The efficacy of liposomal doxorubicin for treating Kaposi's sarcoma (KS) in patients infected with human immunodeficiency virus (HIV) was studied. Eight men with HIV infection and KS were to be given liposomal doxorubicin 20 mg/sq m i.v. monthly for six months and 10 mg/sq m i.v. monthly thereafter, depending on the response. They were assessed for the onset, extent, and duration of clinical response; relapse; adverse effects; development of new opportunistic infections; quality of life; and survival. Five patients had a clinical complete response (i.e., complete resolution of the manifestations of KS, as determined by physical examination but not confirmed by biopsy) and three patients had a partial response to the induction regimen of liposomal doxorubicin. Relapse occurred in all patients in whom therapy was stopped; reinstatement of therapy elicited a partial response. Neutropenia occurred in two patients; filgrastim therapy enabled the liposomal doxorubicin therapy to continue uninterrupted. Thromboembolic events developed or were suspected in three patients, although they may not have been caused by liposomal doxorubicin. Monthly i.v. administration of liposomal doxorubicin partially or completely eliminated the clinical manifestations of Kaposi's sarcoma in eight men infected with HIV.