Paxlovid – an antiviral made by Pfizer – is now being looked at as a possible long Covid treatment.
The pharma giant’s flagship Covid drug gained emergency approval in the US last December to treat high-risk patients – slashing their risk of death by 90 per cent.
It is currently the only medication you can take at home to treat Covid and has been given to millions of vulnerable Americans with underlying health conditions.
Now, researchers at Stanford are about to launch the first clinical trial of the drug to see it may also provide relief to people who are still ill months and years after clearing the virus.
Prior research has indicated that people given the drug are a quarter less likely to suffer long Covid – which most commonly causes intense tiredness, brain fog and muscle weakness.
As of yet, there are no proven treatments for long Covid, and no one knows what causes the ongoing symptoms.
A popular theory is that there may be bits of leftover virus wreaking havoc in the body. A recent study suggested people with long Covid suffer physical alterations to their brain months after clearing the initial infection.
More than 15million Americans are officially estimated to have long Covid to varying degrees.
Trial participants will take the antiviral drug for ten days longer than people usually take it for, to see if it needs longer to work
The new study hopes to sign up 200 adults who have been negative for Covid for three months yet still suffer symptoms.
Half the participants will receive Paxlovid and half will take a placebo.
To treat an infection, Paxlovid is given as six pills a day for five days, but participants in the new study will take the drug for 15 days to test the theory that the drug needs more time to have its full effect.
Results of the trial are expected next year.
The first participant in the trial was 67-year-old Bill Fimbres from California, who has been suffering with long Covid symptoms for a year-and-a-half, including a loss of smell and taste, debilitating fatigue and brain fog.
He said: ‘It’s like you have somebody else’s brain.’
Mr Fimbres will take his first dose of either the drug or placebo on Monday.
He told NBC News: ‘If I could get rid of just one of my symptoms, that would be great. I’m just going on hope.’
Evidence indicating Paxlovid might stunt long-term symptoms already exists.
A study by the Department of Veterans Affairs this month suggested those who received the drug immediately after their Covid diagnosis were 26 per cent less likely than those who did not take the antiviral to have lasting symptoms three months on.
However, the participants were all aged 60 or above with additional health issues, meaning the findings may not be applicable to everyone.
Long Covid has puzzled scientists and physicians since it first popped on their radar in 2020.
Its causes have not been figured out, but experts believe it could be tied to the body’s immune response to the virus.
There have also been previously known cases of people suffering long-term symptoms after suffering more common viruses like the flu.
The CDC estimates that around 7.5 per cent of American adults are suffering from long Covid symptoms.
Sufferers are generally under the age of 50, and are more likely to be women. Reports of long Covid are most common in southern states like Kentucky and Alabama.