JAK/STAT Inhibition Normalizes Lipid Composition in 3D Human Epidermal Equivalents Challenged with Th2 Cytokines.

Derangement of the epidermal barrier lipids and dysregulated immune responses are key pathogenic features of atopic dermatitis (AD). The Th2-type cytokines interleukin IL-4 and IL-13 play a prominent role in AD by activating the Janus Kinase/Signal Transduction and Activator of Transcription (JAK/STAT) intracellular signaling axis. This study aimed to investigate the role of JAK/STAT in the lipid perturbations induced by Th2 signaling in 3D epidermal equivalents. Tofacitinib, a low-molecular-mass JAK inhibitor, was used to screen for JAK/STAT-mediated deregulation of lipid metabolism. Th2 cytokines decreased the expression of elongases 1, 3, and 4 and serine-palmitoyl-transferase and increased that of sphingolipid delta(4)-desaturase and carbonic anhydrase 2. Th2 cytokines inhibited the synthesis of palmitoleic acid and caused depletion of triglycerides, in association with altered phosphatidylcholine profiles and fatty acid (FA) metabolism. Overall, the ceramide profiles were minimally affected. Except for most sphingolipids and very-long-chain FAs, the effects of Th2 on lipid pathways were reversed by co-treatment with tofacitinib. An increase in the mRNA levels of CPT1A and ACAT1, reduced by tofacitinib, suggests that Th2 cytokines promote FA beta-oxidation. In conclusion, pharmacological inhibition of JAK/STAT activation prevents the lipid disruption caused by the halted homeostasis of FA metabolism.

Safety of Janus kinase inhibitors compared to biological DMARDs in patients with rheumatoid arthritis and renal impairment: the ANSWER cohort study.

Data on the safety of Janus kinase inhibitors (JAKis) in patients with renal impairment are lacking. This study aimed to investigate the safety of JAKis compared to biological (b) DMARDs in patients with rheumatoid arthritis (RA) and renal impairment. We used a multi-centre observational registry of patients with RA in Japan (the ANSWER cohort). We assessed the drug retention rates of b/targeted synthetic DMARDs with different modes of action (tumour necrosis factor inhibitors (TNFis), immunoglobulins fused with cytotoxic T-lymphocyte antigen (CTLA-4-Ig), interleukin-6 receptor inhibitors (IL-6Ris), and JAKis) in patients with RA stratified by pre-treatment estimated glomerular filtration rate (eGFR) levels. The time to discontinuation of bDMARDs or JAKis was analysed using a multivariate Cox proportional hazards model This study included 3775 patients, who were classified into three groups (the normal group (eGFR ≥ 60 mL/min/1.73 m2): 2893 patients; CKDa group (eGFR 45-60 mL/min/1.73 m2): 551; and CKDb group (eGFR < 45 mL/min/1.73 m2): 331). In the CKDb group, the 12-month drug retention rate due to adverse events (AE) was the lowest in patients treated with JAKi (TNFi: 93.1%; IL-6Ri: 94.1%; CTLA-4-Ig: 92.3%; JAKi: 75.1%). In the normal and CKDa groups, drug retention rates due to AE were similar among patients treated with bDMARDs and JAKi. In contrast, drug retention rates due to inefficacy were similar between bDMARDs and JAKis in all groups. In the Cox-proportional model, in the CKDb group, TNFi, IL-6Ri, and CTLA-4-Ig showed lower incidence of drug discontinuation due to AE than JAKis (TNFi: hazard ratio = 0.23 (95% confidence interval 0.09-0.61), IL-6Ri: 0.34 (0.14-0.81), CTLA-4-Ig: 0.36 (0.15-0.89)). JAKis showed the lowest drug retention due to AE in patients with moderate-to-severe and severe renal impairment (eGFR < 45 mL/min/1.73 m2). Physicians should pay more attention to renal function when using JAKis than when using bDMARDs.

Inhibition of the JAK-STAT Pathway in the Treatment of Psoriasis: A Review of the Literature.

