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Dive into the research topics where Masakazu Kondo is active.

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Featured researches published by Masakazu Kondo.


Arthritis Care and Research | 2014

Phase III Study of the Efficacy and Safety of Subcutaneous Versus Intravenous Tocilizumab Monotherapy in Patients With Rheumatoid Arthritis

Atsushi Ogata; Kazuhide Tanimura; Toyohiko Sugimoto; Hiroshi Inoue; Yukitomo Urata; Tsukasa Matsubara; Masakazu Kondo; Yukitaka Ueki; Mitsuhiro Iwahashi; Shigeto Tohma; Shuji Ohta; Yukihiko Saeki; Toshio Tanaka

To evaluate the efficacious noninferiority of subcutaneous tocilizumab injection (TCZ‐SC) monotherapy to intravenous TCZ infusion (TCZ‐IV) monotherapy in Japanese patients with rheumatoid arthritis (RA) with an inadequate response to synthetic and/or biologic disease‐modifying antirheumatic drugs (DMARDs).


Modern Rheumatology | 2014

Safety and efficacy of combination therapy of iguratimod with methotrexate for patients with active rheumatoid arthritis with an inadequate response to methotrexate: An open-label extension of a randomized, double-blind, placebo-controlled trial

Masako Hara; Naoki Ishiguro; Kou Katayama; Masakazu Kondo; Takayuki Sumida; Tsuneyo Mimori; Satoshi Soen; Kota Nagai; Tomonobu Yamaguchi; Kazuhiko Yamamoto

Abstract Objective. To obtain safety and efficacy data on combination treatment with iguratimod and methotrexate (MTX) in an open-label extension study in patients with active rheumatoid arthritis (RA). Methods. Following a 28-week, randomized, double-blind trial of adding iguratimod or placebo to stable MTX therapy, patients entered a 24-week extension. Patients randomized to the iguratimod + MTX group continued treatment. Patients treated with placebo + MTX switched to iguratimod + MTX [the (placebo/iguratimod) + MTX group]. Results. In the iguratimod + MTX group, the rate of 20% improvement in American College of Rheumatology criteria (ACR20) at week 52 (71.3%) was similar to that at week 24 (69.5%). ACR50, ACR70 and Health Assessment Questionnaire Disability Index at week 52 significantly improved compared with the values at week 24. In the (placebo/iguratimod + MTX) group, the switch to iguratimod treatment significantly improved ACR20 from 30.7% at week 24 to 72.1% at week 52. Frequent adverse events for 52 weeks in the iguratimod + MTX group were nasopharyngitis, upper respiratory tract inflammation, stomatitis, lymphocyte decrease, AST increase, ALT increase and blood iron decrease. These adverse events were predominantly mild or moderate in severity. No deaths occurred. Conclusion. Efficacy and tolerance of iguratimod + MTX therapy was maintained to 52 weeks in patients with active RA with inadequate response to MTX.


Drug Design Development and Therapy | 2014

Drug delivery options to increase patient adherence and satisfaction in the management of rheumatoid arthritis - focus on subcutaneous tocilizumab

Yasuharu Nakashima; Masakazu Kondo; Hisaaki Miyahara; Yukihide Iwamoto

Rheumatoid arthritis (RA) is a chronic, progressive, inflammatory disease associated with joint destruction. Tocilizumab (TCZ) is a humanized monoclonal anti-interleukin-6 receptor antibody that was initially developed for use as an intravenous (IV) infusion. Previous studies have shown that TCZ-IV is an important treatment option in patients with moderate-to-severe RA. A subcutaneous (SC) formulation of 162 mg TCZ that was recently developed and approved provides an additional treatment option for RA patients. In the present review, we provide an update on the efficacy and safety of TCZ-SC, compared with TCZ-IV. The TCZ-SC doses of 162 mg every 2 weeks (q2w) or weekly (qw) were selected based on pharmacokinetic and pharmacodynamic studies. Both TCZ-SC q2w and qw regimens showed equivalent effects to TCZ-IV in most patients; however, the TCZ-SC qw regimen consistently showed a more rapid effect in terms of C-reactive protein normalization. Randomized controlled studies showed that TCZ-SC monotherapy or combined with disease-modifying antirheumatic drugs demonstrated comparable efficacy to TCZ-IV in patients who were both biologic-naïve and refractory to tumor necrosis factor inhibitors. TCZ-SC at both qw and q2w were generally well-tolerated for up to 24 weeks. There was a low rate of withdrawal due to adverse events, and their incidence was comparable with that seen with TCZ-IV. An injection site reaction was seen in approximately 10% of patients who received the subcutaneous formulation. In conclusion, although clinical results are still limited, the currently available evidence suggests that TCZ-SC is a promising treatment for moderate-to-severe RA, both as monotherapy and combination therapy. More data is needed to determine the optimal dosing schedule.


