ZD1839 (Iressa) modifies the activity of key enzymes linked to fluoropyrimidine activity: rational basis for a new combination therapy with capecitabine.

Abstract

These data demonstrate a strong synergistic interaction between ZD1839 and 5'-DFUR when ZD1839 is applied before or concurrently with 5'-DFUR. Such a drug combination would have two advantages: (a) the theoretical advantage of tumor selectivity of epidermal growth factor receptor-targeted therapy; and (b) the practical advantage of a combination therapy that could be administered p.o.