Introduction
High-risk COVID-19 patients are given Paxlovid so they do not have to go to the hospital. But there have been cases of COVID-19 rebound after a five-day course of treatment. This means that the patient's symptoms come back or they test positive for the virus again. The Centers for Disease Control and Prevention (CDC) says that people who have a COVID-19 return should start isolating themselves again and do it again. Even though there is a chance of rebound, the benefits of taking Paxlovid still beat the risks, as it has been shown to cut the risk of hospitalization and death by almost 90 % in high-risk people who have not been vaccinated. Studies are still being done to track how often Paxlovid works and how well it works.
What Is Paxlovid?
Paxlovid is a prescription oral antiviral drug that lowers the risk of hospitalization and death for people with mild-to-moderate COVID-19 (coronavirus disease).
Paxlovid is a Pfizer oral therapy suggested for older, immunocompromised, unvaccinated persons with a pre-existing medical condition, such as diabetes or heart disease, that puts them at risk of hospitalization from COVID-19. Paxlovid is particularly successful in preventing severe COVID-19 in these persons.
Paxlovid is made up of two different drugs. One such medicine is Nirmatrelvir, a protease inhibitor that prevents the coronavirus from multiplying in the body. Ritonavir, the second component of Paxlovid, boosts Nirmatrelvir by reducing the rate at which the liver metabolizes it. Typically, two Nirmatrelvir pills and one Ritonavir pill are taken simultaneously in the morning and then again in the evening, beginning within a few days of experiencing COVID-19 symptoms or testing positive. The entire course of treatment lasts five days.
It is also important to know that Ritonavir can slow down the rate at which the body metabolizes a number of other drugs, which could increase the blood levels of those drugs. The U.S. (United States) Food and Drug Administration says that some of these drugs are statins, oral contraceptives, and HIV (human immunodeficiency virus) treatments.
Who Is Eligible to Take Paxlovid?
Paxlovid is not suitable for everyone. It is now advised for adults and children aged 12 years and up who weigh at least 88 pounds (40 kilograms). Paxlovid therapy may be considered if:
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Tested positive for COVID-19.
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Having mild to moderate symptoms.
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First noticed signs less than five days ago.
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People with a compromised immune system are at a higher risk of acquiring severe COVID-19 sickness.
How Does Plaxovid Interact With Other Drugs?
Because of the Ritonavir component of the combination, Ritonavir-boosted Nirmatrelvir exhibits substantial drug-drug interactions. To raise Nirmatrelvir exposure to a concentration effective against SARS-CoV-2, Ritonavir, a potent CYP3A inhibitor and P-glycoprotein inhibitor, is required. However, it may increase the concentrations of certain concurrent drugs, raising the risk of serious and occasionally fatal drug toxicities. Ritonavir is also an inhibitor, inducer, and substrate of a number of additional drug-metabolizing enzymes.
Since Ritonavir-boosted Nirmatrelvir is the only highly effective oral antiviral for COVID-19 therapy, drug-drug interactions can be controlled safely and should not stop it from being used.
The treatment course for COVID-19 with Ritonavir-boosted Nirmatrelvir is five days. After starting Ritonavir, CYP3A4 inhibition occurs quickly, with maximum inhibition happening within 48 hours. After stopping Ritonavir, 70 to 90 percent of CYP3A4 inhibition resolves in two to three days. Because the time to resolution of inhibition varies depending on factors such as the patient's age, resolution may take longer in some individuals, such as elderly folks. Ritonavir's induction qualities are less likely to be clinically meaningful when administered for five days than when used continuously (e.g., in people who take HIV protease inhibitors).
Both Nirmatrelvir and Ritonavir are CYP3A substrates. Thus, Ritonavir-boosted Nirmatrelvir should not be administered within two weeks after a potent CYP3A4 inducer (e.g., St. John's wort, Rifampin). Ritonavir-boosted Nirmatrelvir is not recommended in this situation because the delayed offset of enzyme induction can diminish Nirmatrelvir and Ritonavir concentrations, rendering the treatment ineffective against SARS-CoV-2. Instead, alternative therapy for COVID-19 is offered.
What Exactly Is COVID-19 Rebound?
COVID-19 rebound occurs when persons with COVID-19 recover and again experience symptoms two to eight days later. They may also retest positive. COVID-19 rebound has been observed in both those who got COVID-19 treatment and those who did not. Paxlovid is one of the numerous medications related to COVID-19 rebound. This is an antiviral medication, and it is the most commonly used drug to treat COVID-19.
How Common Is the Rebound?
Experts are still trying to figure out how common Paxlovid rebound is. Because this topic is still being researched, the information shown here may change. This is the most recent information available as of August 2022. When Paxlovid was first granted Emergency Use Authorization (Eua), manufacturer Pfizer reported that one to two percent of those using Paxlovid experienced COVID-19 Rebound. These rates were comparable to those who took a placebo (a pill containing no medication) during clinical trials. More recent data suggests that Paxlovid rebound may occur more frequently. However, it is very uncommon. According to a preliminary study, approximately four percent of people who use Paxlovid experience COVID-19 rebound within seven days after finishing treatment.
Why Do Patients Experience Rebound?
At this time, no one knows why the COVID-19 rebound happens. The Centers for Disease Control and other organizations are looking at data and reports about rebound to learn more about it. A recent study says that the rebound may happen when people have a strong immune response to COVID-19. Other studies are also being conducted to understand better why rebound occurs and how frequently people with rebound infect others.
How Significant Are the Symptoms of Rebound From COVID-19?
In most cases, the symptoms of COVID-19 recurrence are less severe than during the initial infection. According to findings from recent studies, patients who have rebound have a very low risk of having severe COVID-19.
Who Is Susceptible to COVID-19 Rebound?
Still, scientists are trying to figure out if some people are more likely to relapse than others. Several researchers found that rebound cases were more likely to have the following traits:
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People who have medical disorders that increase their risk of severe COVID-19 sickness and rebound.
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People who have received organ transplants.
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Those who smoke.
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People who take immune-suppressing medicines.
Conclusion
The rebound occurs when a person's COVID-19 symptoms worsen after initially improving after taking Paxlovid. This usually occurs between two and eight days following a person's last dose. Experts are unsure who is more vulnerable to this. Taking another course of Paxlovid to treat rebound symptoms is not advised. If the symptoms worsen, call the healthcare physician to discuss the subsequent measures to be taken for the treatment.
