De-Wei Shang1, Zhan-Zhang Wang1, Hai-Tang Hu2, Yue-Feng Zhang1, Xiao-Jia Ni1, Hao-Yang Lu1, Ming Zhang1, Jin-Qing Hu1, Chang Qiu1, Huan Peng1, Ling-Fang Shen1, Yu-Guan Wen3. 1. The Affiliated Brain Hospital of Guangzhou Medical University (Guangzhou Huiai Hospital), 36 Mingxin Road, Guangzhou, 510370, China. 2. Clinical Research Center, Livzon Pharmaceutical Group Co., Ltd., 132 Guihua North Road, Zhuhai, 519020, China. 3. The Affiliated Brain Hospital of Guangzhou Medical University (Guangzhou Huiai Hospital), 36 Mingxin Road, Guangzhou, 510370, China. wenyuguande@163.com.
Abstract
PURPOSE: The purpose of this study was to investigate the potential effects of a meal and grapefruit juice on the pharmacokinetics of blonanserin and its metabolite N-desethyl blonanserin in healthy Chinese volunteers. METHODS: This was a single-centre, open-label, fixed-sequence study, where 12 healthy Chinese volunteers received a single dose of 8 mg blonanserin after an overnight fast in period 1 (reference), a high-fat meal during period 2 and with co-administration of 250 mL of grapefruit juice in period 3. The washout period was 7 days. Series of plasma samples were collected after each dose to determine concentrations of blonanserin and its metabolite N-desethyl blonanserin using liquid chromatography-tandem mass spectrometry. Pharmacokinetic parameters were estimated by non-compartmental analysis and compared between periods by standard average bioequivalence ANOVA. Adverse events were monitored throughout the study. RESULTS: All subjects completed the study. High-fat meals significantly increased blonanserin exposure (AUCt) 2.58-fold (90% CI 2.21, 3.02), relative to the reference period. Co-administration of blonanserin with grapefruit juice remarkably prolonged elimination half-life of blonanserin (from 9.7 to 21.4 h) and significantly increased exposures to blonanserin and N-desethyl blonanserin by 5.82-fold (90% CI 4.57, 7.42) and 1.81-fold (90% CI 1.65, 1.98), respectively. CONCLUSIONS: These results suggested that blonanserin was largely metabolised in the intestinal tract before becoming systemically available, and both food and grapefruit juice enhanced exposure to blonanserin and N-desethyl blonanserin. Grapefruit juice increased bioavailability and may have reduced systemic clearance of blonanserin. Further intestinal CYP3A4 and hepatic CYP3A4 might be postulated to explain the delayed elimination of blonanserin. Dose adjustment of blonanserin is needed on the basis of co-intake of known strong CYP3A4 inhibitor. Patients taking high-dose blonanserin also need to be cautious about the ingestion of grapefruit juice.
PURPOSE: The purpose of this study was to investigate the potential effects of a meal and grapefruit juice on the pharmacokinetics of blonanserin and its metabolite N-desethyl blonanserin in healthy Chinese volunteers. METHODS: This was a single-centre, open-label, fixed-sequence study, where 12 healthy Chinese volunteers received a single dose of 8 mg blonanserin after an overnight fast in period 1 (reference), a high-fat meal during period 2 and with co-administration of 250 mL of grapefruit juice in period 3. The washout period was 7 days. Series of plasma samples were collected after each dose to determine concentrations of blonanserin and its metabolite N-desethyl blonanserin using liquid chromatography-tandem mass spectrometry. Pharmacokinetic parameters were estimated by non-compartmental analysis and compared between periods by standard average bioequivalence ANOVA. Adverse events were monitored throughout the study. RESULTS: All subjects completed the study. High-fat meals significantly increased blonanserin exposure (AUCt) 2.58-fold (90% CI 2.21, 3.02), relative to the reference period. Co-administration of blonanserin with grapefruit juice remarkably prolonged elimination half-life of blonanserin (from 9.7 to 21.4 h) and significantly increased exposures to blonanserin and N-desethyl blonanserin by 5.82-fold (90% CI 4.57, 7.42) and 1.81-fold (90% CI 1.65, 1.98), respectively. CONCLUSIONS: These results suggested that blonanserin was largely metabolised in the intestinal tract before becoming systemically available, and both food and grapefruit juice enhanced exposure to blonanserin and N-desethyl blonanserin. Grapefruit juice increased bioavailability and may have reduced systemic clearance of blonanserin. Further intestinal CYP3A4 and hepatic CYP3A4 might be postulated to explain the delayed elimination of blonanserin. Dose adjustment of blonanserin is needed on the basis of co-intake of known strong CYP3A4 inhibitor. Patients taking high-dose blonanserin also need to be cautious about the ingestion of grapefruit juice.
Entities:
Keywords:
Blonanserin; Food/herbal drug interactions; N-desethyl blonanserin; Pharmacokinetics; Schizophrenia
Authors: H Glaeser; D G Bailey; G K Dresser; J C Gregor; U I Schwarz; J S McGrath; E Jolicoeur; W Lee; B F Leake; R G Tirona; R B Kim Journal: Clin Pharmacol Ther Date: 2007-01-10 Impact factor: 6.875