JAK Inhibitors Research Articles

Efficacy and Safety of Filgotinib in Rheumatoid Arthritis Patients Aged over and under 65 Years (ENANTIA-65).

According to recent data, the age of patients could represent an important risk factor for MACE (major cardiovascular events), cancer, and VTE (venous thromboembolism) during treatment with JAK inhibitors in rheumatoid arthritis. We decided to analyze the population involved in the ReLiFiRa study by identifying two groups of patients: 65 years or more and less than 65 years of age, evaluating the efficacy and tolerability of 200 mg of Filgotinib daily. Of the 120 ReLiFiRa patients, 54 were younger than 65 years old and 66 patients were 65 years old or older. The data of efficacy and tolerability of treatment with FIL 200 mg daily for 6 months were evaluated. After six months of treatment, FIL was effective in both age groups. In both groups, the median values of steroid DAS28, CDAI, ERS, PCR, tender joints, swollen joints, VAS, HAQ, PGA patients, and PGA physicians were reduced with a statistically significant difference comparing these values with the baseline values. The difference in age did not impact the effectiveness of the drug. The lipid profile data also did not demonstrate significant differences between the two age groups; however, the comparison between younger vs. older patients' populations regarding the total cholesterol/HDL ratio and LDL/HDL ratio shows a statistically significant difference: total cholesterol/HDL 3.4 (2.12-3.66) vs. 3.64 (3.36-4.13) p = 0.0004, LDL/HDL 1.9 (0.98-2.25) vs. 2.41 (2.04-2.73) p = 0.0002. There are no differences regarding the atherogenic index (LDL-C/HDL-C) and coronary risk index (TC/HDL-C) compared to baseline. After six months of treatment with FIL, the older population group showed a higher level of LDL and a lower level of HDL compared to younger patients. The atherogenic index and coronary risk index are higher in patients aged ≥ 65 years, but interestingly, there were no differences when comparing the 6-month data to baseline values. This condition highlights the impact of typical risk factors that act independently of treatment with Filgotinib.

Practical Management of the JAK1 Inhibitor Abrocitinib for Atopic Dermatitis in Clinical Practice: Special Safety Considerations.

Abrocitinib, an oral, once-daily, Janus kinase (JAK)1-selective inhibitor, is approved for the treatment of adults and adolescents with moderate-to-severe atopic dermatitis (AD). Abrocitinib has shown rapid and sustained efficacy in phase3 trials and a consistent, manageable safety profile in long-term studies. Rapid itch relief and skin clearance are more likely to be achieved with a 200-mg daily dose of abrocitinib than with dupilumab. All oral JAK inhibitors are associated with adverse events of special interest and laboratory changes, and initial risk assessment and follow-up monitoring are important. Appropriate selection of patients and adequate monitoring are key for the safe use of JAK inhibitors. Here, we review the practical use of abrocitinib and discuss characteristics of patients who are candidates for abrocitinib therapy. In general, abrocitinib may be used in all appropriate patients with moderate-to-severe AD in need of systemic therapy, provided there are no contraindications, e.g., in patients with active serious systemic infections and those with severe hepatic impairment, as well as pregnant or breastfeeding women. For patients aged ≥ 65years, current long-time or past long-time smokers, and those with risk factors for venous thromboembolism, major adverse cardiovascular events, or malignancies, a meticulous benefit-risk assessment is recommended, and it is advised to start with the 100-mg dose, when abrocitinib is the selected treatment option.

Akkermansia muciniphila outer membrane protein regulates recruitment of CD8+ T cells in lung adenocarcinoma and through JAK-STAT signalling pathway.

