Accelerator-Based Production of Scandium Radioisotopes for Applications in Prostate Cancer: Toward Building a Pipeline for Rapid Development of Novel Theranostics

In the field of nuclear medicine, the β⁺ -emitting ⁴³Sc and β⁻ -emitting ⁴⁷Sc are promising candidates in cancer diagnosis and targeted radionuclide therapy (TRT) due to their favorable decay schema and shared pharmacokinetics as a true theranostic pair. Additionally, scandium is a group-3 transition metal (like ¹⁷⁷Lu) and exhibits affinity for DOTA-based chelators, which have been studied in depth, making the barrier to implementation lower for ^43/47Sc than for other proposed true theranostics. Before ^43/47Sc can see widespread pre-clinical evaluation, however, an accessible production methodology must be established and each isotope’s radiolabeling and animal imaging capabilities studied with a widely utilized tracer. As such, a simple means of converting an 18 MeV biomedical cyclotron to support solid targets and produce ⁴³Sc via the ⁴²Ca(d,n)⁴³Sc reaction has been devised, exhibiting reasonable yields. The ^NatTi(γ,p)⁴⁷Sc reaction is also investigated along with the successful implementation of chemical separation and purification methods for ^43/47Sc. The conjugation of ^43/47Sc with PSMA-617 at specific activities of up to 8.94 MBq/nmol and the subsequent imaging of LNCaP-ENZaR tumor xenografts in mouse models with both ^43/47Sc-PSMA-617 are also presented.