Answer
Irinotecan and its more active metabolite SN-38 inhibit DNA topoisomerase I, inducing single-strand DNA lesions that block DNA replication forks and cause time-dependent cytotoxicity specific to the S phase.
Sources for this answer
- Campto 20mg/ml concentrate for solution for infusion (40mg presentation)Pfizer Limited · emc · SmPC §5.1 Pharmacodynamic properties · Version 27Document updated
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