Coronavirus: malaria drug linked to corona deaths but trial goes on

A study linking an antimalarial drug with higher death rates from COVID-19 raises ‘warning flags’.

‘You can imagine that in using these various drugs, if it’s left up to the individual clinician about whether to prescribe the drug or not, there’s all kinds of potential ­biases’: Associate Professor Steven Tong. Picture: Supplied

Scientists leading a clinical trial into coronavirus treatments have conceded a study linking the antimalarial drug hydroxychloroquine with higher death rates from COVID-19 raises “warning flags” but have vowed to press cautiously ahead with administering the drug to Australian patients.

Hydroxychloroquine will be given to Australian patients who are hospitalised with COVID-19 during a major clinical trial involving more than 70 hospitals across the country. The trial will also test the efficacy of the HIV drug ­lopinavir, either on its own or in combination with hydroxy­chloroquine.

The drug, currently taken by hundreds of thousands of Australians as a medication to treat ­arthritis and prevent malaria, has been touted as a miracle treatment for COVID-19 by US President Donald Trump, despite a lack of evidence of whether the treatment is effective in treating the disease.

Former Australian politician Clive Palmer has purchased 33 million doses of the drug and donate­d them to the National Medical Stockpile.

A US study of 368 patients with coronavirus found that those who were administered hydroxy­chloroquine were no less likely to require ventilation and had a ­higher death rate from COVID-19 than patients who took no medication.

The study, which has not yet been peer reviewed, examined the clinical outcomes of 368 patients treated at US Veterans Health ­Administration medical centres.

It found 97 patients who took ­hydroxychloroquine had a 27.8 per cent death rate from COVID-19, whereas 158 patients who did not take the drug had an 11.4 per cent death rate.

The leaders of the Australian clinical trial, known as the ASCOT trial, say they are considering the study but believe its findings are unreliable because the US patients who were administered hydroxychloroquine were likely to have been more severely ill than those who were not and therefore more likely to die in any event.

“We’d be silly not to be concerned, and we keep an eye on the literature, which is coming out thick and fast,” said the ASCOT trial’s lead researcher, Royal Melbourne Hospital infectious diseases­ clinician Steven Tong.

“But you can imagine that in using these various drugs, if it’s left up to the individual clinician about whether to prescribe the drug or not, there’s all kinds of potential ­biases. And so the two populations of patients who get the drug versus those who don’t are not very comparab­le.”

Professor Tong, who is also the co-lead of clinical research at the Doherty Institute, said there were multiple safeguards built in to the ASCOT trial, and if there was any evidence of serious harm from the drug it would be discontinued from the study.

“I think the US study does raise warning flags, but the reason why you do trials is you set up an ethical and safe framework to test these drugs. If there is really convincing evidence, which I would say this US study is not, that one of the drugs in our trial was causing harm, we would stop that.”

The ASCOT trial will recruit up to 2000 coronavirus patients in Australia, New Zealand and Singapore, among other countries. Patients who are sick enough to require hospitalisation but not ­intensive care will be asked to participa­te.

The trial aims to assess whether hydroxychloroquine or lopinavir prevent patients ­becoming sick enough to be admitted to intensive care.

ASCOT trial principle investig­ator Josh Davis, from the Hunter Medical Research Institute, said the US study should be interpreted with caution. “The study was a preprint, it hasn’t been peer reviewed and I think people really should be cautious about interpreting it,” Professor Davis said.

“I think nothing that’s been published so far should convince anybody one way or the other.”