Efficacy and safety evaluation of a combination of iguratimod and methotrexate therapy for active rheumatoid arthritis patients: a randomized controlled trial

Efficacy and safety of iguratimod in the treatment of rheumatic and autoimmune diseases: a meta-analysis and systematic review of 84 randomized controlled trials

Objective: To evaluate efficacy and safety of iguratimod (IGU) in the treatment of rheumatic and autoimmune diseases. Methods: Databases such as Pubmed, Embase, Sinomed were searched (as of July 2022) to collect randomized controlled trials (RCTs) of IGU in the treatment of rheumatic and autoimmune diseases. Two researchers independently screened the literature, extracted data, assessed the risk of bias of the included literature, and performed meta-analysis using RevMan 5.4 software. Results: A total of 84 RCTs and 4 types of rheumatic and autoimmune diseases [rheumatoid arthritis (RA), ankylosing spondylitis (AS), primary Sjögren's syndrome (PSS) and Autoimmune disease with interstitial pneumonia]. Forty-three RCTs reported RA and showed that IGU + MTX therapy can improve ACR20 (RR 1.45 [1.14, 1.84], p = 0.003), ACR50 (RR 1.80 [1.43, 2.26], p < 0.0000), ACR70 (RR 1.84 [1.27, 2.67], p = 0.001), DAS28 (WMD -1.11 [-1.69, -0.52], p = 0.0002), reduce ESR (WMD -11.05 [-14.58, -7.51], p < 0.00001), CRP (SMD -1.52 [-2.02, -1.02], p < 0.00001), RF (SMD -1.65 [-2.48, -0.82], p < 0.0001), and have a lower incidence of adverse events (RR 0.84 [0.78, 0.91], p < 0.00001) than the control group. Nine RCTs reported AS and showed that IGU can decrease the BASDAI score (SMD -1.62 [-2.20, -1.05], p < 0.00001), BASFI score (WMD -1.07 [-1.39, -0.75], p < 0.00001), VAS (WMD -2.01 [-2.83, -1.19], p < 0.00001), inflammation levels (decreasing ESR, CRP and TNF-α). Thirty-two RCTs reported PSS and showed that IGU can reduce the ESSPRI score (IGU + other therapy group: WMD -1.71 [-2.44, -0.98], p < 0.00001; IGU only group: WMD -2.10 [-2.40, -1.81], p < 0.00001) and ESSDAI score (IGU + other therapy group: WMD -1.62 [-2.30, -0.94], p < 0.00001; IGU only group: WMD -1.51 [-1.65, -1.37], p < 0.00001), inhibit the inflammation factors (reduce ESR, CRP and RF) and increase Schirmer's test score (IGU + other therapy group: WMD 2.18 [1.76, 2.59], p < 0.00001; IGU only group: WMD 1.55 [0.35, 2.75], p = 0.01); The incidence of adverse events in IGU group was also lower than that in control group (IGU only group: RR 0.66 [0.48, 0.98], p = 0.01). Three RCTs reported Autoimmune disease with interstitial pneumonia and showed that IGU may improve lung function. Conclusion: Based on current evidence, IGU may be a safe and effective therapy for RA, AS, PSS and autoimmune diseases with interstitial pneumonia. Systematic Review Registration: (CRD42021289489).

Serum proteomics analysis of biomarkers for evaluating clinical response to MTX/IGU therapy in early rheumatoid arthritis

Methotrexate (MTX) and iguratimod (IGU) are conventional synthetic disease modifying antirheumatic drugs widely used in the treatment of Rheumatoid arthritis (RA) in China. Although MTX combined with IGU can significantly inhibit the progression of RA, some patients do not respond to the treatment. The purpose of this study is to explore the difference of serum protein expression between RA patients with good and poor response to the combined therapy by label-free quantitative proteomic approach. From the proteomics data, a total of 782 proteins in the serum of RA patients were detected, and of which 9 were upregulated and 18 were downregulated in the good response group compared to poor response group. Among them, four significantly differentially expressed proteins (RELN, LDHA, MRC1 and TKT) were further validated by multiple reaction monitoring (MRM)-based quantification approach, and three of them (RELN, LDHA and MRC1) were confirmed to be correlated with the response to MTX/IGU therapy. Logistic regression and ROC analysis indicated that the combination of RELN, LDHA and MRC1 had good performance in evaluating the response. This result proved the different serum proteins signature fingerprint between response group and non-response group; and highlighted the potential of the label-free and mass spectrometry-based quantitative proteomic approach in screening biomarkers for evaluating clinical response to MTX/IGU therapy in RA.

The Effect and Safety of Iguratimod Combined With Methotrexate on Rheumatoid Arthritis: A Systematic Review and Meta-Analysis Based on a Randomized Controlled Trial

Background: Rheumatoid arthritis (RA) is a chronic systemic autoimmune disease with inflammatory synovitis. Iguratimod (IGU) combined with methotrexate (MTX) therapy may have better efficacy and safety.

Methods: First, we searched randomized controlled trials (RCTs) of IGU + MTX in the treatment of RA through literature databases (such as PubMed, Corkland Library, CNKI, etc.) and then conducted RCT quality assessment and data extraction. Finally, we used RevMan 5.3 for meta-analysis, STATA 15.0 for publication bias assessment, and GRADE tool for the evidence quality assessment of primary outcomes. This systematic review and meta-analysis were registered in PROSPERO (CRD42021220780).

