Used primarily in the treatment of colorectal cancer, this compound functions as a thymidylate synthase inhibitor, disrupting DNA synthesis in rapidly dividing cancer cells. It is administered intravenously and offers an alternative to 5-fluorouracil-based regimens, particularly in patients who cannot tolerate those therapies. Its targeted mechanism allows for a more specific action on cancer cells, potentially reducing broad systemic toxicity. Treatment cycles are typically spaced every three weeks, allowing bone marrow and gastrointestinal tissues time to recover between doses.