Real-world effectiveness and safety of tofacitinib and abatacept in patients with rheumatoid arthritis.

Objective: We compared the 52-week effectiveness and safety of tofacitinib (TOF) and abatacept (ABT) in patients with RA in a real-world setting and investigated a role of human leucocyte antigens (HLA)-DRB1 shared epitope (SE) in the effectiveness. Methods: RA patients starting TOF (n = 187) and ABT (n = 183) were enrolled. Effectiveness was compared after reducing the selection bias to a minimum using the inverse probability of treatment weighting (IPTW) based on propensity scores. The influence of SE alleles on effectiveness was compared within each treatment group. A treatment group comparison was also performed within SE-positive and SE-negative groups. Results: Herpes zoster and some laboratory abnormalities were more frequent in the TOF group than in the ABT group. Patient characteristics did not differ significantly between treatment groups after adjustments with IPTW. The TOF group had a significantly higher proportion of DAS in 28 joints using ESR (DAS28-ESR) remission at week 52 than the ABT group. The DAS28-ESR at week 12 and thereafter was not affected by the copy number of SE alleles in the TOF group, but decreased significantly as the copy number increased in the ABT group. In SE-positive patients, remission and drug retention rates did not differ significantly between the two treatment groups. In SE-negative patients, the TOF group showed significantly higher remission and drug retention rates than the ABT group. Conclusion: The present results suggest that TOF is more effective with regard to remission at week 52 based on treatment responses in SE-negative RA patients.

Impact of the HLA-DRB1 shared epitope on responses to treatment with tofacitinib or abatacept in patients with rheumatoid arthritis.

OBJECTIVES: The aim of this study was to compare the clinical effectiveness of tofacitinib and abatacept and clarify the impact of the HLA-DRB1 shared epitope (SE) on responses to these treatments in patients with rheumatoid arthritis (RA). METHODS: After adjustments by propensity score matching, 70 out of 161 patients receiving tofacitinib and 70 out of 131 receiving abatacept were extracted. The clinical effectiveness of both drugs over 24 weeks and the impact of the copy numbers of SE on effectiveness outcomes were investigated. RESULTS: The percentage of patients in remission in the 28-joint count disease activity score using the erythrocyte sedimentation rate (DAS28-ESR) did not significantly differ between patients receiving tofacitinib and abatacept at week 24 (32% vs 37%, p = 0.359). The mean change at week 4 in DAS28-ESR from baseline was significantly greater in patients receiving tofacitinib than in those receiving abatacept (- 1.516 vs - 0.827, p = 0.0003). The percentage of patients in remission at week 4 was 30% with tofacitinib and 15% with abatacept (p = 0.016). When patients were stratified by the copy numbers of SE alleles, differences in these numbers did not affect DAS28-ESR scores of patients receiving tofacitinib. However, among patients receiving abatacept, DAS28-ESR scores were significantly lower in patients carrying 2 copies of SE alleles than in those carrying 0 copies at each time point throughout the 24-week period. Furthermore, the percentage of patients in remission with DAS28-ESR at week 24 was not affected by the copy numbers of SE alleles in patients receiving tofacitinib (p = 0.947), whereas it significantly increased as the copy numbers became higher in patients receiving abatacept (p = 0.00309). Multivariable logistic regression analyses showed a correlation between the presence of SE and DAS28-ESR remission in patients receiving abatacept (OR = 25.881, 95% CI = 3.140-213.351, p = 0.0025), but not in those receiving tofacitinib (OR = 1.473, 95% CI = 0.291-7.446, p = 0.639). CONCLUSIONS: Although the clinical effectiveness of tofacitinib and abatacept was similar at week 24, tofacitinib was superior to abatacept for changes from baseline in DAS28-ESR and the achievement of remission at week 4. SE positivity was associated with the achievement of DAS28-ESR remission by week 24 in patients receiving abatacept, but not in those receiving tofacitinib.

Abatacept is Efficacious in the Treatment of Older Patients with csDMARD-Refractory Rheumatoid Arthritis: A Prospective, Multicenter, Observational Study.

