Merck's COVID pill: What we know about the antiviral's effectiveness, eligibility and cost

Merck's COVID pill could soon be available to help those infected combat the virus. Here's what we know.

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Merck's COVID antiviral drug molnupiravir could cut serious illness and hospitalization.


As the omicron COVID variant spreads across the US, we may soon have more tools to fight off serious infection. The US Food and Drug Administration is expected to soon approve the molnupiravir antivirus pill from Merck and Ridgeback Biotherapeutics, following a recommendation last week by an FDA advisory committee for emergency use. A COVID pill from Pfizer is also expected to receive FDA approval this year.

Merck said its pill can reduce the risk of hospitalization and death by 30% and can be taken orally at home. Vaccines can help check the virus' spread and fend off its most dangerous strains. But if you do get COVID-19, you'll want ways to fight the infection, including the possibility of a pill you can take at home. That's the goal of Merck and Ridgeback in the development of their antiviral pill to fight coronavirus.

New data from Johns Hopkins University shows the US has had 49 million confirmed cases and that 789,745 have died from the coronavirus. While the available COVID-19 vaccines are highly effective, millions of Americans have not been vaccinated. According to a September report from the Centers for Disease Control and Prevention, unvaccinated people are over 10 times more likely to be hospitalized and die from the disease than fully vaccinated people.

Here's what we know about Merck's antiviral drug right now. We'll keep this story updated as more details emerge. For more on COVID-19, here's the latest on vaccine mandates, how you can get free COVID-19 test kits soon and how to get a free ride to your booster appointment.

Watch this: What to do if you lose your vaccination card, and how to never lose it again

What is Merck's COVID pill?

Merck's antiviral pill can help those infected with the COVID-19 virus, lessening the effects of the illness, regardless of whether you are vaccinated or not. And the oral drug is expected to be effective against variants, including the new omicron virus mutation.

Antiviral drugs, however, won't replace the need for vaccines. Health officials see the two working side by side to keep infections in check: The vaccines prevent infection and lessen the severity of illness if you get infected. The antiviral can lessen the effects of the illness, regardless of vaccination status.

Merck isn't the only pharmaceutical company making an antiviral pill for COVID-19. But Merck's pill is farther along in the process and could become the first antiviral drug approved to be taken orally and at home with a prescription. (See below for more on other antiviral drugs.)

A study of molnupiravir showed it cut the risk of hospitalization or death by 30% when given to nonhospitalized adult patients within five days of their symptoms starting, according to Merck.

When will Merck's oral pill be available in the US?

The drug could soon be available if federal regulators don't turn up any problems, The New York Times reported

On Nov. 30, an FDA advisory panel recommended the FDA approve the authorization. In anticipation of approval, Merck said it expects to produce 10 million courses by the end of 2021.

Is it just one COVID antiviral pill or a bunch of them?

A course of the drug would require taking molnupiravir twice a day for five days. In total, a course would include taking 40 pills.

Does swallowing a pill mean you don't need a COVID-19 vaccine?

Vaccines and antiviral drugs could work together but serve different purposes. A vaccine is intended to provide powerful protection to keep you from getting COVID-19. An antiviral drug helps your body fight a virus if you get infected.

"The vaccine is our first-line tool for preventing hospitalization," said Yale Medicine infectious diseases specialist Dr. Jaimie Meyer. "Some people might say, 'I'm not getting vaccinated because I'll have access to these medications,'" she said, "but you can't trade one for the other."

For example, chickenpox is a common virus that can be prevented in large part through vaccination. However, there are still cases of chickenpox that affect both vaccinated and unvaccinated people, and an antiviral medication may still be prescribed as a treatment. Taking that antiviral pill against the chickenpox won't stop you from erupting into blisters all over your body, running a high fever, itching like crazy or being contagious. It won't keep you from scarring, either. But it can help you recover a few days faster than you would have if you didn't take the medication. 

Will Merck's antiviral treatment be free?

That's the plan. Merck said the US government will buy 3.1 million courses of the drug to provide for free if and when it is approved, much as it does now with the three approved vaccines from Pfizer, Moderna and Johnson & Johnson. 

What do we know about eligibility for Merck's antiviral pill?

In its tests, Merck's molnupiravir pill was given to people who were unvaccinated and had tested positive with mild to moderate COVID-19 but were not hospitalized. 

According to The New York Times, the drug may be available at first to those who have tested positive and are at higher risk of serious illness. The FDA and CDC will have the final say about who will be eligible for the pill.


Antiviral drugs will work side by side with vaccines.

Natalie Weinstein/CNET

What do we know about the COVID pill's side effects?

A Merck spokesperson said the incidence of drug-related side effects during the drug's trials was comparable between the group that received molnupiravir and the one that took the placebo -- 12% and 11%, respectively.

Which other antiviral COVID drugs are there?

According to a New York Times tracker, one other antiviral drug has so far been approved for COVID-19 treatment: remdesivir from Gilead Sciences, which was approved in October 2020. The Times is tracking 32 other possible drugs in different stages of development and approval.

Unlike Merck's drug, remdesivir requires a health care professional to give you the medication intravenously, through a needle. One dose can take 30 to 120 minutes to administer, and the drug is given once a day for five to 10 days, depending on the number of doses required.

For more on COVID-19, here's the latest on COVID-19 vaccines for kids, what to know about mixing and matching vaccines and what is happening with booster shots.

The information contained in this article is for educational and informational purposes only and is not intended as health or medical advice. Always consult a physician or other qualified health provider regarding any questions you may have about a medical condition or health objectives.