Questions About Cancer? 1-800-4-CANCER
  • Print
  • Facebook
  • Twitter
  • Google+
  • Pinterest

NCI Drug Dictionary


irinotecan/P-glycoprotein inhibitor HM30181AK combination tablet 
An orally bioavailable combination tablet containing the semisynthetic camptothecin derivative irinotecan and the multidrug resistance (MDR) efflux pump P-glycoprotein (P-gp) inhibitor HM30181AK, with potential antineoplastic activity. HM30181A binds to P-gp and prevents the P-gp-mediated efflux of irinotecan from tumor cells, which may result in greater intracellular concentrations of irinotecan and enhanced cytotoxicity. Retained intracellularly, the prodrug irinotecan is converted, by a carboxylesterase-converting enzyme, to the biologically active metabolite 7-ethyl-10-hydroxy-camptothecin (SN-38). SN-38 inhibits topoisomerase I activity by stabilizing the cleavable complex between topoisomerase I and DNA, resulting in DNA breaks that inhibit DNA replication and trigger apoptotic cell death. P-gp, encoded by the MDR-1 gene, is a member of the ATP-binding cassette (ABC) superfamily of transmembrane transporters and is overexpressed by some MDR tumors, preventing the intracellular accumulation of various cytotoxic agents. Check for active clinical trials or closed clinical trials using this agent. (NCI Thesaurus)
Foreign brand name:Oratecan