THE PHARMACOKINETICS AND SAFETY OF ZIDOVUDINE IN THE 3RD TRIMESTER OFPREGNANCY FOR WOMEN INFECTED WITH HUMAN-IMMUNODEFICIENCY-VIRUS AND THEIR INFANTS - PHASE-I ACQUIRED-IMMUNODEFICIENCY-SYNDROME CLINICAL-TRIALS GROUP-STUDY (PROTOCOL 082)

OBJECTIVES: We measured the pharmacokinetics and safety of zidovudine in pregnant women infected with human immunodeficiency virus and their offspring. STUDY DESIGN: Asymptomatic human immunodeficiency virus-in fected women with uncomplicated singleton gestations (28 to 36 weeks) underwent parenteral and oral zidovudine treatment during pregnancy an d labor. Maternal and neonatal drug levels were measured at delivery a nd sequentially for 48 hours. Infants were followed up for 18 months. RESULTS: The total body clearance (26.3 +/- 10.1 ml/min/kg), mean term inal elimination phase zidovudine half-life (1.3 +/- 0.2 hours), and u rinary zidovudine recovery were similar to values in nonpregnant adult s. Essentially equivalent zidovudine levels in the mother and neonate at delivery implied little, if any, fetal zidovudine metabolism. The h alf-life of zidovudine in the neonates was tenfold that of the mother. No significant adverse effects were noted in the infant at birth or o n follow-up. CONCLUSIONS: In both mothers and infants the drug appeare d safe and well tolerated with no significant hematologic abnormalitie s.