A compound of formula (I), ** Formula ** its pharmaceutically acceptable salts, pharmaceutically acceptable solvates or stereoisomers thereof, wherein A is ** Formula ** X1 is CH or N； R1 represents hydrogen or -C1-C6 alkyl； R2 is independently selected from hydrogen, halogen, cyano, -C1-C6 alkyl, C1-C6 haloalkyl, C1-C6 haloalkoxy, phenyl optionally substituted with 1 to 3 halogens or an optionally substituted -O-heterocyclyl wherein the optional substituent is selected between alkyl, -ORi or -C (O) N (Ri) 2； when X1 is CH, optionally two R2 present in two adjacent carbon atoms combine to form a 5- to 7-membered heterocyclic ring； R3 is independently selected from halogen, cyano, -ORi, -C (O) N (Ri) 2 or two R3 together with the carbon atom to which they are attached form a C3-C7 spirocycloalkyl group anchored to pyrrolidine； or two R3 when attached to adjacent carbon atoms form a C3-C7 cycloalkyl ring fused to pyrrolidine； Ra is selected from (i) a group selected from -C1-C6 alkyl, C1-C6 hydroxyalkyl or optionally substituted C1-C6 alkoxy where the optional substituent is selected from cyano, halogen or C6 -aryl -C12, (ii) an optionally substituted C3-C10 -cycloalkyl wherein the optional substituent is selected from cyano, -C1-C6 alkyl, hydroxyl, halogen or -Rs, (iii) an optionally substituted C6-C12 -aryl wherein the optional substituent is selected from cyano, hydroxyl, halogen, -C1-C6 alkyl or -Rr (iv) an optionally substituted 5-10 membered heterocyclyl wherein the optional substituent is selected from cyano, hydroxyl, halogen or -C1-alkyl C6, (v) an optionally substituted 5 to 10 membered heteroaryl wherein the optional substituent is selected from cyano, oxo (>； = O), hydroxyl, halogen, -C1-C6 alkyl, -C1-C6 alkoxy, -NRcRd or -Rr, (vi) -NR4R5, (vii) -C1-C6 alkyl-C6-C12 aryl； Rb represents hydrogen or halogen； R4 is selected from hydrogen, -C1-C6 alkyl, -C3-C10 cycloalkyl, -C1-C6 hydroxyalkyl, C1-C6 alkoxyalkyl, C1-C6 halogenoalkyl or (C1-C6) alkyl-C3-C10 alk
