Tropisetron (Navoban-Sandoz) and Ondansetron (Zofron-Glaxo) are selective serotonin (5-HT3) antagonists that have proven very effective in the prevention of vomiting and nausea in adults and children receiving chemotherapy for solid tumors and blood malignancies. The purpose of this study was the comparison of efficacy of the two agents in the prevention of acute vomiting and nausea. We studied 23 children (11 children with ALL, 3 with neuroblastoma, 2 with Wilm's tumor, 2 with NHL, 2 with Hodgkin's disease, 1 child with ovarian germ cell tumor and 1 with rabdomyosarcoma) in 177 chemotherapeutic cycles (116 one day, 61 multiple day cycles). In 104 cycles the children received as antiemetic agent ondansetron in a dose of 5 mg/m2 30 min before chemotherapy was given and then 4 mg/m2 every 8 hours IV (group A) and in 73 cycles they received tropisetron (group B) in a dose of 0,2 mg/kg IV (max dose 5 mg) every day they received chemotherapy. The response was defined as “complete”: in the absence of nausea and vomiting per 24 hours of chemotherapy, as“partial” in the presence one to four events of vomiting and/or nausea less than 5 hours per 24 hours and “failure”: the experience of five or more events of vomiting and/or more than five hours of nausea per 24 hours of chemotherapy. We studied the response of the two groups depending and independing on the degree of emetogenicity of the chemotherapeutic agents which were devided into mild, moderate and high one day and multiple day cycles seperately. The results showed that although both antiemetic agents are equally effective in multiple day cycles (p=0,2) concerning complete, partial response and treatment failure ondansetron is more effective in the control of nausea and vomiting with statistical significance (p=0,023) in one day cycles and independed of the emetogenicity of cytotoxic drugs. The statistical analysis depending on the emetogenicity of chemotherapeutic agents showed greater efficacy of ondansetron in moderate(p=0,001) and mild (p=0,017) emetogenic drugs whereas there was no difference in the highly emetogenic drugs' group. In conclusion the two antiemetic agents are equally effective independing emetogenicity of chemotherapeutic agents in multiple day cycles, although ondansetron has proven more effective when mild and moderate emetogenic drugs are administered.
