5-fluorouracil + irinotecan + rofecoxib

This is a combination regimen consisting of three drugs: - **5-fluorouracil (5-FU):** A pyrimidine analog antimetabolite that inhibits thymidylate synthase, disrupting DNA synthesis and function, primarily used as chemotherapy for various cancers including colorectal cancer[8]. - **Irinotecan:** A topoisomerase I inhibitor that prevents DNA unwinding and replication, leading to cell death. It is commonly used in combination with 5-FU for the treatment of metastatic colorectal cancer[3][4][1]. - **Rofecoxib:** A selective cyclooxygenase-2 (COX-2) inhibitor nonsteroidal anti-inflammatory drug (NSAID), which reduces inflammation and pain by inhibiting prostaglandin synthesis. Rofecoxib was withdrawn from the market due to increased cardiovascular risk but has been studied in oncology settings for its potential to modulate tumor microenvironment and reduce chemotherapy-induced side effects[7][9][1]. This specific combination has been investigated in clinical trials as a treatment regimen for advanced or metastatic colorectal cancer. The rationale includes combining cytotoxic agents (irinotecan and 5-FU) with an anti-inflammatory agent (rofecoxib) to potentially enhance anticancer efficacy or tolerability[1]. Rofecoxib's use is experimental/off-label in this context due to its withdrawal from general medical use.