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Dive into the research topics where Masao Nawata is active.

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Featured researches published by Masao Nawata.


Annals of the Rheumatic Diseases | 2006

Efficacy of rituximab (anti-CD20) for refractory systemic lupus erythematosus involving the central nervous system

Mikiko Tokunaga; Kazuyoshi Saito; Daisuke Kawabata; Yoshitaka Imura; Shingo Nakayamada; Shizuyo Tsujimura; Masao Nawata; Shigeru Iwata; Taeko Azuma; Tsuneyo Mimori; Yoshiya Tanaka

Aim: Neuropsychiatric systemic lupus erythematosus (NPSLE) is a serious treatment-resistant phenotype of systemic lupus erythematosus. A standard treatment for NPSLE is not available. This report describes the clinical and laboratory tests of 10 patients with NPSLE before and after rituximab treatment, including changes in lymphocyte phenotypes. Methods: Rituximab was administered at different doses in 10 patients with refractory NPSLE, despite intensive treatment. Results: Treatment with rituximab resulted in rapid improvement of central nervous system-related manifestations, particularly acute confusional state. Rituximab also improved cognitive dysfunction, psychosis and seizure, and reduced the SLE Disease Activity Index Score at day 28 in all 10 patients. These effects lasted for >1 year in five patients. Flow cytometric analysis showed that rituximab down regulated CD40 and CD80 on B cells and CD40L, CD69 and inducible costimulator on CD4+ T cells. Conclusions: Rituximab rapidly improved refractory NPSLE, as evident by resolution of various clinical signs and symptoms and improvement of radiographic findings. The down regulation of functional molecules on B and T cells suggests that rituximab modulates the interaction of activated B and T cells through costimulatory molecules. These results warrant further analysis of rituximab as treatment for NPSLE.


Annals of the Rheumatic Diseases | 2010

Discontinuation of infliximab after attaining low disease activity in patients with rheumatoid arthritis: RRR (remission induction by Remicade in RA) study

Yoshiya Tanaka; Tsutomu Takeuchi; Tsuneyo Mimori; Keiko Saito; Masao Nawata; Hideto Kameda; Takaki Nojima; Nobuyuki Miyasaka; Takao Koike

Background Tumour necrosis factor (TNF) inhibitors enable tight control of disease activity in patients with rheumatoid arthritis (RA). Discontinuation of TNF inhibitors after acquisition of low disease activity (LDA) is important for safety and economic reasons. Objective To determine whether infliximab might be discontinued after achievement of LDA in patients with RA and to evaluate progression of articular destruction during the discontinuation. Methods 114 patients with RA who had received infliximab treatment, and whose Disease Activity Score, including a 28-joint count (DAS28) was <3.2 (LDA) for 24 weeks, were studied. Results The mean disease duration of the 114 patients was 5.9 years, mean DAS28 5.5 and mean modified total Sharp score (mTSS) 63.3. After maintaining LDA for >24 weeks by infliximab treatment, the drug was discontinued and DAS28 in 102 patients was evaluated at year 1. Fifty-six patients (55%) continued to have DAS28<3.2 and 43% reached DAS<2.6 at 1 year after discontinuing infliximab. For 46 patients remission induction by Remicade in RA (RRR) failed: disease in 29 patients flared within 1 year and DAS28 was >3.2 at year 1 in 17 patients. Yearly progression of mTSS (ΔTSS) remained <0.5 in 67% and 44% of the RRR-achieved and RRR-failed groups, respectively. The estimated ΔmTSS was 0.3 and 1.6 and Health Assessment Questionnaire-Disability Index was 0.174 and 0.614 in the RRR-achieved and RRR-failed groups, respectively, 1 year after the discontinuation. Conclusion After attaining LDA by infliximab, 56 (55%) of the 102 patients with RA were able to discontinue infliximab for >1 year without progression of radiological articular destruction.


