Merck & Co’s antiviral LaGevrio is linked to specific genetic changes in the virus that causes COVID-19, researchers said, raising questions about whether the drug has the ability to limit how quickly the coronavirus mutates. .
Viral samples from patients who took the drug showed a “signature mutation profile,” meaning the changes were triggered by the drug, the authors said Monday in the journal Nature. The findings add weight to earlier work by the same team of researchers that suggested drug-induced Covid mutations were spreading in some populations, though not in large numbers.
“We can’t say whether this drug makes it more or less likely that a related variant will develop – that’s a question we can’t answer,” Theo Sanderson, lead author of the study and a researcher at the Francis Crick Institute. Are. London, said in an interview. Researchers said more studies are needed. “Regulators need to weigh the potential risks as well as the benefits of using the drug.”
When researchers first published findings about the mutations from Merck’s drug in February, the company refuted the idea that Lagevrio was causing the problematic new variants. Based on data at the time, the drug maker said it did not believe its treatment was likely to contribute to the mutation.
Laegvrio, also known as molnupiravir, works by creating mutations in the COVID genome to stop the virus from replicating, reducing its ability to cause severe disease. The authors said the emergence of treatment-associated mutation patterns suggests that some versions of the virus survive and continue to spread after exposure to the drug. They cautioned that the drug-induced mutations they found have not yet caused the new strain of Covid to circulate widely.
Merck’s drug has long been controversial because it can cause genetic mutations. Pregnant women are discouraged from taking it, and the Food and Drug Administration recommends not using Laguevrio during pregnancy or breastfeeding. This medicine is not authorized for patients under 18 years of age because it may affect bone and cartilage development.
It is often given to people who are taking Pfizer Inc. Cannot take Paxlovid, which interacts with other common medications. So far, Paxlovid has fared better than Lagravio. Paxlovid had sales of about $19 billion in 2022, while Lagavrio had sales of about $5.7 billion.
In the most recent study, researchers from the US and UK combed a database containing nearly 15 million Covid genomes globally. After Lagaverio came on the market in 2022, they noticed an increase in a mutation pattern that appeared to be linked to the drug. Earlier studies by the same researchers showed that the pattern was localized in countries using LaGavrio.
“The observation that molnupiravir treatment left a visible mark in global sequencing databases will be an important consideration for assessing the effects and evolutionary safety of this drug,” the researchers said in the study.