As a Gram-negative anaerobic bacterium, Akkermansia muciniphila (AKK) participates in the immune response in many cancers. Our study focused on the factors and molecular mechanisms of AKK affecting immune escape in lung adenocarcinoma (LUAD). We cultured AKK bacteria, prepared AKK outer membrane protein Amuc_1100 and constructed a subcutaneous graft tumour mouse model. A549, NCI-H1395 cells and mice were respectively treated with inactivated AKK, Amuc_1100, Ruxolitinib (JAK inhibitor) and RO8191 (JAK activator). CD8+ T cells that penetrated the membrane were counted in the Transwell assay. The toxicity of CD8+ T cells was evaluated by lactate dehydrogenase assay. Western blot was applied to determine JAK/STAT-related protein and PD-L1 expression, whilst CCL5, granzyme B and INF-γ expression were assessed through enzyme-linked immunosorbent assay (ELISA). The proportion of tumour-infiltrating CD8+ T cells and the levels of granzyme B and INF-γ were determined by flow cytometry. AKK markedly accelerated A549 and NCI-H1395 recruiting CD8+ T cells and enhanced CD8+ T cell toxicity. Amuc_1100 purified from AKK exerted the same promoting effects. Besides, Amuc_1100 dramatically suppressed PD-L1, p-STAT and p-JAK expression and enhanced CCL5, granzyme B and INF-γ expression. Treatment with Ruxolitinib accelerated A549 and NCI-H1395 cells recruiting CD8+ T cells, enhanced CD8+ T cell toxicity, CCL5, granzyme B and INF-γ expression, and inhibited PD-L1 expression. In contrast, the RO8191 treatment slowed down the changes induced by Amuc_1100. Animal experiments showed that Amuc_1100 was found to increase the number of tumour-infiltrating CD8+ T cells, increase the levels of granzyme B and INF-γ and significantly inhibit the expression of PD-L1, p-STAT and p-JAK, which exerted an antitumour effect invivo. In conclusion, through inhibiting the JAK/STAT signalling pathway, AKK outer membrane protein facilitated the recruitment of CD8+ T cells in LUAD and suppressed the immune escape of cells.

Inhibition of the Janus kinase protein (JAK1) by the A. Pyrethrum Root Extract for the treatment of Vitiligo pathology. Design, Molecular Docking, ADME-Tox, MD Simulation, and in-silico investigation

This study delves into the therapeutic efficacy of A. pyrethrum in addressing vitiligo, a chronic inflammatory disorder known for inducing psychological distress and elevating susceptibility to autoimmune diseases. Notably, JAK inhibitors have emerged as promising candidates for treating immune dermatoses, including vitiligo. Our investigation primarily focuses on the anti-vitiligo potential of A. pyrethrum root extract, specifically targeting N-alkyl-amides, utilizing computational methodologies. Density Functional Theory (DFT) is deployed to meticulously scrutinize molecular properties, while comprehensive evaluations of ADME-Tox properties for each molecule contribute to a nuanced understanding of their therapeutic viability, showcasing remarkable drug-like characteristics. Molecular docking analysis probes ligand interactions with pivotal site JAK1, with all compounds demonstrating significant interactions; notably, molecule 6 exhibits the most interactions with crucial inhibition residues. Molecular dynamics simulations over 500ns further validate the importance and sustainability of these interactions observed in molecular docking, favoring energetically both molecules 6 and 1; however, in terms of stability, the complex with molecule 6 outperforms others. DFT analyses elucidate the distribution of electron-rich oxygen atoms and electron-poor regions within heteroatoms-linked hydrogens. Remarkably, N-alkyl-amides extracted from A. pyrethrum roots exhibit similar compositions, yielding comparable DFT and Electrostatic Potential (ESP) results with subtle distinctions. These findings underscore the considerable potential of A. pyrethrum root extracts as a natural remedy for vitiligo.

Cost-Utility Analysis of TNF-α Inhibitors, B Cell Inhibitors, and JAK Inhibitors Versus csDMARDs for Rheumatoid Arthritis Treatment.

Rheumatoid arthritis (RA) is a progressive and debilitating disease, causing persistent joint pain that limits daily activities requiring long-term treatment. Newer targeted therapies expand RA treatment options, but their high cost necessitates a focus on cost effectiveness. To address this, we aim to conduct a cost-utility analysis of these newer RA pharmacotherapies to support evidence-based policy decision-making. We analyzed the cost-utility of sequential treatment with TNF-α, B cell and JAK-inhibitors compared with conventional synthetic disease-modifying antirheumatic drugs (csDMARDs) for RA treatment in methotrexate (MTX) nonresponders. We used a Markov model with lifetime horizon and 6-month cycles from an Indian health system perspective. Costs (INR 2022) and quality-adjusted life years (QALYs) were used to determine the incremental cost-effectiveness ratios (ICERs) at a cost-effectiveness threshold of India's gross domestic product (GDP) per capita (2022). We assessed uncertainty using univariate, probabilistic sensitivity, and scenario analyses. Despite additional QALYs, TNF-α, B cell, and JAK inhibitors were not cost-effective for treating moderate-to-severe patients with RA unresponsive to csDMARDs (including MTX) in India, as increased costs outweighed their clinical benefits. ICERs ranged from 10,46,206 to 31,09,207Indian Rupees in the base case analysis, exceeding three times India's GDP per-capita [approximately USD $13,287 to $39,487 and GBP £10,776 to £32,025]. Sensitivity analyses confirmed the results' robustness. Scenario analysis suggested that a cost reduction of over 75% in drug prices could make most of the interventions cost effective compared with csDMARDs. TNF-α, B cell, and JAK-inhibitors are not cost-effective compared with csDMARDs for patients with RA who have not responded to MTX in India at the current prices. Cost-effectiveness estimates were highly influenced by drug pricing variations. Therefore, reducing the prices of these interventions could enhance affordability, potentially leading to their inclusion in publicly funded health programs.

