title: Pharmacokinetics and safety of concentration-controlled oral zidovudine therapy.
abstract: OBJECTIVE
  To evaluate the pharmacokinetics, safety, and feasibility of concentration-controlled oral zidovudine therapy.
  
  
  METHODS
  Randomized, crossover, open-label study.
  
  
  METHODS
  University-affiliated general clinical research center.
  
  
  METHODS
  Eight individuals infected with the human immunodeficiency virus with CD4+ lymphocyte counts of 100 cells/microliter or greater.
  
  
  METHODS
  During the 24-week study, patients received oral zidovudine regimens that consisted of a standard fixed dose of 500 mg/day and a concentration-controlled regimen designed to maintain a steady-state plasma concentration (Css) of 0.187 +/- 0.04 mg/L (0.7 +/- 0.14 microM).
  
  
  RESULTS
  The mean Css during standard therapy was 0.170 +/- 0.024 mg/L versus 0.205 +/- 0.021 mg/L with the concentration-controlled regimen (p = 0.025). Respective mean changes in hemoglobin were -0.02 g/dl (range -0.9-0.9 g/dl) and -0.30 g/dl (range -1.5-0.4 g/dl, p = 0.67). The absolute neutrophil count decreased 0.90 x 10(9)/L during standard therapy and increased 0.40 x 10(9)/L during concentration-controlled therapy (p = 0.07). The regimens did not differ in toxicity.
  
  
  CONCLUSIONS
  Concentration-controlled oral antiretroviral therapy with zidovudine is feasible and safe, and provides pharmacologic data to determine the regimen's virologic and immunologic benefits.
authors.affiliation: College of Pharmacy, University of Minnesota Health Sciences Center, Minneapolis, USA.
authors.forename: E P
authors.initials: EP
authors.lastname: Acosta
authors.forename: K
authors.initials: K
authors.lastname: Henry
authors.forename: L M
authors.initials: LM
authors.lastname: Page
authors.forename: A
authors.initials: A
authors.lastname: Erice
authors.forename: H H
authors.initials: HH
authors.lastname: Balfour
authors.forename: C V
authors.initials: CV
authors.lastname: Fletcher
mesh_terms: D000284:Administration, Oral; D000328:Adult; D019380:Anti-HIV Agents / Q000008:administration & dosage / Q000009:adverse effects / Q000493:pharmacokinetics*; D018592:Cross-Over Studies; D005260:Female; D015658:HIV Infections / Q000097:blood / Q000188:drug therapy*; D006801:Humans; D008297:Male; D008875:Middle Aged; D015215:Zidovudine / Q000008:administration & dosage / Q000009:adverse effects / Q000493:pharmacokinetics*
chemical_list: D019380:Anti-HIV Agents; D015215:Zidovudine