First testing in human subjects with radioactive cisplatin CISSPECT scheduled to start soon
 
PETTEN – NRG has developed a radioactive platinum isotope that may help to better predict the efficacy of frequently applied chemotherapy with cisplatin in cancer patients or predict harm caused by this type of treatment. Clinical testing with human subjects is scheduled to start soon in order to investigate the feasibility and effect of this CISSPECT.
 
Cisplatin, a compound made of platinum, chlorine and ammonia, has been used in cisplatin chemotherapy since the 1970s. Because it stops cell division, it works very well with fast-
growing tumours and is used, among other things, in chemo treatments for head and neck cancer, lung cancer and testicular cancer. However, cisplatin therapy is not equally effective for every type of cancer. Some 95% of testicular cancer patients are cured with chemotherapy using cisplatin, but far fewer lung cancer patients benefit from this treatment.
It can also have serious side effects, such as hair loss, nausea, hypersensitivity of the hands and feet, hearing impairment and even kidney failure. Some patients treated with this chemotherapy eventually have to undergo regular kidney dialysis.
 
It is therefore important to know which patients benefit from treatment with cisplatin and who do not, and which patients are expected to experience side effects. In order to determine the answers to these questions, based on clinical research, NRG’s Karlijn Codée-van der Schilden designed an automatic process to replace the natural platinum in cisplatin with the radioactive platinum isotope Pt-195m. A part of the cisplatin becomes radioactive due to this process. This radioactive variant of cisplatin is called CISSPECT and has exactly the same effect during chemotherapy as regular cisplatin. A standard scan can identify the place and concentration of the CISSPECT in the patient, for example in tumour tissue and in critical organs.
“This way radioactive cisplatin could be a predictor, allowing you to identify patients who would not benefit from chemotherapy with cisplatin. If a lot of it does enter the tumours, you can then use chemotherapy with regular cisplatin for those patients. You would also be able to see whether it is absorbed by the healthy organs on a large scale and then weigh the chance of kidney failure against a treatment, for example. We are not yet sure whether CISSPECT works, which is why research with human subjects is now being planned,” explains Codée-van der Schilden.
 
CISSPECT can also be used for research on the effect of cisplatin in the body. Codée-van der Schilden: “Although it has already been used for more than 30 years in chemotherapy and combination therapies, we still don’t know exactly where in the body it ends up and what it actually does. Radioactive cisplatin is suitable for these kinds of research goals. Or as a tracer for determining where future medications end up in nanoparticles or antibodies, for example, or how the cisplatin spreads in the patient if it is locally administered in or near tumour tissue.”
 
NRG is working together with various partners who will soon start pilot studies with human subjects during which small quantities of CISSPECT will be administered in safe way. NRG recently automated the process and developed a production facility with which the radioactive cisplatin can be produced twice as fast as before and in a controlled manner. This will make further research possible, also in human subjects.