ANU researchers have discovered a low-cost, widely available drug that could fight COVID-19. Heparin limits lung damage when inhaled by COVID-19 patients, according to world-first findings from the Australian National University.

Professor Frank van Haren, the lead researcher, said the drug could be “a promising treatment” and “a possible preventative against the virus”.

Because the drug has antiviral properties and calms the immune system down, the researchers say it could be used at different stages of treatment.

When inhaled, heparin also shows promise as a preventative, and could be used to boost vaccination efforts.

Heparin, normally administered via injection, is a blood thinner used to treat and prevent blood clots across the world.

“This drug is already available in hospitals all over the world, and it is a very inexpensive drug,” Professor van Haren said. “If it is as effective as our early results suggest, it could have a major impact in our fight against COVID.”

The researchers are tracking hospital patients infected with SARS-CoV-2 in 13 countries who were given doses of inhaled heparin.

Breathing and oxygen levels improved in 70 per cent of the patients after they inhaled a course of heparin, and their symptoms improved, according to the World Health Organization (WHO) COVID symptoms scale.

“There is still an urgent need for an effective treatment of COVID-19, and the early results of our trials show inhaled heparin is safe and effective,” Professor van Haren said.

Co-author Professor Clive Page, from King’s College London, explained: “Inhaled heparin has antiviral properties which work by binding to the spike proteins the coronavirus uses to enter the cells of the body.

“Inhaled heparin effectively stops the virus infecting cells in the lungs, and could also stop people from getting the virus from others.

“It also works as an anti-inflammatory drug – the medicine has the ability to calm everything down when the body is mounting an exaggerated response to the virus. We already know heparin can reduce lung damage caused by this inflammation and the immune response overdrive that we see in other lung diseases, which could benefit patients hospitalised with COVID-19.

“It’s also a blood thinner. When COVID-19 patients get very sick, they develop blood clots in the lungs, and these can be lethal. Heparin stops these clots from forming. There is no other drug that has these three different effects – anti-viral, anti-inflammatory and anti-coagulant.”

“Most COVID experts agree that vaccination alone is not going to stop the pandemic,” Professor van Haren said. “This could really assist in poorer countries where vaccination is challenging. We think it could help front line workers who could use it as a preventative measure.

“Inhaled heparin is a promising new possibility to provide a low-cost, safe, and effective treatment for COVID-19 that is available and affordable to low and middle-income countries around the globe.”

Professor van Haren said the team was collecting more evidence that inhaled heparin treats and prevents COVID-19.

“Once we have this evidence, heparin via inhalation could be an option to treat COVID-19 patients, everywhere, within months,” he said.

The findings from the first 98 patients in the studies are published in a new paper in the British Journal of Clinical Pharmacology.