Results: This systematic review and meta-analysis included 31 RCTs involving 2,776 patients. Compared with MTX alone, the ACR20, ACR50, and ACR70 of IGU + MTX are higher, while DAS28 is lower [ACR20: (RR 1.55, 95% CI 1.14–2.13, p = 0.006); ACR50: (RR 2.04, 95% CI 1.57–2.65, p < 0.00001); ACR70: (RR 2.19, 95% CI 1.44–3.34, p = 0.00003); DAS28: (weighted mean difference (WMD) −1.65, 95% CI −2.39 to −0.91, p < 0.0001)]. Compared with MTX + leflunomide, IGU + MTX has no significant difference in improving ACR20, ACR50, ACR70, but IGU + MTX improves DAS28 more significantly [ACR20: (RR 1.09, 95% CI 0.79–1.89, p = 0.59); ACR50: (RR 1.07, 95% CI 0.64–1.78, p = 0.81); ACR70: (RR 1.17, 95% CI 0.44–3.10, p = 0.76); DAS28: (WMD −0.40, 95% CI −0.42 to −0.38, p < 0.0001)]. Compared with the MTX + tripterygium subgroup and MTX-only subgroup, the incidence of adverse events of the IGU + MTX group is of no statistical significance [MTX only: (RR 0.99, 95% CI 0.87–1.13, p = 0.90); MTX + Tripterygium: (RR 0.73, 95% CI 0.29–1.85, p = 0.50)]. However, compared with MTX + leflunomide, the incidence of adverse events in the IGU + MTX group was lower (RR 0.74, 95% CI 0.62–0.88, p = 0.0009). The quality of ACR70 was high; the quality of adverse events and ACR50 test was moderate.

Conclusion: Compared with conventional therapy, IGU + MTX may be a safer and more effective therapy for RA patients. When the intervention method is (IGU 25 mg Bid, MTX 10–25 mg once a week), and the intervention lasts for at least 12 weeks, the curative effect may be achieved without obvious adverse events.

Clinical Efficacy of Methotrexate Combined with Iguratimod on Patients with Rheumatoid Arthritis and Its Influence on the Expression Levels of HOTAIR in Serum

Objective

This study was designed to explore the clinical efficacy of methotrexate combined with iguratimod on patients with rheumatoid arthritis (RA) and its influence on the expression levels of HOTAIR in serum.

Methods

A total of 268 RA patients were selected as research objects, 145 patients received methotrexate alone were used as a control group (CG), 123 patients received methotrexate combined with iguratimod were taken as a research group (RG), and serum of 60 healthy people undergoing physical examination was selected as a healthy control group (HCG). The therapeutic value of two therapeutic methods for RA was compared, and the HOTAIR expression in serum was detected by qRT-PCR.

Results

Compared with methotrexate used alone, the joint use of methotrexate and iguratimod could provide better clinical efficacy for RA patients and would not increase the incidence of adverse events. HOTAIR was highly expressed in the serum of RA patients, and its expression decreased after treatment.

Conclusion

Combination therapy of methotrexate and iguratimod is a safe and effective way to treat RA patients, which can be popularized clinically.

Effectiveness of iguratimod as monotherapy or combined therapy in patients with rheumatoid arthritis: a systematic review and meta-analysis of RCTs

Background

This study aims to evaluate the efficacy and safety of the iguratimod (IGU) as monotherapy or combined therapy in patients with rheumatoid arthritis (RA) by using meta-analysis.

Methods

We searched Medline, EMBASE, Cochrane library, CNKI, Wanfang medical network from initial to 30 June, 2020, for randomized clinical trials (RCTs). Two authors independently screened the studies via reading the title, abstract, and full text. The risk of bias in individual studies was assessed using the Cochrane Risk of Bias tool. STATA 12.0 was used for pooled analysis of all included studies.

Results

A total of 23 RCTs were included in this analysis. Meta-analysis showed that patients in the IGU monotherapy or combined therapy group had significantly higher ACR20 (OR = 1.97, 95% CI 1.29 to 3.00, P = 0.002), lower DAS28-CRP (SMD = −3.49, 95% CI −5.40 to −1.58, P < 0.001) and DAS28-ESR (SMD = −2.61, 95% CI −3.64 to −1.57, P < 0.001), as well as shorter duration of morning stiffness (SMD = −2.06, 95% CI −2.86 to −1.25, P < 0.001) and lower HAQ score (SMD = −0.91, 95% CI −1.61 to −0.21, P = 0.011), than those received other disease-modifying antirheumatic drugs (DMARDs) monotherapy (primarily comprising methotrexate). For the safety profile, IGU monotherapy had similar risks for gastrointestinal reactions (P = 0.070), leucopenia (P = 0.309), increment in transaminase (P = 0.321), increase of ALT (P = 0.051), and liver damage (P = 0.182) to methotrexate monotherapy, and IGU combined with other DMARDs therapy did not increase the risks of these AEs (P > 0.05).

Conclusions

Our evidence suggests that IGU is effective and tolerant as monotherapy or combined therapy especially with methotrexate in patients with active RA. IGU may be regarded as a potential alternative to methotrexate, and a preferable choice when combined with other DMARDs for the treatment of RA.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13018-021-02603-2.

