99mTc-annexin A5

**99mTc-annexin A5** is a radiopharmaceutical consisting of annexin A5, a human protein with high affinity for phosphatidylserine, labeled with the radionuclide technetium-99m. It is designed as a molecular imaging agent for the in vivo detection of apoptosis, as phosphatidylserine is externalized on the surface of apoptotic cells. Several formulations exist (e.g., 99mTc-HYNIC-annexin A5, 99mTc-C3(BHam)2-annexin A5, 99mTc-tricarbonyl-His6-annexin A5), optimized for biodistribution or imaging characteristics. The primary clinical application is non-invasive SPECT imaging to assess apoptotic activity in tumors, especially to monitor or predict response to chemotherapy or radiotherapy. 99mTc-annexin A5 enables early and quantitative assessment of treatment efficacy, with high specificity in identifying apoptotic cell populations in vivo[2][3][5][1][4][6][7].

Other names

technetium-99m annexin A5technetium99m annexin A5technetium 99m annexin A599mTc-annexin V