Camptothecin analogs ( @entity2600 or XXXX ) plus high-dose @entity786 as preparative regimens for antibody-based immunotherapy in resistant @entity521 .

@entity1 @entity137 @entity2600 @entity1261 @entity786 @entity15856 @entity1891 @entity521 @entity236 @entity2335 @entity1945
PURPOSE: We used high-dose @entity786 plus @entity1945 / @entity1891 (CTV) or @entity2600 (C/I) in @entity1 with resistant @entity521 . The aim was to use a regimen with little risk to major organs to (a) achieve or consolidate remission in heavily treated @entity1 and to (b) induce an immunological state conducive to passive immunotherapy with the murine 3F8 antibody. EXPERIMENTAL DESIGN: CTV and C/I included @entity786 140 mg/kg ( approximately 4200 mg/m(2)). With CTV, @entity1945 2 mg/m(2) was infused i.v. (30 min) on days 1-4 (total, 8 mg/m(2)), and @entity1891 0.067 mg/kg was injected on day 1. With C/I, @entity2600 , 50 mg/m(2) was infused i.v. (1 h) on days 1-5 (total, 250 mg/m(2)). Mesna and @entity1261 were used. RESULTS: Twenty-nine @entity1 received 38 courses of CTV, and 26 @entity1 received 38 courses of C/I. All @entity1 had previously received @entity1945 , a hemopoietic stem-cell transplant, and/or high-dose @entity786 . CTV and C/I caused myelosuppression of comparably prolonged duration as follows: absolute neutrophil counts <500/ micro l lasted 5-12 days in @entity1 who had not previously received transplant and 7-21 days in @entity1 who were post-transplant. Other significant @entity137 included @entity15856 (two CTV-treated @entity1 , one C/I-treated @entity1 ) and @entity2335 (one C/I-treated @entity1 ). Major responses were seen in 4 (15%) of 26 CTV and 4 (17%) of 24 C/I-treated @entity1 with assessable disease. @entity236 resolved in 5 (28%) of 18 CTV-treated @entity1 and in 4 (27%) of 15 C/I-treated @entity1 . 3F8 after CTV or C/I was not blocked by neutralizing antibodies, consistent with the desired immunosuppressive effect of high-dose @entity786 . CONCLUSIONS: CTV and C/I require transfusional and antibiotic support but otherwise entail tolerable morbidity. They have modest antineuroblastoma activity in heavily treated @entity1 and are good preparative regimens for passive immunotherapy with monoclonal antibodies.
