Health Canada approves first human trial for experimental cancer drug
Sep 26, 2007

EDMONTON - Health Canada has approved the first human trial of an experimental cancer drug called dichloroacetate, or DCA, in people with an advanced form of an aggressive brain cancer.
The molecule has drawn international attention after the University of Alberta's Dr. Evangelos Michelakis published promising results in January showing it significantly shrunk tumours in rats. This new trial will give doctors a clue as to whether the research's impressive results will make the jump into human subjects.
"Typically from the time you report results in animals to the point that you test in a human being, takes about three years, even with the support of the pharmaceutical industry," Michelakis said Wednesday. "For us to have completed it in eight months is remarkable."
Researchers hope to try the drug on up to 50 people with glioblastomas over the next 18 months. Michelakis said they are recruiting from the Edmonton area to start, but aren't ruling out allowing people from other provinces to take part, as long as the funding can be found. The first subjects could begin within a few weeks.
The research is being funded entirely by grants and donations. DCA, which has been used to treat certain rare metabolic disorders in humans, is cheap and can't be patented, which Michelakis says is why pharmaceutical companies aren't interested in helping develop it as a cancer therapy.
The team has raised $800,000, enough to fund the first trial, and have a goal of $1.5 million.
There is a lot of interest in the therapy. Only a day after news of the approval was made public, researchers received calls from at least 100 people volunteering for the trial.
Many of the callers had all types of cancer, but researchers say they only have approval to test the drug on people with the specific brain cancer glioblastoma.
Michelakis acknowledged cancer therapies that are promising in animals often fizzle out when applied to humans. But he said the frenzy around DCA shows people are willing to come together to test out promising research regardless of whether it will be profitable.
"This by itself is as important as if the drug were to be working, because a lot of promising drugs never make it to clinical trials because there's no industry to support it," he said.
"With the help of people contributing, or fundraising, and the commitment of academic institutions and not-for-profit institutions, this is possible, and that has huge implications for the future of health care."
That interest has also sparked some negative reactions. The Canadian Cancer Society has warned people not to use the drug until it has been fully tested in humans, after reports some desperate cancer patients were trying to self-medicate with the chemical.
"In the absence of any human data to suggest the use of DCA is either safe or effective, it's potentially life threatening for people to be using DCA," Heather Logan, the society's director of cancer control policy, said Wednesday.
"(The trial) is an important step."
The appeal of DCA lies in its ability to target cancer cells while leaving other cells intact, eliminating severe side-effects of conventional cancer therapies such as chemotherapy and radiation.
DCA cuts tumours off from glucose, said Kenn Petruck, the head of neurosciences with Capital Health and a co-investigator on the clinical trial. "Unlike normal cells, tumours are addicted to glucose as their foodstuff," he said.
Without this food, they turn to another pathway, which triggers the cells to die off.
While it will take nearly six months to see whether the therapy lengthens the life of those taking it, the researchers say it'll only take six weeks to determine whether it's having the desired effect. They'll monitor the intake of glucose by the tumours during the treatments and hope to see it slowly decreasing, leading to a tumour that either stops growing or actually shrinks.
The trial is known as a Phase 2 trial under Health Canada guidelines. That means it's being tested on whether it is effective on a certain population. Phase 1 trials are usually done first, but the researchers say enough work has been done on the molecule in humans that they can proceed without it.
They're only allowed to run a Phase 2 trial for the very aggressive and specific type of cancer, however. Known as "the terminator," the cancer has an average survival rate of one year with conventional therapy, said Petruck. They'll target the people with the more severe types of the cancer, and will accept people with newly diagnosed tumours and people who have exhausted traditional therapy.
A Phase 1 trial will be run on other types of cancers in the near future, pending approval from Health Canada.

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