227Th-Anetumab (227Th-BAY2287411) is a mesothelin targeted thorium conjugate (MSLN-TTC) consisting of a monoclonal antibody (anetumab) covalently linked via an amide bond to a chelator moiety (3,2-HOPO) possessing high affinity for the alpha-emitting nuclide Thorium-227.

Anetumab is a human immunoglobulin G1 (IgG1) monoclonal antibody. 227Th-BAY2287411 should become a therapeutic agent directed at solid tumors expressing mesothelin. First priority is given to ovarian cancer. For imaging purpose the analogue 89Zr labeled tracer was also synthesized.

A clinical study of 227Th-BAY2287411 was initiated in patients with tumors known to express mesothelin. This study involving 228 participants is expected to be completed by end of 2023.