Jun Ishizaki, Ayako Takemori, Kenta Horie, Daisuke Hiraoka, Koichiro Suemori, Takuya Matsumoto, Ken ei Sada, Koichi Amano, Masayoshi Harigai, Yoshihiro Arimura, Hirofumi Makino, Katsuto Takenaka, Nobuaki Takemori, Hitoshi Hasegawa, Yohko Murakawa, Eri Muso, Atsushi Komatsuda, Satoshi Ito, Takao Fujii, Atsushi Kawakami, Izaya Nakaya, Takao Saito, Takafumi Ito, Nobuhito Hirawa, Masahiro Yamamura, Masaaki Nakano, Kosaku Nitta, Makoto Ogura, Taio Naniwa, Shoichi Ozaki, Junichi Hirahashi, Noriyoshi Ogawa, Tatsuo Hosoya, Takashi Wada, Satoshi Horikoshi, Yasushi Kawaguchi, Taichi Hayashi, Masaharu Yoshida, Tsuyoshi Watanabe, Daijo Inaguma, Kazuhiko Tsuruya, Noriyuki Homma, Tsutomu Takeuchi, Naoki Nakagawa, Shinichi Takeda, Ritsuko Katabuchi, Masayuki Iwano, Tatsuya Atsumi, Shoichi Fujimoto, Shogo Banno, Takahiko Sugihara, Masaki Kobayashi, Kunihiro Yamagata, Sakae Homma, Hiroaki Dobashi, Naotake Tsuboi, Akihiro Ishizu, Hitoshi Sugiyama
Arthritis Research and Therapy 23(1) 2021年12月
Background: We previously identified tissue inhibitor of metalloproteinase 1 (TIMP-1) as a biomarker of disease activity that distinguished mildly or highly active antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV) from remission 6 months after the initiation of remission-induction therapy. In the present study, we investigated whether TIMP-1 is clinically useful as a predictor of relapse and sustained remission in AAV patients with microscopic polyangiitis (MPA) and granulomatosis with polyangiitis (GPA) during maintenance therapy. Methods: The relationship between serum TIMP-1 levels and clinical outcomes in AAV patients receiving maintenance therapy was assessed using the follow-up data of a Japanese large-cohort study (the RemIT-JAV-RPGN study) and data collected from AAV patients on maintenance therapy in our hospital (the MAAV-EU study). Results: In the RemIT-JAV RPGN study, serum levels of TIMP-1 were significantly higher in mildly active AAV patients with MPA and GPA 6 months after the initiation of remission-induction therapy than in patients in remission. Regarding maintenance therapy, elevated levels of TIMP-1 in patients in remission were associated with relapse and/or difficulty reducing the glucocorticoid dosage after 6 to 12 months. In the MAAV-EU study, serum levels of TIMP-1 were elevated in relapsed patients 6 months before relapse, earlier than the increase in serum levels of CRP. Analyses of both studies revealed that approximately 30% of patients in remission with a serum TIMP-1 level ≥ 150 ng/mL relapsed after 6 to 12 months, while the majority of patients with a TIMP-1 level < 150 ng/mL sustained remission for at least 12 months. Conclusion: We herein demonstrated that TIMP-1 is more useful as a predictive biomarker of sustained remission than as a predictor of relapse in maintenance therapy for AAV. TIMP-1 levels < 150 ng/mL are important for the long-term maintenance of remission and may be an indicator for the tapering or cessation of treatment.