Pharmacokinetics of Anti-rheumatic Drugs Methotrexate and Tofacitinib with its Metabolite M9 in Rats by UPLC-MS/MS.

Tofacitinib is an oral JAK inhibitor for the treatment of rheumatoid arthritis (RA). The clinical efficacy and safety of an administered tofacitinib, either monotherapy or in combination with conventional synthetic disease-modifying anti-rheumatic drugs, mainly methotrexate (MTX), have been evaluated. The high plasma concentration with delayed medicine clearance may affect the liver and/or kidney functions. In this study, an ultra-performance liquid chromatography-tandem mass spectrometry (UPLC- MS/MS) method for the quantitative analysis of methotrexate, tofacitinib, and metabolite M9 in plasma of Sprague Dawley (SD) rats was developed, and its effectiveness was validated as well. Methotrexate, tofacitinib, M9 and fedratinib (internal standard, IS) were separated by gradient elution. The chromatography was performed on an Acquity BEH C18 (2.1 mm × 50 mm, 1.7 μm) column with the mobile phases of acetonitrile and 0.1% formic acid aqueous solution with different proportions at the flow rate of 0.30 mL/min. In the positive ionization mode, the analyzes were detected using a Xevo TQ-S triple quadrupole tandem mass spectrometer, with the following mass transition pairs: m/z 313.12 → 148.97 for tofacitinib, m/z 329.10 → 165.00 for M9 and m/z 455.12 → 308.05 for methotrexate. The obtained results manifested good calibration linearity over the ranges of tofacitinib at 0.1-100 ng/mL, M9 at 0.05-100 ng/mL, and methotrexate at 0.05-100 ng/mL. The lower limit of quantifications (LLOQs) of methotrexate, tofacitinib and M9 were 0.05 ng/mL, 0.1 ng/mL and 0.05 ng/mL, respectively. Intra-day and inter-day accuracy values were confirmed with a range of -6.3% to 12.7%, while intra-day and inter-- day precision values were ≤14.4%. Additionally, recoveries were greater than 86.5% for each compound without significant matrix effects. The currently established analytical method exhibited great potential for the evaluation of plasma concentrations of methotrexate, tofacitinib and M9 simultaneously, greatly reducing the detection time, which would serve as a supplementary role in formulating dose decisions to achieve personalized treatment, identify drugs that cause adverse reactions and finally, to assess drug-drug interactions on clinical studies.

Phase 2 Trial of Deucravacitinib in Psoriatic Arthritis: Biomarkers Associated With Disease Activity, Pharmacodynamics, and Clinical Responses.