Rheumatology | 2011

Clinical, radiographic and functional effectiveness of tocilizumab for rheumatoid arthritis patients—REACTION 52-week study

Tsutomu Takeuchi; Yoshiya Tanaka; Koichi Amano; Daisuke Hoshi; Masao Nawata; Hayato Nagasawa; Eri Sato; Kazuyoshi Saito; Yuko Kaneko; Shunsuke Fukuyo; Takahiko Kurasawa; Kentaro Hanami; Hideto Kameda; Hisashi Yamanaka

Objectives. To evaluate the effectiveness and safety of tocilizumab in RA patients in clinical practice. Methods. We observed 232 consecutive RA patients who began tocilizumab in three rheumatology centres in Japan for 52 weeks. Clinical, radiographic and functional status and safety were evaluated. Results. Mean age of the 232 patients was 59.1 years, mean duration of disease was 12.4 years and average DAS using the 28-joint count (DAS-28) was 5.6. Although 62.8% of the patients had been treated previously with anti-TNF biologics, clinical remission at Week 52 was achieved in 43.7%, radiographic non-progression in 62.8% and functional remission in 26.4%. Retention rate at Week 52 was 71.1%, and the same for those with or without previous anti-TNF treatment. Adverse drug reactions leading to tocilizumab discontinuation were observed in 15.5% of patients, the most frequent adverse drug reaction being pneumonia in eight cases. On multivariate logistic regression analysis, DAS-28, HAQ-disability index (HAQ-DI), concomitant MTX and concomitant glucocorticoids (GCs) were predictive variables for clinical remission at Week 52 of tocilizumab treatment. In particular, HAQ-DI was found to be a predictive variable for remission of all three types—clinical, radiographic and functional—at Week 52 of tocilizumab treatment. Conclusions. In daily clinical practice, tocilizumab exhibited excellent effectiveness in established RA patients, some of whom had failed to respond to previous anti-TNF treatment. Although further detailed safety findings are required, this study provides valuable real-world findings on the management of RA with tocilizumab.


The Journal of Rheumatology | 2011

Phenotypic changes of lymphocytes in patients with systemic lupus erythematosus who are in longterm remission after B cell depletion therapy with rituximab

Shigeru Iwata; Kazuyoshi Saito; Mikiko Tokunaga; Kunihiro Yamaoka; Masao Nawata; Sonosuke Yukawa; Kentaro Hanami; Shunsuke Fukuyo; Ippei Miyagawa; Satoshi Kubo; Yoshiya Tanaka

Objective. Rituximab has recently emerged as a novel treatment strategy for systemic lupus erythematosus (SLE). We investigated longitudinally the differentiation and phenotypic changes of peripheral B cells and T cells in patients with SLE after rituximab treatment. Methods. Phenotypic changes on B cells and T cells in 10 patients with SLE treated with rituximab were analyzed before, 28 days after, and 2 years after rituximab treatment, and at relapse. Results. Rituximab rapidly depleted naive and memory B cells from the peripheral blood. In the patients with prolonged remission, the memory B cells remained depleted while naive B cells recovered within 3–9 months, and the expression levels of CD40 and CD80 remained downregulated for 2 years. There was also a decrease of memory T cells relative to naive T cells, and the expression of CD40L and inducible costimulator (ICOS) on CD4-positive T cells rapidly decreased and remained downregulated for 2 years. In 1 patient, an increase in the number of memory B cells with upregulation of CD40 and CD80 expression was noted just before relapse. In another patient with relapse, however, recovery of CD4-positive memory T cells with upregulation of ICOS expression was noted, with no change in the number of memory B cells. Conclusion. Our results suggest that the phenotypic changes of peripheral B cells result in inhibition of T cell differentiation and activation mediated by B cells and thereby bring about longterm remission of SLE. Activated memory B cells or ICOS-positive CD4-positive memory T cells reappeared in association with relapse, probably reflecting the heterogeneity of SLE.


