Trump loves it, but Canada has questions
Clinical trials continue for hydroxychloroquine under careful monitoring
OTTAWA— Canadian doctors and researchers involved in clinical trials into hydroxychloroquine worry the drug’s got a bad rap before its risks and benefits in COVID-19 patients have been properly scientifically examined.
Health Canada says it is allowing approved Canadian trials of hydroxychloroquine to continue for now.
Four days ago, the World Health Organization suspended its global trial into the drug as a precaution to review the safety data, followed by other European countries including the United Kingdom, after early evidence emerged that the drug touted by U.S. President Donald Trump can cause heart arrhythmia in people sick with COVID-19.
There are at least10 controlled clinical trials underway in Canada.
But the Star has learned the federal regulator has asked all Canadian researchers to provide the government with early independent safety reports — safety data that is normally reviewed at regular intervals when clinical trials are at the stage of widespread, randomized testing — and hasn’t ruled out a suspension of trials in this country.
“Health Canada will continue to closely monitor the safety and effectiveness of hydroxychloroquine, and other drugs used in the treatment of COVID-19, and will take appropriate and timely action if, and when, any new health risks are identified, including informing Canadians,” said Health Canada spokesperson Andre Gagnon in a statement the Star. France went further on Wednesday and banned the drug for coronavirus treatments, after allowing a twomonth experimental period for hospital use of it.
Hydroxychloroquine is a drug that has both anti-inflammatory and antiviral properties. It has been used to treat autoimmune inflammatory diseases like lupus and rheumatoid arthritis. It’s also been used to treat malaria, a parasitic disease.
It was never fully studied as a treatment for coronavirus disease in the 2003 SARS outbreak, but researchers desperate to find drugs to treat COVID-19 have now turned to study its potential to aid in the latest global pandemic.
Canada’s chief public health officer, Dr. Theresa Tam, said the drug should not be taken outside of a supervised clinical trial, under the care of doctors.
Although no Canadian physicians or researchers sat on the executive group of the WHO that decided to suspend the global Solidarity trial, the Canadian arm of the study has also temporarily suspended enrolment of new patients in the trial until they receive the results of their own internal data safety review, said Health Canada.
But Canadian investigators involved with the Solidarity trial and several other clinical trials here hope these studies — randomized, controlled trials with independent oversight — now underway will be allowed to continue.
Dr. Michael Silverman, chief of infectious diseases at the London Health Sciences Centre and St. Joseph’s Hospital, is an investigator in the Canadian arm of the Solidarity trial, along with two other hydroxychloroquine trials at the London Health Sciences Centre and St.
Joseph’s Hospital in London. He says doctors worry the debate has become politicized.
“There is a lot of concern, because it’s become so politicized in the United States that some people have really wanted to promote it because they’re supporting one party and other people wanted to tear it down because they wanted the other party to look foolish. And that’s not the way to decide whether a drug is good or not,” he said in an interview with the Star Thursday.
“That’s not the way we normally do science. I just want to know the answer, does it work or does it not work, because that would really help the public.”
Silverman is not persuaded by the two biggest studies published to date.
A study in the British medical journal the Lancet and another in the New England Journal of Medicine suggested the drug carries an increased risk of cardiac arrhythmia. Their authors said the evidence needed to be tested in proper randomized controlled studies.
Silverman said those were
“observational studies,” which have statistical biases built in.
The people who got the drug were hospitalized, sicker to begin with, and were more likely to experience more significant side-effects, he said.
But it is important to determine whether there is still a mild benefit with use of hydroxychloroquine in a different population, he said.
“It could be that when used as prevention or very early treatment, it has benefit that is not seen when people are further along and sicker.”
Silverman says he is not “an advocate of the drug, I am an investigator of the drug.”
“It could be that the drug is not helpful and has side effects. It is possible that that’s all there is to it,” he said. “It is also possible that this drug has a mild benefit we’re not aware of because the studies were designed in a way we wouldn’t see a mild benefit … that may overwhelm the risks.”
“And, particularly when you’re talking about the elderly in nursing homes, any benefit would be huge because the death rate is so high.”
“I just want to know the answer, does it work or does it not work, because that would really help the public.”
DR. MICHAEL SILVERMAN CHIEF OF INFECTIOUS DISEASES, LONDON HEALTH SCIENCES CENTRE