Modern Rheumatology | 2017

Impact of methotrexate dose on efficacy of adalimumab in Japanese patients with rheumatoid arthritis: Results from registered data analyses

Yasuharu Nakashima; Hisaaki Miyahara; Masakazu Kondo; Takaaki Fukuda; Hiroshi Harada; Akihisa Haraguchi; Yasushi Inoue; Takashi Ishinishi; Masayuki Maekawa; Akira Maeyama; Munetoshi Nakashima; Eisuke Shono; Eiichi Suematsu; Takashi Shimauchi; Tomomi Tsuru; Hiroshi Tsukamoto; Shigeru Yoshizawa; Seiji Yoshizawa; Yukihide Iwamoto

Abstract Objective: Upper limit of methotrexate (MTX) for patients with rheumatoid arthritis (RA) was recently increased from 8 to 16 mg/week in Japan. We therefore examined the effect of concomitant MTX dose on the efficacy of adalimumab (ADA) in clinical practice. Method: Sixty-one consecutive RA patients treated with ADA were followed for minimum 52 weeks and retrospectively compared by MTX dose; patients receiving concomitant MTX of 10 mg/week or more (MTX ≥10 mg group) and <10 mg/week (MTX <10 mg group). Disease activity and remission were evaluated by the disease activity score 28 (DAS28) criteria. Results: The MTX ≥10 mg group consistently showed better improvement in DAS28 and resulted in more patients (52.8%) with DAS28-remission compared with the MTX <10 mg group (26.1%). Multivariate analysis showed that MTX ≥10 mg had a significant effect on DAS28 remission with odds ratio of 5.12. ADA retention rate was 72.2% in MTX ≥10 mg group compared with 52.0% in MTX <10 mg group. Discontinuation of ADA due to adverse events were comparable in the MTX ≥10 mg and MTX <10 mg groups (11.1% vs. 12.0%). Conclusions: These findings support the critical role of concomitant MTX in the efficacy of ADA, and recommend use of MTX ≥10 mg in Japanese RA patients.


Modern Rheumatology | 2016

The usefulness of a new triple combination treatment utilizing methotrexate, salazosulfapyridine, and bucillamine in rheumatoid arthritis.

Hiroaki Matsuno; Masato Okada; Yoshitada Sakai; Chiyuki Abe; Kou Katayama; Akira Sagawa; Kuniomi Yamasaki; Masakazu Kondo; Keiko Funahashi; Tsukasa Matsubara

Objectives. Combination treatment with methotrexate, salazosulfapyridine and bucillamine as an alternative to treatment with TNF-inhibiting biologics in rheumatoid arthritis was investigated. Methods. Twenty-six facilities allied with the Japan Association of Rheumatologists in Private Practice participated in this study. One hundred and twelve patients enrolled in this study, all of whom were within 3 years of diagnosis with rheumatoid arthritis for whom treatment with one DMARD or a combination of two DMARDs had failed (DAS28 > 3.2). Patients chose their own treatment. The triple DMARDs combination group was comprised of 72 patients; the TNF-inhibiting biologics treatment group was comprised of 40 patients. Results. DAS28 scores for the triple DMARDs combination group and the TNF-inhibiting biologics treatment groups were 4.84 ± 0.96 and 5.23 ± 1.26, and there was no significant difference between the two groups. From the 6th month, average disease activities of both groups were reduced, and there was no difference between the two groups at 12 months (DAS28, 3.39 ± 1.43 and 3.05 ± 1.43, p = 0.39). Furthermore, there was no significant difference in the degree of bone destruction between the two groups at 12 months. Conclusions. The triple DMARD combination therapy provided a new treatment option for those patients for whom treatment with biologics is difficult.


