Compounds of Formula (I): wherein W is NR 1A or CR 1B R 1B ; Z is N or CH; R 1A is C 1 -C 3 alkyl, C 1 -C 3 haloalkyl C 3 -C 4 cycloalkyl or phenyl wherein cycloalkyl or phenyl is optionally mono-, di- or tri-substituted with substituents each independently selected from C 1 - C 3 alkyl, halo, amino and C 1 -C 3 alkoxy; the two R 1B together with the carbon atom to which they are attached combine and form C 3 -C 6 cycloalkyl or heterocyclyl, wherein the cycloalkyl is substituent with C(=O)OR 1C , NHC(=O)OR 1C or NHS(=O) 2 R 1C , and the heterocyclyl is substituent with C(=O)R 1C , C(=O)OR 1C , S(=O) 2 R 1C , C(=O)NH 2 or C(=O)NR 1C R 1C' ; n is 0, 1 or 2; n, q, R 1C , R 1C ', R 2 and R 3 are as defined herein, their use as inhibitors of RSV and related aspects.