Long-term Suppression of HIV-1 by Hydroxyurea and Didanosine

To the Editor. —The use of hydroxyurea has been brought rapidly from laboratory studies to clinical implementation. After our initial demonstration of the potential use of hydroxyurea to inhibit human immunodeficiency virus (HIV)-1 replication,¹other laboratories have shown that hydroxyurea and didanosine appear to be a powerful combination and lead to synergistic effects.² In this study, 6 consecutive patients (Table) were treated with a combination of hydroxyurea (250-mg dose, 4 times per day) and didanosine (200-mg dose, 2 times per day). The group represented a heterogeneous population. Three patients had acquired immunodeficiency syndrome (AIDS), and 1 (patient 4) was enrolled following an episode of acute mononucleosis-like HIV syndrome 8 weeks after documented seroconversion. The response to treatment revealed a consistent pattern independent of previous exposure to antiretroviral treatment and disease stage. An initial sharp decrease in viremia (average, 84.5%) was observed in all patients 2 to 6 weeks after