Efficacy and safety of iguratimod combined with methotrexate vs. methotrexate alone in rheumatoid arthritis : A systematic review and meta-analysis of randomized controlled trials

The current systematic review and meta-analysis aims to evaluate the efficacy and safety of iguratimod (IGU) combined with methotrexate (MTX) versus MTX alone in rheumatoid arthritis (RA). Two independent investigators searched for original randomized controlled trials (RCTs) related to the combination of IGU and MTX in RA published before November 1, 2019, in PubMed, Cochrane Library, Embase, the China National Knowledge Infrastructure (CNKI), the Chinese Biomedical Literature Database (CBM), and WanFang Data. Additionally, we searched clinical trial registry websites. We assessed the methodological quality of the included trials using the Cochrane Collaboration tool and the seven-point Jadad scale. Statistical analyses were performed using Review Manager (RevMan) 5.3 (Copenhagen: The Nordic Cochrane Centre, The Cochrane Collaboration, 2014). Meta-regression and publication bias analyses were performed using Stata version 14 software (StataCorp., College Station, TX, USA). A total of 7 RCTs consisting of 665 participants, with 368 participants in the active arm and 297 in the placebo arm, were included in the meta-analysis. The American College of Rheumatology (ACR) value was better in the IGU + MTX group than in the MTX alone group, with a pooled relative risk (RR) for ACR20 (American College of Rheumatology 20% improvement criteria), ACR50, and ACR70 of 1.40 (95% CI, 1.13-1.74), 2.09 (95% CI, 1.67-2.61), and 2.24 (95% CI, 1.53-3.28), respectively. The results of the meta-analysis demonstrated that there was no statistical significance in adverse events (1.06 (95% CI, 0.92-1.23)). The combined treatment is an effective, safe, and economical treatment option for patients who do not respond well to methotrexate alone or for patients who cannot afford expensive biologics that have no confirmed efficacy.

Iguratimod combination therapy compared with methotrexate monotherapy for the treatment of rheumatoid arthritis: a systematic review and meta-analysis

OBJECTIVE

We estimated the relative efficacy and safety of iguratimod combination therapy compared with methotrexate monotherapy for the treatment of rheumatoid arthritis.

METHOD

We identified parallel randomized controlled trials from the Cochrane Central Register of Controlled Trials in The Cochrane Library (CENTRAL), MEDLINE, Embase, and other databases and trial registries for January April 2020. Independent assessment of the risk of bias and grading of the certainty of evidence was performed for the selected trials. We operated RevMan 5 software to compute the meta-analysis. We applied the random-effects model. The statistical methods applied were the Mantel-Haenszel method and the inverse-variance method for dichotomous and continuous outcomes, respectively.

RESULTS

We included 12 trials involving 1095 participants. Based on our result, patients on iguratimod combination are likely to have 3.53 (95% CI 2.22 to 5.60, moderate-certainty), 3.24, and 2.73 times higher odds for attaining American College of Rheumatology criteria (ACR) 20, 50, and 70, respectively, than methotrexate monotherapy. Disease state measured using DAS28 score (MD -0.71 score, 95% CI -1.03 to -0.39, very low certainty) and functional ability indicated by HAQ (Health Assessment Questionnaire) (MD -0.23, 95% CI -0.34 to -0.11, very low certainty) may also be better. The combination therapy also produced better results for C-reactive protein, erythrocyte sedimentation rate, pain intensity, and patient's and physician's global assessment of disease state. Incidence of adverse events were similar between the groups (OR 1.30, 95% CI 0.92 to 1.83, moderate-certainty).

CONCLUSION

Iguratimod combined with methotrexate may be considered a promising alternative for treating RA. Key Points • Iguratimod combination therapy produced better results in all the efficacy outcomes than methotrexate monotherapy. • Iguratimod combination therapy may be as safe as methotrexate monotherapy. • We recommend future clinical trials of iguratimod combination therapy in RA with iguratimod combined with DMARDs other than methotrexate and conducted in diverse population.

Iguratimod promotes transformation of mononuclear macrophages in elderly patients with rheumatoid arthritis by nuclear factor-κB pathway

BACKGROUND

The role of macrophages in rheumatoid arthritis (RA) and its mechanism have attracted much attention in RA pathogenesis. Macrophages accumulate in the synoviums of RA, and the proportion of M1 type pro-inflammatory macrophages is higher than that of M2 type anti-inflammatory macrophages, leading to the secretion of inflammatory molecules and the aggravation of inflammatory reaction, which has made macrophages a potential target of RA drugs. Iguratimod is a kind of cyclo-oxygenase-2 inhibitor that affects macrophage polarity. It is speculated that its anti-inflammatory and anti-rheumatic effects may be related to the regulation of macrophage M1/M2 ratio.

AIM

To investigate the effects of Iguratimod on the polarity of mononuclear macrophages in elderly patients with RA.

