A multicenter phase II study of the intravenous administration of liposomal tretinoin in patients with acquired immunodeficiency syndrome-associated Kaposi's sarcoma

BACKGROUND. A multicenter trial was conducted to determine the efficacy and toxicity of escalating dosages of liposomal tretinoin (all-trans-retinoic acid) administered once or three times weekly in patients with acquired immunodeficiency syndrome (AIDS)-associated Kaposi sarcoma. METHODS. Seventy-six patients with acquired immunodeficiency syndrome (AIDS)-associated Kaposi sarcoma were randomized to receive the study drug either once (n = 30) or 3 times weekly (n = 46). The starting dosage was 60 mg/m(2), which was escalated to 90 mg/m(2) and then 120 mg/m(2) if the drug was well tolerated (less than or equal to Grade 2 toxicities [according to the Southwest Oncology Group toxicity scale]). Four weeks of therapy constituted 1 cycle; patients could receive up to 8 cycles and those who completed 8 cycles were given the option of receiving extended therapy. Clinical response was defined as complete response (CR), partial response (PR), or stable disease (SD). RESULTS. Efficacy was assessed after the completion of 3 treatment cycles; 28.9% of patients (22 of 76 patients) responded (no CRs, 1 PR, and 21 SDs). Among the patients receiving treatment 3 times weekly, 16 of 49 patients (32.7%) achieved a clinical response at the end of the third treatment cycle (no CRs, I PR, and 15 SDs). Concomitant or prior use of protease inhibitors did not appear to affect the patient's response to treatment (P = 0.183). CONCLUSIONS. Liposomal tretinoin is a new therapeutic agent that has been reported to have some clinical activity in patients with AIDS-associated Kaposi sarcoma. A three-times-per-week dosing schedule was noted to be more effective compared with a once-a-week schedule without any significant difference in toxicity reported. Cancer 2002;95:2555-61. (C) 2002 American Cancer Society.