Arzneimittelforschung 2012; 62(12): 561-565
DOI: 10.1055/s-0032-1327570
Original Article
© Georg Thieme Verlag KG Stuttgart · New York

Pharmacokinetics and Safety of Eszopiclone in Healthy Chinese Volunteers

Data from a Single-center, Open-label, Single and Multiple Dose, Randomized, Crossover Pharmacokinetic Study of Eszopiclone under Fasting ConditionsF. Wu1, X. L. Zhao1, M. J. Wei2, S. M. Wang1, H. Zhou1, S. J. Guo1, P. Zhang2
  • 1Department of Clinical Pharmacology, Beijing Tongren Hospital, Capital Medical University, Beijing, China
  • 2Institute of Clinical Pharmacology, Peking University, Beijing, China
Further Information

Publication History

received 28 January 2012

accepted 05 September 2012

Publication Date:
04 October 2012 (eFirst)



The main objective of this study was to investigate the pharmacokinetic characters of eszopiclone (CAS: 138729-47-2) after single and multiple-dose oral administration in healthy adult Chinese volunteers.


In single-dose study, 12 subjects were given oral administrations of 1.5, 3 and 6 mg eszopiclone in an open-label, randomized, crossover fashion. In multiple-dose study, 8 subjects were given 3 mg eszopiclone once daily consecutively for 7 days. Blood samples were collected over 24 h and plasma eszopiclone were determined using a validated liquid chromatography/mass spectrometry (LC/MS/MS) assay. The safety and tolerability of eszopiclone was evaluated by adverse events recording, physical examination, laboratory testing, vital signs, and 12-lead ECG findings.


The main pharmacokinetic parameters of eszopiclone after single-dose administration were as follows: doses of 1.5, 3 and 6 mg; Cmax of 18.08±4.65, 38.29±15.41 and 76.38±23.34 ng/ml; Tmax of 0.94±0.39, 1.04±0.63 and 1.08±0.51 h; AUC0–24 of 110.90±23.06, 227.36±62.41 and 504.10±140.13 ng*h/ml; elimination half-lives of 5.84±1.03, 5.53±1.91 and 6.17±1.23 h. After multiple-dose administration, the steady-state levels of eszopiclone were achieved by the 4th day, and the main pharmacokinetic parameters were Css_max at 33.43±5.63 ng/ml and AUCss (0–24) at 263.30±51.21 ng*h/ml. The most common adverse event was bitter or abnormal taste. All the adverse events were judged as mild to moderate and resolved without any medication.


The pharmacokinetic character of eszopiclone is linear and dose-proportional over the range of 1.5–6 mg. The systemic exposure does not accumulate with once-daily administrations. Eszopiclone appears to have good safety and is well tolerated.