LOS ANGELES, July 31 -- A synthetic version of the venom of a deadly insect is being tried to help patients with glioblastoma multiforme, according to researchers here.
A peptide called chlorotoxin -- found in the venom of the giant yellow Israeli scorpion Leiurus quinquestriatus - has the unusual property of crossing the blood-brain barrier and binding to tumor cells, but not normal cells, according to Adam Mamelak, M.D., a neurosurgeon at Cedars-Sinai Medical Center here.
Preclinical studies suggested that combining the peptide with radioactive iodine(Drug information on iodine) might be a useful way of attacking gliomas, a tumor type whose prognosis has not improved in two decades, Dr. Mamelak and colleagues reported in the August issue of the Journal of Clinical Oncology.
And in a Phase I safety trial, the researchers said, the combination of the synthetic peptide - dubbed TM-601 -- and iodine131 was well-tolerated, with no apparent dose-limiting toxicities. While the study was not designed to evaluate efficacy, the treatment appeared to have an anti-tumor effect, said Dr. Mamelak and colleagues. A Phase II dose-finding study is under way.