2nd COVID Pill Is Headed Our Way, but With Caveats

US health regulators on Thursday authorized the second pill against COVID-19, providing another easy-to-use medication to battle the rising tide of omicron infections. The Food and Drug Administration's authorization of Merck's molnupiravir comes one day after the agency cleared a competing drug from Pfizer. That pill, Paxlovid, is likely to become the first-choice treatment against the virus, thanks to its superior benefits and milder side effects, per the AP. As a result, Merck's pill is expected to have a smaller role against the pandemic than predicted just a few weeks ago. Its ability to head off severe COVID-19 is much smaller than initially announced, and the drug label will warn of serious safety issues, including the potential for birth defects.

The FDA authorized Merck's drug for adults with early symptoms of COVID-19 who face the highest risks of hospitalization, including older people and those with conditions like obesity and heart disease. The UK first authorized the pill in early November. The US will pay about $700 for each course of Merck's drug, known as molnupiravir, which requires patients to take four pills twice a day for five days. Molnupiravir inserts tiny errors into the coronavirus's genetic code to slow its reproduction. That genetic effect has raised concerns that the drug could cause mutations in human fetuses and even spur more virulent strains of the virus. But FDA scientists said the variant risk is largely theoretical, as people take the drug for such a short period of time. The Merck drug will carry a warning against use during pregnancy.

The Pfizer pill works differently and doesn't carry the same risks. Additionally, Pfizer's drug was roughly three times more effective in testing, reducing hospitalization and death by nearly 90% among high-risk patients, compared with 30% for Merck's. Some experts question whether there will be much of a role for the Merck drug in the US. "To the extent that there's an ample supply of Pfizer's pill, I think it won't be used," said Dr. Gregory Poland of the Mayo Clinic of molnupiravir. For now, the FDA decision provides another potential option against the virus that has killed more than 800,000 Americans. Federal officials have agreed to purchase enough of the drug to treat 3.1 million people.

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