A private clinic in Toronto is
among the first places in the world to prescribe dichloroacetate
(DCA) to cancer patients, ignoring warnings from researchers
and the Canadian Cancer Society that DCA's effectiveness
and safety are not yet proven.
Medicor Cancer Centres' founders
Dr Akbar Khan and his wife Dr Humaira Khan began prescribing
the drug in mid-April.
DCA, which has been used for years
as a treatment for some rare metabolic disorders including
lactic acidosis, was recently shown to shrink human
tumours in a laboratory by inducing apoptosis in Cancer Cells by reactivating disabled mitochondria. Dr Evangelos
Michelakis and colleagues at the Universities of Calgary
and Ottawa reported the discovery on January 17 in Cancer
Cell, setting off a flurry of breathless news reports
and a groundswell of interest among patients on the
internet.
DCA
DISCORD
Many researchers are furious that the Toronto clinic
is offering DCA. Tak Mak, PhD, a University of Toronto
researcher who co-authored a review of Dr Michelakis's
DCA study in Science's STKE journal in April,
says DCA can cause serious neurotoxicity — a problem
that can be exacerbated by chemotherapy.
Dr Khan defends his decision, saying
he's well aware of the potential side effects. "We feel
that with very close monitoring, if there were any problems
we would be able to pick up on them and stop the DCA,"
he says in an interview with NRM. "I'm pretty
confident we're not harming anyone — from what
we know about DCA we are confident we're not causing
harm."
DESPERATE
MEASURES
Soon after the Cancer Cell study appeared, reports
emerged that patients were buying DCA online and self-medicating.
Many have been sharing their experiences at TheDCAsite.com,
a website owned by California biologist Jim Tassano,
who also sells the drug on his sister site, BuyDCA.com.
(NRM first reported on this in "Quacks
pervert U of A doc's discovery," April 15, 2007,
Vol 4, No 7.)
Besides being potentially dangerous
to patients, Dr Michelakis has warned that unregulated
use of DCA could threaten the prospects of carrying
out a clinical trial. The absence of a control group
makes any positive data reported online largely meaningless,
and reports of illness caused by non-pharmaceutical
grade DCA or the drug's sometimes severe adverse effects
could scare off potential clinical trial participants,
he told Nature in March.
"That doesn't concern me," says
Dr Khan of Dr Michelakis's disapproval. "He has to understand
that by prescribing it we are helping the scientific
community and helping patients learn what are the side
effects and the effects of it being used on cancer."
EXPERIMENTAL
CASES
Dr Khan's clinic charges advanced-stage cancer patients
about $150 per week for the medication and bills the
public Ontario Health Insurance Plan (OHIP) for the
patient visits, unless the patient opts to pay for Medicor's
private care package. Dr Khan says he makes no profit
on DCA therapy.
Neither Dr Khan nor his wife are
oncologists. She's a public health epidemiologist who
has worked for several government agencies, and he's
a family physician who claims 13 years of cancer-care
experience, mostly in pain- and symptom-management.
It's all perfectly legal — since it's off-label,
it's fine with Health Canada, and patients are fully
informed of all the risks.
The couple has now treated or are
currently treating a total of 15 patients with DCA.
Four have shown significant improvements, says Dr Khan
— the rest have either died or seen no improvement.
One of those four patients, a 65-year-old
man diagnosed with pleural mesothelioma that has metastasized
to the abdomen and the lymph nodes, has seen a lymph
node tumour shrink from 6.0x4.2cm to 5.5x3.6cm after
four days of high-dose — 45mg/kg per day —
DCA therapy. The patient, however, has already been
put on DCA twice before and both times had to stop treatment
due to side effects. The three other patients —
suffering from bone, lung and ovarian cancer respectively
— have all seen improvements, Dr Khan says.
Dr Khan is now trying to determine
whether a combination of vitamin B1 and alpha-lipoic
acid will counteract DCA's neurotoxicity. In the meantime,
his clinic continues to take new cancer patients interested
in DCA.
"It comes down to patients' rights,"
Dr Humaira Khan told the Edmonton Journal last
month. It's better to have these patients under a physician's
supervision than to leave them to take DCA without any
monitoring, she added.
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