INTRODUCTION: Abatacept efficacy in older patients with rheumatoid arthritis (RA) has been primarily demonstrated via retrospective comparisons with younger patients. The objective of this study was to compare efficacy of abatacept in older vs. younger patients with RA, and efficacy of abatacept with that of conventional synthetic disease-modifying anti-rheumatic drugs (csDMARDs) in both age groups. METHODS: This prospective, multicenter, observational study (UMIN000014913) enrolled csDMARD-refractory patients without previous biological DMARD treatment. Abatacept (A) or csDMARDs (C) were administered at the treating physician's discretion to older (O, ≥ 65 years) and younger (Y, 20-64 years) patients, producing AO, AY, CO, and CY groups. Clinical efficacy after 24 weeks was evaluated using European League Against Rheumatism (EULAR) erythrocyte sedimentation rate response criteria. RESULTS: Overall, 202 patients were evaluated. Compared with the CO group, more patients in the AO group achieved a EULAR good or moderate response (p < 0.0001). Compared with the CY group, more patients in the AY group achieved a EULAR good or moderate response (p < 0.01). Similar proportions of patients in the AO and AY groups achieved a EULAR good response or a good or moderate response. Few adverse events were reported. CONCLUSIONS: This prospective study demonstrated that abatacept is efficacious and safe in older patients with RA and a history of being refractory to csDMARDs. Abatacept was shown to be more efficacious than adding or switching to a new csDMARD in both younger and older csDMARD-refractory patients with RA. TRIAL REGISTRATION: UMIN000014913.

Risk for malignancy in rheumatoid arthritis patients treated with biological disease-modifying antirheumatic drugs compared to the general population: A nationwide cohort study in Japan.

OBJECTIVES: To investigate and compare the risk for malignancy in rheumatoid arthritis (RA) patients treated with biologics in Japan to the general population. METHODS: Data for 14,440 patients from 335 institutions who were given infliximab, etanercept, adalimumab, golimumab, tocilizumab, or abatacept were retrieved from the SafEty of biologics in Clinical Use in Japanese patients with RhEumatoid arthritis (SECURE) database. RESULTS: We identified 333 incidents of malignancies in 320 patients during 49,320 patient-years (PY). The age- and sex-standardized incidence rate (ASR) (95% confidence interval [CI]) for overall malignancy of the SECURE cohort was 313.9/10(5) PY (271.4-361.3), and the standardized incidence rate ratio (SIR) (95% CI) was 0.745 (0.667-0.826). The ASR was decreased compared to the estimated incidence rate of malignancies in the Japanese general population (462.4/10(5) PY). The SIRs for site-specific nonhematopoietic malignancies of the SECURE cohort were not significantly elevated compared to the Japanese general population. A significant increase of SIR for malignant lymphoma (6.183, 95% CI, 4.809-7.643) was found in the SECURE cohort, similar to or slightly higher than the SIR previously reported from Japanese cohorts for RA patients. CONCLUSIONS: Continued vigilance with larger numbers of patients, longer observation periods, and inclusion of different biologics are recommended.

Clinical characteristics and risk factors for Pneumocystis jirovecii pneumonia in patients with rheumatoid arthritis receiving adalimumab: a retrospective review and case-control study of 17 patients.

OBJECTIVES: To investigate the clinical characteristics and risk factors of Pneumocystis jirovecii pneumonia (PCP) in rheumatoid arthritis (RA) patients treated with adalimumab. METHODS: We conducted a multicenter, retrospective, case-control study to compare RA patients treated with adalimumab with and without PCP. Data from 17 RA patients who were diagnosed with PCP and from 89 RA patients who did not develop PCP during adalimumab treatment were collected. RESULTS: For the PCP patients, the median age was 68 years old, with a median RA disease duration of eight years. The median length of time from the first adalimumab injection to the development of PCP was 12 weeks. At the onset of PCP, the median dosages of prednisolone and methotrexate were 5.0 mg/day and 8.0 mg/week, respectively. The patients with PCP were significantly older (p < 0.05) and had more structural changes (p < 0.05) than the patients without PCP. Computed tomography of the chest revealed ground-glass opacity without interlobular septal boundaries in the majority of the patients with PCP. Three PCP patients died. CONCLUSIONS: PCP may occur early in the course of adalimumab therapy in patients with RA. Careful monitoring, early diagnosis, and proper management are mandatory to secure a good prognosis for these patients.

