Theranostic compounds

A hydroxamate metalloprotease inhibitor compound for use in a method of diagnosing or treating cancer, inflammatory diseases, or Alzheimer's disease, comprising a zinc-chelating N-hydroxylamine moiety radiolabelled with a radionuclide is provided, wherein the compound has the structure: wherein R1 and R6 are alkyl groups; R2 and R4 are an alkyl, alkenylene, alkynylene, or aryl group; and R3 and R5 are H or lower alkyl groups. The compound may be (2R,3S)-3-(formylhydroxyamino)-2-(3-phenyl-1-propyl)butanoic acid [(1S)-2,2-dimethyl-1-(methylcarbamoyl)-1-propyl]amide (GI254023X) or a derivative thereof. The compound may be for use in targeted radionuclide therapy wherein a patient is treated with a compound comprising a diagnostic radionuclide to identify the presence of a disease, followed by treatment with a compound comprising a therapeutic radionuclide to treat the disease. The diagnostic radionucleotide label to identify the disease using SPECT may be 123I, while 124I may be used for PET imaging. The therapeutic radionuclide for injecting into a patient for therapy may be 125I or 131I. The cancer may be cervical or oesophageal cancer or glioblastoma. A method of preparing the radiolabelled compound by SEAr radio-iodination of an aromatic ring of the compound or a precursor using radiolabelled sodium iodide with N-chlorosuccinimide in trifluoroacetic acid is provided.