title: Meta-analysis of Magnetic Marker Monitoring Data to Characterize the Movement of Single Unit Dosage Forms Though the Gastrointestinal Tract Under Fed and Fasting Conditions.
abstract: OBJECTIVE
  To develop a model predicting movement of non-disintegrating single unit dosage forms (or "tablet") through the gastrointestinal tract and characterizing the effect of food intake, based on Magnetic Marker Monitoring data, allowing real-time location of a magnetically labeled formulation.
  
  
  METHODS
  Five studies including 30 individuals in 94 occasions under 3 food status were considered. The mean residence time (MRT) of the tablet and the effect of food intake in proximal (PS) and distal stomach (DS), small intestine (SI), ascending (AC), transverse (TC) and descending colon (DC) were estimated using a Markov model for probabilities of movement.
  
  
  RESULTS
  Under fasting conditions, tablet MRTs were 9.4 min in PS, 10.4 in DS, 246 in SI, 545 in AC, 135 in TC, and 286 in DC. A meal taken simultaneous to tablet intake prolonged tablet MRT to 99 min in PS and to 232 in DS; probability of gastric emptying increased of 89% each hour from 2.25 h after meal. The effect of a gastroileac reflex, caused by a secondary meal, accelerated the transit from terminal SI to AC.
  
  
  CONCLUSIONS
  This model-based knowledge can be used as a part of mechanism-based models for drug absorption, applied for bottom-up predictions and/or top-down estimation.
authors.affiliation: Pharmacometrics Group, Department of Pharmaceutical Biosciences, Uppsala University, Box 591, 75124, Uppsala, Sweden. emilie.henin@gmail.com.|Université Claude Bernard, EMR 3738 Ciblage Thérapeutique en Oncologie - Faculté de Médecine Lyon Sud, BP12, 69921, Oullins Cedex, France. emilie.henin@gmail.com.
authors.forename: Emilie
authors.initials: E
authors.lastname: Hénin
authors.affiliation: Pharmacometrics Group, Department of Pharmaceutical Biosciences, Uppsala University, Box 591, 75124, Uppsala, Sweden.
authors.forename: Martin
authors.initials: M
authors.lastname: Bergstrand
authors.affiliation: Department of Biopharmaceutics and Pharmaceutical Technology, University of Greifswald, Greifswald, D-17487, Germany.
authors.forename: Werner
authors.initials: W
authors.lastname: Weitschies
authors.affiliation: Pharmacometrics Group, Department of Pharmaceutical Biosciences, Uppsala University, Box 591, 75124, Uppsala, Sweden.
authors.forename: Mats O
authors.initials: MO
authors.lastname: Karlsson
mesh_terms: D015415:Biomarkers / Q000378:metabolism*; D002626:Chemistry, Pharmaceutical / Q000379:methods; D004435:Eating / Q000502:physiology; D005215:Fasting; D005746:Gastric Emptying / Q000502:physiology*; D041981:Gastrointestinal Tract / Q000378:metabolism*; D005772:Gastrointestinal Transit / Q000502:physiology*; D006801:Humans; D008280:Magnetics / Q000379:methods; D011336:Probability; D013607:Tablets / Q000378:metabolism*
chemical_list: D015415:Biomarkers; D013607:Tablets
keywords: Food effect; GI transit; Markov model; Tablet movement