Merck’s Covid drug is causing new virus mutations, study warns

A covid drug that has just been approved in virus-stricken China causes the coronavirus to mutate in new ways, a study warns.

US and UK researchers identified the new mutations in viral samples taken from dozens of patients who received Merck’s antiviral Lagevrio.

Alterations to the virus did not make it more deadly or infectious, but experts say it undermines the risk of drugs that work by playing with Covid’s genetic code.

While Lagevrio has rarely been used in the US or UK, it has just been licensed for use in China, where officials have relied on vaccines and poor treatment amid a devastating wave of the virus.

Officials had been warning for months that sky-high infection rates in China, with experts fearing that 250 million infections hit the nation in December alone, could give rise to a dangerous new variant. And that was before the latest findings.

Concerns that Lagevrio could stimulate mutations were raised when it received clearance from the Food and Drug Administration (FDA) in late 2021.

The drug works by creating mutations in the Covid genome that prevent the virus from replicating in the body.

While initially considered a breakthrough, Pfizer’s Paxlovid has surpassed Lageviro as the Covid antiviral of choice worldwide, sidelining Merck’s drug over the past year.

The latest study has been published online as a preprint and has not been peer reviewed.

The team, which included experts from the Francis Crick Institute, Imperial College London and the University of Cambridge, analyzed 13 million RNA sequences from the virus that causes covid.

They analyzed the nucleic composition of the RNA strands to look for signs that the virus mutated due to the drug.

In hundreds of samples, they found evidence that the drug had caused replication. Almost all of the detections were made in samples collected in 2022, the year it became globally available, suggesting that Lagevrio is to blame.

“Some patients treated with molnupiravir may not completely clear SARS-CoV2 infections, with the potential for transmission of molnupiravir-mutated viruses,” the researchers wrote.

Rahway, New Jersey-based Merck disputed the report, saying there is no evidence it contributed to Covid variants, or could do so in the future.

“There is no evidence to indicate that any antiviral agent contributed to the emergence of circulating variants,” Merck spokesman Robert Josephson said. Bloomberg.

“Based on the available data, we do not believe that Lagevrio (molnupiravir) is likely to contribute to the development of significant new coronavirus variants.”

But, the results raise the possibility of worrisome future strains of the virus emerging.

Some experts immediately pointed to the drug’s potential to cause troubling mutations when it first made headlines in late 2021.

Dr. William Haseltine, known as one of the world’s leading experts in human genome analysis, warned in late 2021 that the way the drug worked opened the door to danger.

“You are putting into circulation a drug that is a potent mutagen at a time when we are deeply concerned about new variants,” he said. Forbes.

He added: “I can’t imagine doing anything more dangerous.”

‘If I were trying to create a new, more dangerous virus in humans, I would feed a subclinical dose [of molnupiravir] to infected people,’ he continued.

The FDA approved the drug for use in December 2021. The approval was controversial among some experts due to concerns about virus mutations.

However, it did show the ability to reduce hospitalizations and deaths from the virus by 50 percent in clinical trials.

Soon after, Pfizer’s Paxlovid received approval. More than 90 percent effective against hospitalizations and deaths, and without many of the concerns about the virus’s mutations, the latter quickly became America’s drug of choice to fight covid.

Although molnupiravir received little use in much of the Western world, generic versions of it were used in less developed countries.

It was also often used to treat covid patients in Australia.

There were also fears in 2021 that the vaccines themselves could stimulate the viruses to mutate.

Due to the immunity gap, where the majority of the population is vaccinated but a small portion remains unvaccinated, the virus could find a way to mutate around protection from injections.

This occurred as the vaccine-resistant Omicron strain emerged in late 2021.