Time-dependent increased risk for serious infection from continuous use of tumor necrosis factor antagonists over three years in patients with rheumatoid arthritis.

OBJECTIVE: To investigate associations between continuous treatments with tumor necrosis factor (TNF) antagonists and risk for developing serious infections (SIs) over 3 years in Japanese patients with rheumatoid arthritis (RA) enrolled in the Registry of Japanese RA Patients for Long-Term Safety (REAL) database. METHODS: We analyzed 727 RA patients who had started either infliximab or etanercept (the anti-TNF group; 1,480.1 patient-years [PY]) and 571 RA patients who had started conventional nonbiologic disease-modifying antirheumatic drugs (the unexposed group; 1,104.1 PY) at the time of enrollment in the REAL. We assessed the occurrence of SIs within a 3-year observation period, including the period after switching to other TNF antagonists, and all SIs, unlimited to the first one in each patient as reported in other studies, to evaluate the real safety of TNF antagonists in daily practice. RESULTS: The incidence rate of SIs per 100 PY was 5.54 (95% confidence interval [95% CI] 4.44-6.84) in the anti-TNF group and 2.72 (95% CI 1.87-3.83) in the unexposed group. Poisson regression analysis revealed that the relative risk (RR) of continuous use of TNF antagonists for SIs after adjusting for baseline and time-dependent covariates was significantly elevated both overall (1.97, 95% CI 1.25-3.19) and for the first year (2.40, 95% CI 1.20-5.03), but not for the second and third years combined (1.38, 95% CI 0.80-2.43). The adjusted RR for SIs of etanercept compared to infliximab was not significantly elevated. CONCLUSION: Continuous anti-TNF therapy was significantly associated with increased risks for developing SIs during, but not after, the first year.

Pneumocystis jirovecii pneumonia associated with etanercept treatment in patients with rheumatoid arthritis: a retrospective review of 15 cases and analysis of risk factors.

OBJECTIVES: The association of anti-tumor necrosis factor therapy with opportunistic infections in rheumatoid arthritis (RA) patients has been reported. The goal of this study was to clarify the clinical characteristics and the risk factors of RA patients who developed Pneumocystis jirovecii pneumonia (PCP) during etanercept therapy. METHODS: We conducted a multicenter, case-control study in which 15 RA patients who developed PCP were compared with 74 RA patients who did not develop PCP during etanercept therapy. RESULTS: PCP developed within 26 weeks following the first injection of etanercept in 86.7% of the patients. All PCP patients presented with a rapid and severe clinical course and the overall mortality was 6.7%. Independent risk factors were identified using multivariate analysis and included age ≥65 years [hazard ratio (HR) 3.35, p = 0.037], coexisting lung disease (HR 4.48, p = 0.009), and concomitant methotrexate treatment (HR 4.68, p = 0.005). In patients having a larger number of risk factors, the cumulative probability of developing PCP was significantly higher (p < 0.001 for patients with two or more risk factors vs. those with no risk factor, and p = 0.001 for patients with one risk factor vs. those with no risk factor). CONCLUSION: Physicians must consider the possibility of PCP developing during etanercept therapy in RA patients, particularly if one or more risk factors are present.

Pneumocystis jirovecii pneumonia associated with etanercept treatment in patients with rheumatoid arthritis: a retrospective review of 15 cases and analysis of risk factors.

