Derivatives of pyridinyl and pyrimidinyl substituted as modulators of metabolism and treatment of disorders related thereto.

Composition comprising: (a) an inhibitor of dipeptidyl peptidase IV (DPP-IV); and (b) a compound selected from compounds of Formula (Ia) compound and salts, pharmaceutically acceptable solvates and hydrates thereof: ** (See formula) ** wherein X is N or CR8, wherein R8 is H or halogen; Y is NH or O; Z is CH or N; R1 is carbo-C1-8 it alkoxy, oxadiazolyl or pyrimidinyl, wherein said carbo-in C1-6 alkoxy, oxadiazolyl and pyrimidinyl are each optionally substituted with 1 or 2 substituents independently selected from: C1-4 alkyl, C1-4 alkoxy and C3-5 cycloalkyl; R2 is H or C1-4 alkyl; R3 is C1-4 alkoxy, O-C2-4-alkynyl, or hydroxyl; R4 is selected from: H, C1-4 alkoxy, C1-4 alkyl, C2-4 alkynyl and halogen; R5 is selected from: C1-4 acylsulfonamide, C1-4 alkoxy, C1-4 alkyl, C1-4 alkylamino, C1-4alquilsulfonil, C1-4 alkylthio, cyano, heterocyclyl, di-C1-4-dialkylamino and sulfonamide, in wherein said C 1-4 alkoxy, C 1-4 alkyl, C 1-4 alkylamino, C1-4alquilsulfonil, C1-4alquiltio, di-C1-4-dialkylamino and heterocyclyl are each optionally substituted with 1 or 2 substituents independently selected from: C2-4 alkynyl, C 1-4 alkoxy, C1-4alquilcarboxamida, C1-4 alkylsulfonyl, C3-5cicloalquil, C3-5 cycloalkyloxy, diC1-4- alkylcarboxamide, hydroxyl and phosphonooxy, wherein said optionally substituted C1-4 alkylcarboxamide is hydroxyl; or R5 is a group of Formula (A): ** (See formula) ** wherein "m", "n" and "q" are each independently 0, 1, 2 or 3; "R" is 0, 1, or 2; and "t" is 0 or 1; R6 is H or halogen; and R7 is H or C1-4 alkyl.