The malaria drug, hydroxychloroquine, was ineffective in preventing infection in people exposed to coronavirus, a clinical trial released on Wednesday has reportedly shown.
The study was conducted on 821 people by researchers from the University of Minnesota and Canada.
The study is the first large controlled clinical trial of hydroxychloroquine conducted after the malaria drug was promoted by U.S. President Donald Trump as a treatment for COVID-19.
In March, Mr Trump repeatedly promoted the drug saying he had recently taken it himself.
He said hydroxychloroquine, used in combination with the antibiotic azithromycin, had “a real chance to be one of the biggest game-changers in the history of medicine,” with little evidence to back up that claim.
He later said he took the drugs as a preventive measure after two people who worked at the White House were diagnosed with COVID-19, the illness caused by the coronavirus.
The need to research the efficacy of the drug became necessary as some studies conducted in China and France when the virus first broke out had seen varying results.
Hydroxychloroquine has anti-inflammatory and antiviral properties and inhibited the virus in laboratory experiments.
But human trials are needed to definitively demonstrate whether the drug’s benefits if any, outweigh the risks when compared with a placebo.
The new study published in the New England Journal of Medicine found no serious side effects or heart problems from the use of hydroxychloroquine.
The study conducted in the U.S. and Canada was also the first to test whether the drug could prevent illness in people who have been exposed to the coronavirus.
Ever since Mr Trump’s pronouncement, there have been a lot of debates raised on if the widely available malaria drug would be effective in the fight against the COVID-19.
The debate on the efficacy of the drug also took place in Nigeria when a politician and founder of DAAR Communications, Raymond Dokpesi, said he used chloroquine as part of his treatment for COVID -19.
Proponents of the drug as a COVID-19 treatment argue it may need to be administered at an earlier stage in the disease to be effective. Others had suggested that it needs to be used in combination with the mineral zinc, which can help boost the immune system
In the study, the patients were picked at random to receive either an experimental treatment or a placebo considered the most reliable way to measure the safety and effectiveness of a drug.
The participants were healthcare workers and people who had been exposed at home to ill spouses, partners or parents.
The lead author of the study, David R. Boulware, from the University of Minnesota, told The New York Times that the take-home message for the general public is that ”if you’re exposed to someone with COVID-19, hydroxychloroquine is not an effective post-exposure preventive therapy.”
The study found 11.8 per cent of subjects given hydroxychloroquine developed symptoms compatible with COVID-19, compared with 14.3 per cent who got a placebo.
The difference was not statistically significant, meaning the drug was no better than the placebo.
More than 20 per cent of the trial subjects also took zinc, which had no significant effect.
The U.S. Food and Drug Administration cautioned in late April against the use of hydroxychloroquine in patients with heart disease due to an increased risk of dangerous cardiac rhythm problems.
Boulware said his trial had fewer participants than initially planned because of difficulty enrolling new subjects after the FDA’s warning.
“Our data is pretty clear that for post-exposure, this does not really work,” he said.
“I think both sides – one side who is saying ‘this is a dangerous drug’ and the other side that says ‘this works’ – neither is correct,” said Boulware.
Several trials of the drug have been stopped over concerns about its safety.
However, the World Health Organisation has also resumed its trial of hydroxychloroquine after the research was temporarily halted over safety concerns.
On May 25, WHO announced it had temporarily suspended its trial of the drug over safety concerns.
The announcement came days after a study published in the medical journal, The Lancet found that hospitalised COVID-19 patients treated with hydroxychloroquine had a higher risk of death than those who didn’t take it. That study is now being reexamined.
The Data Safety Monitoring Board decided there was no reason to discontinue the international trial after reviewing available data on the drug, WHO Director-General, Tedros Ghebreyesus, said during a press conference Wednesday at the agency’s Geneva headquarters.
Meanwhile, some European governments have banned hydroxychloroquine for COVID-19 patients, and U.S. hospitals have significantly cut back on its use.
Mr Ghebreyesus said the executive group received the new recommendation and endorsed the continuation of all arms of solidarity trial including hydroxychloroquine.
He said there’s no evidence that any drug actually reduces the mortality in patients who have COVID-19.
Mr Ghebreyesus also said the safety board will continue to closely monitor the safety of all therapeutics being tested in its trials, which involve more than 3,500 patients across 35 countries.