regression in a propensity score-matched cohort. Results: In total, 4,230 matched patients with RA were included (846 JAK inhibitor users and 3,384 bDMARD users). The crude incidence rate (95% confidence intervals, CI) per 100 patient-years for MACEs was 0.83 (0.31-1.81) and 0.74 (0.53-1.02) in the JAK inhibitor and bDMARD groups, respectively. The risk of MACEs was not significantly different between JAK inhibitor and bDMARD users with an adjusted HR (95% CI) of 1.28 (0.53-3.11). There were no significant differences in the risk of MACEs between JAK inhibitors and bDMARDs in each subgroup according to the types of bDMARDs, age, sex, Charlson comorbidity index score, and comorbidities. Conclusion: Compared to bDMARDs, JAK inhibitors were not associated with the occurrence of MACEs in Korean patients with RA without a history of CVD.

Janus Kinase Inhibitors in Rheumatoid Arthritis: An Update on the Efficacy and Safety of Tofacitinib, Baricitinib and Upadacitinib

Janus kinase inhibitors (JAKis) are the most recent new drug class to arrive to the market for rheumatoid arthritis (RA) treatment. While they have proven to be a very effective treatment option, there remains significant concern regarding the risk of cardiovascular events, thrombosis and malignancy, particularly given the findings of the post-marketing ORAL Surveillance study and FDA black box warnings. This article reviews the key findings of the most impactful cohort of studies and registry data since ORAL Surveillance. It also evaluates the role of JAKis in practice and offers guidance on risk stratifying patients and determining their suitability for a JAKi.

Cardiovascular risk in axial spondyloarthritis-a systematic review

Cardiovascular manifestations are common in patients suffering axial spondyloarthritis and can result in substantial morbidity and disease burden. To give an overview of this important aspect of axial spondyloarthritis, we conducted a systematic literature search of all articles published between January 2000 and 25 May 2023 on cardiovascular manifestations. Using PubMed and SCOPUS, 123 out of 6792 articles were identified and included in this review. Non-radiographic axial spondyloarthritis seems to be underrepresented in studies; thus, more evidence for ankylosing spondylitis exists. All in all, we found some traditional risk factors that led to higher cardiovascular disease burden or major cardiovascular events. These specific risk factors seem to be more aggressive in patients with spondyloarthropathies and have a strong connection to high or long-standing disease activity. Since disease activity is a major driver of morbidity, diagnostic, therapeutic, and lifestyle interventions are crucial for better outcomes. Key Points • Several studies on axial spondyloarthritis and associated cardiovascular diseases have been conducted in the last few years addressing risk stratification of these patients including artificial intelligence. • Recent data suggest distinct manifestations of cardiovascular disease entities among men and women which the treating physician needs to be aware of. • Rheumatologists need to screen axial spondyloarthritis patients for emerging cardiovascular disease and should aim at reducing traditional risk factors like hyperlipidemia, hypertension, and smoking as well as disease activity.

JAK-STAT inhibition reduces endothelial prothrombotic activation and leukocyte-endothelial proadhesive interactions

BACKGROUND

Vascular activation is characterized by increased proinflammatory, pro thrombotic, and proadhesive signaling. Several chronic and acute conditions, including Bcr-abl-negative myeloproliferative neoplasms (MPNs), graft-vs-host disease, and COVID-19 have been noted to have increased activation of the janus kinase (JAK)-signal transducer and downstream activator of transcription (STAT) pathways. Two notable inhibitors of the JAK-STAT pathway are ruxolitinib (JAK1/2 inhibitor) and fedratinib (JAK2 inhibitor), which are currently used to treat MPN patients. However, in some conditions, it has been noted that JAK inhibitors can increase the risk of thromboembolic complications.

OBJECTIVES

We sought to define the anti-inflammatory and antithrombotic effects of JAK-STAT inhibitors in vascular endothelial cells.

METHODS

We assessed endothelial activation in the presence or absence of ruxolitinib or fedratinib by using immunoblots, immunofluorescence, qRT-PCR, and function coagulation assays. Finally, we used endothelialized microfluidics perfused with blood from normal and JAK2V617F+ individuals to evaluate whether ruxolitinib and fedratinib changed cell adhesion.

