Pharmacology and scheduling of Temozolomide

Temozolomide (TMZ) is an alkylating drug, belonging to the family of derivatives of Imidazotetrazinone. Pre-clinical studies showed that TMZ has a good bioavailability after oral administration and is able to cross the blood-brain barrier. Due to these peculiar pharmaco-dynamic features, TMZ has been first adopted in the treatment of malignant brain tumors. The clinical use of TMZ has shown that the drug has a negligible toxicity and its antitumor activity is “schedule-dependent”. Therefore, many schedules of TMZ administration have been developed in order to investigate and ameliorate its antitumoral efficacy. A higher response rate was detected when the TMZ total dose is administered over 5 days. Recently, the activity of TMZ in combination with different antineoplastic agents is under investigation in children and adults in order to test its activity in malignant tumours other than brain tumors.