Randomized study of two doses of didanosine in children infected with human immunodeficiency virus.

2'3'-Dideoxyinosine (didanosine) is a nucleoside analog active in vitro against human immunodeficiency virus. Few data are available regarding its use for the treatment of children. In a single-center, randomized, open-label trial, we compared two dosages of didanosine (120 vs 270 mg/m2 per day) for at least 6 months in 34 children infected with human immunodeficiency virus who had become resistant to or were intolerant of zidovudine. Serum levels of didanosine 1 hour after administration were significantly different in the two groups and remained stable with time. There was a significant reduction in human immunodeficiency virus-p24 antigenemia and quantitative cellular viremia with time but no difference between the two groups. The intensity of the biologic response, however, was significantly higher in the patients who had more than 50 CD4+ cells 10(6)/L at inclusion. No pancreatic or neurologic toxic effects were observed. In five children, liver function abnormalities developed that are unusual in this setting, and the death of one child from unexplained hepatocellular failure suggests that didanosine may be hepatotoxic. Three of these five children had preexisting liver disease. Although no definite conclusion can be made as to the optimal dose, there were no major differences between the two administration schedules in terms of biologic effects and tolerability.