著者
Miyako Yoshida Honami Kojima Atsushi Uda Tamami Haraguchi Minoru Ozeki Ikuo Kawasaki Kazuhiro Yamamoto Ikuko Yano Midori Hirai Takahiro Uchida
出版者
The Pharmaceutical Society of Japan
雑誌
Chemical and Pharmaceutical Bulletin (ISSN:00092363)
巻号頁・発行日
vol.67, no.5, pp.404-409, 2019-05-01 (Released:2019-05-01)
参考文献数
30
被引用文献数
9 9

The purpose of the study was to evaluate the ability of different beverages to mask the bitterness of zopiclone and eszopiclone in tablet formulations using the artificial taste sensor and human gustatory sensation testing. The beverages tested for bitterness-masking effects were: Mugicha, Sports beverage, Lactic acid drink, Orange juice and a diluted simple syrup (an 8.5% sucrose solution). The bitterness intensities estimated by the taste sensor of zopiclone or eszopiclone one-tablet solutions mixed with the various beverages, corresponded well with the observed bitterness intensities measured by gustatory sensation testing. The Sports beverage, Lactic acid drink and Orange juice significantly suppressed the bitterness intensity of both zopiclone and eszopiclone 1-tablet solutions compared with water when tested in the artificial taste sensor. Sports beverage, Lactic acid drink and Orange juice all contain citric acid as acidifier, so it was postulated that citric acid was involved in the mechanism of bitterness intensity suppression of zopiclone and eszopiclone 1-tablet solutions by these three beverages. It was then shown that citric acid suppressed the bitterness intensity of a zopiclone one-tablet sample solution in a dose-dependent manner. 1H-NMR spectroscopic analysis of mixtures of citric acid with zopiclone suggested that the carboxyl groups of citric acid interact with the amine group on zopiclone. This study therefore showed that the bitterness intensities of zopiclone and eszopiclone can be suppressed by citric-acid-contained beverages and suggests that this bitterness suppression is due to a direct electrostatic interaction between citric acid and the two drugs.
著者
Yuya Matsuda Shunsaku Nakagawa Ikuko Yano Satohiro Masuda Satoshi Imai Atsushi Yonezawa Takashi Yamamoto Mitsuhiro Sugimoto Masahiro Tsuda Tetsunori Tsuzuki Tomohiro Omura Takayuki Nakagawa Toyofumi Fengshi Chen-Yoshikawa Miki Nagao Hiroshi Date Kazuo Matsubara
出版者
The Pharmaceutical Society of Japan
雑誌
Biological and Pharmaceutical Bulletin (ISSN:09186158)
巻号頁・発行日
vol.45, no.4, pp.397-402, 2022-04-01 (Released:2022-04-01)
参考文献数
24
被引用文献数
3

Invasive Aspergillus infection is a major factor for poor prognosis in patients receiving lung transplantation (LT). An antifungal agent, itraconazole (ITCZ), that has antimicrobial activity against Aspergillus species, is used as a prophylactic agent against Aspergillus infection after LT. ITCZ and its metabolite, hydroxyitraconazole (OH-ITCZ), potently inhibit CYP3A and P-glycoprotein that metabolize or excrete calcineurin inhibitors (CNIs), which are the first-line immunosuppressants used after LT; thus, concomitant use of ITCZ and CNIs could induce an increase in the blood concentration of CNIs. However, no criteria for dose reduction of CNIs upon concomitant use with ITCZ in LT recipients have been defined. In this study, the effect of ITCZ and OH-ITCZ on the blood concentrations of two CNIs, tacrolimus and cyclosporine, after LT were retrospectively evaluated. A total of 39 patients who received LT were evaluated. Effects of ITCZ and OH-ITCZ on the concentration/dosage (C/D) ratio of tacrolimus and cyclosporine were analyzed using linear mixed-effects models. The plasma concentrations of OH-ITCZ were about 2.5-fold higher than those of ITCZ. Moreover, there was a significant correlation between the plasma concentrations of ITCZ and OH-ITCZ. Based on parameters obtained in the linear regression analysis, the C/D ratios of cyclosporine and tacrolimus increase by an average of 2.25- and 2.70-fold, respectively, when the total plasma concentration of ITCZ plus OH-ITCZ is 1000 ng/mL. In conclusion, the plasma levels of ITCZ and OH-ITCZ could be key factors in drawing up the criterion for dose reduction of CNIs.
著者
Eriko SATO Ikuko YANO Masahiro SHIMOMURA Satohiro MASUDA Toshiya KATSURA Shin-ichi MATSUMOTO Teru OKITSU Yasuhiro IWANAGA Shinji UEMOTO Ken-ichi INUI
出版者
The Japanese Society for the Study of Xenobiotics
雑誌
Drug Metabolism and Pharmacokinetics (ISSN:13474367)
巻号頁・発行日
vol.24, no.2, pp.175-179, 2009 (Released:2009-05-10)
参考文献数
20
被引用文献数
3

We attempted a switch of mammalian target of rapamycin (mTOR) inhibitors from sirolimus to everolimus, a derivative of sirolimus and now on the market in Japan, in two pancreatic islet transplant patients. Both patients were administered tacrolimus with sirolimus or everolimus. They had been administered 5 or 9 mg sirolimus once a day and had maintained a trough concentration of about 15 ng/mL as measured by high performance liquid chromatography with ultraviolet detection. After the switch from sirolimus to everolimus, they were given 10 or 12 mg/day of everolimus twice a day to maintain a trough concentration of 12-15 ng/mL as measured by a fluorescence polarization immunoassay (FPIA) method. Afterward, the blood concentrations of everolimus and sirolimus after the conversion were measured by high performance liquid chromatography with mass spectrometry and everolimus concentrations were found to be 5-10 ng/mL. These data show that a larger dosage is needed for everolimus than sirolimus to maintain the same trough blood concentration. Data obtained by the FPIA for everolimus should be carefully evaluated after switching from sirolimus to everolimus because of the cross-reactivity of the antibody with sirolimus.