Gliomas can be an aggressive type of brain tumor. According to statistics, only 8 percent of patients with glioma survive two years and 3 percent survive five years after diagnosis. Current treatment methods, iincluding surgery and chemotherapy, have not significantly lengthened survival for glioma patients. Now research reports that a synthetic version of the yellow Israeli scorpion venom has been successfully used to improve glioma treatment.
The study, published in the Journal of Clinical Oncology, investigated the safety, distribution, and dose of TM-601 (synthetic scorpion venom) used as a carrier of radioactive iodine-131 (131I) in glioma patients. Since TM-601 can bind to malignant brain tumor cells and not to healthy brain cells, it was used as a carrier to deliver radioactive iodine into tumor cells that remained after surgery to remove gliomas. At the beginning of the study, 18 patients had their gliomas surgically removed. Two weeks after surgery, researchers at Cedars-Sinai Medical Center, in California, injected a low dose of TM-601 with radioactive iodine into the tumor cavity where the glioma was removed.
The researchers found that the treatment was effective and well tolerated. The TM-601-radioactive iodine drug remained localized to the tumor cavity. This suggested that the drug was binding to brain tumor cells and not to healthy brain cells. After 6 months, four of the patients had no evidence of glioma and one patient had partial improvement. After 30 months, two of those patients continued to have no evidence of glioma.
The researchers suggest that the venom drug can be used in conjunction with chemotherapy and are planning additional studies. "A single dose of 10 mCi 131I-TM-601 was well tolerated for 0.25 to 1.0 mg TM-601 and may have an antitumoral effect," the study authors conclude. "Dosimetry and biodistribution from this first trial suggest that phase II studies of 131I-TM-601 are indicated."
REFERENCES:
1. Mamelak AN et al. Phase I single-dose study of intracavitary-administered iodine-131-TM-601 in adults with recurrent high-grade glioma. J Clin Oncol 2006 Aug 1;24(22):3644-50.
Posted by Elaine Gavalas on August 20, 2006 02:50 PM
