213Bi-PAI2

213Bi-PAI2 is a targeted radiopharmaceutical conjugate consisting of the alpha-emitting radioisotope **Bismuth-213 (213Bi)** chelated to **plasminogen activator inhibitor-2 (PAI2)**. PAI2 is a recombinant protein that selectively binds the cell-surface receptor urokinase plasminogen activator (**uPA**), a marker implicated in the metastatic spread of cancer cells. Upon binding, the alpha particle emission from 213Bi delivers highly cytotoxic radiation directly to uPA-expressing tumor cells, causing apoptosis and tumor regression while sparing nearby normal tissue. 213Bi-PAI2 has demonstrated potent activity against breast cancer[2][5], prostate cancer[3], and pancreatic cancer[4] in preclinical models, with pronounced efficacy in suppressing micrometastatic disease and minimal off-target toxicity. The modality leverages the short range and high linear energy transfer of alpha particles to maximize tumor cell kill. Developed as a novel form of **targeted alpha therapy (TAT)**, 213Bi-PAI2 is proposed primarily for the treatment and control of micrometastases in cancers expressing uPA.

Brand names

213Bi-PAI2

Other names

213Bi-plasminogen activator inhibitor type 2213Bi-PAI2 conjugate213Bi labeled PAI2