Health physicists are trying to devise safe procedures for a promising experimental brain-cancer therapy which uses a radioactive version of a protein found in scorpion venom.
The purpose of this work is not science fiction, but rather to help to develop a promising new therapy for brain cancer. The venom of the yellow Israeli scorpion preferentially attaches to the cells of a type of essentially incurable brain cancers known as gliomas.
Responding to this urgent problem, scientists at the Transmolecular Corporation in Cambridge, Massachusetts created a radioactive version of this scorpion venom. Called TM-601, it contains an artificial version of the venom protein, attached to a radioactive substance called iodine-131 (I-131). When it enters the bloodstream, the compound attaches to the glioma cells, then the I-131 releases radiation that kills the cell.
This compound has enabled an experimental treatment for high-grade gliomas, found in 17,000 people in the US every year and usually causing death in the first year of diagnosis. Patients would simply be injected with the compound in an outpatient procedure, without needing chemotherapy or traditional radiotherapy. The first, early human trials of the venom therapy showed promising signs for treating the tumor and prolonging survival rates for patients.
“The health physicist has the duty to ensure to ensure that these therapies are conducted both legally and safely,” Jackson says. “Obviously, a key objective is to bring these patients home and to ensure that their loved ones and the environment are properly protected.”
Jackson is encouraged by the safety of this procedure and its potential to help patients with brain gliomas. A recent study of the earlier phase II trials showed that patients receiving up to 40 mCi of weekly dose did not show evidence of any adverse reactions attributable to the radiation. The second-sequence phase II trial at Henry Ford involves 3 patients, with a total of 54 patients across the US currently in investigational trials for the therapy.