*Department of Pharmacy, Hirosaki University Hospital, Aomori, Japan;

†Department of Cardiology, Hirosaki University Graduate School of Medicine, Aomori, Japan; and

‡Department of Pharmaceutical Science, Hirosaki University Graduate School of Medicine, Aomori, Japan.

Correspondence: Takenori Niioka, PhD, Department of Pharmacy, Hirosaki University Hospital, 53 Hon-cho, Hirosaki, Aomori 036-8563, Japan (e-mail: [email protected]).

Conceptualization, T. Niioka; investigation, T. Niioka and N. Aiuchi; plasma concentration measurements, J. Nakagawa and K. Ueno; formal analysis, J. Nakagawa; writing—original draft preparation, J. Nakagawa; writing—review and editing, H. Tomita and T. Niioka All authors read and approved the final manuscript.

H. Tomita received research funding from Boehringer Ingelheim, Bayer, and Daiichi-Sankyo and speakers' bureau/honoraria from Bayer, Boehringer Ingelheim, Bristol-Myers Squibb, Daiichi-Sankyo, and Pfizer. T. Niioka received research funding and speakers' honoraria from Daiichi-Sankyo. The remaining authors declare no conflict of interest.

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