METHODS

Elderly patients with RA and joint effusion were selected, including 10 men and 25 women, with an average age of 66.37 ± 4.42 years. Patients were treated with oral administration of 25 mg Iguratimod (Iremod, State Food and Drug Administration Approval No. H20110084) twice daily for 12 wk. Disease Activity Score 28 and Health Assessment Questionnaire score were collected according to the disease severity before and after treatment. Venous blood and joint effusion fluid were collected, mononuclear macrophages were extracted and expression of cell surface markers CD86, CD64, CD163, and CD206 was analyzed by flow cytometry. The concentration of inflammatory factors interleukin (IL)-6, IL-1β, transforming growth factor-β, and IL-4 in the joint effusion fluid was analyzed by enzyme-linked immunosorbent assay. Expression of mononuclear cells inhibitor of nuclear factor-κB (IκB) and phosphorylated IκB in peripheral blood was analyzed by western blotting.

RESULTS

Disease Activity Score 28 score and Health Assessment Questionnaire score of patients treated with Iguratimod decreased significantly. The percentage of cell surface markers CD86 and CD64 decreased significantly, and the percentage of CD163 and CD206 increased significantly (P < 0.05). The inflammatory factors IL-6 and IL-1β decreased significantly, and transforming growth factor-β and IL-4 increased significantly. Western blot analysis showed that mononuclear cell inhibitor of nuclear factor-κB in peripheral blood was significantly increased after treatment, and its phosphorylation level was significantly decreased (P < 0.05).

CONCLUSION

Iguratimod can promote the transformation of mononuclear macrophages from M1 to M2 in elderly patients with RA by inhibiting the nuclear factor-κB pathway, thus improving symptoms of RA.

Effectiveness and safety of iguratimod treatment in patients with active rheumatoid arthritis in Chinese: A nationwide, prospective real-world study

Background

There is heterogeneity in the clinical manifestations and responses to drugs in RA patients due to variety of factors such as genes and environment. Despite advances in the treatment of rheumatoid arthritis (RA), approximately 40% of RA patients still do not achieve primary clinical outcomes in randomized trials, and its low remission rate and high economic consumption remain unresolved, especially in developing countries. Iguratimod (IGU) is a new disease-modifying anti-rheumatic drug (DMARD) with a low price that has demonstrated good efficacy and safety in clinical trials and was approved for active RA in China and Japan. As the most populous country in the Western Pacific region, it is warranted to conduct a study with a large scale of patients in a real-life setting. Our study confirms the new option for RA patients, which is potentially benificial for public health in developing countries.

Methods

This was a nationwide, prospective real-world study of IGU. Eligible subjects were active adult RA patients who aged 18 to 85 with or without multiple comorbidities such as hypertension and diabetes with DMARDs at a stable dosage for at least 12 weeks, or without ongoing DMARDs. A two-stage design was used for this study. In the first stage (the first 12 weeks), IGU 25 mg bid was added as monotherapy or to the background therapy, and in the second stage (the latter 12 weeks), adjustment of RA medicines other than IGU was allowed according to the participants’ disease activity. The primary endpoints were American College of Rheumatology 20% response (ACR20) 24 weeks and adverse events during 24 weeks. The secondary endpoints were ACR50 and ACR70 over 24 weeks, the changes of DAS28 and Health Assessment Questionnaire (HAQ) at week 12 and week 24 from baseline. The trial was registered with ClinicalTrials.gov, number NCT01554917.

Findings

Between March 2012 and January 2015, 1759 participants were enrolled, of whom 81•5% (1433/1759) completed the study. Notably, 1597 patients in the full analysis set were assessed for the effectiveness and 1751 patients were in the safety analysis set; 71•9% (1148/1597) of the patients achieved the primary endpoint of ACR20 response at week 24, and 51•7% (906/1751) patients had at least 1 adverse event (AE). The incidence of the clinical significant AE (grade≥3) of special interest was 3•4% (54 patients for grade 3 and 6 patients for grade 4), and 0•7% (13/1751) of patients developed SAEs associated with IGU. The most common clinical significant AEs were infection in 0•6% (10/1751) of the patients, abdominal discomfort in 0•5% (9/1751) of the patients including 0•2% (3/1751) gastric ulcer, fracture in 0•4% (7/1751), and increased alanine aminotransferase (ALT) in 0•2% (3/1751) of the patients. The secondary endpoint of ACR50 and ACR70 response rates at week 24 were 47•4% (757/1597) and 24•0% (384/1597). DAS28 was 4•11±1•27 and 3•75±1•32 at week 12 and 24, which was significantly decreased -1•40±1•10 and -1•75±1•26 compared with baseline (P<0•001) respectively. Changes in HAQ at week 12 and 24 from baseline were -7•4 ± 9•18 and -8•5 ± 9•97, respectively (all P<0•001). Stratified analysis results showed that the patients with shorter disease duration, male gender had better response to IGU. There was no significant difference in ACR20/50/70 responses between elderly patients(≥65 years) and younger patients(<65 years), IGU monotherapy or combined with other DMARDs. However, more fractures (1•1% vs 0•5%; P = 0•64) and infections (8•7% vs 7•9%; P = 0•69) were observed in elderly patients in our study.

Interpretation

Our results confirmed the effectiveness and safety of IGU as a new DMARD for active patients with RA as monotherapy or combination therapy.

Funding

This study was supported by “the 11th Five-Year-Plan for Science and Technology Support Program (2012ZX09104-103-01)”.