Our objective was to evaluate the association of serum biomarkers with baseline psoriatic arthritis (PsA) disease activity, pharmacodynamic effects of deucravacitinib on biomarker levels, and the relationship between biomarkers and clinical responses to deucravacitinib. The phase 2 trial (ClinicalTrials.gov identifier: NCT03881059) randomly assigned 203 patients with PsA 1:1:1 to placebo, deucravacitinib at 6 mg once daily (QD), or deucravacitinib at 12 mg QD. Serum biomarkers associated with the interleukin 23 (IL-23) pathway (IL-17A, β-defensin [BD-2], and IL-19), type I interferon pathway, inflammation, and collagen matrix turnover were measured by immunoassay. Clinical responses (≥75% improvement from baseline in the Psoriasis Area and Severity Index [PASI75] and ≥20% improvement from baseline in American College of Rheumatology criteria [ACR20] responses) were measured at week 16. Hematologic variables were also assessed. IL-17A, BD-2, and IL-19 had a modest association with PASI scores (r = 0.4, r = 0.56, and r = 0.5, respectively) at baseline. In deucravacitinib groups, IL-17A, BD-2, IL-19, C-X-C motif ligand 9 (CXCL9), CXCL10, C-reactive protein, matrix metalloproteinase 3, and collagen type 4 degradation marker levels were significantly reduced at week 16 versus baseline (P < 0.01); higher levels of IL-23 pathway-associated biomarkers predicted higher PASI75 and ACR20 response rates in deucravacitinib-treated patients. Significantly higher PASI75 response rates were seen in patients with high baseline IL-17A (odds ratio 15.76) and BD-2 levels (odds ratio 15.41) versus low baseline IL-17A and BD-2 levels. Changes in hematologic variables that are characteristic of JAK inhibition were not observed with deucravacitinib. Deucravacitinib significantly impacted biomarkers associated with Tyk2 signaling pathways of key inflammatory cytokines, including IL-23 and type I interferon, and those related to collagen matrix turnover. These biomarkers may predict treatment responses to deucravacitinib.

Functional and Structural Characterization of Clinical-Stage Janus Kinase 2 Inhibitors Identifies Determinants for Drug Selectivity.

Janus kinase 2 (JAK2) plays a critical role in orchestrating hematopoiesis, and its deregulation leads to various blood disorders, most importantly myeloproliferative neoplasms (MPNs). Ruxolitinib, fedratinib, momelotinib, and pacritinib are FDA-/EMA-approved JAK inhibitors effective in relieving symptoms in MPN patients but show variable clinical profiles due to poor JAK selectivity. The development of next-generation JAK2 inhibitors is hampered by the lack of comparative functional analysis and knowledge of the molecular basis of their selectivity. Here, we provide mechanistic profiling of the four approved and six clinical-stage JAK2 inhibitors and connect selectivity data with high-resolution structural and thermodynamic analyses. All of the JAK inhibitors potently inhibited JAK2 activity. Inhibitors differed in their JAK isoform selectivity and potency for erythropoietin signaling, but their general cytokine inhibition signatures in blood cells were comparable. Structural data indicate that high potency and moderate JAK2 selectivity can be obtained by targeting the front pocket of the adenosine 5'-triphosphate-binding site.

LACC1 deficiency leading to juvenile arthritis and anemia

ObjectiveJuvenile arthritis caused by loss-of-function LACC1 mutations is characterized by early onset of symmetric and chronic arthritis, associated with an elevation of inflammatory markers. We aimed to describe serum cytokine levels, explore the type I interferon pathway, and evaluate the efficacy of treatment in a patient presenting with polyarthritis and anemia caused by novel compound heterozygous variations in LACC1. MethodsClinical data of a patient with compound heterozygous variations in LACC1 was collected. Serum cytokine levels and IFN-stimulated cytokine genes were analyzed at diagnosis, at disease flare, and after treatment. Full-length cDNA of LACC1 was checked by RNA analysis. Single-cell RNA sequencing was performed in PBMCs. ResultsTwo novel variants in the LACC1 gene were identified in a patient presenting with polyarthritis and anemia. LACC1-cDNA was normally expressed in the healthy control, the target production at 1384 bp was not observed in the patient. Compared to nine patient controls with non-systemic juvenile idiopathic arthritis, serum interleukin(IL)-6 level was significantly elevated in the affected patient. The median IFN score for the patient, her mother, and controls were 118, 8, and 4.9, respectively. The combined treatment of JAK inhibitors with prednisone or tocilizumab led to a complete response, including remission of joint symptoms, resolution of anemia, reduced expression of IFN-stimulated cytokine genes, and normalized levels of inflammatory markers, including CRP, ESR, SAA, and serum IL-6. ConclusionLACC1 may play a crucial role in multiple inflammatory signaling pathways. The combination therapy of JAK inhibitors and tocilizumab may be effective for a subset of refractory patients.

A hierarchical cluster analysis for clinical profiling of tofacitinib treatment response in patients with rheumatoid arthritis.

