The invention concerns the use of a quinazoline derivative of Formula (I) wherein Q
1
includes a quinazoline ring optionally substituted with a group such as halogeno, trifluoromethyl and cyano, or a group of the formula: Q
3
—X
1
— wherein X
1
includes a direct bond and O and Q
3
includes aryl, aryl-(1-6C)alkyl, heterocyclyl and heterocyclyl-(1-6C)alkyl; each of R
2
and R
3
is hydrogen or (1-6C)alkyl; Z includes O, S and NH; and Q
2
includes aryl and aryl-(1-3C)alkyl or a pharmaceutically-acceptable salt thereof, in the manufacture of a medicament for use in the production of an antiangiogenic and/or vascular permeability reducing effect in a warm-blooded animal such as a human.
1