The Effectiveness and Retention Rate of Iguratimod in Japanese Rheumatoid Arthritis Patients with/without Methotrexate in Daily Medical Care

(1) Background: We evaluated the clinical response of iguratimod (IGU) in patients with rheumatoid arthritis (RA) being treated with or without methotrexate (MTX) over 54 weeks. (2) Methods: 106 patients with RA undergoing IGU were retrospectively observed. RA patients were divided into those treated with MTX+IGU (n = 35) and those treated with IGU (n = 71). The primary endpoint was the clinical response of the Disease Activity Score assessing 28 joints with C-reactive protein (DAS28-CRP) differences in the changes from baseline to 54 weeks between MTX+IGU and IGU groups. Secondary endpoints, such as the clinical response, retention rate, and safety, were evaluated. (3) Results: The DAS28-CRP difference in the changes between the two groups were −0.2. DAS28-CRP were significantly reduced from the baseline in the MTX+IGU and IGU groups (−1.43 and −1.20 from baseline, respectively). The retention rates were 71.4% in the MTX+IGU groups and 59.2% in the IGU groups (p = 0.16). Adverse events were observed in a total of 6 (17.1%) MTX+IGU patients and 20 (28.2%) IGU patients (p = 0.21). (4) Conclusions: IGU therapy may be a useful treatment option for patients who cannot be treated with MTX.

Anti-fibrotic effect of iguratimod on pulmonary fibrosis by inhibiting the fibroblast-to-myofibroblast transition

PURPOSE

Pulmonary fibrosis (PF) is a severe lung disease causing significant morbidity and mortality. PF pathogenesis is attributed to the fibroblast-to-myofibroblast transition (FMT) driven by the most potent pro-fibrogenic factor TGF-β1 activating the Smad3-dependent TGF-β1 canonical pathway. Iguratimod (IGU) is a novel anti-rheumatic drug that suppresses the secretion of inflammatory factors, but is also able to modulate the differentiation of multiple cells. Therefore, the aim of this work was to investigate the effect of IGU on FMT.

MATERIALS/METHODS

PF mouse model was induced in C57BL/6 male mice by bleomycin. The effect of IGU was assessed through the evaluation of lung morphology by H&E and through the collagen accumulation in the lung by Masson staining. Primary human lung fibroblasts (pHLFs) were also used to evaluate the effect of IGU in vitro on TGF-β1-stimulated cells, and proliferation, migration and invasion were measured, together with genes and proteins involved in FMT.

RESULTS

IGU attenuated bleomycin-induced PF in mice and improved the pathological changes in their lungs. In addition, IGU significantly inhibited proliferation, migration and invasion in TGF-β1-stimulated pHLFs without causing apoptosis. Moreover, IGU significantly reduced TGF-β1-induced increase of collagen I and III mRNA expression, thus reducing lung function impairment, and α-SMA, Smad2 and Smad3 phosphorylation, fibronectin expression and F-actin microfilament formation, thus attenuating FMT through the inhibition of the Smad3 pathway.

CONCLUSIONS

Our results collectively revealed the beneficial effect of IGU on the inhibition of FMT, thus suggesting that it might act as an effective anti-fibrotic agent in preventing the progression of PF.

Iguratimod treatment reduces disease activity in early primary Sjögren's syndrome: An open-label pilot study

OBJECTIVES

To evaluate the efficacy and safety of iguratimod in patients with early primary Sjögren's syndrome (pSS).

METHODS

Twenty-seven disease-modifying antirheumatic drug-naive female patients met the revised American-European Consensus Group criteria for pSS were enrolled in this open-label pilot study. Patients were treated with iguratimod 25 mg twice a day for 24 weeks. The disease activity was assessed with European League Against Rheumatism (EULAR) Sjögren's Syndrome Disease Activity Index (ESSDAI) and EULAR Sjögren's Syndrome Patient Reported Index (ESSPRI) at 12 and 24 weeks. Salivary and lacrimal gland function, laboratory, and subjective variables were also assessed. Generalized estimating equations were used to analyze parameters over time.

RESULTS

ESSDAI (median, 5 versus 2 versus 2, p < .01), IgG (median, 26.6 versus 22.4 versus 21.4 g/L, p < .01) and rheumatoid factor (median, 119.9 versus 94.1 versus 83.8 lU/mL, p < .01) levels decreased significantly during iguratimod treatment. ESSPRI, salivary and lacrimal gland function, fatigue and health-related quality of life did not change during treatment. One patient experienced thrombocytopenia, and no other serious adverse effects were observed.

CONCLUSION

In this study, iguratimod treatment is safe and effective for improving disease activity and laboratory parameters in early pSS patients.

The efficacy and mechanism for action of iguratimod in primary Sjögren's syndrome patients

PURPOSE

Primary Sjögren's syndrome (pSS) has been proven as a systemic autoimmune disorder (such as Sjogren's syndrome dry eye). This research aimed to evaluate potential treating effects of Iguratimod on pSS.

METHODS

Fifty pSS patients were enrolled and randomly divided into Conventional group and Iguratimod group. Improvement in pSS was evaluated every 4 weeks. pSS disease activity was evaluated with European League Against Rheumatism (EULAR) Sjögren's syndrome disease activity index (ESSDAI). Symptoms were evaluated by determining EULAR Sjögren's syndrome patient-reported index (ESSPRI), platelet (PLT), IgG and Schirmer I test. Peripheral blood B cell molecules (CD135, IgD, CD38, CD20) and human B cell-activating factor-receptor (BAFF-R) were analyzed with flow cytometry.

