Trial data of the drug’s use, however, has not been made available by China. Scientists have dismissed a widely quoted online report that about 12,000 patients have been completely cured of Covid-19 in China after taking chloroquine.

Paterson said laboratory tests using a combination of the two drugs had indicated that they might provide a “cure” from the virus.

“It’s a potentially effective treatment. Patients would end up with no viable coronavirus in their system at all after the end of therapy,” he said.

The March 18 decision to go ahead with the human tests was only made after the researchers made an extraordinary global appeal for donations to cover the funding cost, estimated at A$750,000 (US$451,415).

There is an urgent push to develop effective Covid-19 treatments because a vaccine for widespread use is not expected to be developed for at least 18 months.