117mSn-DOTA-Annexin V (or 117mSn-Annexin, Tin-Annexin) is a natural protein labeled with Tin-117m that can be used to both image and treat (demonstrated in animal trials) vulnerable plaque, cancers or rheumatoid arthritis.

There is currently no way to predict major problems, such as a heart attack or stroke, linked to the rupture of such plaques in human vessels. This tracer would be able to completely modify the follow-up of patients at risk. Moreover, if it is confirmed that the therapeutic effect of 117mSn helps “dissolving” such plaques, this product has the potential to be a blockbuster.

This theranostic agent is also under development in Alzheimer therapy with the target aging microglia that could be destroyed the same way macrophages can be targeted in infected cells.

The drug is in clinical Phase II. The ongoing study performed on carotid endarterectomy subjects (dose of 3 mCi) confirmed the imaging of vulnerable plaques (histopathology as reference modality). Aortic aneurism was imaged and confirmed by CT scan. No new results have been published recently. Funds are missing to resume the studies.