RESULTS

After treating for 12-weeks, pSS patients in Iguratimod and Conventional group showed a significant decrease in disease activity (ESSPRI, ESSDAI, PLT, IgG and Schirmer I test) comparing with baselines. Patients' ESSPRI (2.92 ± 0.19) and disease activity of ESSDAI (4.32 ± 0.29), PLT (95.64 ± 1.86), IgG (13.0 ± 0.45) and Schirmer I test (4.67 ± 0.31) in Iguratimod group were significantly lower compared to Conventional group (4.64 ± 0.15, 5.8 ± 2.08, 77.44 ± 1.41, 16.5 ± 0.44 and 2.25 ± 0.11) (p < 0.0001). Changes of ESSPRI, ESSDAI, PLT, IgG and Schirmer I test were remarkable observed between two groups (p < 0.001). Iguratimod and Conventional treatment demonstrated a significant reduction in total B cells in pSS patients compared with pre-treatment. The pSS patients from Iguratimod and Conventional group showed a significant decreased BAFF-R (61.82 ± 1.52, 74.07 ± 1.11) and CD38⁺IgD⁺ (48.08 ± 0.92, 62.66 ± 1.12) on B cells after treatment compared with baseline (92.26 ± 0.32, 91.53 ± 0.45, 84.39 ± 0.59, 85.04 ± 0.46) (p < 0.001). After treating 12 weeks, BAFF-R, CD38⁺IgD⁺ expression in Iguratimod group decreased significantly compared to Conventional group (p < 0.001).

CONCLUSIONS

Iguratimod alleviated symptoms and mediated adaptive-immunity balance by suppressing BAFF-R positive B cell in pSS patients.

Iguratimod as a New Drug for Rheumatoid Arthritis: Current Landscape

Iguratimod (IGU) is a novel synthetic small molecule disease modified anti-rheumatic drug approved only in Japan and China up to date. IGU plays an important immunomodulatory role in the synovial tissue of rheumatoid arthritis by inhibiting the production of immunoglobulins and cytokines and regulating T lymphocyte subsets. IGU also regulates bone metabolism by stimulating bone formation while inhibiting osteoclast differentiation, migration, and bone resorption. In clinical trials, IGU was shown to be superior to placebo and not inferior to salazosulfapyridine. Combined therapy of IGU with other disease-modifying anti-rheumatic drugs showed significant improvements for disease activity. IGU has good efficacy and tolerance as an additional treatment for rheumatoid arthritis patients with inadequate response to methotrexate and biological disease-modifying anti-rheumatic drugs. In this review, we summarize current landscape on the mechanism of action of IGU and its clinical effectiveness and safety. It is expected that further translational studies on IGU will pave the road for wider application of IGU in the treatment of autoimmune diseases other than rheumatoid arthritis.

Molecular mechanisms and clinical application of Iguratimod: A review

Iguratimod (IGU) is a novel small-molecule anti-rheumatic drug with remarkable effectiveness and good safety for the treatment of active rheumatoid arthritis. Its mechanism of action is related to its ability to act simultaneously on T and B lymphocytes. IGU can effectively inhibit expression of various inflammatory factors, inhibit B cells from producing immunoglobulins and autoantibodies, downregulate T-cell-mediated cellular immunity, accelerate bone formation, and exert some activity against anti-pulmonary fibrosis. In recent years, IGU has been gradually applied to the treatment of a variety of rheumatic diseases, such as Sjögren's syndrome, ankylosing spondylitis and systemic lupus erythematosus. This article reviews the mechanism of action and clinical research status of IGU, and provides reference for future research on its mechanism of action and clinical application.

Efficacy and safety of iguratimod on patients with relapsed or refractory IgG4-related disease

OBJECTIVE

To evaluate the therapeutic efficacy and safety of iguratimod on patients with relapsed or refractory IgG4-related disease (IgG4-RD).

METHODS

We conducted a retrospective single-center study in 17 IgG4-RD patients admitted to Peking University People's Hospital. Patients were given iguratimod, 25 mg, twice daily and clinical data were collected at 0, 12, and 24 weeks. The baseline treatments include prednisone, cyclophosphamide, leflunomide, mycophenolate mofetil, and methotrexate. Clinical manifestation, IgG4-RD responder index (IgG-RD RI), serological indexes, gland ultrasound findings, and adverse drug effect were recorded. IgG4-RD RI scores < 3 and declining ≥ 2 were recognized as complete response (CR); IgG4-RD RI scores declining ≥ 2 but remaining ≥ 3 were recognized as partial response (PR). If a patient's IgG4-RD RI score was 3 at the beginning, PR was considered as a 1-point decrease after the therapy.

RESULTS

Serum IgG4 decreased significantly from 708 (321-902) mg/dl at baseline to 446 (138-396) mg/dl at 24 weeks (P = 0.0016). IgG4-RD RI decreased significantly from 9.79 ± 3.07 at baseline to 3.57 ± 1.09 at 24 weeks (P < 0.0001). Overall, 2 (14.3%) patients achieved CR, 11 (78.6%) patients achieved PR, and 1 (7.14%) patient had no response to treatment at week 24. Serum IgG level and salivary glands major diameter also decreased significantly at week 12 and 24 after treatment.

