Case Study: Amifostine: (Ethyol®)
Amifostine is a prodrug of its free thiol, active metabolite, WR-1065. The thiophosphate promoiety protects the free thiol group of WR-1065 from oxidation to the symmetrical disulfide, WR-33278, while providing a handle for high levels of WR-1065 production at the target tissue. The thiophosphate promoiety of amifostine is cleaved by alkaline phosphatase to produce WR-1065, which accumulates in non-cancerous tissues to a greater extent than in cancerous tissues (Capizzi, 1996).
KeywordsRadiat Oncol Biol Phys Product Insert Mixed Disulphide Thiophosphoric Acid Radiation Oncology Biol Phys
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