SN-38 is the active
metabolite
of
irinotecan
(an analog of
camptothecin
- a
topoisomerase I
inhibitor); it is 200 times more active than
irinotecan itself.
SN38 is metabolized via glucoronidation by
UGT1A1.The variant of UGT1A1 in ~10% of Caucasians which leads to poor metabolization of
Irinotecan predicts Irinotecan toxicity, as it cannot be excreted from the body in its SN-38 form.SN-38 is lost into the bile and feces. It can cause the symptoms of
diarrhoea and myelosuppression experienced by ~25% of the patients administered Irinotecan.
Chemical
Structure
%20.gif)
Molecular Formula C22H20N2O5