A new COVID-19 treatment option is available in the form of a pill. Antiviral drugs, Paxlovid and molnupiravir, were developed by pharmaceutical companies Pfizer and Merck to prevent people who are at high risk from becoming severely ill after infection with the SARS-CoV-2 virus, the virus that causes COVID-19. The Food and Drug Administration (FDA) issued emergency use authorizations in late 2021 for both medications. The pills are available by prescription from some Milwaukee-area pharmacies.

How Do the COVID-19 Pills Work?

Paxlovid and molnupiravir are antivirals that work by stopping the viral replication process. This reduces a person’s viral load and lessens the severity of their symptoms. However, the way the drugs function is slightly different.

Paxlovid is a protease inhibitor because it blocks a part of the virus’ life cycle. Protease inhibitors bind to the enzyme the virus uses to replicate and prevent the production of new viral particles. Molnupiravir is a nucleoside analogue, which means it stops the viruses’ genetic material from being accurately replicated, rendering new viral particles noninfectious. 

Clinical trials of both drugs were so successful, they were stopped early. Results showed the pills were much more effective than placebos. Pfizer’s clinical trial found Paxlovid reduced a person’s risk of hospitalization by 89% when given within three days of symptom onset. Merck’s clinical trial showed molnupiravir cut the rate of hospitalization or death by 30% when the drug was given within five days of symptoms onset. 

It is important to note that both of these clinical trials were conducted in a small number of patients, and both of these drugs remain investigational in nature. They are authorized for emergency use but are not FDA-approved, and the full extent of risks and benefits may not yet be determined.

Both pills require a five-day course of treatment. Most people who are prescribed Paxlovid take three tablets at the same time, twice a day (there is a dose reduction for people with moderate kidney disease.)  People prescribed molnupiravir need to take four capsules twice a day.

Who Is Eligible for the COVID-19 Pills?

Not everyone who tests positive for COVID-19 will be able to get a prescription for Paxlovid or molnupiravir. Per the FDA, Paxlovid and molnupiravir are only authorized for use in people who have tested positive for COVID-19, are experiencing mild to moderate disease and are at a high risk for progression to severe disease. Paxlovid is authorized for people ages 12 and older. Molnupiravir is authorized for people ages 18 and older.

Neither pill is intended or authorized for people who require hospitalization for severe COVID-19. They are also not intended for the prevention of COVID-19 in someone who was exposed to the virus.

If you tested positive for COVID-19 in the last five days and have questions about your eligibility or risk factors, talk to your doctor. 

These medications are widely available. If your positive test was done at a Froedtert & the Medical College of Wisconsin lab location, your doctor is part of the Froedtert & MCW health network and you are eligible for this treatment, a nurse will reach out to you through MyChart. Patients who do not use MyChart will receive a phone call. If your positive test result was from an at-home test or external lab, you should contact your Froedtert & MCW primary care provider or schedule an E-Visit to be referred for treatment. 

How Are COVID-19 Pills Different Than Monoclonal Antibody Therapy?

Monoclonal antibody therapy is a treatment given by infusion that supplies the body with man-made antibodies to fight COVID-19. While both the antiviral pills and monoclonal antibody therapy are effective treatments for COVID-19, the mechanism by which the treatments accomplish this is different. 

The antibodies target the virus’ spike protein or other surface proteins by binding to the virus particles in order to block them from entering the body’s cells. The antiviral pills work inside the cells to inhibit viral replication.

Both treatments should be given as soon as possible after a positive COVID-19 test, but there is more flexibility with when monoclonal antibody therapy can be prescribed; it is available within 10 days of symptom onset, while the antiviral pills can only be prescribed within five days of symptom onset. 

Which COVID-19 Treatment Is Right for Me?

Based on your health history and current medications, your health care team will determine which COVID-19 treatment is best for you. This will also depend on availability, as the Wisconsin Department of Health and Human Services oversees the distribution of supplies and determines how much of each drug is sent to Wisconsin hospitals. 

“Between monoclonal antibody therapy and the two different COVID-19 pills, we have been able to reach out to nearly 95% of eligible patients and offer one of these therapies,” said Mark Lodes, MD, a Froedtert & MCW internal medicine and pediatric physician. Dr. Lodes is also vice president and chief medical officer for Froedtert & MCW Population Health and Medical Education.

Led by Dr. Lodes, the Froedtert & MCW Population Health team developed a centralized process to make it easier for patients to receive the right COVID-19 treatment for them and for providers to prescribe it. When a provider submits a referral, the database matches each patient with the best treatment for them, based on risk factors, and in some cases, lab results, which are ordered the same day.

