Immobilized forms of daunorubicin in patients with acute leukemia

AIM: To study pharmacokinetics of liposomal daunorubicine DaunoXome and daunorubicine (rubomycin) associated with red cells: to assess their effectiveness and toxicity in patients with acute leukemia. MATERIALS AND METHODS: 7 patients with resistant or recurrent acute leukemia entered the trial. Of them 2 patients had acute myeloid leukemia. They received DaunoXome in dose 100 mg in days 1, 2 and 3 of 7 + 3 program. 1 patient had pretreated acute promyelocytic leukemia. This patient received 5-day course of DaunoXome in a dose 100 mg in the presence of ATRA therapy. 4 patients were given single dose daunorubicin associated with autoerythrocytes in the courses RACOP and 7 + 3 in a dose 45 mg/m2. Concentrations of free, bound and liposomal daunorubicin were determined spectrofluorimetrically in chlorophorm extracts of plasm, blood, liquor and bone marrow specimens. RESULTS: Immobilization of daunorubicin on the red cells and liposomes changes pharmacokinetics of the drug: peak concentrations change and the area under the concentration curve increases. Tolerance of DaunoXome and daunorubicine associated with red cells was satisfactory in all the cases: clinical and echo-CG signs of cordiotoxicity were absent, myelotoxicity was similar to that of free daunorubicine. DaunoXome was effective in 2 of 3 patients with acute myeloblastic leukemia. CONCLUSION: The findings are of practical interest for physicians designing new programs of therapy of acute leukemia.