The drug simnotrelvir shortens symptoms for those with mild infections and is sold at a lower price in China than its main rival.
Saima Sidik
Boxes of the COVID-19 drug simnotrelvir are displayed at a manufacturing facility in Nanjing, China.Credit: VCG via Getty
There’s new hope for the average person seeking relief from COVID-19: a drug called simnotrelvir has been shown to speed recovery from mild to moderate disease by about 1.5 days1.
A clinical trial found that simnotrelvir, which is administered as a series of pills, kicks in almost immediately after being taken, reliving symptoms such as fever, cough and runny nose.
Simnotrelvir “is clearly a potent drug. It’s clearly got a positive result. And that’s welcome,” says infectious-disease pharmacologist Saye Khoo at the University of Liverpool in the United Kingdom.
The results were published today in the New England Journal of Medicine.
A COVID pill for everyone
Early in the pandemic, antiviral drugs were tested largely in people at high risk of severe COVID-19. Even now, the World Health Organization recommends that only people in high-risk groups take antivirals such as Paxlovid, the go-to COVID-19 pill in the United States and many other nations.
Now, however, “SARS-CoV-2 has already become a routine respiratory virus in general populations”, says study co-author Bin Cao, a pulmonologist at the China–Japan Friendship Hospital in Beijing. That’s why he and his colleagues decided to test simnotrelvir largely in young people with standard levels of risk.
China approves first homegrown COVID antiviral
The researchers combined simnotrelvir with a component of Paxlovid called ritonavir, which limits the breakdown of simnotrelvir. They tested this combination in more than 600 people with a median age of 35, around half of whom had at least one risk factor, such as obesity, for severe disease. None of the participants had severe COVID-19.
By the fifth day after treatment, SARS-CoV-2 levels in participants who’d taken simontrelvir had dropped by about 30-fold more than in participants who’d taken a placebo. Simnotrelvir’s ability to speed recovery in standard-risk people is reminiscent of the antiviral ensitrelvir, which was approved conditionally in Japan in November 2022.
The downsides of simontrelvir are similar to those of Paxlovid, including a notoriously bad taste and incompatibility with a range of common medications. In addition, the researchers asked trial participants to start treatment within three days of developing symptoms: a “challenging window for testing and intervention”, Khoo says.
Priced to move
Simnotrelvir has been available in China under an emergency use authorization since early last year. It’s the most popular COVID-19 antiviral in the country and costs roughly one-quarter as much as Paxlovid, Cao says. The new data might spur authorities in other countries to approve the drug, possibly after performing their own clinical trials, he adds .
But many doctors are still most concerned with preventing hospitalization and death in high-risk people, so they might want more information before they change their prescribing habits, says infectious-disease specialist William Schaffner at Vanderbilt University Medical Center in Nashville, Tennessee. “The benefit in the very patients [doctors] want to use them in has not been demonstrated,” he says.
“The bottom line is that we welcome every new drug, but none of these drugs is the last word in COVID antivirals,” Khoo says.
doi: https://doi.org/10.1038/d41586-024-00117-5
References
Cao, B. et al. N. Eng. J. Med. 390, 230–241 (2024)
Leave a Reply