Irinotel anti cancer injection from sun contains irinotecan.irinotel is a topoisomerase 1 inhibitor, which prevents dna from unwinding. Chemically, it is a semisynthetic analogue of the natural camptothecin. Its main use is in colon cancer, particularly in combination with other chemotherapy agents. This includes the regimen folfiri which consists of infusional 5-fluorouracil, leucovorin, and irinotecan.