Researchers in Hong Kong have found that patients suffering milder illness caused by the new coronavirus recover more quickly if they are treated with a three-drug antiviral cocktail soon after symptoms appear.
Authors of the study, published in the Lancet on Friday, described the findings as “early but important”.
They called for larger-scale research on critically-ill patients to ascertain if the drug combo could be a viable treatment for them too.
“Our trial demonstrates that early treatment of mild to moderate Covid-19 with a triple combination of antiviral drugs may rapidly suppress the amount of virus in a patient’s body,” said Kwok-Yung Yuen, professor at the University of Hong Kong, who led the research.
He said the treatment, which appeared safe in patients, was shown to “relieve symptoms, and reduce the risk to health-care workers by reducing the duration and quantity of viral shedding (when the virus is detectable and potentially transmissible)”.
Scientists are racing to identify effective medicines to use against the new coronavirus, but there is currently no treatment, cure or vaccine.
The study tracked the virus in 127 adults admitted to six hospitals in Hong Kong after they tested positive.
Of those participating, 86 patients were given a two-week course of three medicines: interferon beta-1b, a drug used to treat multiple sclerosis; HIV drugs lopinavir-ritonavir; and ribavirin, used to treat hepatitis.
A randomly-assigned control group of 41 people was just given the lopinavir-ritonavir combination.
Treatment began on average five days after symptoms started and all patients otherwise received standard care, including oxygen therapy.
Researchers then measured how long it took for a swab test for the virus to turn out negative.
They found that those taking all three medicines were able to clear the coronavirus in seven days on average (between five and 11 days) — “significantly” shorter than the 12-day average for the control group.
Those on the three-drug regimen also saw a complete alleviation of their symptoms in an average of four days, compared to eight for the control group.
The study was carried out between February 10 and March 20 in Hong Kong, where everyone who tests positive for Covid-19 is admitted to hospital.
The authors conceded several limitations with the trial, including that it was “open label” — people knew which drugs they were taking and there was no placebo.
Also, patients admitted more than seven days after the onset of symptoms were not given interferon because of concerns that it could cause inflammation.
Of these, 34 were given the combination of lopinavir-ritonavir and ribavirin, while 17 were in the control group.
Both of these groups took equally long to clear the virus which, the authors suggested, meant that interferon was key to the shorter illness for the patients treated from the first week of symptoms.
“Future clinical study of a double antiviral therapy with interferon beta-1b as a backbone is warranted,” the study said.
Reacting to the study, Stephen Evans, Professor of Pharmacoepidemiology at the London School of Hygiene and Tropical Medicine, said it “justifies the consideration of adding interferon beta to the list of genuinely, evidence-based, promising treatments to be tested in further randomised trials.
“It has been clear from long experience that HIV is best treated with combinations of different drugs and this could also be the case with Covid-19,” he added.