Potential brain-cancer drug shows promise
The generic drug dichloroacetate, or DCA, warrants more research as a potential therapy for a deadly form of brain cancer, according to a small Canadian study with unconventional funding.
The study published in Wednesday's online issue of the journal Science Translational Medicine showed tumours responded to DCA by changing their metabolism. The drug worked against tumour tissues from five patients with terminal brain cancer as predicted by test-tube experiments first reported on in 2007.
"We can conclude that DCA is possibly safe and maybe clinically effective in some patients," said one of the study's lead authors, Dr. Evangelos Michelakis of the University of Alberta in Edmonton.
"Due to the small size of this study we can't make more speculations. However, these early findings are enough to create enough enthusiasm and inspiration and momentum to go to the next step, which involves multi-centre trials."
The generic drug is usually used to treat a rare enzyme disorder in children, but there is no patent and therefore any profit potential for a pharmaceutical company.
Terry Babiy, owner of a radio station in Peace River, Alta., had lost his sister-in-law to cancer and was infuriated by the lack of funding for Michelakis' research. He mobilized the town, which raised $365,000.
"The community responded, and they responded big time, people dropping off money from five dollars, to fifty dollars to hundreds of dollars," Babiy said.
The university contributed resources and equipment and federal funding agencies, also helped the researchers do the first clinical trial in humans.
"We challenged the dogma that without industry you can't actually test drugs on human beings," Michelakis said.
New angle of attack
In four of the glioblastoma patients, researchers saw no further brain cancer growth 15 months after initial treatment. Follow-up studies on cells taken from these patients showed that DCA killed cancer cells.
Nerve damage can occur at higher doses of DCA, but the study's authors suggest that at the dose used in the study, the drug might be able to clamp down on tumor growth without serious side-effects.
DCA has not been approved by regulators as a treatment for cancer — a step that requires evidence from larger clinical trials.
Because DCA has a unique way of killing cancer cells, the new findings represent progress in a new area of cancer research that may stunt growth of tumours without harming healthy cells.
"It warrants further examination, but this is not the holy grail right now," said Dr. Abhijit Guha, a professor of surgery at the University of Toronto.
"I think it forms another angle of attack."
If researchers can understand how the tumour adapts its glucose metabolism to reap survival advantages, then DCA could be used in combination with other therapies to extend the lives of glioblastoma patients, Guha said. Currently, their average survival is 14 to 16 months with standard treatments, he noted.
In the meantime, Michelakis cautioned people against trying to buy the drug online. On Tuesday, Hazim Gaber, 21, of Edmonton pleaded guilty to five counts of wire fraud in the U.S. for selling corn starch over the internet and calling it DCA.