OncoTherapy Science Inc. has developed a chimeric humanized monoclonal antibody (mAb) against FZD10, named OTSA101. Non-radiolabeled OTSA101 antibody has only weak antagonistic activity on SS cell growth. However, Yttrium 90-radiolabeled OTSA101 (OTSA101-DTPA-90Y) showed significant antitumor activity following a single intravenous injection in mouse xenograft model.