DEVELOPMENT AND VALIDATION OF STABILITY INDICATING HPTLC METHOD FOR DETERMINATION OF IGURATIMOD IN BULK AND PHARMACEUTICAL DOSAGE FORM

Objective: The objective of the work was to develop and validate stability indicating HPTLC method for the estimation of Iguratimod. Methods: The method employed HPTLC aluminium pre-covered silica gel 60 GF254 plates (10 cm × 10 cm with 250 μm layer thickness) as stationary phase while the solvent system was n-Hexane: Ethyl Acetate (5:5 v/v) with densitometric scanning at 256 nm. Sample was applied as a band of 8 mm width using Camag 100 μl sample syringe (Hamilton, Switzerland) using a linomat 5 applicator (Camag, Switzerland). Migration distance was 80 mm. Further the sample was subjected for stress conditions under acid and base hydrolysis, oxidation, thermal, neutral and photolytic conditions. Method validation done according to ICH Q2 (R1) guidelines. Results: Retention factor (Rf) of the drug was 0.41±0.02. The linearity of the method was found to be within the concentration range of 200-1200 ng/band with R2= 0.983. Limit of detection and limit of quantification were found to be 34.69 and 105.12 ng/band respectively. The % mean recovery was found to be 100.38±0.83. Stress results showed that there is degradation in acid and base conditions but two degradant peaks were observed only under alkaline stress condition Conclusion: The developed method found to be accurate, simple and precise. Method is successfully employed for quantification of the drug under various stress conditions

Add-on effectiveness of methotrexate or iguratimod in patients with rheumatoid arthritis exhibiting an inadequate response to Janus kinase inhibitors: The ANSWER cohort study

This is a pre-copyedited, author-produced version of an article accepted for publication in Modern Rheumatology following peer review. The version of record, Ebina K., Hirano T., Maeda Y., et al. Add-on effectiveness of methotrexate or iguratimod in patients with rheumatoid arthritis exhibiting an inadequate response to Janus kinase inhibitors: The ANSWER cohort study. Modern Rheumatology 33, 690 (2023) is available online at: https://academic.oup.com/mr/article-abstract/33/4/690/6664276?redirectedFrom=fulltext and https://doi.org/10.1093/mr/roac092Objectives: This multicenter, retrospective study evaluated the effectiveness of add-on methotrexate (MTX) or iguratimod (IGU) in patients with rheumatoid arthritis exhibiting an inadequate response to Janus kinase inhibitors (JAKis). Methods: Forty-five patients were treated with new additional MTX (n = 22) or IGU (n = 23) and followed for 6 months. Patients' background is as follows: age, 59.2 years; disease activity score of 28 joints with C-reactive protein (DAS28-CRP), 3.4; clinical disease activity index, 15.7; biological disease-modifying antirheumatic drug (DMARD)-switched cases, 77.8%; first JAKi cases, 95.6%; and JAKi treatment: tofacitinib (n = 25), baricitinib (n = 17), upadacitinib (n = 2), and peficitinib (n = 1) for 9.6 months. Results: Thirty-five patients continued the combination therapy for 6 months without a significant change in concomitant glucocorticoid or other conventional synthetic DMARDs. DAS28-CRP (MTX, 3.6 to 2.6, p < 0.05; IGU, 3.3 to 2.1, p < 0.001) and clinical disease activity index (MTX, 16.7 to 8.8, p < 0.05; IGU, 14.6 to 6.5, p < 0.01) improved significantly from baseline. Using the 2019 European League Against Rheumatism criteria, 45.4% (MTX) and 39.1% (IGU) achieved moderate or good response and 40.9% (MTX) and 39.1% (IGU) achieved American College of Rheumatology 20% improvement criteria. Conclusions: Adding MTX or IGU to inadequate responders of JAKi can be considered as a complementary treatment

The add-on effectiveness and safety of iguratimod in patients with rheumatoid arthritis who showed an inadequate response to tocilizumab

Objectives: To evaluate the effectiveness of add-on iguratimod (IGU) in patients with rheumatoid arthritis (RA) who showed an inadequate response to tocilizumab (TCZ), especially patients who were intolerant of an effective dose of methotrexate (MTX). Methods: Thirty-one patients with RA (22 women, age 62.4 years, disease duration 13.8 years, prior TCZ duration 35.7 months, 25 intravenous [8 mg/kg/4 weeks] and 6 subcutaneous [162 mg/2 weeks] TCZ treatments, concomitant MTX 8.5 mg/week [35.5%], and prednisolone (PSL) 4.3 mg/day [25.8%]) who showed an inadequate response to TCZ (disease activity score assessing 28 joints with C-reactive protein [DAS28-CRP] 2.9, clinical disease activity index [CDAI] 15.0, 28 secondary inadequate responders) were treated with additional IGU (final dose 41.7 mg/day) and enrolled in this 24-week, multicenter, retrospective study. Results: Twenty-nine patients (93.5%) continued the treatment for 24 weeks (one dropped out for pneumonia and one for digestive symptoms). The TCZ and the concomitant dose and rate of conventional synthetic disease-modifying antirheumatic drugs (csDMARDs) (MTX, salazosulfapyridine [SASP], and tacrolimus [TAC]) were not significantly changed during this period. Outcome measures improved significantly, as follows: DAS28-CRP from 2.9 to 1.7 (p <.001); CDAI from 15.0 to 6.0 (p <.001); modified Health Assessment Questionnaire (mHAQ) from 0.8 to 0.6 (p <.05); and rheumatoid factor (RF) from 382.1 to 240.3 IU/mL (p <.001). Using the EULAR criteria, 64.5% achieved a moderate response, and 51.6% achieved ACR 20 at 24 weeks. Conclusion: Adding IGU to inadequate responders to TCZ may be a promising and safe complementary treatment option.Ebina K., Miyama A., Tsuboi H., et al. The add-on effectiveness and safety of iguratimod in patients with rheumatoid arthritis who showed an inadequate response to tocilizumab. Modern Rheumatology 29, 581 (2019); https://doi.org/10.1080/14397595.2018.1486939

