The invention provides a compound of the formula (I) for use in the prophylaxis or treatment of a disease state or condition mediated by a cyclin dependent kinase: wherein A is a group R2 or CH2—R2 where R2 is a carbocyclic or heterocyclic group having from 3 to 12 ring members; B is a bond or an acyclic linker group having a linking chain length of up to 3 atoms selected from C, N, S and O; R1 is hydrogen or a group selected from SO2Rb, SO2NR7R8, CONR7R8, NR7R9 and carbocyclic and heterocyclic groups having from 3 to 7 ring members; R3, R4, R5 and R6 are the same or different and are each selected from hydrogen, halogen, hydroxy, trifluoromethyl, cyano, nitro, carboxy, amino, carbocyclic and heterocyclic groups having from 3 to 12 ring members; a group Ra—Rb wherein Ra is a bond, O, CO, X1C(X2), C(X2)X1, X1C(X2)X1, S, SO, SO2, NRc, SO2NRc or NRcSO2; and Rb is selected from hydrogen, carbocyclic and heterocyclic groups having from 3 to 12 ring members, and a C1-8 hydrocarbyl group optionally substituted by one or more substituents selected from hydroxy, oxo, halogen, cyano, nitro, amino, mono- or di-C1-4 hydrocarbylamino, carbocyclic and heterocyclic groups having from 3 to 12 ring members and wherein one or more carbon atoms of the C1-8 hydrocarbyl group may optionally be replaced by O, S, SO, SO2, NRc, X1C(X2), C(X2)X1 or X1C(X2)X1; Rc is hydrogen or C1-4 hydrocarbyl; X1 is O, S or NRc and X2 is ═O, ═S or ═NRc; R7 is selected from hydrogen and a C1-8 hydrocarbyl group optionally substituted by one or more substituents selected from hydroxy, oxo, halogen, cyano, nitro, amino, mono- or di-C1-4 hydrocarbylamino, carbocyclic and heterocyclic groups having from 3 to 12 ring members and wherein one or more carbon atoms of the C1-8 hydrocarbyl group may optionally be replaced by O, S, SO, SO2, NRc, X1C(X2), C(X2)X1 or X1C(X2)X1; R8 is selected from R7 and carbocyclic and heterocyclic groups having from 3 to 12 ring members; R9 is selected from R8, COR8 and SO2R8; or NR7R8 or NR7R9 may each form a heterocyclic group having from 5 to 12 ring members; but excluding the compounds N-[(morpholin-4-yl)phenyl-1H-indazole-3-carboxamide and N-[4-(acetylaminosulphonyl)phenyl-1H-indazole-3-carboxamide.