Objectives The association of anti-tumor necrosis factor therapy with opportunistic infections in rheumatoid arthritis (RA) patients has been reported. The goal of this study was to clarify the clinical characteristics and the risk factors of RA patients who developed Pneumocystis jirovecii pneumonia (PCP) during etanercept therapy. Methods We conducted a multicenter, case-control study in which 15 RA patients who developed PCP were compared with 74 RA patients who did not develop PCP during etanercept therapy. Results PCP developed within 26 weeks following the first injection of etanercept in 86.7% of the patients. All PCP patients presented with a rapid and severe clinical course and the overall mortality was 6.7%. Independent risk factors were identified using multivariate analysis and included age ≥ 65 years [hazard ratio (HR) 3.35, p = 0.037], coexisting lung disease (HR 4.48, p = 0.009), and concomitant methotrexate treatment (HR 4.68, p = 0.005). In patients having a larger number of risk factors, the cumulative probability of developing PCP was significantly higher (p < 0.001 for patients with two or more risk factors vs. those with no risk factor, and p = 0.001 for patients with one risk factor vs. those with no risk factor). Conclusion Physicians must consider the possibility of PCP developing during etanercept therapy in RA patients, particularly if one or more risk factors are present.

Arthritic joint-targeting small interfering RNA-encapsulated liposome: implication for treatment strategy for rheumatoid arthritis.

RNA interference, mediated by small interfering RNA (siRNA), is effective in silencing genes with a high degree of specificity. To explore the therapeutic potential of systemically administered siRNA for rheumatoid arthritis (RA), we tested the complex of siRNA and the recently developed wrapsome (siRNA/WS) containing siRNA-encapsulated liposome in mice with collagen-induced arthritis (CIA). Mice with CIA received an intravenous injection of Cy5-labeled siRNA/WS. Fluorescence stereoscopic microscopy and flow cytometry were used to assess the siRNA/WS tissue distribution. The efficacy of siRNA-targeting tumor necrosis factor (TNF)-α/WS in CIA was evaluated by arthritis score. TNF-α mRNA levels in the joints were measured by real-time reverse transcriptase-polymerase chain reaction. The intensity of Cy5 fluorescence was higher in arthritic joints than in nonarthritic sites in Cy5-siRNA/WS-treated mice and remained higher up to 48 h after injection, compared with that in naked Cy5-siRNA-treated mice. Cy5 fluorescence intensity was higher in synovial cells than in splenocytes, bone marrow cells, and peripheral blood leukocytes. The majority of Cy5-positive synovial cells were CD11b⁺ with only a few CD3⁺ cells. Treatment with TNF-α siRNA/WS resulted in significant decreases in severity of arthritis and TNF-α mRNA level in the joints compared with control siRNA/WS. In conclusion, the use of our WS allowed efficient and targeted delivery of siRNAs to arthritic joints. The siRNA/WS was mainly incorporated into CD11b⁺ cells, including macrophages and neutrophils, in the inflamed synovium, suggesting its potential therapeutic effects in RA by silencing the expression of inflammatory molecules produced by these cells.

Incidence and risk factors for serious infection in patients with rheumatoid arthritis treated with tumor necrosis factor inhibitors: a report from the Registry of Japanese Rheumatoid Arthritis Patients for Longterm Safety.

OBJECTIVE: To compare tumor necrosis factor-α (TNF-α) inhibitors to nonbiological disease-modifying antirheumatic drugs (DMARD) for the risk of serious infection in Japanese patients with rheumatoid arthritis (RA). METHODS: Serious infections occurring within the first year of the observation period were examined using the records for patients recruited to the Registry of Japanese Rheumatoid Arthritis Patients for Longterm Safety (REAL), a hospital-based prospective cohort of patients with RA. The analysis included 1144 patients, 646 of whom were treated with either infliximab or etanercept [exposed group: 592.4 patient-years (PY)]. The remaining 498 patients received nonbiological DMARD with no biologics (unexposed group: 454.7 PY). RESULTS: In the unexposed group, the incidence rate for all serious adverse events (SAE) was 9.02/100 PY and for serious infections, 2.64/100 PY. In the exposed group, SAE occurred in 16.04/100 PY and serious infections in 6.42/100 PY. The crude incidence rate ratio comparing serious infections in the exposed group with the unexposed group was 2.43 (95% CI 1.27-4.65), a significant increase. A multivariate analysis revealed that the use of TNF inhibitors is a significant independent risk factor for serious infection (relative risk 2.37, 95% CI 1.11-5.05, p = 0.026). CONCLUSION: Our study has provided the first epidemiological data on Japanese patients with RA for the safety of TNF inhibitors compared to nonbiological DMARD for up to 1 year of treatment. Anti-TNF therapy was associated with a significantly increased risk for serious infections, compared to treatment with nonbiological DMARD.

