Targeted Radionuclide Therapy (TRT) can provide selective cancer treatment when other therapy options (chemotherapy and surgery) became inefficient (e.g. multiple metastases). TRT based on Meitner-Auger electron emitters (MAE) provide the most selective treatment option at the cellular level thanks to the low energy of MAE (eV) and high linear energy transfer (LET) which allows when using suitable delivery system damage only targeting cell with no harm to neighboring cells [Radchenko et al.2020].

 Importantly, many promising radionuclides for Targeted Meitner Auger Therapy (TMAT) can be produced with small medical cyclotrons which makes them widely available to many research centers and clinics globally [Filosofov et al 2021].

Recently many pre-clinical and several clinical studies were performed with commercially available candidates (e.g. 111In, 67Ga, or 125I) which are not necessarily the best suitable for TMAT.

My research program actively working on establishing the production and radiochemical separation of several promising candidates, including but not limited to 119Sb, 197m/gHg,103Pd, 135La, 155Tb and 165Er. All those radionuclides can be produced with TRIUMF’s TR-13 (13 MeV) cyclotron from solid and liquid targets. Importantly, after production radionuclides need to be isolated from the target material to allow further chelation and incorporation with suitable delivery vectors (e.g. peptides, antibodies or nanoparticles). Therefore, efficient radiochemical separation needs to be developed. Typically, radiochemical purification based on ion exchange chromatography and/or solid-phase extraction provides the most convenient separation and allowing have the final radionuclide with the purity and media suitable for further radiolabeling and automation of the separation process.

Developing and testing of radiopharmaceuticals for TMAT

Picture Credits to Gokce Engudar

Concept of Targeted Radionuclide Therapy (from [Radchenko et al.2020].