Abstract: Compounds of formula (I) where: X1 is OH or SH or NH2 or —L-Z; X2 and X3 are the same or different and each is H, C1-4 alkyl, benzyl a protecting group or —L-Z, X4 is H or C1-4 alkyl, L is a linker comprising a chain of 0-10 atoms, Z is a group comprising a detectable moiety which comprise at least one detectable moiety are useful in the diagnosis and prognosis and radiotherapy of metastatic bone disease.

Abstract: Compounds of formula (I) where: X1 is OH or SH or NH2 or -L-Z; X2 and X3 are the same or different and each is H, C1-4 alkyl, benzyl a protecting group or -L-Z, X4 is H or C1-4 alkyl, L is a linker comprising a chain of 0-10 atoms, Z is a group comprising a detectable moiety which comprise at least one detectable moiety are useful in the diagnosis and prognosis and radiotherapy of metastatic bone disease.

Abstract: The present invention relates to 32P or 33P-labelled bisphosphonates as radiotherapeutic radiopharmaceuticals. The 32P- or 33P-labelled bisphosphonates, which are chemically identical to the unlabelled agent, are expected to target the lesion site in an identical manner, but also deliver a significant radiocytotoxic effect to the surrounding cells. This should result, given the favorable energetics of the &bgr; particle emission from the 33P nuclide, in a loss of proliferative capacity of cells associated with the tumor lesion. The relative stability and in vivo localisation of bisphosphonates makes them good candidates as 32P/33P delivery vehicles.