STATE-OF-THE-ART OF ZIDOVUDINE MONITORING

Zidovudine, the only drug approved by the FDA for the treatment of AIDS, has well-documented efficacy, but numerous toxic side effects. Despite considerable knowledge of the pharmacology of the drug, however, a therapeutic concentration range has not been established. This article reviews methodologies used for measurement of zidovudine in serum. Procedures for several methods are described and comparisons offered. In addition to methodologies, other issues of concern in establishing or maintaining a zidovudine monitoring service are also discussed, including the clinical relevance of routine zidovudine monitoring, method-related quality control, and laboratory safety. Methodologies currently being developed to measure the active intracellular metabolites of zidovudine are also described. These methods are believed to be the key to fully understanding the relationships between zidovudine pharmacology, toxicity, and efficacy.