Psoriasis is a highly prevalent dermatological disease associated with an increased systemic inflammatory response. In addition, joint involvement is also present in around 20% of patients. Therefore, treatment modalities used in this condition should be simultaneously effective at improving skin manifestations, reducing inflammation, and addressing psoriatic arthritis when present. Twenty years ago, the introduction of biologic treatments for psoriasis was a turning point in the management of this condition, offering an effective and reasonably safe option for patients whose disease could not be adequately controlled with conventional therapies. At the moment, Janus Kinase inhibitors (JAKis) are a new class of promising molecules in the management of psoriasis. They are orally administered and can show benefits in patients who failed biologic therapy. We conducted a scoping review in order to identify randomized-controlled trials that investigated different JAKis in patients with plaque psoriasis and psoriatic arthritis, with an emphasis on molecules that have been approved by the European Medicines Agency and the Food and Drug Administration. The added value of this study is that it collected information about JAKis approved for two different indications, plaque psoriasis and psoriatic arthritis, in order to provide an integrated understanding of the range of effects that JAKis have on the whole spectrum of psoriasis manifestations.

Oral Prescription Management.

The treatment of atopic dermatitis (AD) with oral treatments has been limited in the past due to the increased risk of adverse effects associated with oral agents. However, in recent years, a shift toward the minimization of adverse effects has been explored. Although existing treatment options like oral corticosteroids and Immunosuppressive therapies have been utilized for acute flare-ups of AD, their long-term use is limited by adverse effects and the need for lab monitoring. New systemic treatment options such as Janus kinase (JAK) inhibitors are emerging as a promising therapy, due to their quick onset and antipruritic features. However, the black box warning associated with this medication class requires careful selection of appropriate candidates and patient education despite early favorable safety profiles seen in AD trials. Discussion of other oral agents, like antibiotics and antihistamines, and their role in AD management are also clarified.

The Future of Atopic Dermatitis Treatment.

This chapter thoroughly examines recent breakthroughs in atopic dermatitis (AD) treatment, with a primary focus on the medications in the development pipeline. Biologics agents targeting new interleukin receptors like interleukin-31, interleukin-22, and interleukin-2 are discussed along with the novel pathway looking at the OX40-OX40L interaction. Oral agents and small molecule therapies like Janus kinase inhibitors, sphingosine-1-phosphate modulators, and Bruton's tyrosine kinase inhibitors are also discussed along with the various new topical medications. Newly approved topicals like phosphodiesterase-4 and JAK inhibitors are highlighted while also discussing the potential of tapinarof and emerging microbiome-targeted therapies. Beyond conventional approaches, the chapter touches upon unconventional therapies currently being studied. The goal of this chapter is to discuss new advances in AD treatment from medications in the initial stages of development to those nearing FDA approval.

Total eosinophil count as a biomarker for therapeutic effects of upadacitinib in atopic dermatitis over 48 weeks.

Background: Atopic dermatitis (AD) is a chronic skin disease characterized by type 2-skewed immune responses, and significantly influenced by cytokines dependent on Janus kinases (JAKs). Upadacitinib, a JAK1 inhibitor, is effective for moderate-to-severe AD. This study aims to identify biomarkers that reflect long-term therapeutic effects of upadacitinib 15 mg or 30 mg. Methods: A retrospective study from August 2021 to July 2023 included 213 AD patients treated with upadacitinib 15 mg and 70 AD patients with 30 mg. We analyzed eczema area and severity index (EASI), peak pruritus-numerical rating scale (PP-NRS), serum immunoglobulin E (IgE), thymus and activation-regulated chemokine (TARC), lactate dehydrogenase (LDH), and total eosinophil count (TEC) at weeks 0, 4, 12, 24, 36, and 48 of treatment. Results: Both treatments with upadacitinib 15 mg and 30 mg significantly reduced EASI and PP-NRS scores over week 4 to 48 compared to baseline. Upadacitinib 15 mg or 30 mg treatment significantly decreased TEC compared to baseline through week 4 to 36 or week 4 to 48, respectively. The percent reduction of TEC correlated with those of EASI and PP-NRS through week 4 to 48 of treatment with upadacitinib 15 mg, or through week 12 to 48 with 30 mg, respectively. After adjusting for % reductions of other laboratory markers, the significance of correlations was preserved at weeks 36 and 48 of 15 mg treatment, while at weeks 4 and 36 of 30 mg treatment. Conclusion: The % reduction of TEC correlated with those of EASI and PP-NRS during upadacitinib treatment, indicating its potential as a biomarker reflecting treatment responses to upadacitinib in AD patients. However, the variability of significant correlation during treatment indicates that further inspection is needed for its usefulness in monitoring responses to upadacitinib treatment for AD.

