Vantictumab is a humanized monoclonal antibody targeting Frizzled receptors (FZD1, 2, 5, 7, 8), key components of the Wnt signaling pathway. It binds to multiple FZD receptors to inhibit Wnt/β-catenin signaling, which is often dysregulated in cancers. It was investigated for the treatment of solid tumors, such as pancreatic and breast cancers, but clinical development was discontinued due to bone-related toxicity and limited efficacy.