title: Pharmacokinetics and safety in rhesus monkeys of a monoclonal antibody-GDNF fusion protein for targeted blood-brain barrier delivery.
abstract: OBJECTIVE
  Glial-derived neurotrophic factor (GDNF) is a potential therapy for stroke, Parkinson's disease, or drug addiction. However, GDNF does not cross the blood-brain barrier (BBB). GDNF is re-engineered as a fusion protein with a chimeric monoclonal antibody (MAb) to the human insulin receptor (HIR), which acts as a molecular Trojan horse to deliver the GDNF across the BBB. The pharmacokinetics (PK), toxicology, and safety pharmacology of the HIRMAb-GDNF fusion protein were investigated in Rhesus monkeys.
  
  
  METHODS
  The fusion protein was administered as an intravenous injection at doses up to 50 mg/kg over a 60 h period to 56 Rhesus monkeys. The plasma concentration of the HIRMAb-GDNF fusion protein was measured with a 2-site sandwich ELISA.
  
  
  RESULTS
  No adverse events were observed in a 2-week terminal toxicology study, and no neuropathologic changes were observed. The PK analysis showed a linear relationship between plasma AUC and dose, a large systemic volume of distribution, as well as high clearance rates of 8-10 mL/kg/min.
  
  
  CONCLUSIONS
  A no-observable-adverse-effect level is established in the Rhesus monkey for the acute administration of the HIRMAb-GDNF fusion protein. The fusion protein targeting the insulin receptor has a PK profile similar to a classical small molecule.
authors.affiliation: ArmaGen Technologies, Inc., 914 Colorado Ave., Santa Monica, California 90401, USA. wpardridge@armagen.com
authors.forename: William M
authors.initials: WM
authors.lastname: Pardridge
authors.forename: Ruben J
authors.initials: RJ
authors.lastname: Boado
mesh_terms: D000818:Animals; D000911:Antibodies, Monoclonal / Q000008:administration & dosage / Q000009:adverse effects / Q000493:pharmacokinetics*; D001812:Blood-Brain Barrier / Q000187:drug effects / Q000378:metabolism*; D004305:Dose-Response Relationship, Drug; D016503:Drug Delivery Systems / Q000379:methods*; D005260:Female; D051100:Glial Cell Line-Derived Neurotrophic Factor / Q000008:administration & dosage / Q000009:adverse effects / Q000493:pharmacokinetics*; D008253:Macaca mulatta; D008297:Male; D011993:Recombinant Fusion Proteins / Q000008:administration & dosage / Q000009:adverse effects / Q000493:pharmacokinetics*
chemical_list: D000911:Antibodies, Monoclonal; D051100:Glial Cell Line-Derived Neurotrophic Factor; D011993:Recombinant Fusion Proteins