RESULTS

We found that both ruxolitinib and fedratinib reduced endothelial cell phospho-STAT1 and STAT3 signaling and attenuated nuclear phospho-NK-κB and phospho-c-Jun localization. JAK-STAT inhibition also limited secretion of proadhesive and procoagulant P-selectin and von Willebrand factor and proinflammatory IL-6. Likewise, we found that JAK-STAT inhibition reduced endothelial tissue factor and urokinase plasminogen activator expression and activity.

CONCLUSIONS

By using endothelialized microfluidics perfused with whole blood samples, we demonstrated that endothelial treatment with JAK-STAT inhibitors prevented rolling of both healthy control and JAK2V617F MPN leukocytes. Together, these findings demonstrate that JAK-STAT inhibitors reduce the upregulation of critical prothrombotic pathways and prevent increased leukocyte-endothelial adhesion.

Venous Thromboembolism in the Inflammatory Rheumatic Diseases

Venous thromboembolism (VTE), which includes deep venous thrombosis and pulmonary embolism, is a cardiovascular event whose risk is increased in most inflammatory rheumatic diseases (IRDs). Mechanisms that increase VTE risk include antiphospholipid antibodies (APLs), particularly anticardiolipin antibodies, anti-beta2glycoprotein I antibodies and lupus anticoagulant present together, and inflammation-mediated endothelial injury. Patients with IRDs should receive long-term anticoagulation drugs when the risk of VTE recurrence is high. In the light of recent warnings from regulatory agencies regarding heightened VTE risk with Janus kinase inhibitors, these drugs should be initiated only after a careful assessment of VTE risk in those with IRDs.

Effects of inhaled JAK inhibitor GDC-4379 on exhaled nitric oxide and peripheral biomarkers of inflammation

BACKGROUND

Janus Kinases (JAKs) mediate activity of many asthma-relevant cytokines. GDC-0214, an inhaled small molecule JAK1 inhibitor, has previously been shown to reduce fractional exhaled nitric oxide (FeNO) in patients with mild asthma, but required an excessive number of inhalations.

AIM

To assess whether GDC-4379, a new inhaled JAK inhibitor, reduces FeNO and peripheral biomarkers of inflammation.

METHODS

This study assessed the activity of GDC-4379 in a double-blind, randomized, placebo-controlled, Phase 1 study in patients with mild asthma. Participants included adults (18-65y) with a diagnosis of asthma for ≥6 months, forced expiratory volume in 1 s (FEV₁)> 70% predicted, FeNO >40 ppb, using as-needed short-acting beta-agonist medication only. Four sequential, 14-day, ascending-dose cohorts (10 mg QD, 30 mg QD, 40 mg BID, and 80 mg QD) of 12 participants each were randomized 2:1 to GDC-4379 or placebo. The primary activity outcome was percent change from baseline (CFB) in FeNO to Day 14 compared to the pooled placebo group. Safety, tolerability, pharmacokinetics, and pharmacodynamic biomarkers, including blood eosinophils, serum CCL17, and serum CCL18, were also assessed.

RESULTS

Of 48 enrolled participants, the mean age was 25 years and 54% were female. Median (range) FeNO at baseline was 79 (41-222) ppb. GDC-4379 treatment led to dose-dependent reductions in FeNO. Compared to placebo, mean (95% CI) percent CFB in FeNO to Day 14 was: -6 (-43, 32) at 10 mg QD, -26 (-53, 2) at 30 mg QD, -55 (-78, -32) at 40 mg BID and -52 (-72, -32) at 80 mg QD. Dose-dependent reductions in blood eosinophils and serum CCL17 were also observed. Higher plasma drug concentrations corresponded with greater FeNO reductions. No serious AEs occurred. The majority of AEs were mild to moderate. The most common AEs were headache and oropharyngeal pain. Minor changes in neutrophils were noted at 80 mg QD, but were not considered clinically meaningful.

CONCLUSIONS

In patients with mild asthma, 14-day treatment with GDC-4379 reduced FeNO levels and peripheral biomarkers of inflammation. Treatment was well tolerated without any major safety concerns.

AUSTRALIAN NEW ZEALAND CLINICAL TRIALS REGISTRY

ACTRN12619000227190.