Increasing the Arsenal of Radioisotopes in the Fight Against Cancer

A new supply of a critical radioisotope advances personalized medicine.

The Science

Researchers have deployed a newly developed method to produce large quantities of copper-67. This material is a promising medical radioisotope–isotopes with applications in health care. The increased supply of copper-67 will enable clinical studies for new drug discovery in the fight against cancer. Copper-67 is important for its “theranostic” properties. These properties mean it has emissions suitable for both diagnostic imaging and targeted cancer therapy.

Image credit: Pixabay (Free Pixabay license)

The Impact

Pharmaceuticals that incorporate radioactivity can greatly advance personalized medicine. This approach to health care tailors treatment to a patient’s individual response. The combination of diagnostic and therapeutic agents can be particularly effective. Doctors use diagnostic agents to visualize cancer tumors and determine the best treatment. They then use therapeutic agents to treat the disease. Copper-67 is a “theranostic” radioisotope: it can visualize tumors and treat the disease in a single radioisotope. The use of a single agent means patients need fewer injections and visits to the hospital, reducing health care costs. In addition, doctors can pair copper-67 with its diagnostic analogue copper-64 to create higher-resolution images for image-guided therapy.

The DOE Isotope Program supports the production of radioisotopes in short supply for research and applications. They can be used in radiopharmaceuticals (pictured here) that are specifically engineered to seek out and/or destroy cancer. Image credit: Argonne National Laboratory/Ellen Weiss.

Summary

Researchers have increased the availability of copper-67 by increasing production quantities per batch by a factor of 10 through the development of novel targetry and hot cell operations. This advance means that the Department of Energy Isotope Program can now produce clinically relevant quantities of copper-67 in very high purity and supply it through the National Isotope Development Center. The copper-67 is produced using a high-power electron beam and special zinc targets; a portion of the zinc target is transmuted into copper-67. The first step in isolating pure copper-67 from zinc is removing the bulk zinc by boiling it away from the copper-67. With this process, the zinc can be collected, saved, and recycled for future copper-67 production, further minimizing costs. Once the bulk zinc is removed, the copper-67 residue is dissolved and purified by column chromatography, much the same way that drinking water is purified using common water filters. This process provides large quantities of very pure copper-67 that has been shown to be well-suited for use in radiopharmaceutical agents.

Funding

This work is supported by Argonne National Laboratory and the U.S. Department of Energy (DOE) Isotope Program managed by DOE’s Office of Science.

Publications

Chen, J. et al., “Precise absolute γ-ray and β—-decay branching intensities in the decay of 67Cu.” Phys. Rev. C. 2015, 92(4), 0443300 [DOI: 10.1103/PhysRevC.92.044330].

Ehst, J. and Willit, L., U.S. Patent 20130083882, “Methods for producing Cu-67 radioisotope with use of a ceramic capsule for medical applications” (2012)

D. Ehst, D.L. Bowers, U.S. Patent 20100028234, “Methods for making and processing metal targets for producing Cu-67 radioisotope for medical applications” (2010)

Related Links

National Isotope Development Center New Release: Routine Production and Availability of High Specific Activity Copper-67

Source: U.S. Department of Energy