fluorouracil + oxaliplatin + tiopronin

This is a combination regimen consisting of three drugs: - **Fluorouracil (5-FU):** A pyrimidine analog antimetabolite that inhibits thymidylate synthase, disrupting DNA synthesis and leading to cell death, particularly in rapidly dividing cancer cells. - **Oxaliplatin:** A platinum-based chemotherapeutic agent that forms DNA crosslinks, inhibiting DNA replication and transcription, resulting in apoptosis of cancer cells. - **Tiopronin:** A thiol-containing small molecule primarily used to prevent cystine kidney stones by binding cystine. In the context of chemotherapy regimens, tiopronin has been investigated for its potential to reduce chemotherapy-induced hepatotoxicity and improve patient tolerance to regimens such as FOLFOX (fluorouracil + oxaliplatin) by acting as an antioxidant or cytoprotective agent[2][7]. This specific combination is not a standard named regimen but represents an investigational or supportive approach where tiopronin is added to the established fluorouracil plus oxaliplatin backbone. The primary indication for fluorouracil plus oxaliplatin combinations is metastatic colorectal cancer; tiopronin's addition aims at reducing toxicity rather than direct anticancer activity[2][6].