AIDS is caused by a retrovirus, HTLV-III, which is susceptible in vitro to some currently available drugs. This study is an ongoing effort to test these drugs in viremic patients with AIDS in order to assess the antiviral properties of these drugs, as well as their effects on immune reconstitution, patient survival, and toxicity. Suramin, Ribavirin, Azidothymidine, Phosphonoformate and HPA23 have been identified as having antiviral properties. Patients have been treated to date with each of these agents. Conversion of blood cultures from positive to negative has not occurred consistently. Toxicity is being assessed, but Suramin has already been shown to be associated with unacceptable toxicity. The significance of this work is that antiviral therapy is the most logical approach to the therapy of AIDS. Facilities available in NIAID make the Clinical Center one of the few centers where careful assessment of this type of therapy can currently be performed.