Tofacitinib is the first oral JAK inhibitor approved for treating rheumatoid arthritis (RA). To enhance our understanding of tofacitinib drug response, we used hierarchical clustering to analyse the profiles of patient who responded to the treatment in a real-world setting. Patients who commenced on tofacitinib treatment were selected from 12 major rheumatology centres in Malaysia. The aim was to assess their response to tofacitinib defined as achieving DAS28-CRP/ESR ≤ 3.2 and DAS28 improvement > 1.2 at 12weeks. A hierarchical clustering analysis was performed using sociodemographic and clinical parameters at baseline. All 163 RA patients were divided into three clusters (Clusters 1, 2 and 3) based on specific clinical factors at baseline including bone erosion, antibody positivity, disease activity and anaemia status. Cluster 1 consisted of RA patients without bone erosion, antibody negative, low baseline disease activity measure and absence of anaemia. Cluster 2 comprised of patients without bone erosion, RF positivity, anti-CCP negativity, moderate to high baseline disease activity score and absence of anaemia. Cluster 3 patients had bone erosion, antibody positivity, high baseline disease activity and anaemia. The response rates to tofacitinib varied among the clusters: Cluster 1 had a 79% response rate, Cluster 2 had a 66% response rate, and Cluster 3 had a 36% response rate. The differences in response rates between the three clusters were found to be statistically significant. This cluster analysis study indicates that patients who are seronegative and have low disease activity, absence of bone erosion and no signs of anaemia may have a higher likelihood of benefiting from tofacitinib therapy. By identifying clinical profiles that respond to tofacitinib treatment, we can improve treatment stratification yielding significant benefits and better health outcomes for individuals with RA.

Harnessing immunity: Immunomodulatory therapies in COVID-19.

An overly exuberant immune response, characterized by a cytokine storm and uncontrolled inflammation, has been identified as a significant driver of severe coronavirus disease 2019 (COVID-19) cases. Consequently, deciphering the intricacies of immune dysregulation in COVID-19 is imperative to identify specific targets for intervention and modulation. With these delicate dynamics in mind, immunomodulatory therapies have emerged as a promising avenue for mitigating the challenges posed by COVID-19. Precision in manipulating immune pathways presents an opportunity to alter the host response, optimizing antiviral defenses while curbing deleterious inflammation. This review article comprehensively analyzes immunomodulatory interventions in managing COVID-19. We explore diverse approaches to mitigating the hyperactive immune response and its impact, from corticosteroids and non-steroidal drugs to targeted biologics, including anti-viral drugs, cytokine inhibitors, JAK inhibitors, convalescent plasma, monoclonal antibodies (mAbs) to severe acute respiratory syndrome coronavirus 2, cell-based therapies (i.e., CAR T, etc.). By summarizing the current evidence, we aim to provide a clear roadmap for clinicians and researchers navigating the complex landscape of immunomodulation in COVID-19 treatment.

Efficacy and Safety of Upadacitinib or Elsubrutinib Alone or in Combination for Patients With Systemic Lupus Erythematosus: A Phase 2 Randomized Controlled Trial.

The 48-week, phase 2 SLEek study (NCT03978520) evaluated the efficacy and safety of upadacitinib (JAK inhibitor) and elsubrutinib (BTK inhibitor) alone or in combination (ABBV-599) in adults with moderately to severely active systemic lupus erythematosus (SLE). Patients were randomized 1:1:1:1:1 to elsubrutinib 60 mg and upadacitinib 30 mg once daily (ABBV-599 high dose), elsubrutinib 60 mg and upadacitinib 15 mg once daily (ABBV-599 low dose), elsubrutinib 60 mg once daily (QD), upadacitinib 30 mg QD, or placebo QD. The primary endpoint was the proportion of patients achieving both Systemic Lupus Erythematosus Responder Index 4 (SRI-4) and glucocorticoid dose ≤10 mg QD at week 24. Additional assessments through week 48 included British Isles Lupus Assessment Group-Based Composite Lupus Assessment (BICLA) and Lupus Low Disease Activity State (LLDAS) responses, number of flares, time to first flare, and adverse events. The study enrolled 341 patients. The ABBV-599 low dose and elsubrutinib arms were discontinued after a planned interim analysis showed lack of efficacy (no safety concerns). More patients achieved the primary endpoint with upadacitinib (54.8%; P = 0.028) and ABBV-599 high dose (48.5%; P = 0.081) versus placebo (37.3%). SRI-4, BICLA, and LLDAS response rates were higher for both upadacitinib and ABBV-599 high dose versus placebo at weeks 24 and 48. Flares were reduced, and time to first flare through week 48 was substantially delayed with both upadacitinib and ABBV-599 high dose versus placebo. No new safety signals were observed beyond those previously reported for upadacitinib or elsubrutinib. Upadacitinib 30 mg alone or in combination with elsubrutinib (ABBV-599 high dose) demonstrated significant improvements in SLE disease activity and reduced flares and were well tolerated through 48 weeks.