“If you did a home test and got a positive result, all you need to do is share that result with your doctor’s office,” Dr. Lodes said. “If you tested with us and got a positive result, we automatically receive the alert. In both cases, this kicks off our internal evaluation process of eligible patients. If you are eligible for one of the COVID-19 antiviral medications or monoclonal antibody therapy, we’ll reach out to you with the appropriate treatment option.”

Many health networks have moved toward a similar centralized system because it simplifies and speeds up the dispensing process, while maximizing the ability to treat as many people as possible.

What Are the Side Effects of the COVID-19 Pills?

Pfizer’s Paxlovid is a combination of two drugs, nirmatrelvir and ritonavir. Ritonavir is widely known for its use in HIV medications. It is not active against COVID-19, but it acts as a boosting agent to increase the levels of nirmatrelvir in the body to fight the virus that causes COVID-19. Many widely used medications for chronic conditions, like blood thinners or antidepressants, have known drug interactions with ritonavir.

“Some of these drug interactions are manageable by adjusting doses of the other medications, when possible,” said Deanna Olexia, RPh, antimicrobial stewardship coordinator for the Froedtert & MCW health network. “But when this isn’t an option or when the interactions could be significant, we direct patients toward an alternative therapy.”

Paxlovid isn’t recommended for people with severe kidney or liver disease.

Molnupiravir doesn’t have any known drug interactions, but based on the research available, it is not recommended for use during pregnancy. Women of child-bearing age undergoing treatment are asked to use contraception for the duration of the treatment and through four days after the last dose. Men who are sexually active should use contraception during treatment and for three months after the last dose. 

Your health care team will keep track of all of this for you and make sure you are matched with the best treatment for you.

Do I Need to Take the COVID-19 Pill if I’m Not Feeling Sick?

The COVID-19 pills are prescribed early in the disease process, within five days of a positive COVID-19 test. People are only eligible if they have symptoms, but during this timeframe, it is possible you will not feel severely ill, or you may have milder symptoms. While the decision to move forward with treatment is yours, it is important to understand why your provider recommended the treatment for you.

“If you were prescribed a COVID-19 pill, you are part of a group of people that is at risk for worsening disease,” Olexia said. “Consider the impact this would have on you or your family and take into account the information we have about the medication so far. These medications appear to be quite effective and safe, and they may prevent you from becoming more sick or needing to be hospitalized.”

If you’re prescribed one of the COVID-19 pills, you are still asked to isolate while you are undergoing treatment, following current CDC guidelines.

Are Vaccinations Against COVID-19 Still Necessary With COVID-19 Pills?

The COVID-19 vaccines lower your risk of becoming infected and of spreading the virus. The pills are not a substitute for vaccination because they do not prevent COVID-19, they are a treatment. 

“Public health mitigation measures like vaccines, face masks and social distancing are still the best ways to prevent you from getting admitted to the hospital for COVID-19,” Dr. Lodes said. “If you are infected, these new medications are a potential lifesaving therapy.”

To learn more about COVID-19 care and testing options, visit https://www.froedtert.com/coronavirus

Add new comment

on December 16, 2022 - 1:12 pm

Can you take this drug if you are on blood thinners

on December 16, 2022 - 3:43 pm

Thanks for your question. Since everyone's medical situation is different, we recommend people check with their primary care provider to determine if COVID-19 pills are appropriate to take for people taking blood thinners.

on July 18, 2022 - 2:19 pm

Can both Paxlovid & the Monoclonal Antibody treatment be taken at the same time?

on August 17, 2022 - 3:49 pm

Thanks for your question. There is a maximum time limit of 5 days from symptom onset to start of antivirals and of 7 days for monoclonal antibody. From a practical perspective there is a very limited window of opportunity to change between therapies.

on July 18, 2022 - 10:52 am

Can you take monoclonal antibodies treatment if you take paxlovid. Is there any interactions between the the two.

on July 2, 2022 - 1:16 pm

If Paxlovid fails or there is rebound, can a monoclonal antibody infusion still be given?

on July 7, 2022 - 9:33 am

Thanks for your question, Jill. While there are no restrictions to changing between therapy options, there is a maximum time limit of 5 days from symptom onset to start of antivirals and of 7 days for monoclonal antibody. Most patients are testing and being treated around day 2-3 of their illness, so from a practical perspective there is a very limited window of opportunity to change between therapies.

on March 7, 2022 - 11:27 am

This was a lot of information to digest, It was very interesting to read.