Journal of Orthopaedic Surgery and Research | 2014

Characteristics of lumbar scoliosis in patients with rheumatoid arthritis

Masanobu Ohishi; Hisaaki Miyahara; Masakazu Kondo; Yasuharu Nakashima; Kazumasa Terada; Yukio Esaki; Nobuo Kobara; Katsumi Harimaya; Yoshihiro Matsumoto; Yukihide Iwamoto

BackgroundAlthough a substantial percentage of patients with rheumatoid arthritis (RA) experience low back pain, the characteristics of lumbar spine pathology in RA patients has been poorly investigated. In our institutions, lumbar spine radiographs indicated scoliosis in 26 patients. The present study aimed to clarify the characteristics of lumbar scoliosis in RA patients.MethodsThis is a retrospective study of 26 RA patients with lumbar scoliosis. Patient characteristics such as disease duration, disease stage and class according to Steinbrockers classification, and medication for RA and osteoporosis were reviewed. Radiologic evaluation of scoliosis was performed at two different time points by measuring Cobb angles. The progression of scoliosis per year was calculated by dividing the change in Cobb angles by the number of years. Apical vertebral rotation, lateral listhesis, and the level of the intercrestal line at the first observation were also measured. The correlation between different factors and changes in the Cobb angles per year was analyzed.ResultsMajority of the patients had a long disease duration and were classified as stage 3 or 4 according to Steinbrockers classification. During the observation period, most patients were treated with glucocorticoids. Unlike the previous studies on degenerative scoliosis, apical vertebral rotation, lateral listhesis, and the level of the intercrestal line at initial observation were not significantly related to the progression of scoliosis. Initial Cobb angles were inversely related to the progression of scoliosis. Patients who were treated with bisphosphonates showed slower progression of scoliosis.ConclusionsOur results indicate that the characteristics of lumbar scoliosis in RA patients differ from those of degenerative lumbar scoliosis. Bone fragility due to the long disease duration, poor control of disease activity, and osteoporosis is possibly related to its progression.


Modern Rheumatology | 2013

Drug free REmission/low disease activity after cessation of tocilizumab (Actemra) Monotherapy (DREAM) study

Norihiro Nishimoto; Koichi Amano; Yasuhiko Hirabayashi; Takahiko Horiuchi; Tomonori Ishii; Mitsuhiro Iwahashi; Masahiro Iwamoto; Hitoshi Kohsaka; Masakazu Kondo; Tsukasa Matsubara; Toshihide Mimura; Hisaaki Miyahara; Shuji Ohta; Yukihiko Saeki; Kazuyoshi Saito; Hajime Sano; Kiyoshi Takasugi; Tsutomu Takeuchi; Shigeto Tohma; Tomomi Tsuru; Yukitaka Ueki; Jiro Yamana; Jun Hashimoto; Takaji Matsutani; M. Murakami; Nobuhiro Takagi


Modern Rheumatology | 2010

Clinical evaluation of tocilizumab for patients with active rheumatoid arthritis refractory to anti-TNF biologics: tocilizumab in combination with methotrexate

Yasuharu Nakashima; Masakazu Kondo; Hiroshi Harada; Takahiko Horiuchi; Takashi Ishinishi; Hiroshi Jojima; Koji Kuroda; Hisaaki Miyahara; Ryuji Nagamine; Hitoshi Nakashima; Takeshi Otsuka; Isao Saikawa; Eisuke Shono; Eiichi Suematsu; Tomomi Tsuru; Ken Wada; Yukihide Iwamoto


Modern Rheumatology | 2013

Concomitant iguratimod therapy in patients with active rheumatoid arthritis despite stable doses of methotrexate: a randomized, double-blind, placebo-controlled trial

Naoki Ishiguro; Kazuhiko Yamamoto; Kou Katayama; Masakazu Kondo; Takayuki Sumida; Tsuneyo Mimori; Satoshi Soen; Kota Nagai; Tomonobu Yamaguchi; Masako Hara


Modern Rheumatology | 2007

Enhanced effect of high-dose leukocytapheresis using a large filter in rheumatoid arthritis

Katsumi Eguchi; Kazuyoshi Saito; Masakazu Kondo; Toshihiko Hidaka; Yukitaka Ueki; Yoshiya Tanaka

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Kazuyoshi Saito

University of Occupational and Environmental Health Japan

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Kou Katayama

Asahikawa Medical College

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