S-1 + irinotecan + panitumumab

S-1 + irinotecan + panitumumab is a combination regimen used primarily as a second-line chemotherapy for metastatic colorectal cancer (mCRC) with wild-type KRAS. - **S-1** is an oral fluoropyrimidine derivative composed of tegafur (a prodrug of 5-fluorouracil), gimeracil (a dihydropyrimidine dehydrogenase inhibitor), and oteracil (which reduces gastrointestinal toxicity). Tegafur is converted to 5-FU, which inhibits thymidylate synthase, disrupting DNA synthesis in tumor cells[8][9]. - **Irinotecan** is a topoisomerase I inhibitor that prevents DNA re-ligation during replication, leading to cell death. - **Panitumumab** is a fully human monoclonal antibody targeting the epidermal growth factor receptor (EGFR), blocking ligand binding and downstream signaling pathways involved in cell proliferation and survival[5]. This regimen has demonstrated acceptable toxicity and promising efficacy in patients with previously treated wild-type KRAS mCRC, with response rates around 33% and median progression-free survival of approximately 9.5 months[1][3][4].

Other names

IRIS plus panitumumab