Oral delivery of anticancer drugs I: general considerations.

Historically, most of anticancer drugs were delivered by the intravenous route which is the most direct one leading to immediate and complete bioavailability of the drugs. However, this administration route could result in several side effects and requires a clinic or hospitalization visit, nursing and palliative treatment. For these latter reasons, oral delivery of anticancer drugs is nowadays more and more considered, including already marketed drugs. In this first review, we aim to identify general considerations for the oral delivery of anticancer drugs. In the second and the third reviews we respectively discuss the prodrug strategy and the use of drug delivery systems to improve the oral bioavailability of anticancer drugs.