title: Enfuvirtide plasma levels and injection site reactions using a needle-free gas-powered injection system (Biojector).
abstract: OBJECTIVE
  To assess the use of the Biojector B2000 needle-free gas-powered injection system for subcutaneous administration of enfuvirtide in HIV-infected patients and to compare this system with standard needles and syringes with respect to ease of use, severity of injection site reactions (ISR), and enfuvirtide plasma levels.
  
  
  METHODS
  An observational study among 32 treatment-experienced HIV clinic patients receiving enfuvirtide.
  
  
  METHODS
  Adult patients were assessed before and after switching from standard needles to the Biojector for enfuvirtide administration. Patients used the Biojector for up to 24 weeks and rated ease of use from 0 (easy) to 3 (difficult). ISR were graded from 0 to 31 for signs and symptoms (erythema, induration, pruritus, nodules/cysts, ecchymosis), duration of individual lesions, and number of lesions. Plasma was collected pre-dose and 1 h post-dose for enfuvirtide measurement. The high-pressure liquid chromatography with tandem mass spectrometry method used was specific for enfuvirtide over its known plasma metabolite. Wilcoxon rank sum tests were used to compare needle-based and Biojector outcomes.
  
  
  RESULTS
  The Biojector was rated as being significantly easier to use (P < 0.001) and reduced the occurrence of ISR compared with standard needles (P < 0.001). Enfuvirtide plasma levels were not statistically different between the two administration methods at either pre-dose trough (P = 0.41) or 1 h post-dose (P = 0.74).
  
  
  CONCLUSIONS
  The Biojector needle-free injection system was easy to use for enfuvirtide administration and was associated with a decreased severity of ISR. Plasma enfuvirtide levels pre-dose and 1 h post-dose were comparable when injecting with standard needles or the Biojector.
authors.affiliation: British Columbia Centre for Excellence in HIV/AIDS, Vancouver, British Columbia, Canada. mharris@cfenet.ubc.ca
authors.forename: Marianne
authors.initials: M
authors.lastname: Harris
authors.forename: Ruth
authors.initials: R
authors.lastname: Joy
authors.forename: Gerene
authors.initials: G
authors.lastname: Larsen
authors.forename: Monica
authors.initials: M
authors.lastname: Valyi
authors.forename: Ekaterina
authors.initials: E
authors.lastname: Walker
authors.forename: Lloyd W
authors.initials: LW
authors.lastname: Frick
authors.forename: Robin M
authors.initials: RM
authors.lastname: Palmatier
authors.forename: Stephen A
authors.initials: SA
authors.lastname: Wring
authors.forename: Julio Sg
authors.initials: JS
authors.lastname: Montaner
mesh_terms: D000328:Adult; D000077560:Enfuvirtide; D004867:Equipment Design; D005500:Follow-Up Studies; D015700:HIV Envelope Protein gp41 / Q000008:administration & dosage* / Q000627:therapeutic use; D023581:HIV Fusion Inhibitors / Q000008:administration & dosage* / Q000493:pharmacokinetics / Q000627:therapeutic use; D015658:HIV Infections / Q000188:drug therapy* / Q000378:metabolism; D015497:HIV-1; D006801:Humans; D007277:Injections, Jet / Q000295:instrumentation / Q000379:methods; D009339:Needles; D017060:Patient Satisfaction; D010446:Peptide Fragments / Q000008:administration & dosage* / Q000493:pharmacokinetics / Q000627:therapeutic use; D012867:Skin / Q000187:drug effects; D018709:Statistics, Nonparametric; D013594:Syringes
chemical_list: D015700:HIV Envelope Protein gp41; D023581:HIV Fusion Inhibitors; D010446:Peptide Fragments; D000077560:Enfuvirtide