Computational identification and experimental validation of potential inhibitors of JAK1 kinase from natural source for the effective treatment of colorectal adenocarcinoma

Colorectal cancer (CRC) has become a global threat worldwide with constantly increasing incidence and mortality rates every year, especially in the US and China. Janus kinase (JAK) is an intracellular non-receptor tyrosine that mediates the signal transducer and activator of transcription (STAT) which orchestrates cytokine signalling, oncogene expression, and modulation of transcription factors. Targeting JAK holds promise as a therapeutic strategy for CRC. This present study focused on natural products, due to their renowned for their diverse pharmacological properties including anticancer, antimicrobial, anti-proliferative, and antioxidant effects. Employing a range of bioinformatics analyses such as molecular docking, drug-likeness evaluation, ADME profiling, toxicity assessment, in silico cytotoxicity prediction, and molecular target identification, and in vitro assays such as cytotoxicity assay & ROS induction assay were performed to investigate the potency of the natural compounds. Among the screened compounds, Methyl betulate (L1), Epigallocatechin-3-gallate (EGCG) (L2), and Eriocalyxin B (L3) exhibited stronger binding affinities than the standard Golidocitinib (AZD4205). These compounds not only met Lipinski's criteria for drug-likeness and displayed favourable ADME properties but also demonstrated reduced toxicity profiles and exhibited promising activity against various kinases. Furthermore, molecular dynamics simulations revealed the stability of these compounds with JAK1. Notably, they also exhibited potent cytotoxicity and induced apoptosis in SW480 and HT29 colon adenocarcinoma cells. Consequently, the findings suggest that these three compounds hold potential as potent JAK1 inhibitors, warranting further investigation in future in vivo studies.

Combined JAK inhibition and PD-1 immunotherapy for non-small cell lung cancer patients.

Persistent inflammation driven by cytokines such as type-one interferon (IFN-I) can cause immunosuppression. We show that administration of the Janus kinase 1 (JAK1) inhibitor itacitinib after anti-PD-1 (programmed cell death protein 1) immunotherapy improves immune function and antitumor responses in mice and results in high response rates (67%) in a phase 2 clinical trial for metastatic non-small cell lung cancer. Patients who failed to respond to initial anti-PD-1 immunotherapy but responded after addition of itacitinib had multiple features of poor immune function to anti-PD-1 alone that improved after JAK inhibition. Itacitinib promoted CD8 T cell plasticity and therapeutic responses of exhausted and effector memory-like T cell clonotypes. Patients with persistent inflammation refractory to itacitinib showed progressive CD8 T cell terminal differentiation and progressive disease. Thus, JAK inhibition may improve the efficacy of anti-PD-1 immunotherapy by pivoting T cell differentiation dynamics.

Co-targeting JAK1/STAT6/GAS6/TAM signaling improves chemotherapy efficacy in Ewing sarcoma

Ewing sarcoma is a pediatric bone and soft tissue tumor treated with chemotherapy, radiation, and surgery. Despite intensive multimodality therapy, ~50% patients eventually relapse and die of the disease due to chemoresistance. Here, using phospho-profiling, we find Ewing sarcoma cells treated with chemotherapeutic agents activate TAM (TYRO3, AXL, MERTK) kinases to augment Akt and ERK signaling facilitating chemoresistance. Mechanistically, chemotherapy-induced JAK1-SQ phosphorylation releases JAK1 pseudokinase domain inhibition allowing for JAK1 activation. This alternative JAK1 activation mechanism leads to STAT6 nuclear translocation triggering transcription and secretion of the TAM kinase ligand GAS6 with autocrine/paracrine consequences. Importantly, pharmacological inhibition of either JAK1 by filgotinib or TAM kinases by UNC2025 sensitizes Ewing sarcoma to chemotherapy in vitro and in vivo. Excitingly, the TAM kinase inhibitor MRX-2843 currently in human clinical trials to treat AML and advanced solid tumors, enhances chemotherapy efficacy to further suppress Ewing sarcoma tumor growth in vivo. Our findings reveal an Ewing sarcoma chemoresistance mechanism with an immediate translational value.

