Conjugation and characterization of a new prostate cancer theranostic radiopharmaceutical

The second cause of tumor deaths in adult men is the prostate cancer (PCa). Although radical prostatectomy and local radiotherapy are largely successful for patients with localized cancer, available treatments for metastatic have demonstrated weak curative efficacy. Nowadays, the murine mAb 111In-capromab pendetide (ProstaScint®) is the only product that has been approved by the Food and Drug Administration (FDA) as diagnostic radiopharmaceutical for PCa. ProstaScint® showed promising results in clinical diagnosis, but as a whole antibody exhibits low tumor targeting with a maximum uptake at 6-7 days post-injection and slow clearance from non-target tissues. Recently, it was proved that the anti-PSMA single-chain variable fragment of IgGD2B mAb (scFvD2B) labelled with 123I, present high tumor affinity, with shorter circulatory half-life. The aim of this work was to develop a new radiopharmaceutical based on the scFvD2B radiolabel with Lu-177 to treat metastases of PCa.