- Several oral antiviral treatments for COVID-19 are currently being studied.
- Merck has received emergency use authorization for its daily pill after a clinical trial showed its drug molnupiravir reduced the risk of hospitalization or death from COVID-19 by 50 percent.
- Proponents say these types of pills would provide people with an easy and accessible way to treat symptoms of COVID-19.
- Others, however, say developing antiviral treatments for other illnesses such as the flu have proven to be more difficult than first anticipated.
For some people, treatment for COVID-19 could be as simple as taking a daily pill.
Several oral antiviral treatments for COVID-19 are in the works, while others are already available, albeit still in short supply.
In December 2021, Pfizer received emergency use authorization for Paxlovid, a COVID-19 antiviral said to reduce viral symptoms by nearly 90 percent if taken within 3 days of symptom onset.
Merck and Ridgeback Biotherapeutics have also received
Company officials said that molnupiravir reduced the risk of hospitalization or death from COVID-19 by 50 percent for trial participants with mild to moderate symptoms who took the medication compared with participants who were given a placebo.
Dr. Monica Gandhi, MPH, a professor of medicine at the University of California, San Francisco, explained the clinical trial results and their importance.
“Molnupiravir is an antiviral (nucleoside analog) originally designed to be a broad spectrum against many viruses by inhibiting viral replication,” she told Healthline. “In the test tube, molnupiravir inhibits replication of SARS-CoV-2, the agent that causes COVID-19, so it was tested first in a phase 2 trial that showed the time to viral RNA clearance decreased and a greater proportion of participants (92 percent) overall achieved viral clearance in those who received 800 mg molnupiravir twice daily.”
According to a Merck press release, molnupiravir was tested in a phase 3 trial involving participants with mild to moderate COVID-19 who had at least one risk factor for developing severe disease Researchers wanted to see whether the drug worked to prevent hospitalization or death.
An interim analysis that included 775 participants out of 1,500 enrolled were released showed that molnupiravir reduced the risk of hospitalization or death by 50 percent compared with 14 percent of participants who received a placebo.
At day 29 of the trial, no deaths were reported in patients who received molnupiravir. Eight deaths were reported in participants who received a placebo.
However, while the U.S. government has already approved the purchase of 1.7 million doses of the drug, not everyone is feeling so rosy about molnupiravir’s future.
The drug’s mechanism of action might even make the creation of new coronavirus variants more likely, wrote Dr. Michael Z. Lin, a professor at Stanford University in California, for The Washington Post.
Lin went so far as to call the drug “rather ineffective and dangerous.” The drug was only narrowly approved by FDA advisers by a vote of 13 to 10.
The World Health Organization (WHO), in recent guidance, recommended restricting the use of molnupiravir to people at the highest risk of hospitalization “given the potential long term harms associated with [the drug].”
Perhaps, for this reason, the FDA also approved emergency use of molnupiravir with caveats.
The agency recommends it only for who have mild to moderate COVID-19 in adults that is at high risk for progressing to severe disease, including hospitalization or death, and when no other COVID-19 treatment options are available.
The WHO has yet to offer guidance on Paxlovid but expects to issue recommendations on that antiviral in a future update.
Experts say antiviral treatments represent an important front in curtailing and ending the COVID-19 pandemic and its transition to an endemic disease that’s among the population but manageable.
Antiviral drugs — already used to treat HIV, hepatitis C, and the flu, among others — work by inhibiting viral replication, lowering viral loads, and making people less sick as well as potentially less likely to transmit the virus to others, experts say.
One antiviral drug, remdesivir, has been used as a COVID-19 treatment, but it’s intended for hospitalized patients with advanced cases of the disease, whereas the new antivirals could be dispensed at a pharmacy without physician intervention.
“These drugs have the potential to play a significant role in navigating the COVID-19 pandemic,” said Dr. Kelly McKee Jr., MPH, the chief scientific officer consultant on the clinical team for Revive Therapeutics’ FDA phase 3 trial for bucillamine, an antirheumatic agent being tested as an oral COVID-19 treatment.
“A ‘COVID-19 pill’ would aim to inhibit replication of the virus to the point that the body’s natural defenses can effectively combat it, reducing the severity of the infection and preventing (or at least lessening the likelihood) of progression to severe disease, hospitalization, or worse,” McKee told Healthline.
“In addition, depending upon the safety profiles of one or more of these drugs, it may be possible to prevent infections from even developing in individuals who are at high risk for becoming infected,” he said.
McKee called the development of such drugs “an important measure that complements vaccination and nonmedical interventions (e.g., masks, physical distancing, frequent handwashing) to reduce the spread of infection in communities.”
Not everyone thinks these antiviral treatments will be game-changers.
“Creating new antivirals in the time of a COVID-19 pandemic is not as easy as it looks,” said Ravi Starzl, PhD, an adjunct professor at Carnegie Mellon University in Pittsburgh and co-founder and CEO of biotech companies BioPlx and Firebreak Inc.
“Specifically, with the flu, the attempt to create antivirals to treat the flu or influenza proved to be extremely difficult, as viruses are efficient little engines of destruction,” Starzl told Healthline.
Clinically approved antiviral drugs are
Kristen Nichols, PharmD, a senior content management consultant in pediatric infectious diseases at information services company Wolters Kluwer, agreed.
“There isn’t a strong history of finding good antivirals that really change the course of upper respiratory tract infections in otherwise healthy people,” she told Healthline. “Even Tamiflu’s efficacy isn’t always clear. Generally, the best efficacy is seen if the drug can be started early in the infection before the virus has had a lot of opportunity to replicate.”
Still, early intervention is where manufacturers — and the Biden administration — are hoping to target these COVID-19 treatments.
And that’s easier to accomplish with a pill rather than an injection.
As part of the next stage of the country’s pandemic response initiatives, the White House announced the creation of “Test to Treat” locations at hundreds of pharmacy-based clinics, community health centers, long-term care facilities, and U.S. Department of Veterans Affairs facilities.
There, people would be able to get tested for COVID-19 and, if positive, receive free treatments of COVID-19 antivirals to help reduce the severity of the disease.
Right now, that antiviral will be Paxlovid, which the Biden administration has ordered 20 million doses of to help fulfill this initiative and meet demand. Whether other FDA EUA-approved antivirals will be part of this program is unclear.
That said, “the medications still need to be prescribed by an authorized prescriber who will deem the patient a good candidate to receive the medication based on the severity of symptoms and their risk factors,” Shaili Gandhi, PharmD, the vice president of pharmacy at SingleCare, told Healthline.