Since the discovery of radioactive iodine and later the FDA approval of Radium-223 dichloride as the first clinically approved alpha emitter for treating prostate bone metastases, interest in developing new alpha-therapies for various solid tumors has significantly increased. Perspective Therapeutics is leading the way in advancing these innovative therapies.
Perspective Therapeutics chose Pb-212 as a therapeutic platform for its potent alpha-emitting properties and short half-life. Pb-212’s half-life of 10.6 hours is ideal for therapeutic applications, providing enough time for the radiopharmaceutical to reach and bind to tumor cells while reducing prolonged radiation exposure to the patient. In comparison with other approved radiopharmaceutical isotopes, Pb-212 is differentiated with several advantages.
Harnessing the Power of Alpha-Particles
In contrast to beta-radiation, alpha-particles deliver significantly higher energy at shorter range very specifically to tumor cells, causing complex double-stranded DNA breaks and killing the cancer cells without the emergence of drug resistance. We therefore believe that alpha-particles are more cytotoxic to cancer cells with the potential to spare healthy tissue due to their short range when compared to beta-particle therapy.
Release of an alpha-particle from an atom
Advantages of Alpha-Particles over Beta-Particles
- Higher atomic mass emitted with energies in the range of 4 to 9 MeV
- Complex, lethal double-strand DNA breaks
- Cell death assured – NO resistance due to DNA damage
Alpha-particles creating double stranded breaks in DNA
Tumor-Specific Deposition
- Short particle range limited to 2-3 cell radii (vs beta particles up to 200 cells)
Radiopharmaceutical on tumor cell surface
Anti-Tumor Immune Response
- There is evidence that alpha radiation triggers an anti-tumor-immune response either alone or in combination with immunotherapies
T-cell mediated tumor cell killing and the vaccination effect