Medline ® Abstract for Reference 160
Modulation of irinotecan-induced diarrhea by cotreatment with neomycin in cancer patients.
Kehrer DF, Sparreboom A, Verweij J, de Bruijn P, Nierop CA, van de Schraaf J, Ruijgrok EJ, de Jonge MJ
Clin Cancer Res. 2001;7(5):1136.
This study was designed to evaluate irinotecan (CPT-11) disposition and pharmacodynamics in the presence and absence of the broad-spectrum antibiotic neomycin. Seven evaluable cancer patients experiencing diarrhea graded>or =2 after receiving CPT-11 alone (350 mg/m(2) i.v. once every 3 weeks) received the same dose combined with oral neomycin at 1000 mg three times per day (days -2 to 5) in the second course. Neomycin had no effect on the systemic exposure of CPT-11 and its major metabolites (P>or = 0.22). However, it changed fecal beta-glucuronidase activity from 7.03 +/- 1.76 microg/h/mg (phenolphthalein assay) to undetectable levels and decreased fecal concentrations of the pharmacologically active metabolite SN-38. Although neomycin had no significant effect on hematological toxicity (P>0.05), diarrhea ameliorated in six of seven patients (P = 0.033). Our findings indicate that bacterial beta-glucuronidase plays a crucial role in CPT-11-induced diarrhea without affecting enterocycling and systemic SN-38 levels.
Department of Medical Oncology, Rotterdam Cancer Institute, Daniel den Hoed Kliniek and University Hospital Rotterdam, 3075 EA Rotterdam, the Netherlands. firstname.lastname@example.org