A multiple drug interaction study of stavudine with agents for opportunistic infections in human immunodeficiency virus-infected patients

The effects of multiple opportunistic infection medications on stavudine ph armacokinetics were evaluated. Ten patients with CD4 counts of less than 20 0 cells/mm(3) received stavudine (40 mg twice daily) in combination with on e to three other drugs used to treat opportunistic infections. Serial blood samples for stavudine concentrations were collected after 1 week of therap y on each regimen and assayed for stavudine by using a validated high-press ure liquid chromatography method. Although the maximum concentration of dru g in serum was significantly decreased when the drug was given in combinati on with three opportunistic infection medications, the area under the conce ntration-time curve did not significantly differ across various treatment r egimens. Stavudine exposure was not significantly altered by multiple conco mitant medications. Side effects were minor throughout the 3-month study pe riod. The tolerability of stavudine, combined with its lack of drug interac tions, makes it an attractive agent for use as part of a combination regime n.