The Journal of Rheumatology | 2010

Tacrolimus, a Calcineurin Inhibitor, Overcomes Treatment Unresponsiveness Mediated by P-glycoprotein on Lymphocytes in Refractory Rheumatoid Arthritis

Katsunori Suzuki; Kazuyoshi Saito; Shizuyo Tsujimura; Shingo Nakayamada; Kunihiro Yamaoka; Norifumi Sawamukai; Shigeru Iwata; Masao Nawata; Kazuhisa Nakano; Yoshiya Tanaka

Objective. Tacrolimus, a calcineurin inhibitor, is used for treatment of rheumatoid arthritis (RA). It also inhibits functions of P-glycoprotein, which is involved in drug resistance. We examined the mechanisms of early response to 2-week tacrolimus treatment in patients with RA. Methods. One hundred thirteen patients with refractory RA despite at least 3 antirheumatic agents, including methotrexate, were treated with tacrolimus (1.5–3 mg/day) and the response was assessed at 2 weeks. Expression of the multidrug resistance (MDR-1) gene and P-glycoprotein was assessed in peripheral blood mononuclear cells (PBMC) collected from 113 patients and 40 healthy subjects. The drug exclusion function by the P-glycoprotein was measured by the residual amount of intracellular tritium-labeled dexamethasone cell/medium ratio (C/M ratio). Results. The disease activity of enrolled patients was 5.8 ± 1.2 (mean ± SD) by DAS28 erythrocyte sedimentation rate. A good response to tacrolimus was noted at 2 weeks in 22 of 113 patients. At baseline, PBMC of patients with RA showed upregulated expression of MDR-1 gene and P-glycoprotein and low C/M ratio. The response to tacrolimus correlated with P-glycoprotein expression and C/M ratio. A significant improvement in C/M ratio was noted after 2 weeks of treatment. The C/M ratio correlated significantly with P-glycoprotein expression on CD4+ lymphocytes. Conclusion. Early efficacy of tacrolimus treatment depended on its inhibitory effect on the drug exclusion function of P-glycoprotein, leading to restoration of intracellular therapeutic levels of corticosteroids and clinical improvement. Evaluation of P-glycoprotein expression on lymphocytes is potentially useful for predicting the response to RA treatment.


The Journal of Rheumatology | 2008

Alendronate Protects Premenopausal Women from Bone Loss and Fracture Associated with High-dose Glucocorticoid Therapy

Yosuke Okada; Masao Nawata; Shingo Nakayamada; Kazuyoshi Saito; Yoshiya Tanaka

Objective We assessed the efficacy of bisphosphonate in premenopausal women (n = 47) commencing high-dose glucocorticoid (GC) therapy in protection against induced bone loss and bone fracture. Methods Subjects had just developed systemic autoimmune diseases and were randomized to be treated with 1 mg/kg/day prednisolone and alfacalcidol 1 μg/day alone (alfacalcidol group; n = 22), or prednisolone and alfacalcidol 1 μg/day with alendronate 5 mg/day (alendronate group; n = 25), each for 18 months. Results The percentage changes in lumbar spine bone mineral density (BMD) after 6 months of the therapy were −10.5% ± 0.8% in the alfacalcidol group, but only −2.1% ± 1.2% in the combined group. The rate of bone loss in the lumbar spine was significantly lower in the combined group than in the alfacalcidol group at 6 months. At 12 months of treatment, the percentage change in lumbar spine BMD was increased by 1.7% ± 1.4% in the combined group, but decreased by 9.9% ± 1.9% in the alfacalcidol group; the difference was significant. Bone fracture occurred at 12 months or later in 4 patients of the alfacalcidol groups, but not in the combined group, even at up to 18 months. Conclusion Our results indicate that alendronate with alfacalcidol can maintain BMD and protects against high-dose GC-induced bone loss and bone fracture.


Modern Rheumatology | 2014

Study on the safety and efficacy of tocilizumab, an anti-IL-6 receptor antibody, in patients with rheumatoid arthritis complicated with AA amyloidosis

Ippei Miyagawa; Shingo Nakayamada; Kazuyoshi Saito; Kentaro Hanami; Masao Nawata; Norifumi Sawamukai; Kazuhisa Nakano; Kunihiro Yamaoka; Yoshiya Tanaka

