The invention relates to quinazoline derivatives of formula (I), wherein m is an integer from 1 to 3; R1 represents halogeno or C1-3alkyl; X1 represents —O—; R2 is selected from one of the following three groups: 1) C1-5alkylR3 (wherein R3 is piperidinyl-4-yl which may bear one or two substituents selected from hydroxy, halogeno, C1-4alkyl, C1-4hydroxyalkyl and C1-4alkoxy; 2) C2-5alkenylR3 (wherein R3 is as defined hereinbefore); 3) C2-5alkynylR3 (wherein R3 is as defined hereinbefore); and wherein any alkyl, alkenyl or alkynyl group may bear one or more substituents selected from hydroxy, halogeno and amino; and salts thereof; processes for their preparation, pharmaceutical compositions containing a compound of formula (I) or a pharmaceutically acceptable salt thereof as active ingredient. The compounds of formula (I) and the pharmaceutically acceptable salts thereof inhibit the effects of VEGF, a property of value in the treatment of a number of disease states including cancer and rheumatoid arthritis.