A Multicenter Phase II Double-Blind Exploratory Study to Evaluate Differences Among Various Zidovudine/Didanosine Regimens on Quantitative Measures of Viral Burden in Relatively Early HIV-1 Infection

To determine the relative antiviral activity and safety of zidovudine ( AZT ) and didanosine ( ddI ) alone and in combination, as well as in various sequences of administration. The relative efficacy of the approved antiretrovirals in early HIV-1 disease is unclear; thus, a study is needed to evaluate the ability of these various nucleoside analogs to limit pathogenicity. The relative efficacy of the approved antiretrovirals in early HIV-1 disease is unclear; thus, a study is needed to evaluate the ability of these various nucleoside analogs to limit pathogenicity. Patients undergo observation for 2 weeks, then are randomized to one of six treatment arms to receive ddI alone or in sequence or combination with AZT for 16-32 weeks, followed by 4 weeks of post-treatment evaluation. The regimens are: ddI alone for 32 weeks; AZT for 16 weeks followed by ddI for 16 weeks; AZT for 16 weeks followed by AZT/ddI combination for 16 weeks; ddI for 16 weeks followed by AZT for 16 weeks; AZT/ddI combination for 32 weeks; and placebo for 32 weeks. PER AMENDMENT 6/18/96: NOTE: Patients enrolled under version 3 of the study will terminate treatment at week 16 and have a 4 week follow up.