*Department of Clinical Pharmacology, Faculty of Pharmaceutical Sciences, Hokkaido University of Science, Hokkaido, Japan;

†Department of Pharmacy, University of Tsukuba Hospital, Ibaraki, Japan;

‡Biotage Japan Ltd., Tokyo, Japan;

§Department of Hematology, Blood Disorders Center, Aiiku Hospital, Hokkaido, Japan;

¶Department of Pharmacotherapy, Faculty of Pharmaceutical Sciences, Hokkaido University of Science, Hokkaido, Japan;

‖Clinical Research Institute for Clinical Pharmacology and Therapeutics, Showa University, Tokyo, Japan; and

**Division of Practical Pharmacy, Nihon Pharmaceutical University, Saitama, Japan.

Correspondence: Takaki Toda, PhD, Department of Clinical Pharmacology, Faculty of Pharmaceutical Sciences, Hokkaido University of Science, Hokkaido 006-8585, Japan (e-mail: [email protected]).

The ISOLUTE SLE + cartridges used for sample purification during method development were provided by Biotage Japan Ltd. This work was supported by JSPS KAKENHI Grant Number JP18K14988.

T. Yoshida is an employee of Biotage Japan Ltd. The other authors do not have any conflicts of interest.

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