A panel of U.S. health advisors on Tuesday narrowly backed a closely watched COVID-19 pill from Merck, setting the stage for a likely authorization of the first drug that Americans could take at home to treat the coronavirus, reports AP News.
Risks of antiviral drugs
The Food and Drug Administration panel voted 13-10 that the antiviral drug’s benefits outweigh its risks, including potential birth defects if used during pregnancy.
The recommendation came after hours of debate about the drug’s modest benefits and potential safety issues. Most experts backing the treatment stressed that it should not be used by anyone who is pregnant and called on the FDA to recommend extra precautions before the drug is prescribed, such as pregnancy tests for women of child-bearing age.
The vote specifically backed the drug for adults with mild-to-moderate COVID-19 who face the greatest risks, including older people and those with conditions like obesity and asthma.
Toxicity to human fetuses
For many panelists, the modest effect wasn’t enough to outweigh the drug’s potential toxicity to human fetuses.
“Given the large potential population affected, the risk of widespread effects on potential birth defects has not been adequately studied,” said Dr. Sankar Swaminathan of the University of Utah School of Medicine, who voted against the drug.
FDA scientists told the panelists earlier Tuesday that company studies in rats showed the drug caused birth defects when given at very high doses. FDA staffers concluded the data “suggest that molnupiravir may cause fetal harm when administered to pregnant individuals.”
The agency is weighing a blanket restriction against any use in pregnant women or allowing doctors to use the drug in rare cases. Some panelists said that option should be left open for pregnant mothers who have high-risk COVID-19 and may have few other treatment options.
Error in the genetic code
Merck’s drug inserts tiny errors into the coronavirus’ genetic code to stop it from reproducing. That genetic effect has raised concerns that the drug could spur more virulent strains of the virus. FDA regulators said Tuesday that risk is theoretical but many panelists said it should be carefully tracked in follow-up studies.
Antiviral pills have long been seen as a key advance beyond currently used antibody drugs, which must be injected or infused by health professionals. But given the shortcomings of Merck’s data, several experts said they would prioritize patients to receive the older drugs.
How effective are these antiviral drugs?
The drug, molnupiravir, could provide a much-needed weapon against the virus as colder weather pushes case counts higher and U.S. officials brace for the arrival of the new omicron variant.
Merck hasn’t specifically tested its drug against the new variant but said it should have some potency based on its effectiveness against other strains of coronavirus.
“With no data saying it works with new variants, I really think we need to be careful about saying that this is the way to go,” said Dr. David Hardy of Charles Drew University School of Medicine and Science, who ultimately voted to back the drug.
Merck said final study results showed molnupiravir reduced hospitalization and death by 30% among adults infected with the coronavirus, when compared with adults taking a placebo. That effect was significantly less than the 50% reduction it first announced based on incomplete results.
Pfizer’s drug
Pfizer’s drug is part of a decades-old family of antiviral pills known as protease inhibitors, a standard treatment for HIV and hepatitis C. They work differently than Merck’s pill and haven’t been linked to the kind of mutation concerns raised with Merck’s drug.
Pfizer said this week that its drug shouldn’t be affected by the omicron variant’s mutations.
The U.S. government has agreed to purchase 10 million treatment courses of Pfizer’s drug, if it’s authorized. That’s more than three times the government’s purchase agreement with Merck for 3.1 million courses of molnupiravir.
Did you subscribe to our daily Newsletter?
It’s Free! Click here to Subscribe
Source: AP News
