Footnotes

• Correction notice The article has been corrected since it was published Online First. The author list has been amended.

• Contributors HF designed the study, carried out genotyping and statistical analyses, and wrote the manuscript. SO carried out genotyping. HF, KS, ST and RA-ILD Study Consortium members recruited Japanese patients with RA and collected clinical information. NT and ST designed and coordinated the study and helped with manuscript preparation.

• Funding The work was supported by Grant-in-Aid for Scientific Research (B, C) (22390199, 22591090) from the Japan Society for the Promotion of Science; Health and Labour Science Research Grants from the Ministry of Health, Labour, and Welfare of Japan; Grants-in-Aid for Clinical Research from National Hospital Organization; Research Grants from Daiwa Securities Health Foundation; Research Grants from Japan Research Foundation for Clinical Pharmacology; Research Grants from The Nakatomi Foundation; Research Grants from Takeda Science Foundation; and research grants from pharmaceutical companies: Abbott Japan Co, Ltd; Astellas Pharma Inc; AstraZeneca KK; Bristol-Myers Squibb Co Ltd; Chugai Pharmaceutical Co, Ltd; Eisai Co, Ltd; Medical & Biological Laboratories Co, Ltd; Mitsuibishi Tanabe Pharma Corporation; Merck Sharp and Dohme Inc; Pfizer Japan Inc; Takeda Pharmaceutical Company Limited; and Teijin Pharma Limited. The funders had no role in study design, data collection and analysis, decision to publish, or preparing the manuscript.

• Competing interests HF has the following conflicts. The following funders are supported in whole or in part by the subsequent pharmaceutical companies. The Japan Research Foundation for Clinical Pharmacology is run by Daiichi Sankyo; the Takeda Science Foundation is supported by an endowment from Takeda Pharmaceutical Company; and the Nakatomi Foundation was established by Hisamitsu Pharmaceutical Co, Inc. The Daiwa Securities Health Foundation was established by Daiwa Securities Group Inc. ST was supported by research grants from pharmaceutical companies: Abbott Japan Co, Ltd, Astellas Pharma Inc, AstraZeneca KK, Bristol-Myers Squibb Co Ltd, Chugai Pharmaceutical Co, Ltd, Eisai Co, Ltd, Medical & Biological Laboratories Co, Ltd, Mitsuibishi Tanabe Pharma Corporation, Merck Sharp and Dohme Inc, Pfizer Japan Inc, Takeda Pharmaceutical Company Limited, and Teijin Pharma Limited. The other authors declare no financial or commercial conflict of interest.

• Patient consent Obtained.

• Ethics approval This study was reviewed and approved by the research ethics committees of each participating institute.

• Provenance and peer review Not commissioned; externally peer reviewed