Abstract Objectives: Although treatment of rheumatoid arthritis (RA) has progressed by the use of biologics, amyloid A (AA) amyloidosis is still an intractable complication in patients with RA. In the present study, safety and efficacy of 1-year treatment with an anti-IL-6 receptor antibody tocilizumab (TCZ) on RA and AA amyloidosis were estimated. Methods: TCZ (8 mg/kg every 4 weeks) was administered to five RA patients complicated with AA amyloidosis. The primary end point was improvement in renal dysfunction and the secondary end point was CDAI at 1 year after the treatment. Results: An improvement in the renal dysfunction, including urinary protein secretion, was found, in four patients including two patients who were refractory to etanercept, with a remarkable decrease of SAA concentration, and the progression of organ dysfunction was prevented at 1 year in all patients treated with TCZ. The mean clinical disease activity index decreased from 33.9 to 4.7 (p = 0.012) in five patients treated with TCZ for 1 year. Three non-serious adverse events were observed in two patients. Conclusions: TCZ ameliorates renal dysfunction in RA patients complicated with AA amyloidosis who are refractory to conventional therapies, thereby suggesting that TCZ has a potential to regulate AA amyloidosis.


Arthritis Research & Therapy | 2013

Discontinuation of adalimumab after attaining disease activity score 28-erythrocyte sedimentation rate remission in patients with rheumatoid arthritis (HONOR study): an observational study

Shintaro Hirata; Kazuyoshi Saito; Satoshi Kubo; Shunsuke Fukuyo; Yasushi Mizuno; Shigeru Iwata; Masao Nawata; Norifumi Sawamukai; Kazuhisa Nakano; Kunihiro Yamaoka; Yoshiya Tanaka

IntroductionEvidences of biologics-free disease control after discontinuing adalimumab (ADA) in rheumatoid arthritis (RA) patients in clinical practice have not been sufficiently investigated. Purpose of this study is to investigate whether disease activity score 28 (DAS28)- erythrocyte sedimentation rate (ESR) remission was preserved after discontinuation of ADA in patients with RA.MethodsThis is an observational but not a randomized controlled study. Among 197 RA patients who initiated with combination of ADA with concomitant MTX, 69 (35%) acquired DAS28 (ESR) < 2.6 for at least 24 weeks. Of those 69 patients, 51 went on ADA discontinuation with their consent, and finally 50 of those with follow-up of > 24 weeks were evaluated. The effect of discontinuing ADA on clinical disease activity, functional disability and radiographic progression were evaluated by DAS28 (ESR), the clinical disease activity index (CDAI) and the simplified disease activity index (SDAI), by a health assessment questionnaire-disability index (HAQ-DI) and by the modified total Sharp score (mTSS), respectively.ResultsThe mean age of the participants was 59.5 years with the mean disease duration of 7.1 years. Out of the 50 patients, 29 (58%) were maintained in DAS28 (ESR) < 2.6 at 24 weeks after discontinuing ADA. A logistic regression analysis showed that DAS28 (ESR) at baseline significantly predicted a DAS28 (ESR) < 2.6 maintained after discontinuation of ADA, and a receiver-operating characteristic (ROC) analysis showed that the cut-off value of DAS28 (ESR) at discontinuation was 2.16. The mean HAQ-DI at six months after discontinuing ADA was 0.1 in patients who kept in DAS28 (ESR) < 2.6, and 94.9% (37/39) showed no evidence of radiographic progression (> 0.5 per year of a change in mTSS) at 1 year.ConclusionsIt was possible to maintain DAS28 (ESR) < 2.6 after discontinuation of ADA without functional and radiographic progression and very low DAS28 (ESR) at the discontinuation was associated with successful ADA-free DAS28 (ESR) < 2.6 in patients with RA.Trial registrationUniversity Hospital Medical Information Network Identifier: UMIN000006669.


