FDA advisors recommend full approval of Pfizer’s Covid treatment Paxlovid for adults 50 and older and other high-risk individuals

The Food and Drug Administration’s independent advisory panel on Thursday recommended full approval of Pfizer’s Covid-19 antiviral pill Paxlovid for high-risk 16-1 adults, but pointed to potentially harmful drug interactions.

Treatment is recommended for people over 50 years of age or people suffering from a variety of medical conditions like high blood pressure or diabetes, which put them at a higher risk of ending up in hospital or dying from Covid.

The FDA first made Paxlovid available for use in December 2021 emergency response in risk persons aged 12 and over. Pfizer made an application for full approval of the drug in June 2022, but the FDA expanded its review Deadline for application in December 2022.

The agency generally follows the advice of its advisory committees, but is not obliged to do so. A final decision will be made in May.

“I would say that along with oxygen, Paxlovid has probably been and continues to be the most important treatment tool during this epidemic,” said Richard Murphy, chief of infectious diseases at Veterans Affairs White River Junction Medical Center.

The panel relied on three of Pfizer’s mid- to late-stage clinical trials of Paxlovid, which enrolled more than 6,000 patients in 21 countries.

A study called EPIC-HR looked at high-risk adults who were unvaccinated and had no prior Covid infection. The study found that Paxlovid reduced the risk of hospitalization or death by 86% in adults treated within five days of symptom onset and by 89% in those treated within three days of symptom onset, such a review of the company’s data by the FDA.

“I found the efficacy data clear and compelling,” said Dr. Sankar Swaminathan, chief of the Department of Infectious Diseases at the University of Utah School of Medicine.

However, the advisors agreed that serious side effects due to drug-drug interactions or DDIs are an important safety issue with Paxlovid.

“I just want to emphasize that we underscore the importance of risk reduction for the prescriber, primary care provider, physician and other prescribers in relation to drug-drug interactions,” said Dr. David Hardy, associate clinical professor of medicine at the University of Southern California. “That’s where I think we could get in trouble, I should say where they would get in trouble if they prescribe this drug without knowing well what ritonavir does to other drugs,” he said. Paxlovid consists of two antiviral drugs, ritonavir and nirmatrelvir.

More than half of Paxlovid-eligible Medicare and Veterans Affairs patients take medications that have drug-drug interactions with Paxlovid, according to an FDA review of safety surveillance data. About 74% of Paxlovid prescriptions came from adult primary care physicians who may not have experience managing possible adverse drug interactions, the FDA review added.

The FDA said its Office of Surveillance and Epidemiology had recorded 271 reports of serious adverse events potentially related to drug-drug interactions with Paxlovid through the end of January, including 147 hospitalizations. The most common drugs causing problems are immunosuppressants, which are commonly used to treat HIV and organ transplant patients, according to the FDA.

Paxlovid consists of two separate medicines packaged together and is designed to reduce the risk of hospitalization or death from Covid. Nirmatrelvir blocks a key enzyme the Covid virus needs to replicate, while ritonavir boosts the first drug’s ability to fight infection.

Patients take Paxlovid within five days of experiencing Covid symptoms to reduce the risk of hospitalization or death. To complete a full cycle of the drug, patients must take three Paxlovid pills twice a day for five days.

More than 12 million packs of Paxlovid have been shipped to US pharmacies and retail pharmacies 1.3 million doses are available nationwide acc federal data. About 10 million patients in the US and 14 million worldwide have been treated with the drug, according to Jim Rusnak, Pfizer’s chief development officer for internal medicine.

Paxlovid’s sales rose to $18.9 billion in 2022, the first year it was available, but Pfizer expects sales to fall 58% this year to $8 billion.