Novel insights into the management of rheumatoid arthritis: one year in review 2024.

New evidence from 2023 has slightly shifted some perspectives on rheumatoid arthritis (RA) management. Glucocorticoids have reaffirmed their role as bridging therapy, while novel studies on JAK inhibitors have examined efficacy, mechanism of action, and their potential in high-risk populations, bolstering our understanding with real-world data.Additionally, among treatment strategies, achieving low disease activity has emerged as comparable to achieving remission in the long term, and new insights have been gained regarding tapering both biological and conventional synthetic DMARDs. Furthermore, novel approaches have been proposed for managing difficult-to-treat RA and pre-RA. In this paper, the reviewers aim to present the most relevant studies published during the last year in the field of RA management.

RuBi-Ruxolitinib: A Photoreleasable Antitumor JAK Inhibitor.

We describe the synthesis and biological testing of ruthenium-bipyridine ruxolitinib (RuBiRuxo), a photoreleasable form of ruxolitinib, a JAK inhibitor used as an antitumoral agent in cutaneous T-cell lymphomas (CTCL). This novel caged compound is synthesized efficiently, is stable in aqueous solution at room temperature, and is photoreleased rapidly by visible light. Irradiation of RuBiRuxo reduces cell proliferation and induces apoptosis in a light- and time-dependent manner in a CTCL cell line. This effect is specific and is mediated by a decreased phosphorylation of STAT proteins. Our results demonstrate the potential of ruthenium-based photocompounds and light-based therapeutic approaches for the potential treatment of cutaneous lymphomas and other pathologies.

Targeted Combined Endpoint Improvement in Patient and Disease Domains in Atopic Dermatitis: A Treat-to-Target Analysis of Adults with Moderate-to-Severe Atopic Dermatitis Treated with Upadacitinib.

A treat-to-target approach was recently developed to guide systemic treatment for adults with atopic dermatitis (AD). Recommendations outlined criteria for a 3-month initial acceptable treatment target and a 6-month optimal target, evaluated using global assessment of patient-reported disease severity, as well as Eczema Area and Severity Index, itch assessed on an 11-point numerical rating scale, Dermatology Life Quality Index, or Patient-Oriented Eczema Measure. Achievement of these targets with once-daily upadacitinib (15 mg and 30 mg) monotherapy was evaluated using integrated adult data from the Measure Up 1 and 2 phase 3 studies. Among the 852 patients treated with upadacitinib 15 mg or 30 mg, the 3-month initial acceptable target was achieved by >80%, >78%, and ≥87% of patients, and the 6-month optimal target was achieved by ≥53%, >61%, and >73% of patients at weeks 2, 16, and 52, respectively. Achievement of all 6 individual criteria for each of the target goals also increased over time. These findings suggest that upadacitinib 15 mg and 30 mg may help improve standards of care in patients with moderate-to-severe AD by achieving 6-month target goals at 16 weeks and as early as 2 weeks for most patients.

Ruxolitinib 1.5% Topical Cream for the Treatment of Pediatric Alopecia Areata.

Alopecia areata (AA) is a common autoimmune disorder. Although its pathogenesis is not fully understood, AA involves CD8 T cell-mediated destruction of the hair follicle. Several treatment options exist; however, there is minimal evidence in the pediatric population. Currently, there are no curative treatments for AA. The literature suggests that Janus kinase (JAK) inhibitors may be an effective treat-ment for AA, but evidence in pediatric patients is limited. Here, we report a case of severe pediatric AA treated with topical ruxolitinib, a JAK inhibitor. J Drugs Dermatol. 2024;23(5):378-379. doi:10.36849/JDD.7782.

JAK2 inhibitors improve RA combined with pulmonary fibrosis in rats by downregulating SMAD3 phosphorylation.

