technetium Tc 99m oxidronate (Curium)

99mTc-hydroxymethylene diphosphonate (also known as technetium Tc 99m oxidronate) is a diagnostic radiopharmaceutical used in nuclear medicine. It is primarily indicated for skeletal imaging to demonstrate areas of altered osteogenesis, but it has gained significant clinical utility in the noninvasive diagnosis of transthyretin amyloid cardiomyopathy (ATTR-CM). The drug consists of a phosphonate ligand (oxidronate) that complexes with the gamma-emitting radioisotope technetium-99m. Upon intravenous administration, it localizes to bone by adsorbing onto hydroxyapatite crystals, particularly in regions of high bone turnover. In the context of cardiac amyloidosis, it binds to transthyretin amyloid fibrils in the myocardium, enabling visualization and quantification of amyloid burden via SPECT/CT imaging. Recent clinical data suggests it provides equivalent diagnostic yield and potentially superior myocardial-to-blood-pool discrimination compared to 99mTc-pyrophosphate (PYP).

Brand names

Osteoscan-HDP

Other names

99mTc-hydroxymethylene diphosphonatetechnetium Tc 99m hydroxymethylene diphosphonatetechnetium Tc 99m oxidronate