The antiviral molnupiravir may be shaping the evolution of the virus behind COVID-19, but we still don't know what this means for transmission or the emergence of variants.
An antiviral drug used to treat COVID-19 may be driving the virus that causes the disease to evolve, a new study suggests.
Scientists analyzed more than 15 million SARS-CoV-2 genomes — genetic material from the virus that causes COVID-19 — and found that molnupiravir induces a"mutational signature" that, if the virus isn't completely obliterated by a course of the drug, can be transmitted to other people. Molnupirivar works by causing mutations in the SARS-CoV-2 genome that prevent the virus from replicating.
The findings could help regulators to assess the risks and benefits of using the drug, but experts told Live Science that many questions remain unanswered. Indeed, Sanderson said from this data alone, it is difficult to quantify how common it is for molnupiravir-derived lineages of SARS-CoV-2 to spread between people. That's because, if a single sample of the virus with this molnupiravir signature shows up in a database but doesn't have any close relatives, scientists can't easily tell if it came from someone treated with the drug or another person infected further down the line.—Omicron's not the last variant we'll see.