Effect of iguratimod on diclofenac metabolism by CYP2C9 in rats and human recombinant CYP2C9 yeast cells

Iguratimod (IGU, also known as T-614), a novel disease modifying antirheumatic drug intended to cure patients with rheumatoid arthritis (RA). The purpose of this study is to evaluate the effect of IGU on the pharmacokinetics of CYP2C9 probe drug diclofenac and its metabolite 4′-hydroxy diclofenac in vivo and in vitro. In in vivo experiments, 24 rats were randomly assigned to three groups consisting of the control group (Normal saline), low dose IGU group (10 mg/kg) and high dose IGU group (30 mg/ kg). Blood samples were collected from orbital sinuses vein before 1 hour and serial times of giving diclofenac (15 mg/kg) to all the rats. Plasma concentration of diclofenac and its metabolite 4´-hydroxy diclofenac were assayed by high performance liquid chromatography. Pharmacokinetic parameters were assessed by Winnonlin 6.4 pharmacokinetic software. Moreover, in vitro studies were performed in recombinant human CYP2C9 yeast cell system. IGU at low dose showed no significant differences in the pharmacokinetic parameters of diclofenac and 4-hydroxy diclofenac in vivo when compared with control group (p&gt;0.005). However, at the high dose of IGU, the pharmacokinetic parameters of 4´-hydroxy metabolite of diclofenac increase in half-life (T1/2) and mean area under the curve (AUC0→24), while a decrease in mean clearance (CL, mL/h/kg) and volume of distribution Vz (mL/kg). In addition, in in vitro study, high doses of IGU reduces the metabolism rate of diclofenac. IGU at high dose significantly increase the pharmacokinetics parameters of 4´-hydroxy diclofenac in rats. Additionally, it also showed the potent inhibitory effect on diclofenac metabolism in recombinant human CYP2C9 yeast cells

Research progress on the clinical application and mechanism of iguratimod in the treatment of autoimmune diseases and rheumatic diseases

Autoimmune diseases are affected by complex pathophysiology involving multiple cell types, cytokines, antibodies and mimicking factors. Different drugs are used to improve these autoimmune responses, including nonsteroidal anti-inflammatory drugs (NSAIDs), corticosteroids, antibodies, and small molecule drugs (DMARDs), which are prevalent clinically in the treatment of rheumatoid arthritis (RA), etc. However, low cost-effectiveness, reduced efficacy, adverse effects, and patient non-response are unattractive factors driving the development of new drugs such as iguratimod. As a new disease-modifying antirheumatic drug, iguratimod has pharmacological activities such as regulating autoimmune disorders, inflammatory cytokines, regulating immune cell activation, differentiation and proliferation, improving bone metabolism, and inhibiting fibrosis. In recent years, clinical studies have found that iguratimod is effective in the treatment of RA, SLE, IGG4-RD, Sjogren ‘s syndrome, ankylosing spondylitis, interstitial lung disease, and other autoimmune diseases and rheumatic diseases. The amount of basic and clinical research on other autoimmune diseases is also increasing. Therefore, this review systematically reviews the latest relevant literature in recent years, reviews the research results in recent years, and summarizes the research progress of iguratimod in the treatment of related diseases. This review highlights the role of iguratimod in the protection of autoimmune and rheumatic bone and related immune diseases. It is believed that iguratimod’s unique mode of action and its favorable patient response compared to other DMARDs make it a suitable antirheumatic and bone protective agent in the future

Network-Based In Silico Analysis of New Combinations of Modern Drug Targets with Methotrexate for Response-Based Treatment of Rheumatoid Arthritis

Background: Methotrexate (MTX), sulfonamides, hydroxychloroquine, and leflunomide have consistently resulted in remission with relatively mild to moderate adverse effects in patients with rheumatoid arthritis (RA). Modern medications outperform traditional treatments in that they target the pathological processes that underlie the development of RA. Methods: Following PRISMA guidelines, the authors accomplished a systematic review of the clinical efficacy of RA drugs, including the biologics such as Tumor Necrosis Factor-alpha inhibitors (TNF-α i) like Etanercept, Infliximab, Golimumab, and Adalimumab, kinase inhibitors (JAK inhibitors including Baricitinib and Tofacitanib), SyK inhibitors like Fos-tamatinib, MAPK inhibitors such as Talmapimod, T-cell inhibitors (Abatacept), IL6 blockers (Tocilizumab), and B cells depleters (Rituximab). These drugs have been found to increase remission rates when combined with MTX. A bioinformatics-based network was designed applying STRING-MODEL and the DrugBank database for the aforementioned drugs and MTX and, finally, employed for this systematic review. Results: Current research demonstrates that non-TNF-α inhibitor biologicals are particularly helpful in treating patients who did not respond well to conventional medications and TNF-α inhibitors. Despite being effective, these innovative drugs have a higher chance of producing hazardous side effects. The in silico investigations suggested an uncovered molecular interaction in combining MTX with other biological drugs. The STRINGMODEL showed that DHFR, TYMS, and ATIC, as the receptors of MTX, interact with each other but are not connected to the major interacted receptors. Conclusions: New game-changing drugs including Mavrilimumab, Iguratimod, Upadacitinib, Fenebrutinib, and nanoparticles may be crucial in controlling symptoms in poorly managed RA patients. Emerging therapeutic targets like Toll-like 4 receptors, NLRP3 inflammasome complexes, and mesenchymal stem cells can further transform RA therapy