A case of Behçet's disease with widespread perforating enteric ulcers preceded by a long history of peripheral gangrene.

Patients suffering from Behçet's disease (BD) with intestinal involvement often have an atypical disease course. The disease in many patients does not fully meet the diagnostic criteria defined by the International Study Group for Behçet's Disease, and instead such patients are diagnosed as having an incomplete type of BD according to the criteria of the BD Research Committee of Japan. The patient reported here developed uveitis and gangrene of the extremities as the initial symptoms and was treated with corticosteroid. After 16 years, the gangrene relapsed and multiple deep ulcers suddenly developed in the gastrointestinal tract, with oral ulcer and uveitis. The intestinal perforation was acute, progressive, severe, and extensive. With a diagnosis of incomplete BD with intestinal involvement, she was treated with high-dose glucocorticoid. However, uncontrollable gastrointestinal bleeding led to her death. Histopathological examination revealed that she suffered from intestinal and vascular BD, although gangrene of the extremities has rarely been reported as a manifestation of vascular BD. Thus, the disease course of this patient was characterized by the reappearance of peripheral gangrene after a long interval that preceded the devastating intestinal lesions.

Tacrolimus-induced pulmonary injury in rheumatoid arthritis patients.

BACKGROUND: Tacrolimus (TAC) was approved in Japan in 2005 for rheumatoid arthritis (RA) patients having inadequate response to other disease-modifying anti-rheumatic drugs. As of May 2007, spontaneous reports identified twenty-seven cases of exacerbation or new development of interstitial pneumonia among RA patients given TAC in Japan. OBJECTIVE: To describe the clinical and radiological characteristics of TAC-induced pulmonary injury (TIPI). PATIENTS AND METHODS: Eleven RA patients diagnosed with de novo pulmonary injury or exacerbation of IP during treatment with TAC were identified. Clinical, radiological, and laboratory data of ten of these cases were retrospectively analyzed. RESULTS: Baseline data for the ten patients were a mean age of 69.7 years; gender, 70% female; mean RA disease duration, 9.1 years; and pulmonary comorbidities, 90%. Six cases were classified as presumptive TAC-induced pulmonary injury (TIPI) and four as probable TIPI. Among the six presumptive cases, TIPI developed at an average of 84 days after initiation of treatment (n = 5) or four days after reinstitution of TAC (n = 1). Five cases were an exacerbation of pre-existing interstitial pneumonia and one was a de novo pulmonary injury. Radiological patterns of thoracic computed tomography (CT) scans of patients in the presumptive TIPI cases were hypersensitivity pneumonia like-pattern (n = 3), ground-glass opacity (n = 2), and organizing pneumonia-pattern (n = 1). All patients with presumptive TIPI were treated with high dosage glucocorticosteroids and one received concomitant immunosuppressants. Two of the six presumptive TIPI patients died. CONCLUSION: Rheumatologists should be aware of this rare but potentially life-threatening adverse event in RA patients receiving TAC.

Chemokine receptor expression and functional effects of chemokines on B cells: implication in the pathogenesis of rheumatoid arthritis.

