Abstract: The invention provides a compound of the formula (I): for use in medicine: or salts or tautomers or N-oxides or solvates thereof; wherein R1 is an optionally substituted heterocyclic group having from 3 to 12 ring members provided that the cyclic group joined to the pyrazole contains at least one heteroatom selected from N, O or S; A is a bond or —Y—(B)n—; B is C?O, NRg(C?O) or O(C?O) wherein Rg is hydrogen or C1-4 hydrocarbyl optionally substituted by hydroxy or C1-4 alkoxy; n is 0 or 1; Y is a bond or an alkylene chain of 1,2 or 3 carbon atoms in length; R2 is hydrogen; halogen; C1-4 alkoxy (e.g. methoxy); or a C1-4 hydrocarbyl group optionally substituted by halogen (e.g. fluorine), hydroxyl or C1-4 alkoxy (e.g. methoxy); R3 is selected from optionally substituted carbocyclic and heterocyclic groups having from 3 to 12 ring members or an optionally substituted C1-8 hydrocarbyl group; with the proviso that R1 is not formula (II): where X, R3? and R4? are defined in the claims.