BACKGROUND: JAK inhibitors are well known for the treatment of rheumatoid arthritis (RA), but whether they can be used to treat pulmonary fibrosis, a common extra-articular disease of RA, remains to be clarified. METHODS: A jak2 inhibitor, CEP33779 (CEP), was administered to a rat model of RA-associated interstitial lung disease to observe the degree of improvement in both joint swelling and pulmonary fibrosis. HFL1 cells were stimulated with TGF-ß1 to observe the expression of p-JAK2. Then, different concentrations of related gene inhibitors (JAK2, TGFß-R1/2, and p-STAT3) or silencers (STAT3, JAK2) were administered to HFL1 cells, and the expression levels of related proteins were detected to explore the underlying mechanisms of action. RESULTS: CEP not only reduced the degree of joint swelling and inflammation in rats but also improved lung function, inhibited the pro-inflammatory factors IL-1ß and IL-6, reduced lung inflammation and collagen deposition, and alleviated lung fibrosis. CEP decreased the expression levels of TGFß-R2, p-SMAD, p-STAT3, and ECM proteins in rat lung tissues. TGF-ß1 induced HFL1 cells to highly express p-JAK2, with the most pronounced expression at 48 h. The levels of p-STAT3, p-SMAD3, and ECM-related proteins were significantly reduced after inhibition of either JAK2 or STAT3. CONCLUSION: JAK2 inhibitors may be an important and novel immunotherapeutic drug that can improve RA symptoms while also delaying or blocking the development of associated pulmonary fibrotic disease. The mechanism may be related to the downregulation of p-STAT3 protein via inhibition of the JAK2/STAT signaling pathway, which affects the phosphorylation of SMAD3.

Reversible effects on female rat fertility with abrocitinib, a Janus kinase 1 inhibitor.

BACKGROUND: Abrocitinib is a Janus kinase (JAK) 1 selective inhibitor approved for the treatment of atopic dermatitis. Female reproductive tissues were unaffected in general toxicity studies, but an initial female rat fertility study resulted in adverse effects at all doses evaluated. A second rat fertility study was conducted to evaluate lower doses and potential for recovery. METHODS: This second study had 4 groups of 20 females each administered abrocitinib (0, 3, 10, or 70 mg/kg/day) 2 weeks prior to cohabitation through gestation day (GD) 7. In addition, 2 groups of 20 rats (0 or 70 mg/kg/day) were dosed for 3 weeks followed by a 4-week recovery period before mating. All mated females were evaluated on GD 14. RESULTS: No effects were observed at ≤10 mg/kg/day. At 70 mg/kg/day (29x human exposure), decreased pregnancy rate, implantation sites, and viable embryos were observed. All these effects reversed 4 weeks after the last dose. CONCLUSIONS: Based on these data and literature on the potential role of JAK signaling in implantation, we hypothesize that these effects may be related to JAK1 inhibition and, generally, that peri-implantation effects such as these, in the absence of cycling or microscopic changes in nonpregnant female reproductive tissues, are anticipated to be reversible.

Biologics and targeted synthetic medicines for ulcerative colitis and Crohn's disease.

Ulcerative colitis and Crohn's disease are chronic inflammatory bowel diseases. Recent pivotal phase 3 trials involving treatments like interleukin-23-, sphingosin-1-phosphate- and Janus kinase inhibitors have demonstrated notable effectiveness. However, they have also unveiled significant side effects such as herpes zoster, lymphopenia and bradycardia. The introduction of novel treatments raises valid concerns necessitating increased collaboration with diverse medical specialities to address potentially severe side effects, and this is vital for enhancing the future care of individuals with inflammatory bowel diseases, as argued in this review.

Comparison of Old and New Systemic Treatments for Moderate to Severe Atopic Dermatitis.

PURPOSE OF REVIEW: Historically, systemic treatments for atopic dermatitis (AD) primarily consisted of immunosuppressive agents such as corticosteroids and Disease Modifying Antirheumatic Drugs (DMARDS), which provided symptomatic relief but often had long-term adverse effects. Newer treatments have shown significant efficacy with less side effects in clinical trials. This review discusses and compares conventional and newer systemic treatments for AD. RECENT FINDINGS: Newer medications for AD including dupilumab, tralokinumab, lebrikizumab, and oral JAK inhibitors have been shown to be safe and efficacious. High dose cyclosporine and dupilumab were more effective than methotrexate and azathioprine in improving clinical signs of AD. High-dose upadacitinib was shown in another meta-analysis to be most effective in the measured outcomes but had the highest frequency of adverse events. Targeted biologic treatments are increasingly favored over traditional immunosuppressive treatments of AD. Treatment can be individualized based on potency, adverse side effects, mechanism of action, and administration preference. Ongoing research continues to expand treatment options for AD.

Effectiveness and safety of filgotinib in rheumatoid arthritis patients: data from the GISEA registry.