Modern Rheumatology | 2014

Effect of interleukin-6 receptor inhibitor, tocilizumab, in preventing joint destruction in patients with rheumatoid arthritis showing inadequate response to TNF inhibitors

Yoshiya Tanaka; Tsutomu Takeuchi; Koichi Amano; Kazuyoshi Saito; Kentaro Hanami; Masao Nawata; Shunsuke Fukuyo; Hideto Kameda; Yuko Kaneko; Takahiko Kurasawa; Hayato Nagasawa; Daisuke Hoshi; Eri Sato; Hisashi Yamanaka

Abstract Objectives. To examine the effectiveness of tocilizumab (TCZ) in preventing joint destruction in patients with inadequate response to tumor necrosis factor inhibitors (TNF-IR) by assessing X-rays. Methods. RA patients were extracted from the Retrospective actemra investigation for optimal needs of RA patients (REACTION) study. Parameters and components of disease activity were evaluated during anti-TNF treatment and during TCZ treatment. X-ray images of hands and feet at the beginning of this study during anti-TNF treatment (Pre), at the start point of TCZ treatment (Baseline) and after TCZ treatment (Post) were collected for assessing joint destruction. Results. Forty-five patients from the REACTION study fulfilled the criteria of clinical TNF-IR. During anti-TNF treatment, mean DAS28-ESR rose from 5.35 to 5.87 (mean observation duration, 16 months) but improved significantly to 2.94 (P < 0.0001) at 52 weeks after switching to TCZ. Mean change in van der Heijde-modified Sharp score (TSS) during anti-TNF treatment was 3.17 in this TNF-IR population. After switching to TCZ, mean change in TSS was 1.20 (P < 0.05). Rate of radiographic non-progression improved to 66.7% during TCZ treatment from 40.0% during anti-TNF treatment. The predictive factor for no radiographic progression after switching to TCZ was a HAQ disability index (HAQ-DI) score of ≤ 1.88 at switching to TCZ. Conclusion. TCZ was a good treatment option for improving signs and symptoms and inhibiting progression of joint damage in patients with clinical and structural TNF-IR.


Modern Rheumatology | 2003

Efficacy of mizoribine treatment in patients with SjÖgren’s syndrome: an open pilot trial

Shingo Nakayamada; Kazuyoshi Saito; Keisuke Nakatsuka; Kazuhisa Nakano; Mikiko Tokunaga; Norifumi Sawamukai; Shizuyo Tsujimura; Masao Nawata; Yoshiya Tanaka

Abstract The aim of this study was to evaluate the efficacy and safety of mizoribine in patients with Sjögren’s syndrome. Forty patients with sicca syndrome, whose conditions were definitely diagnosed as Sjögren’s syndrome, were given mizoribine orally at a dosage of 150 mg/day for 12 months. The percentage change in salivary secretion after 3, 6, and 12 months of the therapy increased to +112.2% (P < 0.001), +119.9% (P < 0.01), and +147.3% (P < 0.001), respectively, compared with the baseline. Serum IgG levels decreased significantly throughout the study, and the level was 1969.4 ± 620.0 mg/dl after treatment for 12 months compared with the pretreatment value of 2094.3 ± 746.6 mg/dl (P < 0.05). The patient’s assessment of clinical signs and symptoms on a 10-cm visual analog scale improved significantly from 7.2 ± 2.3 cm at the start of the treatment to 5.0 ± 1.9 cm after 12 months (P < 0.001). There was a similar improvement in the physician’s assessment using the 10-cm visual analog scale: 7.1 ± 1.6 cm at the start of the treatment and 5.2 ± 1.9 cm after 12 months (P < 0.001). With regard to safety, no serious adverse reactions were observed. Although a controlled study would be required to clarify the efficacy of mizoribine, these preliminary observations indicate its efficacy for ameliorating glandular symptoms through improvements in immune abnormalities in patients with Sjögren’s syndrome.

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Yoshiya Tanaka

University of Occupational and Environmental Health Japan

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Kazuyoshi Saito

University of Occupational and Environmental Health Japan

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Shigeru Iwata

University of Occupational and Environmental Health Japan

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Kunihiro Yamaoka

University of Occupational and Environmental Health Japan

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Shingo Nakayamada

University of Occupational and Environmental Health Japan

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Kentaro Hanami

University of Occupational and Environmental Health Japan

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Shunsuke Fukuyo

University of Occupational and Environmental Health Japan

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Shizuyo Tsujimura

University of Occupational and Environmental Health Japan

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Hisashi Yamanaka

Saitama Medical University

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