Hailed as a game-changer in the fight against the coronavirus pandemic following the release of trial data, it could lead to a dramatic decrease in hospitalisations and deaths for those who contract Covid-19.
What is it?
The antiviral drug, called molnupiravir, works by stopping the virus from making copies of itself by creating errors in the RNA. This prevents it from spreading throughout the body as a normal Covid-19 infection would.
As it is in capsule form, it is also the first oral medication to fight a Covid-19 infection.
Molnupiravir was developed at Emory University in Atlanta by its drug innovation company, Drug Innovation Ventures at Emory (Drive), which was licensed by Ridgeback Biotherapeutics LP, which partnered with Merck.
Animal studies conducted in 2020 found that molnupiravir could completely suppress viral transmission and prevent and reduce severe lung damage.
A study of mild-to-moderate non-hospitalised adult patients at risk of progressing to severe Covid-19 and hospitalisation due to health problems such as obesity, diabetes, or heart disease, showed that the pill reduced the risk of both needing to be admitted for treatment and of death by 50 per cent.
Of the 762 patients in the study, 7.3 per cent of those who received molnupiravir were hospitalised or died, compared to 14.1 per cent of those who received the placebo. No deaths were recorded in the former group, whereas eight died in the latter.
None of the participants in the trial had been vaccinated.
While the results released by the company have not been peer-reviewed, Merck says it will present them at a future medical meeting.
An independent group of medical experts that monitored the trial recommended stopping it early because the interim results were so strong.
Dr Dean Li, vice president of Merck research, told the Associated Press that the drug had exceeded what he thought it might be able to do in the trial.
“When you see a 50 percent reduction in hospitalization or death, that’s a substantial clinical impact,” he said.
Why is it good?
The reason molnupiravir is hailed as a game-changer is that it will be the first oral antiviral medication that can be taken at home by those who receive a positive Covid-19 test result.
Currently, there are no specific at-home medications to treat coronavirus other than remedies for flu symptoms.
All other FDA-backed treatments against the disease require an IV drip or injection.
Since the beginning of the pandemic, health experts have stressed the need to develop something as convenient as a pill to fight the disease — similar to Tamiflu, the flu medication that shortens sickness and reduces the severity of symptoms.
“The value here is that it’s a pill so you don’t have to deal with the infusion centres and all the factors around that,” said Dr Nicholas Kartsonis, a senior vice president with Merck’s infectious disease unit. “I think it’s a very powerful tool to add to the toolbox.”
Monoclonal antibody drugs from Regeneron Pharmaceuticals and Eli Lilly are difficult to administer and have therefore only seen limited use.
They are also expensive to produce at approximately $2,000 per course of treatment, versus approximately $700 for molnupiravir.
If people can safely treat themselves at home, this would greatly relieve pressure on hospitals that continue to be overloaded with coronavirus patients.
Poorer countries with weaker health systems would benefit enormously if outbreaks could be quickly curbed by at-home treatment.
Is it safe?
Yes. According to data released by Merck and to be reviewed by the FDA, in the trial, the incidence of any adverse event — a change in the condition of the patient for the worse — was comparabl in the molnupiravir and placebo groups (35 per cent and 40 per cent, respectively).
The incidence of specifically drug-related adverse events was also comparable (12 per cent and 11 per cent, respectively).
Fewer subjects in the molnupiravir group discontinued therapy due to an adverse event compared to the placebo group (1.3 per cent and 3.4 per cent, respectively).
What happens next?
Merck has already begun production of the drug in anticipation of emergency use authorisation being approved by the FDA.
“Merck has been producing molnupiravir at risk and expects to produce 10 million courses of treatment by the end of 2021, with more courses expected to be produced in 2022,” the company said.
Approximately 1.7 million treatment courses have been sold to the US government and the company has said it will offer tiered pricing to provide access around the world.
Merck will also work with generic drug manufacturers to ensure availability to low and middle-income countries.
At a White House coronavirus briefing last week, Dr Anthony Fauci said he found the results of the trial “very encouraging”, but added that it still needed close examination by the FDA.
“It is very important that this now must go through the usual process of careful examination of the data by the Food and Drug Administration both for effectiveness, but also for safety, because whenever you introduce a new compound, safety is very important,” said Dr Fauci, director of the National Institute of Allergy and Infectious Diseases.
Several other companies, including Pfizer and Roche, are studying similar drugs and are expected to report results in the coming weeks and months.
AstraZeneca is also seeking FDA authorisation for a long-acting antibody-drug intended to provide months of protection for patients who have immune-system disorders and do not adequately respond to vaccination.
Eventually, it is thought that various Covid-19 therapies will be prescribed in combination to better protect against the worst effects of the virus.
Health officials continue to stress that vaccines against Covid-19 remain the most effective tool for fighting the pandemic as they prevent infection with the virus in the first instance, rather than treating an active case of the virus.
With additional reporting from the Associated Press