title: Dynamics and kinetics of a modified-release formulation of zolpidem: comparison with immediate-release standard zolpidem and placebo.
abstract: Modified-release (MR) zolpidem was developed to maintain effective plasma concentrations during the 3- to 6-hour post-dosage interval, corresponding to the middle portion of the typical sleep interval. Modified-release zolpidem (12.5 mg), standard immediate-release (IR) zolpidem (10 mg), and placebo were compared in a double-blind, single-dose, 3-way crossover daytime study of healthy volunteers (n = 70 completers). Effect areas for electroencephalographic beta amplitude during 0 to 8 hours and 3 to 6 hours after dosage were greater for MR compared to IR (P < .001). The digit-symbol substitution test and sedation rating scales behaved similarly. MR and IR did not differ in effects at 8 hours post-dosage nor in halflife or clearance. Time of peak plasma concentration (tmax) was significantly longer for MR (2.4 vs 2.0 hours, P < .004), and dose-normalized peak plasma concentration (Cmax) was lower (12.2 vs 14.0 ng/mL/mg, P < .001). MR zolpidem also had greater area under the plasma concentration curve (AUC) during the 3- to 6-hour interval (P < .001). Thus, MR zolpidem produces sustained plasma levels compared to IR, with resulting enhancement of pharmacodynamic effects in the 3- to 6-hour post-dosage interval.
authors.affiliation: Department of Pharmacology and Experimental Therapeutics, Tufts University School of Medicine, 136 Harrison Avenue, Boston, MA 02111, USA. dj.greenblatt@tufts.edu
authors.forename: David J
authors.initials: DJ
authors.lastname: Greenblatt
authors.forename: Eric
authors.initials: E
authors.lastname: Legangneux
authors.forename: Jerold S
authors.initials: JS
authors.lastname: Harmatz
authors.forename: Estelle
authors.initials: E
authors.lastname: Weinling
authors.forename: Jon
authors.initials: J
authors.lastname: Freeman
authors.forename: Kathleen
authors.initials: K
authors.lastname: Rice
authors.forename: Gary K
authors.initials: GK
authors.lastname: Zammit
mesh_terms: D000328:Adult; D000704:Analysis of Variance; D019540:Area Under Curve; D001611:Beta Rhythm / Q000187:drug effects; D018592:Cross-Over Studies; D003692:Delayed-Action Preparations / Q000009:adverse effects / Q000493:pharmacokinetics*; D004311:Double-Blind Method; D005260:Female; D006261:Headache / Q000139:chemically induced; D006801:Humans; D006993:Hypnotics and Sedatives / Q000009:adverse effects / Q000493:pharmacokinetics; D008297:Male; D008657:Metabolic Clearance Rate; D008875:Middle Aged; D009325:Nausea / Q000139:chemically induced; D011725:Pyridines / Q000009:adverse effects / Q000097:blood / Q000493:pharmacokinetics*; D013607:Tablets; D013997:Time Factors; D014839:Vomiting / Q000139:chemically induced; D000077334:Zolpidem
chemical_list: D003692:Delayed-Action Preparations; D006993:Hypnotics and Sedatives; D011725:Pyridines; D013607:Tablets; D000077334:Zolpidem