OBJECTIVES: The aim of this study was to evaluate the effectiveness and safety profile of filgotinib, a JAK1 preferential inhibitor, in rheumatoid arthritis (RA) patients included in Italian GISEA (Group for the Study of Early Arthritis) registry. METHODS: Data from RA patients treated with filgotinib, recorded in the GISEA registry, were analysed. Disease activity scores and patient-reported outcomes (PROs) were assessed at baseline, as well as during 12-month follow-up. A difficult-to-treat (D2T) RA patient was defined according with EULAR criteria. Retention rate of filgotinib was estimated by the Kaplan-Meier method and factors influencing drug discontinuation were estimated by Cox regression models. RESULTS: 246 RA patients (female 89%, 57.6±12.2 years old) started filgotinib, mostly as second (22%) or further (43.9%) b/tsDMARDs line of treatment. At 3 and 12 months, 18.8% and 27.5% of patients achieved Clinical Diseases Activity Index based remission and 30.1% and 37.7% obtained a visual analogue scale of pain ≤20 (all p<0.01 vs. baseline). Filgotinib survival rate was 84.5% at the 6-month and 75.8% at 12-month follow-up, and was comparable either in monotherapy or combination therapy, and irrespective of glucocorticoid intake. b/tsDMARD naive patients had the lowest hazard ratio (HR) of filgotinib discontinuation (HR 0.29, 95%CI 0.14-0.64), while D2T-RA the highest (HR 1.82, 95%CI 1.01-3.3). Eight patients (3.3%) discontinued filgotinib due to adverse events. CONCLUSIONS: In an Italian real-life setting, filgotinib is confirmed to be safe and with a good effectiveness profile both in monotherapy and without glucocorticoids.

Long-term effectiveness and safety of upadacitinib for Japanese patients with moderate-to-severe atopic dermatitis: a real-world clinical study.

BACKGROUND: Previous clinical trials presented efficacy and safety of Janus kinase 1 inhibitor upadacitinib through 52 weeks for moderate-to-severe atopic dermatitis (AD). OBJECTIVES: To assess the effectiveness and safety of upadacitinib through 48 weeks in real-world clinical practice for Japanese AD patients (aged ≥12 years). METHODS: This retrospective study included 287 patients with moderate-to severe AD treated with 15 mg (n = 216) or 30 mg (n = 71) of upadacitinib daily. Effectiveness was assessed using eczema area severity index (EASI) scores, atopic dermatitis control tool (ADCT), peak pruritus-numerical rating scale (PP-NRS), and investigator's global assessment (IGA). Safety was evaluated through the incidence of treatment-emergent adverse events. RESULTS: From baseline, EASI, ADCT, PP-NRS, and IGA rapidly reduced at week 4, and the reduction was maintained until week 48 of treatment with upadacitinib at both doses. Achievement rates of EASI 75, EASI 90, and EASI 100 at week 48 were 63.5, 30.2, and 7.9 in 15 mg group, and 77.4, 54.8, and 3.2% in 30 mg group, respectively. Acne and herpes zoster were frequent, but no serious adverse events occurred. CONCLUSIONS: Upadacitinib was therapeutically effective and tolerable for moderate-to-severe AD through 48 weeks in real-world clinical practice.

The Role of JAK/STAT Signaling Pathway and Its Downstream Influencing Factors in the Treatment of Atherosclerosis.

Atherosclerosis is now widely considered to be a chronic inflammatory disease, with increasing evidence suggesting that lipid alone is not the main factor contributing to its development. Rather, atherosclerotic plaques contain a significant amount of inflammatory cells, characterized by the accumulation of monocytes and lymphocytes on the vessel wall. This suggests that inflammation may play a crucial role in the occurrence and progression of atherosclerosis. As research deepens, other pathological factors have also been found to influence the development of the disease. The Janus kinase/signal transducer and activator of transcription (JAK/STAT) pathway is a recently discovered target of inflammation that has gained attention in recent years. Numerous studies have provided evidence for the causal role of this pathway in atherosclerosis, and its downstream signaling factors play a significant role in this process. This brief review aims to explore the crucial role of the JAK/STAT pathway and its representative downstream signaling factors in the development of atherosclerosis. It provides a new theoretical basis for clinically affecting the development of atherosclerosis by interfering with the JAK/STAT signaling pathway.

Protocol for a systematic review and meta-analysis on Janus kinase inhibitors in the management of vitiligo.

