A study from U.K. and South African researchers linked Merck’s COVID-19 antiviral to mutations of the virus.
The study, published in the journal Nature, analyzed data from COVID-19 patients treated with Merck’s molnupiravir drug and those who were not.
While the drug induces mutations in the virus to destroy it, there was concern that “if some patients treated with molnupiravir do not fully clear SARS-CoV-2 infections, there could be the potential for onward transmission of molnupiravir-mutated viruses,” according to the study.
The researchers found that mutations of COVID-19 found in 2022 were consistent with the mutations brought about by Merck’s antiviral.
Greater rates of the mutation were seen in countries with wider distribution of the drug, such as Australia.
“Importantly, the divergence of the molnupiravir mutation spectrum from standard SARS-CoV-2 mutational dynamics might allow the virus to explore the fitness of distinctive parts of the possible genomic landscape to those it is already widely exploring in the general population,” expanding the diversity and variety of the virus.
“Molnupiravir-induced mutation could also potentially allow infections to persist for longer by creating a more varied target for the immune system,” the study explained.
The researchers concluded, “We recommend that public health authorities perform continued investigations into the effects of molnupiravir in viral sequences, and the transmissibility of molnupiravir-derived lineages.”
Reporting from The Hill:
When reached for comment, Merck questioned the strength of the evidence presented by the researchers. “The authors assume these mutations were associated with viral spread from molnupiravir-treated patients without documented evidence of that transmission. Instead, the authors rely on circumstantial associations between the region from which the sequence was identified and timeframe of sequence collection in countries where molnupiravir is available to draw their conclusions,” said the company. “Furthermore, these sequences were uncommon and were associated with sporadic cases. As noted by the authors, there are limitations to the analyses conducted in this study, which are described in more detail in the manuscript,” Merck added. “These data must be considered in the context of all available clinical and non-clinical molnupiravir data.”
