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  1. Development & Approval Process | Drugs

Drug Trials Snapshots: PAXLOVID

HOW TO USE THIS SNAPSHOT
The information provided in Snapshots highlights who participated in the key clinical trials that supported the original FDA approval of this drug, and whether there were differences among sex, race, age, and ethnic groups. The “MORE INFO” bar shows more detailed, technical content for each section. The Snapshot is intended as one tool for consumers to use when discussing the risks and benefits of the drugs.

LIMITATIONS OF THIS SNAPSHOT:
Do not rely on Snapshots to make decisions regarding medical care. Always speak to your healthcare provider about the benefits and risks of a drug.

Some of the information in this Snapshot is for presentation purposes and does not represent the approved conditions of use of this drug. Refer to the PAXLOVID Prescribing Information for all of the approved conditions of use of this drug (e.g., indication(s), population(s), dosing regimen(s), safety information).

Snapshots are limited to the information available at the time of the original approval of the drug and do not provide information on who participated in clinical trials that supported later approvals for additional uses of the drug (if applicable).

PAXLOVID (nirmatrelvir/ritonavir)
PAKS-loh-vid
Pfizer
Approval date: May 25, 2023


DRUG TRIALS SNAPSHOT SUMMARY:

What is the drug for?

PAXLOVID is a prescription medicine that is used to treat mild-to-moderate coronavirus disease 2019 (COVID-19) in adults who are at high risk for progression to severe COVID-19, including hospitalization or death.

How is this drug used?

PAXLOVID consists of two medicines: nirmatrelvir tablets and ritonavir tablets that are both taken together two times each day for five days.

Who participated in the clinical trials?

The efficacy of Paxlovid was primarily supported by the results of the EPIC-HR clinical trial (Trial 1/NCT04960202). EPIC-HR was a randomized, double-blind, placebo-controlled clinical trial studying Paxlovid for the treatment of non-hospitalized symptomatic adults with a laboratory confirmed diagnosis of SARS-CoV-2 infection. Patients were adults 18 years of age and older with a prespecified risk factor for progression to severe disease or were 60 years and older regardless of prespecified chronic medical conditions. All patients had not received a COVID-19 vaccine and had not been previously infected with COVID-19. The trial was conducted at 189 sites in 19 countries including the United States.

How were the trials designed?

There were two trials that evaluated benefits and side effects of PAXLOVID in patients with COVID-19. Each trial was designed differently.

Trial 1 enrolled unvaccinated outpatient adults who were at high risk for severe COVID-19. Patients received at random either PAXLOVID or placebo tablets twice a day for five days. Neither the patients nor the investigators knew which treatment was given. The benefit was evaluated by comparing the rates of COVID-19 related hospitalization or all-cause death within 28 days in the PAXLOVID-treated group to the placebo-treated group.

Trial 2 enrolled unvaccinated outpatient adults without any risk factors for severe COVID-19 and vaccinated outpatient adults with at least one risk factor for severe COVID-19. Patients received at random either PAXLOVID or placebo tablets twice a day for five days. Neither the patients nor the investigators knew which treatment was given. The benefit was evaluated by comparing time to sustained COVID-19 symptom alleviation through 28 days in the PAXLOVID-treated group to the placebo-treated group.


DEMOGRAPHICS SNAPSHOT:

Figure 1 summarizes how many male and female patients were enrolled in the clinical trial used to evaluate the efficacy of PAXLOVID.

Figure 1. Baseline Demographics by Sex

Pie chart summarizing how many male and female patients were in the clinical trial. In total, 1069 (51%) male patients and 1044 (49%) female patients participated in the clinical trial.

Source: Adapted from FDA Review

Figure 2 summarizes the percentage of patients by age enrolled in the clinical trial used to evaluate the efficacy of PAXLOVID.

