title: Pharmacokinetic profile of a 24-hour controlled-release OROS formulation of hydromorphone in the presence and absence of food.
abstract: BACKGROUND
  The objective of this study was to compare the pharmacokinetic profile of a novel, once-daily, controlled-release formulation of hydromorphone (OROS hydromorphone) under fasting conditions with that immediately after a high-fat breakfast in healthy volunteers. The effect of the opioid antagonist naltrexone on fasting hydromorphone pharmacokinetics also was evaluated.
  
  
  METHODS
  In an open-label, three-way, crossover study, 30 healthy volunteers were randomized to receive a single dose of 16 mg OROS hydromorphone under fasting conditions, 16 mg OROS hydromorphone under fed conditions, or 16 mg OROS hydromorphone under fasting conditions with a naltrexone 50-mg block. Plasma samples taken pre-dose and at regular intervals up to 48 hours post-dose were assayed for hydromorphone concentrations. Analysis of variance was performed on log-transformed data; for mean ratios of 0.8 to 1.2 (20%), differences were considered minimal. Bioequivalence was reached if 90% confidence intervals (CI) of treatment mean ratios were between 80% and 125%.
  
  
  RESULTS
  The mean geometric ratios of the fed and fasting treatment groups for maximum plasma concentration (Cmax) and area under the concentration-time curve (AUC0-t; AUC0-infinity) were within 20%. Confidence intervals were within 80% to 125% for AUC0-t and AUC0-infinity but were slightly higher for Cmax (105.9% and 133.3%, respectively). With naltrexone block, the hydromorphone Cmax increased by 39% and the terminal half-life decreased by 4.5 hours. There was no significant change in Tmax, AUC0-t or AUC0-infinity.
  
  
  CONCLUSIONS
  Standard bioavailability measures show minimal effect of food on the bioavailability of hydromorphone from OROS hydromorphone. Naltrexone co-administration results in a slight increase in the rate of absorption but not the extent of absorption.
authors.affiliation: ALZA Corporation, Mountain View, CA, USA. gsathyan@alzus.jnj.com
authors.forename: Gayatri
authors.initials: G
authors.lastname: Sathyan
authors.forename: Emily
authors.initials: E
authors.lastname: Xu
authors.forename: John
authors.initials: J
authors.lastname: Thipphawong
authors.forename: Suneel K
authors.initials: SK
authors.lastname: Gupta
mesh_terms: D000328:Adult; D000701:Analgesics, Opioid / Q000008:administration & dosage / Q000097:blood / Q000493:pharmacokinetics*; D019540:Area Under Curve; D001682:Biological Availability; D018592:Cross-Over Studies; D003692:Delayed-Action Preparations; D005260:Female; D018565:Food-Drug Interactions; D006207:Half-Life; D006801:Humans; D004091:Hydromorphone / Q000008:administration & dosage / Q000097:blood / Q000493:pharmacokinetics*; D008297:Male; D008875:Middle Aged; D009271:Naltrexone / Q000008:administration & dosage; D009292:Narcotic Antagonists / Q000008:administration & dosage
chemical_list: D000701:Analgesics, Opioid; D003692:Delayed-Action Preparations; D009292:Narcotic Antagonists; D009271:Naltrexone; D004091:Hydromorphone