A compound of formula or a pharmacautically acceptable salt thereof; wherein W is N or CH; X is N or CR 1; Y is N or CR 2; Z is N or CR 3; at least one and at most two of W, X, Y and Z are N; R 1 is H, halogen, S 2 C1-C3 alkyl, cyano, or C1-C3 alkyl optionally substituted with one or more halogen(s); R 2 is H, halogen, cyano, C OH, C OC1-C3 alkyl, C1-C3 alkyl optionally substituted with one or more F; hydroxy-C1-C3 alkyl, S 2 C1-C3 alkyl, S 2 C3-C6 cycloalkyl or S 2 C1-C3 hydroxyalkyl; R 3 is H, halogen or cyano; V is (CHR 4) m; m is 0 or 1; R 4 is H or C1-C3 alkyl optionally substituted with one or more halogen(s); Ar is R 5 is H, halogen or cyano; R 6 is H or halogen; R 7 is H, halogen, C1-C3 alkyl, cyano, S 2 C1-C3 alkyl, or phenyl; R 8 is H, halogen, C1-C3 alkyl optionally substituted with one or more F; C1-C3 alkoxy optionally substituted with one or more F; phenoxy, NHR 11, or NR 11 R 12; R 9 is H, halogen, cyano, C1-C3 alkyl optionally substituted with one or more F; C1-C3 alkylthio optionally substituted with one or more F; C1-C3 alkoxy optionally substituted with one or more F; or C NR 13 R 14; R 10 is H, halogen, cyano, C1-C3 alkyl optionally substituted with one or more F; C1-C3 alkylthio optionally substituted with one or more F; C1-C3 alkoxy optionally substituted with one or more F; or C NR 13 R 14; R 11 is C1-C3 alkyl; R 12 is C1-C3 alkyl; or R 11 and R 12, together with the nitrogen atom to which they are both attached, form a ring of formula R 13 is H or C1-C3 alkyl; and R 14 is H or C1-C3 alkyl; provided that the compound is not selected from 3,4-difluoro-N-(2-hydroxypyridin-3-yl)benzene-1-sulfonamide, N-[5-bromo-3-hydroxypyridin-2-yl]-4-methylbenzenesulfonamide, N-(1,2-dihydro-2-oxo-3-pyridinyl)-2-(trifluoromethyl)-benzenesulfonamide, 4-chloro-N-(1,2-dihydro-2-oxo-3-pyridinyl)-3-(trifluoromethyl)-benzenesulfonamide, 4-chloro-N-(3-hydroxy-2-pyridinyl)-benzenesulfonamide, 3-trifluoromethyl-N-(3-hydroxy-2-pyridinyl)-benzenesulfonamide, 4-methyl-N-(3-hydroxy-2-pyridinyl)-benzenesulfonamide, 4-methyl-N-(2-hydroxy-3-pyridinyl)-benzenesulfonamide, and 4-methyl-N-(2,3-dihydro-3-oxo-4-pyridazinyl)-benzenesulfonamide or its tautomer 4-methyl-N-(3-hydroxy-4-pyridazinyl)-benzenesulfonamide. W is N or CH; X is N or CR 1; Y is N or CR 2; Z is N or CR 3; at least one and at most two of W, X, Y and Z are N; R 1 is H, halogen, S 2 C1-C3 alkyl, cyano, or C1-C3 alkyl optionally substituted with one or more halogen(s); R 2 is H, halogen, cyano, C OH, C OC1-C3 alkyl, C1-C3 alkyl optionally substituted with one or more F; hydroxy-C1-C3 alkyl, S 2 C1-C3 alkyl, S 2 C3-C6 cycloalkyl or S 2 C1-C3 hydroxyalkyl; R 3 is H, halogen or cyano; V is (CHR 4) m; m is 0 or 1; R 4 is H or C1-C3 alkyl optionally substituted with one or more halogen(s); Ar is R 5 is H, halogen or cyano; R 6 is H or halogen; R 7 is H, halogen, C1-C3 alkyl, cyano, S 2 C1-C3 alkyl, or phenyl; R 8 is H, halogen, C1-C3 alkyl optionally substituted with one or more F; C1-C3 alkoxy optionally substituted with one or more F; phenoxy, NHR 11, or NR 11 R 12; R 9 is H, halogen, cyano, C1-C3 alkyl optionally substituted with one or more F; C1-C3 alkylthio optionally substituted with one or more F; C1-C3 alkoxy optionally substituted with one or more F; or C NR 13 R 14; R 10 is H, halogen, cyano, C1-C3 alkyl optionally substituted with one or more F; C1-C3 alkylthio optionally substituted with one or more F; C1-C3 alkoxy optionally substituted with one or more F; or C NR 13 R 14; R 11 is C1-C3 alkyl; R 12 is C1-C3 alkyl; or R 11 and R 12, together with the nitrogen atom to which they are both attached, form a ring of formula R 13 is H or C1-C3 alkyl; and R 14 is H or C1-C3 alkyl; provided that the compound is not selected from 3,4-difluoro-N-(2-hydroxypyridin-3-yl)benzene-1-sulfonamide, N-[5-bromo-3-hydroxypyridin-2-yl]-4-methylbenzenesulfonamide, N-(1,2-dihydro-2-oxo-3-pyridinyl)-2-(trifluoromethyl)-benzenesulfonamide, 4-chloro-N-(1,2-dihydro-2-oxo-3-pyridinyl)-3-(trifluoromethyl)-benzenesulfonamide, 4-chloro-N-(3-hydroxy-2-pyridinyl)-benzenesulfonamide, 3-trifluoromethyl-N-(3-hydroxy-2-pyridinyl)-benzenesulfonamide, 4-methyl-N-(3-hydroxy-2-pyridinyl)-benzenesulfonamide, 4-methyl-N-(2-hydroxy-3-pyridinyl)-benzenesulfonamide, and 4-methyl-N-(2,3-dihydro-3-oxo-4-pyridazinyl)-benzenesulfonamide or its tautomer 4-methyl-N-(3-hydroxy-4-pyridazinyl)-benzenesulfonamide.