INTRODUCTION: Accumulation of B cells in the rheumatoid arthritis (RA) synovium has been reported, and it has been thought that these cells might contribute to the pathogenesis of RA by antigen presentation, autoantibody production, and/or inflammatory cytokine production. Chemokines could enhance the accumulation of B cells in the synovium. The aims of this study were to determine chemokine receptor expression by B cells both in the peripheral blood of normal donors and subjects with RA, and at the inflammatory site in RA, and the effects of chemokines on B cell activation. METHODS: Cell surface molecule expression was analyzed by flow cytometry. Cellular migration was assessed using chemotaxis chambers. Cellular proliferation was examined by 3H-thymidine incorporation. Tumor necrosis factor (TNF) production was assayed by enzyme-linked immunosorbent assay. RESULTS: Significant numbers of peripheral blood B cells of healthy donors and subjects with RA expressed CC chemokine receptor (CCR)5 and CXCR3, and most B cells expressed CCR6, CCR7, CXCR4 and CXCR5. CCR5 expression was more frequent on CD27+ than CD27- peripheral blood B cells of healthy donors and RA. Synovial B cells more frequently expressed CCR5, but less often expressed CCR6, CCR7 and CXCR5 compared to peripheral blood in RA. Further functional analyses were performed on peripheral blood B cells from healthy donors. Migration of peripheral blood B cells, especially CD27+ B cells, was enhanced by CC chemokine ligand (CCL)20, CCL19, CCL21 and CXCL12. All four chemokines alone induced B cell proliferation; with CCL21 being the most effective. CCL21 also enhanced the proliferation of anti-immunoglobulin (Ig)M-stimulated B cells and blockade of CCR7 inhibited this effect. CCL20, CCL21 and CXCL12 enhanced TNF production by anti-IgM mAb-stimulated B cells. Finally, stimulation with CXCL12, but not CCL20, CCL19 and CCL21, enhanced inducible costimulator-ligand (ICOSL) expression by peripheral blood B cells of healthy donors and RA, but did not increase B cell-activating factor receptor or transmembrane activator and CAML-interactor. CONCLUSIONS: The data suggest that CCR5, CCR6, CCR7, CXCR3, CXCR4 and CXCR5 may be important for the B cell migration into the synovium of RA patients, and also their local proliferation, cytokine production and ICOSL expression in the synovium.

Pneumocystis jiroveci pneumonia in patients with rheumatoid arthritis treated with infliximab: a retrospective review and case-control study of 21 patients.

OBJECTIVE: To establish proper management of Pneumocystis jiroveci pneumonia (PCP) in rheumatoid arthritis (RA) patients treated with infliximab. PCP has been observed in 0.4% of patients with RA treated with infliximab in Japan. METHODS: Data from patients with RA (n = 21) who were diagnosed with PCP during infliximab treatment and from 102 patients with RA who did not develop PCP during infliximab therapy were collected from 14 rheumatology referral centers in Japan. A retrospective review of these patients and a case-control study to compare patients with and without PCP were performed. RESULTS: The median length of time from the first infliximab infusion to the development of PCP was 8.5 weeks. At the onset of PCP, the median dosages of prednisolone and methotrexate were 7.5 mg/day and 8 mg/week, respectively. Pneumocystis jiroveci was microscopically identified in only 2 patients, although the polymerase chain reaction test for the organism was positive in 20 patients. The patients with PCP had significantly lower serum albumin levels (P < 0.001) and lower serum IgG levels (P < 0.001) than the patients without PCP. Computed tomography of the chest in all patients with PCP revealed ground-glass opacity either with sharp demarcation by interlobular septa or without interlobular septal boundaries. Sixteen of the 21 patients with PCP developed acute respiratory failure, but all survived. CONCLUSION: PCP is a serious complication that may occur early in the course of infliximab therapy in patients with RA. For the proper clinical management of this infectious disease, physicians need to be aware of the possibility of PCP developing during infliximab therapy.

A case report of rheumatoid arthritis complicated with rapidly progressive interstitial pneumonia, multiple bullae and pneumomediastinum, which was successfully treated with tacrolimus.