BACKGROUND: Vitiligo is a disease that affects people of all skin shades and can impact their quality of life. Reliable evidence on the effectiveness and adverse events associated with the recent use of Janus kinase (JAK) inhibitors to treat vitiligo is needed. This protocol for a systematic review and meta-analysis seeks to collect evidence from both randomized controlled trials (RCTs) and observational studies to determine the effectiveness and patient-centered outcomes concerning treatment with JAK inhibitors. METHODS: We will conduct a systematic review of the literature for RCTs and observational studies that used upadacitinib, ritlecitinib, brepocitinib, ifidancitinib, cerdulatinib, deglocitinib, baricitinib, tofacitinib, and ruxolitinib JAK inhibitors as treatments for vitiligo compared to placebo, no treatment, or combination therapies. We will systematically search from inception in Epistemonikos, MEDLINE, Scopus, Cochrane Central Register of Controlled Trials, EMBASE, ClinicalTrials.gov, PsycINFO, Allied and Complementary Medicine Database, Latin American and Caribbean Health Sciences Literature, Web of Science Core Collection, relevant preprint servers, and the gray literature. Ethics approval was not sought as the protocol and systematic review will not involve human participants, but rather summarized and anonymous data from studies. Primary outcomes include quality of life, percentage repigmentation, decreased vitiligo within 1 year or more, lasting repigmentation after a 2-year follow-up, cosmetic acceptability of repigmentation and tolerability or burden of treatment, and adverse events. Secondary outcomes are patient and study characteristics. We will include full-text articles, preprints, and clinical trial data in any language and all geographic regions. For data sources unavailable in English, we will obtain translations from global collaborators via the Cochrane Engage network. We will exclude articles for which sufficient information cannot be obtained from the authors of articles and systematic reviews. At least two investigators will independently assess articles for inclusion and extract data; reliability will be assessed before subsequent selection and data extraction of remaining studies. The risk of bias and certainty of evidence with Grading of Recommendations Assessment, Development, and Evaluation guidelines will be assessed independently by at least two investigators. We will estimate treatment effects by random-effects meta-analyses and assess heterogeneity using I2. Data that cannot be included in the meta-analysis will be reported narratively using themes. DISCUSSION: The proposed systematic review and meta-analysis describe the methods for summarizing and synthesizing the evidence on the effectiveness and patient-centered outcomes concerning the treatment of vitiligo with JAK inhibitors that were recently approved for this indication. To disseminate further the results of our systematic review, we plan to present them at international conferences and meetings. Our findings will provide robust evidence to facilitate decision-making at the policy or practitioner level. SYSTEMATIC REVIEW REGISTRATION: PROSPERO CRD42023383920.

Comparison of active tuberculosis occurrence associated with Janus kinase inhibitors and biological DMARDs in rheumatoid arthritis.

OBJECTIVES: This study aimed to evaluate the risk of tuberculosis associated with the use of Janus kinase (JAK) inhibitors or biological disease-modifying antirheumatic drugs (bDMARDs) in patients diagnosed with rheumatoid arthritis (RA) in South Korea. METHODS: In this nationwide matched-cohort study, we retrospectively identified adult patients with new-onset RA from the National Health Insurance Service database who were prescribed bDMARDs or JAK inhibitors and recently underwent latent tuberculosis infection (LTBI) screening during 2012‒2021, and followed them up until the end of 2022 for the development of active tuberculosis. HRs were estimated using Cox proportional hazards regression in a propensity score-matched cohort. RESULTS: Among 16 760 matched patients with RA (3352 JAK inhibitor users and 13 408 bDMARD users), 18.8% received tuberculosis preventive therapy for LTBI. Overall, JAK inhibitor users had a significantly lower risk of tuberculosis than bDMARD users (HR (95% CI)=0.37 (0.22 to 0.62)). Among the patients treated for LTBI, patients with low treatment adherence had a significantly higher risk than those without LTBI (HR (95% CI)=2.78 (1.74 to 4.44)). Patients without LTBI and using JAK inhibitors had a significantly lower risk of tuberculosis across all ages and sexes compared with bDMARD users. CONCLUSION: Patients with RA using JAK inhibitors have a significantly lower risk of active tuberculosis than bDMARD users in South Korea; however, patients with RA having LTBI are equally at risk regardless of the treatment received (JAK inhibitor vs bDMARD). Therefore, vigilant tuberculosis monitoring, especially in patients with low adherence to tuberculosis preventive therapy, is essential.