Irinotecan-d₁₀is intended for use as an internal standard for the quantification of irinotecan by GC- or LC-MS. Irinotecan, a derivative of the alkaloid camptothecin , functions as a prodrug that is converted by tissue carboxylesterase to 7-ethyl-10-hydroxycamptothecin, a potent inhibitor of DNA topoisomerase I.^1,2Its action is terminated by glucuronidation by UDP glucuronosyl transferase 1A1.^3,4Formulations containing irinotecan demonstrate broad spectrum antitumor activity against metastatic colorectal cancer, small cell lung cancer, and several other solid tumors and have proven useful in radiation treatment of tumors by sensitizing tissue to radiation damage.^1,2

1.Rothenberg, M.L.Topoisomerase I inhibitors: Review and updateAnn. Oncol.8(9)837-855(1997) 2.Dancey, J., and Eisenhauer, E.A.Current perspectives on camptothecins in cancer treatmentBr. J. Cancer74(3)327-338(1996) 3.Mathijssen, R.H.J., van Alphen, R.J., Verweij, J., et al.Clinical pharmacokinetics and metabolism of irinotecan (CPT-11)Clin. Cancer Res.7(8)2182-2194(2001) 4.Ma, M.K., and McLeod, H.L.Lessons learned from the irinotecan metabolic pathwayCurr. Med. Chem.10(1)41-49(2003)