Figure 2. Baseline Demographics by Age

Pie chart summarizing how many patients by age were in the clinical trial. In total, 1045 (50%) patients between 18 and 44 years of age, 630 (30%) patients between 45 and 59 years of age, 175 (8%) patients between 60 and 64 years of age, 199 (9%) patients between 65 and 74 years of age, and 64 (3%) patients 75 years of age and older participated in the clinical trial.

Source: Adapted from FDA Review

Figure 3 summarizes the percentage of patients by race enrolled in the clinical trial used to evaluate the efficacy of PAXLOVID.

Figure 3. Baseline Demographics by Race

Pie chart summarizing how many White, Black or African American, Asian, American Indian or Alaska Native, and other patients were in the clinical trial. In total, 1496 (71%) White patients, 89 (4%) Black or African American patients, 314 (15%) Asian patients, 191 (9%) American Indian or Alaska Native patients, and 23 (1%) other patients participated in the clinical trial.

Source: Adapted from FDA Review

Figure 4 summarizes the percentage of patients by ethnicity enrolled in the clinical trial used to evaluate the efficacy of PAXLOVID.

Figure 4. Baseline Demographics by Ethnicity

 Pie chart summarizing how many Hispanic, not Hispanic, and not reported patients were in the clinical trial. In total, 872 (41%) Hispanic or Latino patients, 1229 (58%) not Hispanic or Latino patients, and 12 (1%) not reported patients participated in the clinical trial.

Source: Adapted from FDA Review

What are the benefits of this drug?

In one trial in unvaccinated patients with mild to moderate COVID-19 who were at high risk for progression to severe COVID-19, the rates of death and COVID-19 related hospitalizations were significantly lower in patients who received PAXLOVID than in patients who received placebo.

Were there any differences in how well the drug worked in clinical trials among sex, race, and age?

  • Sex: PAXLOVID worked similarly in males and females.
  • Race: PAXLOVID worked similarly in all evaluated race groups. However, most of the patients were White and data on Black or African American patients were limited.
  • Age: Patients older than 60 years of age are at higher risk of severe outcomes from COVID-19. A higher reduction in percentage of COVID-19 related hospitalization or death from any cause through Day 28 was observed in patients treated with PAXLOVID older than 60 years of age compared to those younger than 60 years of age.

What are the possible side effects?

PAXLOVID can interact with other medicines causing severe or life-threatening side effects or death. It is very important to tell your healthcare provider about all the medicines you take, including prescription and over-the-counter medicines, vitamins, and herbal supplements, because additional laboratory tests or changes in the dose of your other medicines may be necessary during treatment with PAXLOVID. Your healthcare provider may also tell you about specific symptoms to watch out for that may indicate that you need to stop or decrease the dose of some of your other medicines.

The most common side effects of taking PAXLOVID include impaired sense of taste (for example, a metallic taste in the mouth) and diarrhea.

Were there any differences in side effects among sex, race, and age?

  • Sex: The occurrence of side effects was similar in males and females.
  • Race: The occurrence of side effects was similar among all race groups. However, most of the patients were White and data for other racial groups were limited.
  • Age: The occurrence of side effects was similar in patients younger and older than 65 years of age.

GLOSSARY

CLINICAL TRIAL: Voluntary research studies conducted in people and designed to answer specific questions about the safety or effectiveness of drugs, vaccines, other therapies, or new ways of using existing treatments.
COMPARATOR: A previously available treatment or placebo used in clinical trials that is compared to the actual drug being tested.
EFFICACY: How well the drug achieves the desired response when it is taken as described in a controlled clinical setting, such as during a clinical trial.
PLACEBO: An inactive substance or “sugar pill” that looks the same as, and is given the same way as, an active drug or treatment being tested. The effects of the active drug or treatment are compared to the effects of the placebo.
SUBGROUP: A subset of the population studied in a clinical trial. Demographic subsets include sex, race, and age groups.

LINK TO DRUG PACKAGE INSERT:

PAXLOVID

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