CONCLUSION

Iguratimod can be a therapeutic strategy to achieve remission in relapsed or refractory IgG4-RD patients inadequately responding to corticosteroid treatment with or without other immunosuppressant treatment. Key messages • Iguratimod was effective for relapsed or refractory IgG4-RD patients. • Iguratimod can improve the clinical symptoms of patients, reduce the serum IgG and IgG4 levels, and can also reduce the volume of involved glands.

Autoimmune diseases in China

Autoimmune diseases, such as rheumatoid arthritis, systematic lupus erythematosus and Sjögren's syndrome, are a group of diseases characterized by the activation of immune cells and excessive production of autoantibodies. Although the pathogenesis of these diseases is still not completely understood, studies have shown that multiple factors including genetics, environment and immune responses play important roles in the development and progression of the diseases. In China, there are great achievements in the mechanisms of autoimmune diseases during the last decades. These studies provide new insight to understand the diseases and also shed light on the development of novel therapy.

Iguratimod: a valuable remedy from the Asia Pacific region for ameliorating autoimmune diseases and protecting bone physiology

Autoimmune diseases are affected by complex pathophysiology involving several cell types, cytokines, antibodies, and mimicking factors. Different drugs are used to ameliorate these autoimmune reactions, including nonsteroidal anti-inflammatory drugs (NSAIDs), corticosteroids, antiantibodies, and small molecular drugs (DMARDs), and they are clinically in vogue for diseases such as rheumatoid arthritis (RA). Nevertheless, low cost-effectiveness, reduced efficacy, adverse effects, and patient nonresponse are unappealing factors driving the development of new drugs such as iguratimod. Iguratimod is primarily used to ameliorate RA in Japanese and Chinese clinics. However, its efficacy against other autoimmune ailments is also under intense investigation, and the number of investigations is becoming increasingly larger with each passing day. The articular structure comprises synovium, ligaments, and bone. The latter is more complex than the others since it regulates blood cells and autoimmunity in addition to providing skeletal support to the body. Therefore, its protection is also of prime importance in RA and other autoimmune diseases. Herein, we have highlighted the role of iguratimod in autoimmune diseases and bone protection. We suggest that iguratimod’s unique mode of action compared with that of other DMARDs and its good patient response makes it a suitable antirheumatic and bone-protecting drug.

Efficacy of iguratimod vs. salazosulfapyridine as the first-line csDMARD for rheumatoid arthritis

Objectives: We retrospectively evaluated the retention rate and clinical responses following treatment for rheumatoid arthritis (RA) with iguratimod (IGU) vs. salazosulfapyridine (SASP) as the first-line conventional synthetic disease-modifying antirheumatic drug (csDMARD).Methods: We analyzed 197 RA patients who were treated with IGU or SASP as the initial treatment in the 3-year study period. The retention rate, clinical response, the dosage and percent user of prednisolone (PSL), and safety profiles were evaluated.Results: At month 36, the retention rates of the IGU and SASP groups were 52.4 vs. 32.1%. The rate of responders (good or moderate response) at month 36 was 85.8 vs. 65.2% in the IGU and SASP groups, respectively. At month 36 for the IGU and SASP groups, the percentages of PSL users were 16.7 vs. 46.7%, and the PSL dosage was 0.3 mg/d vs. 2.0 mg/d, respectively. The cumulative rates of any adverse event (AE) at month 36 were 19.8 vs. 29.2% in the IGU and SASP groups, respectively.Conclusion: IGU is a useful first-line csDMARD treatment for RA patients, showing a high retention rate and good efficacy without an increased risk of serious AEs, including serious infections. Our findings also indicate a PSL dose-sparing effect of IGU treatment.

2018 update of the APLAR recommendations for treatment of rheumatoid arthritis

AIM

To update recommendations based on current best evidence concerning the treatment of rheumatoid arthritis (RA), focusing particularly on the role of targeted therapies, to inform clinicians on new developments that will impact their current practice.

MATERIALS AND METHODS

A search of relevant literature from 2014 to 2016 concerning targeted therapies in RA was conducted. The RA Update Working Group evaluated the evidence and proposed updated recommendations using the Grading of Recommendations, Assessment, Development and Evaluations (GRADE) approach, to describe the quality of evidence and strength of recommendations. Recommendations were finalized through consensus using the Delphi technique.

RESULTS

This update provides 16 RA treatment recommendations based on current best evidence and expert clinical opinion. Recommendations 1-3 deal with the use of conventional synthetic disease-modifying antirheumatic drugs. The next three recommendations (4-6) cover the need for screening and management of infections and comorbid conditions prior to starting targeted therapy, while the following seven recommendations focus on use of these agents. We address choice of targeted therapy, switch, tapering and discontinuation. The last three recommendations elaborate on targeted therapy for RA in special situations such as pregnancy, cancer, and major surgery.

CONCLUSION

Rheumatoid arthritis remains a significant health problem in the Asia-Pacific region. Patients with RA can benefit from the availability of effective targeted therapies, and these updated recommendations provide clinicians with guidance on their use.

