The U.S. Food and Drug Administration on Wednesday approved the emergency use of Pfizer's new antiviral pill Paxlovid in people who are at high risk for severe COVID-19. It's the first approved treatment for COVID-19 meant to be taken at home.
"Today's authorization introduces the first treatment for COVID-19 that is in the form of a pill that is taken orally -- a major step forward in the fight against this global pandemic," Dr. Patrizia Cavazzoni, director of the FDA's Center for Drug Evaluation and Research, said in an agency news release. "This authorization provides a new tool to combat COVID-19 at a crucial time in the pandemic as new variants emerge."
Pfizer first asked for emergency authorization in mid-November, and later announced stunning final trial results on the power of Paxlovid to guard against severe COVID-19. In that trial, the pill, taken for five days, slashed a person's odds for hospitalization and death by nearly 90% in high-risk people. Paxlovid should be taken within three to five days of symptom onset, the FDA said.
"Today's authorization of Paxlovid represents another tremendous example of how science will help us ultimately defeat this pandemic, which, even two years in, continues to disrupt and devastate lives across the world," Pfizer Chairman and CEO Albert Bourla said in a company statement. "This breakthrough therapy, which has been shown to significantly reduce hospitalizations and deaths and can be taken at home, will change the way we treat COVID-19, and hopefully help reduce some of the significant pressures facing our health care and hospital systems."
One infectious diseases expert welcomed the news.
"Paxlovid's approval is a major milestone that marks another step towards making COVID-19 a much more manageable infection," said Dr. Amesh Adalja, a senior scholar at the Johns Hopkins Center for Health Security, in Baltimore. "An oral pill that can cut hospitalizations and deaths by 90% is pathbreaking. There are two key issues, however, that remain: it will be scarce in the coming weeks, and its optimal use requires prompt diagnosis, which can be difficult with the continual testing problems that plague us."
At the time of the trial results, Bourla stressed the importance of adding another weapon to the COVID-fighting arsenal.
"This news provides further corroboration that our oral antiviral candidate, if authorized or approved, could have a meaningful impact on the lives of many, as the data further support the efficacy of Paxlovid in reducing hospitalization and death, and show a substantial decrease in viral load. This underscores the treatment candidate's potential to save the lives of patients around the world," Bourla said in a company statement released Dec. 14 with the trial results. "Emerging variants of concern, like Omicron, have exacerbated the need for accessible treatment options for those who contract the virus, and we are confident that, if authorized or approved, this potential treatment could be a critical tool to help quell the pandemic."
Pfizer also delivered some good news about people who are at low risk for severe COVID-19 at that point: In an early analysis, a second, ongoing study that tested whether Paxlovid eased COVID-19 symptoms faster in people who are not considered high-risk found no benefit for symptom relief. But those who took the pill regimen saw the amount of virus in their bodies plummet, and the pill reduced the already low risk for hospitalization and death. That study included those who were vaccinated and had at least one risk factor for severe COVID-19.
Paxlovid is a combination of a new molecule developed specifically to disable SARS-CoV-2 and ritonavir, an HIV medication that helps slow the breakdown of the coronavirus-specific molecule.
The drug does have some limitations. Ritonavir can interact with many commonly taken medicines, and those risks may need to be managed by physicians and pharmacists, the FDA said.
Possible side effects of Paxlovid include impaired sense of taste, diarrhea, high blood pressure and muscle aches, the FDA said. Using Paxlovid in people with uncontrolled or undiagnosed HIV infection may trigger HIV-1 drug resistance. Ritonavir can cause liver damage, so caution should be used when giving Paxlovid to patients with liver conditions, the agency added.
Paxlovid is also not recommended in patients with severe kidney impairment. In patients with moderate kidney impairment, a reduced Paxlovid dose is needed, the FDA said.
Visit the U.S. Centers for Disease Control and Prevention for more on COVID treatments.
SOURCES: U.S. Food and Drug Administration, news release, Dec. 22, 2021; Pfizer, statements, Dec. 14, 2021 and Dec. 22, 2021; Amesh Adalja, MD, senior scholar, Johns Hopkins Center for Health Security, Baltimore