Patent ID: 8188296

Claim:
A stabilised radiopharmaceutical composition which comprises: (i) a synthetic, non-peptide compound which targets a site within the mammalian body when administered in vivo which is labelled with 123 I, where the 123 I is covalently attached to a phenyl group or a vinyl group of the synthetic compound; (ii) a stabiliser which comprises gentisic acid or a salt thereof with a biocompatible cation in an amount effective to stabilise said 123 I-labelled synthetic compound against radiolysis; (iii) an aqueous biocompatible carrier medium; wherein the radioactive concentration of the 123 I in the medium is in the range 8 to 1000 MBq/cm 3 and the pH of the biocompatible carrier medium is in the range 4.5 to 8.5; with the proviso that when the synthetic compound which targets a site within the mammalian body is meta-iodobenzylguanidine, the pH of the biocompatible carrier medium is in the range 5.0 to 8.5.