P450-based GDEPT has several advantages: 1) P450 is a multiple enzyme-multiple drug system, unlike other GDEPT systems, which are essentially one enzyme-one drug systems [8-11]; 2) P450 GDEPT can be implemented using established anti-cancer agents, such as CPA and ifosfamide, as well as investigational agents, such as the CYP3A4 prodrug methoxymorpholinyl doxorubicin [12], the CYP1A2 prodrug dacarbazine [13], 4-ipomeanol, ftorafur, and tamoxifen, among others [7,8]. Here, CYP2B6 is linked to cancer.