A cheap anti-viral pill could stop Covid-19 patients developing pneumonia, according to new research.
Remdesivir is the only drug proven to help treat the disease, but supplies are running short because of its success.
Now a study in macaque monkeys has found it prevents infection of the lungs – which can lead to death.
The findings published in Nature support early use of the medication to prevent complications in humans.
Corresponding author Dr Emmie de Wit, of the National Institute of Allergy and Infectious Diseases, Montana, said: ‘The results indicate remdesivir treatment of Covid-19 should be initiated as early as possible to achieve the maximum effect.’
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The drug, which costs about a dollar (80p) a dose, was made available on the NHS last month after appearing to shorten recovery time for people with the coronavirus.
Health Secretary Matt Hancock described it as the biggest step forward in treatment since the crisis began.
Remdesivir was developed by California based Gilead Sciences for use against Ebola, the deadly fever that emerged in West Africa in 2014.
Dr de Wit said: ‘Dosing of remdesivir in the rhesus macaques is equivalent to that used in humans.’
In experiments two sets of six monkeys were infected with Covid-19, one of which received remdesivir 12 hours later – close to the peak of virus replication in the lungs.
They were given it every 24 hours for six days. In contrast to the control group, they did not show signs of respiratory disease.
They also suffered less damage to the lungs with viral levels around 100 times lower – after just one dose.
Dr de Wit said: ‘Infectious virus could no longer be detected in the treatment group three days after initial infection – but was still detectable in four out of six control animals.’
She added: ‘Effective therapeutics to treat Covid-19 are urgently needed.
‘Although the rhesus macaque model did not represent the severe disease observed in a proportion of patients, our data support early remdesivir treatment to prevent progression to pneumonia.’
Most patients’ immune system mounts a reponse to the virus and they begin to feel better after a few days.
But in some it goes into overdrive and starts attacking the lungs and other organs. This can lead to pneumonia and breathing difficulties – which can prove fatal.
In the UK the drug is given intravenously to those most likely to benefit due to limited supplies. It is currently undergoing clinical trials around the world.
Early data suggests it can cut recovery time by about four days. But there is no evidence yet it saves lives.
The US government says its supply will run out at the end of the month. The Food and Drug Administration will send out its last shipment during the week of June 29.
Gilead is ramping up production but it’s unclear how much of the drug will be available for patients over the summer.
The medication appears to help stop the replication of viruses like coronavirus and Ebola alike.
It’s not entirely clear how the drug accomplishes this, but it appears to prevent the genetic material of the virus, known as RNA, from being able to copy itself.
