A compound of formula: wherein: X is nitrogen or -CH-; U is CH, CH2, or CMe; Y is CH, CF, or O; indicate a single or a double bond; R1a, R1b are each independently hydrogen, an optionally substituted straight or branched (C1-C6)alkyl, or together with the atom to which they are bound, may form a (C3-C6)cycloalkyl; A is a (C3-C6)cycloalkyl, aryl or heteroaryl; R4 is hydrogen, halogen, cyano or an optionally substituted straight or branched (C1-C6) alkyl; R5a and R5b are each independently a group selected from an optionally substituted straight or branched (C1-C6)alkyl, (C3-C6)cycloalkyl, or together with the atom to which they are bound, may form a 3 to 7 membered cyclylalkyl or heterocyclyl group containing one heteroatom selected from O, S, N-R6; wherein: R6 is an optionally substituted straight or branched (C1-C6) alkyl, -COOR7 or -COR8; wherein: R7 and R8 are an optionally substituted straight or branched (C1-C6)alkyl; M is a bond, NH, NR6 or O, wherein R6 is as defined above; G1is N, CH, CH2 or CO; Z1 is CR9aR9b; Z2 is CR10aR10b; wherein: R9a, R9b, R10a and R10b are independently hydrogen or an optionally substituted straight or branched (C1-C6) alkyl; m1 is 1, 2 or 3; m2 is 0, 1, 2 or 3; E is CN, or an optionally substituted straight or branched (C1-C6)alkyl, (C2-C6)alkenyl, (C2-C6)alkynyl; R2 is an optionally substituted group selected from straight or branched (C1-C6)alkyl, (C3-C6)cycloalkyl-(C1-C6)alkyl, aryl-(C1-C6)alkyl, and heterocyclyl-(C1-C6)alkyl; R3 is hydrogen, chloro, cyano, CONH2, NH2, NR12aR12b, OR13, or an optionally substituted group selected from straight or branched (C1-C6)alkyl, (C3-C6)cycloalkyl-(C1-C6)alkyl, aryl and heteroaryl; wherein: R12a, R12b are each independently selected from hydrogen or optionally substituted straight or branched (C1-C6)alkyl; R13 is an optionally substituted straight or branched (C1-C6)alkyl; or a pharmaceutically acceptable salt thereof. X is nitrogen or -CH-; U is CH, CH2, or CMe; Y is CH, CF, or O; indicate a single or a double bond; R1a, R1b are each independently hydrogen, an optionally substituted straight or branched (C1-C6)alkyl, or together with the atom to which they are bound, may form a (C3-C6)cycloalkyl; A is a (C3-C6)cycloalkyl, aryl or heteroaryl; R4 is hydrogen, halogen, cyano or an optionally substituted straight or branched (C1-C6) alkyl; R5a and R5b are each independently a group selected from an optionally substituted straight or branched (C1-C6)alkyl, (C3-C6)cycloalkyl, or together with the atom to which they are bound, may form a 3 to 7 membered cyclylalkyl or heterocyclyl group containing one heteroatom selected from O, S, N-R6; wherein: R6 is an optionally substituted straight or branched (C1-C6) alkyl, -COOR7 or -COR8; wherein: R7 and R8 are an optionally substituted straight or branched (C1-C6)alkyl; M is a bond, NH, NR6 or O, wherein R6 is as defined above; G1is N, CH, CH2 or CO; Z1 is CR9aR9b; Z2 is CR10aR10b; wherein: R9a, R9b, R10a and R10b are independently hydrogen or an optionally substituted straight or branched (C1-C6) alkyl; m1 is 1, 2 or 3; m2 is 0, 1, 2 or 3; E is CN, or an optionally substituted straight or branched (C1-C6)alkyl, (C2-C6)alkenyl, (C2-C6)alkynyl; R2 is an optionally substituted group selected from straight or branched (C1-C6)alkyl, (C3-C6)cycloalkyl-(C1-C6)alkyl, aryl-(C1-C6)alkyl, and heterocyclyl-(C1-C6)alkyl; R3 is hydrogen, chloro, cyano, CONH2, NH2, NR12aR12b, OR13, or an optionally substituted group selected from straight or branched (C1-C6)alkyl, (C3-C6)cycloalkyl-(C1-C6)alkyl, aryl and heteroaryl; wherein: R12a, R12b are each independently selected from hydrogen or optionally substituted straight or branched (C1-C6)alkyl; R13 is an optionally substituted straight or branched (C1-C6)alkyl; R12a, R12b are each independently selected from hydrogen or optionally substituted straight or branched (C1-C6)alkyl; R13 is an optionally substituted straight or branched (C1-C6)alkyl; or a pharmaceutically acceptable salt thereof.