Pharmacokinetics and Safety of Melatonin Prolonged-Release Tablets in Healthy Chinese Subjects

Melatonin prolonged-release tablet is indicated as monotherapy for the short-term treatment of primary insomnia characterized by poor quality of sleep in patients who are aged 55 or over. This study evaluated the safety and pharmacokinetics of it after single or multiple doses in healthy Chinese subjects. Subjects were assigned to receive a single dose of 2, 4, or 8 mg after an overnight fasting or 2 mg within 30 min after consuming breakfast or multiple doses of 2 mg once daily for 7 days. In the single-dose study, C-max reached at 0.79 h and the mean t(1/2) was 2.22 h. Area under curve (AUC) and C-max increased proportionally over the range 2-8 mg. C-max and AUC in the non-fasted subjects were lower compared with those in the fasted subjects. No accumulation appeared upon repeated doses of 2 mg once daily for 4 days.