Pelindaba, South Africa – Researchers from South Africa and Cuba have joined forces to develop customized cancer therapy treatments, based on the personalized dose each patient needs for effective and safe treatment of tumours. The focus of the research, supported by the IAEA, is cervical and ovarian cancer, which are less prevalent in developed countries, and hence not a priority for these countries.
The research is currently at the animal testing, or preclinical, stage, using, in part, equipment contributed by the IAEA, said Jan Rijn Zeevaart, Head of Radiochemistry at the South African Nuclear Energy Corporation (Necsa).
The Cuban chemotherapy drug nimotuzumab is an antibody that is used in many developing countries to treat various forms of cancer. Researchers from Necsa and Cuba's Center of Isotopes are using Zirconium-89 isotopes, supplied by Australia's Sir Charles Gaidner Hospital, as radiomarkers to study the uptake of the drug in mice. Once this diagnostic imaging technique is developed for people, which could happen in the next few years, it will allow physicians to quantify the dose required for each patient: the higher the uptake for a patient, the lower the dose required. "This will be a major step forward from the current practice, where every patient gets the same dose," Zeevaart said.
While South Africa has a competitive radiopharmaceuticals industry, supplying 18% of the molybdenum-99 used for diagnostic imaging in certain types of cancer, there has historically been a gap in the country's capacities in preclinical imaging, Zeevaart said.
Necsa, in collaboration with North West University and University of Pretoria, has bought a micro-PET device to carry out the experiments on rodents. PET stands for positron emission tomography, a scanning device that is used to observe metabolic processes in the body. It detects pairs of gamma rays emitted indirectly by a positron-emitting radionuclide, the tracer, which is introduced into the body on a biologically active molecule.
The device was installed in April 2015, and the IAEA provided training to scientists on its use. The micro-PET device reveals the relative concentration of the Zr-89-nimotuzumab, but does not provide absolute values, which could then be used to calculate the amount of dose required for treatment. In August 2015, the IAEA provided an automatic gamma counter, which allows scientists to verify the imaging and determine the absolute value of the uptake in each organ. "With both devices available, we are able to move forward with this important research," Zeevaart said.
The contribution from the IAEA ensured that the micro-PET imaging was established in Africa for the first time, said Michel Warnau, Section Head at the IAEA's Technical Cooperation Division for Africa.
The technology is also used to develop imaging for conventional drugs. In collaboration with the Nuclear Medicine department of the Steve Biko Academic Hospital in Pretoria the Gallium-68 markers are developed to be used to identify tuberculosis (TB) bacteria inside and outside the lungs. This can be life-saving for patients with Extreme Drug Resistance (XDR) TB in a country like South Africa, which has relatively high TB rates among the urban poor. Zeevaart and his collaborators are conducting pre-clinical research on perfecting the technique using radiotracers.