Understanding mechanisms of JAK1 inhibition on synovial fibroblasts using combinatorial approaches of bulk and single cell RNAseq analyses.

The aim of these studies was to characterise the molecular effects of a tool JAK1 inhibitor on cultured primary fibroblast-like synoviocytes (FLS) from patients with rheumatoid arthritis (RA) through both total and individual cell analysis. RA-FLS cultures from 6 (Bulk RNA-seq) or 4 (ScRNA-seq) donors were pre-treated with various concentrations (100 nM and 1μM) of ABT-317 with/without exposure to 25% SEB-conditioned PBMC medium to mimic the RA inflammatory milieu. Cells were subjected to both bulk RNA-seq (36 libraries) and single cell RNA-seq (scRNA-seq; 24 libraries) to identify biological processes impacted by CM and ABT-317 treatments. In our bulk RNA-seq analysis, a total of 2,605 differentially expressed genes (DEGs) were identified between CM-stimulation and unstimulated groups, while 1,122 DEGs were found between ABT-317 1μM and DMSO in CM-stimulated groups using thresholds of log2 (fold change) ≥ |0.58| and FDR ≤ 10%. Both bulk and single cell mRNA analysis of RA-FLS treated with a combination of CM and ABT-317 demonstrated the expected changes in inflammatory pathways such as interferon and IL-6 signalling. However, other non-inflammation associated pathways were also altered by ABT-317. In addition, the single cell analysis highlighted that FLS segregate into distinctive clusters upon combination CM and ABT-317 treatment, suggesting JAK inhibition can drive RA-FLS into multiple heterogenous cell populations. Interestingly, one of the unique RA-FLS clusters that emerged from the CM and ABT-317 treatment showed matrix metalloproteinase-3 (MMP3)high expression as well as several gene signatures that are not found in any other ABT-317 derived clusters. JAK inhibition with ABT-317 is effective at globally inhibiting CM-induced pro- and non-inflammatory pathways in FLS cultures, but also results in several distinct fibroblast populations with unique gene-associated pathways. This study advances the molecular understanding of JAK1 inhibitor effects on fibroblasts that may contribute to clinical efficacy.

Comparison of anti-IL-6 receptor and JAK inhibitors in patients with rheumatoid arthritis from the real-world practice FIRST study.

A molecular-targeted drug that is suitable as the second choice for patients with rheumatoid arthritis (RA) who show an inadequate response to the first biological disease-modifying antirheumatic drug (bDMARD) is unknown. This study aimed to analyze the efficacy and safety of interleukin-6 receptor (IL-6Ri) and Janus kinase inhibitors (JAKis), often selected as molecular-targeted drugs for second or subsequent treatments. The efficacy and safety of JAKis and IL-6Ri were compared using propensity score-based inverse probability of treatment weighting (PS-IPTW) using propensity scores after 26 weeks of therapy in patients with RA. The remission rate at week 26, determined by the clinical disease activity index (CDAI), and the incidence of infection were higher in the JAKis than in the IL-6Ri group. The CDAI trajectories were divided into four according to the growth mixture modeling. IL-6Ri demonstrated greater efficacy in RA patients with ineffective to single bDMARD therapy compared with those with multiple ineffective bDMARDs. In patients who failed to respond to one bDMARD, there was no significant difference in the CDAI remission rate at week 26 between the JAKis (29.1%) and IL-6Ri (21.8%) groups (p= 0.21). However, for patients who did not respond to at least two bDMARDs, the CDAI remission rate at week 26 was higher in the JAKis than in the IL-6Ri group. IL-6Ri offers a superior balance of efficacy and safety compared with JAKis for RA patients unresponsive to one bDMARD. However, JAKis may suit patients who do not respond to multiple bDMARDs.

LncRNA SNHG1 enhances cartilage regeneration by modulating chondrogenic differentiation and angiogenesis potentials of JBMMSCs via mitochondrial function regulation

