May 26, 2023 – Today, the U.S. Food and Drug Administration approved the oral antiviral Paxlovid (nirmatrelvir tablets and ritonavir tablets, co-packaged for oral use) for the treatment of mild-to-moderate COVID-19 in adults who are at high risk for progression to severe COVID-19, including hospitalization or death. Paxlovid is the fourth drug—and first oral antiviral pill—approved by the FDA to treat COVID-19 in adults.
Paxlovid manufactured and packaged under the emergency use authorization (EUA) and distributed by the U.S. Department of Health and Human Services will continue to be available to ensure continued access for adults, as well as treatment of eligible children ages 12-18 who are not covered by today’s approval. Paxlovid is not approved or authorized for use as a pre-exposure or post-exposure prophylaxis for prevention of COVID-19.
“While the pandemic has been challenging for all of us, we have made great progress mitigating the impact of COVID-19 on our lives,” said Patrizia Cavazzoni, M.D., director for the FDA’s Center for Drug Evaluation and Research. “Today’s approval demonstrates that Paxlovid has met the agency’s rigorous standards for safety and effectiveness, and that it remains an important treatment option for people at high risk for progression to severe COVID-19, including those with prior immunity. The FDA remains committed to working with sponsors to facilitate the development of new prevention and treatment options for COVID-19.”
Under the Federal Food, Drug, and Cosmetic Act, approval of a new drug requires, among other things, substantial evidence of effectiveness and a demonstration of safety for the drug’s intended use(s). In considering approval of a drug, the FDA conducts a benefit-risk assessment based on rigorous scientific standards to ensure that the product’s benefits outweigh its risks for the intended population.
The efficacy of Paxlovid was primarily supported by the final results of the EPIC-HR clinical trial. 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. Paxlovid significantly reduced the proportion of people with COVID-19 related hospitalization or death from any cause through 28 days of follow-up by 86% compared to placebo among patients treated within five days of symptom onset and who did not receive COVID-19 therapeutic monoclonal antibody treatment. In this analysis, 977 patients received Paxlovid, and 989 patients received placebo, and among these patients, 0.9% who received Paxlovid were hospitalized due to COVID-19 or died from any cause during 28 days of follow-up compared to 6.5% of the patients who received the placebo.
Benefit of Paxlovid was observed in patients with prior immunity to the virus that causes COVID-19. Among patients in EPIC-HR who were antibody positive at trial enrollment, the risk of COVID-19-related hospitalization or death from any cause during 28 days of follow-up was 0.2% among the 490 patients treated with Paxlovid compared with 1.7% of the 479 patients receiving placebo. EPIC-SR was another clinical trial that enrolled vaccinated patients with at least one risk factor for progression to severe COVID-19. Although not statistically significant, among these vaccinated patients, there was a reduction in the risk of COVID-19 related hospitalization or death from any cause.
EPIC-HR and EPIC-SR were randomized controlled trials and provide information about COVID-19 rebound. Data from these two trials showed that rebound in SARS-CoV-2 (RNA or virus) shedding or COVID-19 symptoms occurred in a subset of patients and happened in both the patients receiving Paxlovid and the placebo. Based on the data currently available to the FDA, there is not a clear association between Paxlovid treatment and COVID-19 rebound.
Because of the importance of reducing the risk of significant drug-drug interactions with Paxlovid, the approved label and authorized Fact Sheet for Health Care Providers for the Paxlovid EUA come with a boxed warning with instructions for prescribers. Prescribers should review all medications taken by the patient to assess for potential drug-drug interactions and determine if other medicines that a patient may be taking require a dose adjustment, interruption and/or additional monitoring. Prescribers should consider the benefit of Paxlovid treatment in reducing hospitalization and death, and whether the risk of potential drug-drug interactions for an individual patient can be appropriately managed.
In conjunction with today’s approval, the FDA is providing all prescribers with important information for prescribing Paxlovid properly and safely, such as dosing instructions, potential side effects and information regarding drugs that may cause drug-drug interactions with Paxlovid. The most common side effects of taking Paxlovid include impaired sense of taste and diarrhea. Patients should discuss with their health care provider whether Paxlovid is right for them.