The three-year efficacy of iguratimod in clinical daily practice in patients with rheumatoid arthritis

Objectives: To assess the middle-term outcome of iguratimod (IGU) in rheumatoid arthritis (RA) patients. Methods: Sixty-nine RA patients (14 males and 55 females, mean age of 64.0 years) receiving IGU-containing therapies were enrolled. We divided these patients into three groups based on the treatment at the baseline: an IGU group, a methotrexate (MTX) plus IGU group, and a biologics plus IGU group. The baseline characteristics and clinical course were evaluated over three years. Predictive factors associated with the achievement of low disease activity (LDA) were statistically analyzed. Results: The survival rate of IGU therapy at 3 years was 40.6%. The disease activity was significantly decreased in the IGU group and MTX plus IGU group compared with the baseline. Furthermore, 38 patients (55.1%) were in remission or had LDA at 3 years. The patient gender, use of prednisolone (PSL) and DAS28-CRP at baseline were the factors associated with the achievement of remission or LDA at three years. Conclusion: IGU was effective without MTX or bDMARDs as well as in combination with MTX. A female gender, no use of PSL and a low DAS28-CRP at the initiation of IGU were associated with clinical remission or LDA achievement at three years.

Cancer chemotherapeutics in rheumatoid arthritis: A convoluted connection

Chemotherapy is one of the most popular therapeutic strategies to treat cancer. However, cancer chemotherapeutics have often been associated with impairment of the immune system, which might consequently lead to an augmented risk of autoimmune disorders, such as rheumatoid arthritis. Though the accurate mechanistic facets of rheumatoid arthritis induction have not been interpreted yet, a conglomeration of genetic and environmental factors might promote its etiology. What makes the scenario more challenging is that patients with rheumatoid arthritis are at a significantly elevated risk of developing various types of cancer. It is intriguing to note that diverse cancer chemotherapy drugs are also commonly used to treat symptoms of rheumatoid arthritis. However, a colossal multitude of such cancer therapeutics has demonstrated highly varied results in rheumatoid arthritis patients, including both beneficial and adverse effects. Herein, we attempt to present a holistic account of the variegated modalities of this complex tripartite cross-talk between cancer, rheumatoid arthritis and chemotherapy drugs in order to decode the sinuous correlation between these two appalling pathological conditions.

Effects of iguratimod on the levels of circulating regulators of bone remodeling and bone remodeling markers in patients with rheumatoid arthritis

This study aims to investigate the effect of iguratimod, a novel disease-modifying antirheumatic drug, alone or combined with methotrexate (MTX), on the serum levels of regulators of bone remodeling (receptor activator of nuclear factor-κB ligand (RANKL), osteoprotegerin (OPG), and Dickkopf-1 (DKK-1)) and bone remodeling markers (C-telopeptide of type I collagen (CTX-I) and procollagen type I N-terminal propeptide (PINP)) in patients with rheumatoid arthritis (RA). Patients with RA were treated with iguratimod, MTX, or their combination for 12 months. Serum samples were collected before treatment and 6 and 12 months afterwards. RANKL, OPG, DKK-1, CTX-I, and PINP levels were measured, and radiographic progression was assessed. The serum RANKL levels decreased after treatment for 6 and 12 months with iguratimod (median: baseline 565.00 pmol/L vs. 6 months 411.00 pmol/L vs. 12 months 212.00 pmol/L), MTX (median: baseline 562.50 pmol/L vs. 6 months 399.50 pmol/L vs. 12 months 163.50 pmol/L), and their combination (median: baseline 971.00 pmol/L vs. 6 months 272.50 pmol/L vs. 12 months 241.50 pmol/L). Combination therapy showed greater effects 6 months post-treatment compared to single-drug therapy. PINP levels increased significantly 12 months post-treatment with all therapies, but only the combination therapy led to decreased CTX-I levels. OPG and DKK-1 levels showed no significant changes. The three treatments showed no significant differences in radiographic progression. Iguratimod could stimulate bone formation and regulate the RANKL/RANK/OPG system rather than DKK-1levels. Its effects are comparable to those of MTX, and combination therapy showed stronger effects.

Identification of Iguratimod as an Inhibitor of Macrophage Migration Inhibitory Factor (MIF) with Steroid-sparing Potential

Macrophage migration inhibitory factor (MIF) is a pleiotropic cytokine that has been implicated in a broad range of inflammatory and oncologic diseases. MIF is unique among cytokines in terms of its release profile and inflammatory role, notably as an endogenous counter-regulator of the anti-inflammatory effects of glucocorticoids. In addition, it exhibits a catalytic tautomerase activity amenable to the design of high affinity small molecule inhibitors. Although several classes of these compounds have been identified, biologic characterization of these molecules remains a topic of active investigation. In this study, we used in vitro LPS-driven assays to characterize representative molecules from several classes of MIF inhibitors. We determined that MIF inhibitors exhibit distinct profiles of anti-inflammatory activity, especially with regard to TNFα. We further investigated a molecule with relatively low anti-inflammatory activity, compound T-614 (also known as the anti-rheumatic drug iguratimod), and found that, in addition to exhibiting selective MIF inhibition in vitro and in vivo, iguratimod also has additive effects with glucocorticoids. Furthermore, we found that iguratimod synergizes with glucocorticoids in attenuating experimental autoimmune encephalitis, a model of multiple sclerosis. Our work identifies iguratimod as a valuable new candidate for drug repurposing to MIF-relevant diseases, including multiple sclerosis.