A 64-year-old woman had been treated with prednisolone (PSL) for interstitial pneumonia (IP) of unknown origin since 1988. The IP progressed gradually, however, and home oxygen therapy was instituted in 1993. In 2002, persistent arthritis of the hands appeared and diagnosis of rheumatoid arthritis (RA) was finally established based on radiological and pathological findings. Salazosulfapyridine was given with only partial effect. On October 2002, she was hospitalized because of back pain followed by dyspnea. Chest X-ray revealed multiple giant bullae on bilateral upper lung fields, accompanied by deterioration of IP. Methyl-prednisolone pulse therapy followed by 30 mg/day of PSL was instituted and the bullae were diminished with gradual improvement of IP and synovitis. On the 55th hospital day, she complained of chest oppression, and chest X-ray revealed a complication of pneumomediastinum. Since IP was still active and serum KL-6 remained high, 3 mg/day of tacrolimus was added to control IP further and to reduce the dosage of PSL which was recognized as one of the aggravation factors of pneumomediastinum. As a result, pneumomediastinum disappeared gradually along with amelioration of IP. PSL was successfully tapered to 15 mg/day by the 87th hospital day and the patient was discharged. Although the efficacy of tacrolimus on IP complicated with polymyositis / dermatomyositis and other autoimmune diseases has been reported, this case first suggests its efficacy on IP associated with RA.

[A case of progressive multifocal leukoencephalopathy associated with systemic lupus erythematosus].

We describe a case of systemic lupus erythematosus (SLE) complicated with multifocal leukoencephalopathy (PML). A 57-year old woman, who had a five-year history of SLE, was admitted to our hospital because of fever and multiple subcutaneous nodules. Diagnosis of disseminated cryptococcosis was made based on histological and bacteriological examinations, and she was successfully treated with anti-fungal drugs. Corticoteroids were increased for persistent lupus activities. One month later, however, she gradually developed disorientation and short-term memory loss. A brain magnetic resonance image (MRI) showed a focal lesion in the white matter of the right frontal lobe. Brain biopsy demonstrated demyelinating lesions with the presence of JC viral antigen. Polymerase chain reaction also revealed JC virus DNA in the cerebrospinal fluid. Her condition gradually progressed, and she died a year later due to pneumonia. Although acquired immunodeficiency syndrome is currently the most common disease associated with PML, patients with autoimmune diseases receiving immunosuppressive therapy also have risks for developing PML. In patients with SLE presenting with subacute neurological abnormalities and white matter lesions in the brain, PML should be considered in the differential diagnosis.

NF-kappaB inhibitor dehydroxymethylepoxyquinomicin suppresses osteoclastogenesis and expression of NFATc1 in mouse arthritis without affecting expression of RANKL, osteoprotegerin or macrophage colony-stimulating factor.

Inhibition of NF-kappaB is known to be effective in reducing both inflammation and bone destruction in animal models of arthritis. Our previous study demonstrated that a small cell-permeable NF-kappaB inhibitor, dehydroxymethylepoxyquinomicin (DHMEQ), suppresses expression of proinflammatory cytokines and ameliorates mouse arthritis. It remained unclear, however, whether DHMEQ directly affects osteoclast precursor cells to suppress their differentiation to mature osteoclasts in vivo. The effect of DHMEQ on human osteoclastogenesis also remained elusive. In the present study, we therefore examined the effect of DHMEQ on osteoclastogenesis using a mouse collagen-induced arthritis model, and using culture systems of fibroblast-like synovial cells obtained from patients with rheumatoid arthritis, and of osteoclast precursor cells from peripheral blood of healthy volunteers. DHMEQ significantly suppressed formation of osteoclasts in arthritic joints, and also suppressed expression of NFATc1 along the inner surfaces of bone lacunae and the eroded bone surface, while serum levels of soluble receptor activator of NF-kappaB ligand (RANKL), osteoprotegerin and macrophage colony-stimulating factor were not affected by the treatment. DHMEQ also did not suppress spontaneous expression of RANKL nor of macrophage colony-stimulating factor in culture of fibroblast-like synovial cells obtained from patients with rheumatoid arthritis. These results suggest that DHMEQ suppresses osteoclastogenesis in vivo, through downregulation of NFATc1 expression, without significantly affecting expression of upstream molecules of the RANKL/receptor activator of NF-kappaB/osteoprotegerin cascade, at least in our experimental condition. Furthermore, in the presence of RANKL and macrophage colony-stimulating factor, differentiation and activation of human osteoclasts were also suppressed by DHMEQ, suggesting the possibility of future application of NF-kappaB inhibitors to rheumatoid arthritis therapy.