BackgroundCartilage is a kind of avascular tissue, and it is difficult to repair itself when it is damaged. In this study, we investigated the regulation of chondrogenic differentiation and vascular formation in human jaw bone marrow mesenchymal stem cells (h-JBMMSCs) by the long-chain noncoding RNA small nucleolar RNA host gene 1 (SNHG1) during cartilage tissue regeneration.MethodsJBMMSCs were isolated from the jaws via the adherent method. The effects of lncRNA SNHG1 on the chondrogenic differentiation of JBMMSCs in vitro were detected by real-time fluorescence quantitative polymerase chain reaction (RT-qPCR), Pellet experiment, Alcian blue staining, Masson’s trichrome staining, and modified Sirius red staining. RT-qPCR, matrix gel tube formation, and coculture experiments were used to determine the effect of lncRNA SNHG1 on the angiogenesis in JBMMSCs in vitro. A model of knee cartilage defects in New Zealand rabbits and a model of subcutaneous matrix rubber suppositories in nude mice were constructed for in vivo experiments. Changes in mitochondrial function were detected via RT-qPCR, dihydroethidium (DHE) staining, MitoSOX staining, tetramethyl rhodamine methyl ester (TMRM) staining, and adenosine triphosphate (ATP) detection. Western blotting was used to detect the phosphorylation level of signal transducer and activator of transcription 3 (STAT3).ResultsAlcian blue staining, Masson’s trichrome staining, and modified Sirius Red staining showed that lncRNA SNHG1 promoted chondrogenic differentiation. The lncRNA SNHG1 promoted angiogenesis in vitro and the formation of microvessels in vivo. The lncRNA SNHG1 promoted the repair and regeneration of rabbit knee cartilage tissue. Western blot and alcian blue staining showed that the JAK inhibitor reduced the increase of STAT3 phosphorylation level and staining deepening caused by SNHG1. Mitochondrial correlation analysis revealed that the lncRNA SNHG1 led to a decrease in reactive oxygen species (ROS) levels, an increase in mitochondrial membrane potential and an increase in ATP levels. Alcian blue staining showed that the ROS inhibitor significantly alleviated the decrease in blue fluorescence caused by SNHG1 knockdown.ConclusionsThe lncRNA SNHG1 promotes chondrogenic differentiation and angiogenesis of JBMMSCs. The lncRNA SNHG1 regulates the phosphorylation of STAT3, reduces the level of ROS, regulates mitochondrial energy metabolism, and ultimately promotes cartilage regeneration.

EPH43 Systematic Review of Real-World Data: Assessing Cancer, Major Adverse Cardiovascular Events, Venous Thromboembolism, Infection, and Mortality Risk Associated With Jak Inhibitors in Rheumatoid Arthritis Patients in the United States

EPH43 Systematic Review of Real-World Data: Assessing Cancer, Major Adverse Cardiovascular Events, Venous Thromboembolism, Infection, and Mortality Risk Associated With Jak Inhibitors in Rheumatoid Arthritis Patients in the United States

Efficacy and safety of levilimab in the treatment of rheumatoid arthritis in real-life clinical practice: first results of the HELIOS observational study

The efficacy and safety of levilimab (LVL) in patients with active rheumatoid arthritis (RA) has been confirmed in controlled clinical trials. This article presents the results of a preliminary analysis of a non-interventional observational study of LVL in RA patients. Objective: to evaluate the efficacy and safety of LVL in the treatment of patients with RA in real-world clinical practice. Materials and methods. The HELIOS study is a retrospective-prospective, multicenter, non-interventional study of retention rate of LVL therapy and the safety of LVL in patients with RA in real-world clinical practice. Patients received medical care, including LVL, according to routine clinical practice for the treatment of RA and Russian instructions for medical use of the drug. This article presents the results of an analysis of the efficacy and safety of LVL after 12 and 24 weeks of treatment. Efficacy was assessed using the DAS28-CRP/ESR, SDAI, CDAI and patient assessment of pain, fatigue and morning stiffness according to VAS (0–100 mm). Results and discussion. 524 patients from 42 medical centers in the Russian Federation were enrolled in the study from June 2022 to November 2023. The majority of patients were female (83.2 %) and the mean age of patients was 53 years. A statistically significant decrease in DAS28-CRP/ESR, SDAI, CDAI, patient assessment of pain, fatigue and morning stiffness (VAS) was observed after 12 and 24 weeks of treatment, regardless of previous treatment with biologics or Jak inhibitors (JAKi). LVL was well tolerated by patients, the most frequently reported adverse events were infections, changes in peripheral blood and laboratory abnormalities characteristic of treatment with IL-6R inhibitors. Conclusion. In real-world clinical practice, LVL has been shown to be highly effective and well tolerated in patients with RA when prescribed as the first biologic disease-modifying antirheaumatic drus (bDMARD) and after switching from other bDMARDs or JAKi.