title: Clinical pharmacology of exogenously administered alkaline phosphatase.
abstract: OBJECTIVE
  To evaluate the clinical pharmacology of exogenous alkaline phosphatase (AP).
  
  
  METHODS
  Randomized, double-blind, placebo-controlled sequential protocols of (1) ascending doses and infusion duration (volunteers) and (2) fixed dose and duration (patients) were conducted at clinical pharmacology and intensive care units. A total of 103 subjects (67 male volunteers and 36 patients with severe sepsis) were administered exogenous, 10-min IV infusions (three ascending doses) or 24-72 h continuous (132.5-200 U kg(-1) 24 h(-1)) IV infusion with/without preceding loading dose and experimental endotoxemia for evaluations of pharmacokinetics, pharmacodynamics, safety parameters, antigenicity, inflammatory markers, and outcomes.
  
  
  RESULTS
  Linearity and dose-proportionality were shown during 10-min infusions. The relatively short elimination half-life necessitated a loading dose to achieve stable enzyme levels. Pharmacokinetic parameters in volunteers and patients were similar. Innate immunity response was not significantly influenced by AP, while renal function significantly improved in sepsis patients.
  
  
  CONCLUSIONS
  The pharmacokinetics of exogenous AP is linear, dose-proportional, exhibit a short half-life, and are not influenced by renal impairment or dialysis.
authors.affiliation: Department of Intensive Care Medicine (551), Radboud University Nijmegen Medical Centre, Nijmegen, The Netherlands. p.pickkers@ic.umcn.nl
authors.forename: P
authors.initials: P
authors.lastname: Pickkers
authors.forename: F
authors.initials: F
authors.lastname: Snellen
authors.forename: P
authors.initials: P
authors.lastname: Rogiers
authors.forename: J
authors.initials: J
authors.lastname: Bakker
authors.forename: P
authors.initials: P
authors.lastname: Jorens
authors.forename: J
authors.initials: J
authors.lastname: Meulenbelt
authors.forename: H
authors.initials: H
authors.lastname: Spapen
authors.forename: J E
authors.initials: JE
authors.lastname: Tulleken
authors.forename: R
authors.initials: R
authors.lastname: Lins
authors.forename: S
authors.initials: S
authors.lastname: Ramael
authors.forename: M
authors.initials: M
authors.lastname: Bulitta
authors.forename: J G
authors.initials: JG
authors.lastname: van der Hoeven
mesh_terms: D000328:Adult; D000368:Aged; D000469:Alkaline Phosphatase / Q000008:administration & dosage* / Q000009:adverse effects / Q000097:blood / Q000493:pharmacokinetics / Q000494:pharmacology*; D004311:Double-Blind Method; D019446:Endotoxemia / Q000188:drug therapy*; D005260:Female; D006207:Half-Life; D006801:Humans; D007262:Infusions, Intravenous; D007378:Interleukins / Q000097:blood; D008297:Male; D008875:Middle Aged; D013997:Time Factors; D014409:Tumor Necrosis Factor-alpha / Q000097:blood
chemical_list: D007378:Interleukins; D014409:Tumor Necrosis Factor-alpha; D000469:Alkaline Phosphatase