Tags: Drug.
Tirapazamine (SR-4233) is an experimental anticancer drug that is activated to a toxic radical only at very low levels of oxygen (hypoxia). Such levels are common in human solid tumors a phenomenon known as tumor hypoxia. Thus tirapazamine is activated to its toxic form preferentially in the hypoxic areas of solid tumors. Cells in these regions are resistant to killing by radiotherapy and most anticancer drugs.
