FDA advisors recommend full approval of Pfizer’s covid treatment Paxlovid for adults age 50 and older and other high-risk individuals.
Paxlovid, a treatment pill for the coronavirus disease (COVID-19), is seen in boxes at Misericordia Hospital in Grosseto, Italy on February 8, 2022.
Jennifer Lorenzini | Reuters
An independent panel of advisers to the Food and Drug Administration recommended full approval for Pfizer COVID-19 Paxlovid, an antiviral pill for high-risk adults, on Thursday marked a potentially harmful drug interaction.
Treatment is recommended for people over 50 years of age or those who are suffering from this disease. Medical condition such as high blood pressure or diabetes that put them at greater risk of ending up in hospital or dying from Covid.
The FDA first made Paxlovid available in December 2021 Emergency use In high-risk individuals aged 12 years and older. Pfizer Application submitted For full drug approval in June 2022, but the FDA Expanded its review Application period in December
The agency generally follows the advice of its advisory committees but is not required to do so. The final decision is due in May.
“I would say, other than oxygen, Paxlovid has probably been and continues to be the single most important treatment tool during this epidemic,” said Richard Murphy, chief of infectious diseases at the Veterans Affairs White River Junction Medical Center.
The panel, which voted 16-1 to recommend full approval, pointed to Pfizer’s three mid-to-late-term clinical trials on paxelwood that enrolled more than 6,000 patients in 21 countries.
A ‘clinically meaningful’ reduction in risk
One trial, called EPIC-HR, looked at high-risk adults who had not been vaccinated and had no prior Covid infection. According to an FDA review of the company’s data, the trial found that Paxlovid reduced the risk of hospitalization or death by 86 percent in adults treated within five days of the onset of symptoms, and 89% reduction in those treated within three days of onset.
“I thought the efficacy data were clear and convincing,” said Dr. Shankar Swaminathan, M.D., chief of the division of infectious diseases at the University of Utah School of Medicine.
Dr. Adora Ademora, a professor of infectious diseases at the University of North Carolina School of Medicine, called the reduction in risk in Pfizer’s trials “clinically meaningful” for most individuals and the broader population, at a time when the U.S. is still Sees thousands of people. Covid cases every week. According to , around 200,000 Covid cases are reported weekly across the country. Centers for Disease Control and Prevention.
But the consultants agreed that serious adverse reactions due to interactions between Paxlovid and other drugs are a major safety concern.
This photo taken on July 31, 2022 shows a health worker taking a swab sample from a woman who tested positive for the Covid-19 coronavirus at a swab collection site in Guangzhou, south China’s Guangdong Province. Being tested for the virus. According to a study posted online Tuesday, about a third of people with Covid will experience a recovery of their symptoms, regardless of whether they are treated with the antiviral Paxlovid.
Str AFP | Getty Images
“I would just emphasize that we highlight the importance of risk reduction for prescribers, primary care, physicians and other prescribers in terms of drug interactions,” said Dr. David Hardy, University of Medicine’s Dr. An adjunct clinical professor of Southern California.
“That’s where I think we can get into trouble, I should say, where they’re going to get into trouble prescribing this drug without a good knowledge of what ritnavir is. [one of the medications in Paxlovid] It does with other drugs,” he said.
According to an FDA review of safety surveillance data, more than half of paxlovid-eligible Medicare and Veterans Affairs patients are on medications that have drug interactions with paxlovid. The FDA review added that about 74% of Paxlovid prescriptions were to adult primary care practitioners who likely lacked experience managing the drug’s potential adverse interactions.
The FDA said its Office of Surveillance and Epidemiology recorded 271 reports of serious adverse events possibly related to drug interactions with Paxlovid, including 147 hospitalizations and six deaths through the end of January. Included. The most common drugs that caused problems were immunosuppressants, often used to treat HIV and organ transplant patients, the FDA said.
But Swaminathan noted that drug interactions should be “detected and minimized.” FDA staff said earlier in the meeting that the conversation could potentially improve drug safety for prescribers and patients by adjusting dosages of certain drugs, increasing patient monitoring and ensuring product labeling. Interactions can be reported.
Paxlovid consists of two drugs: normatrivir, which blocks a key enzyme that the Covid-19 virus needs to replicate, and ritonavir, which increases the ability of the first drug to fight the infection.
Patients take Paxlovid within five days of the onset of Covid symptoms to reduce their risk of hospitalization or death. To complete a full course of medication, patients should take three Paxlovid tablets twice a day for five days.
More than 12 million courses of Paxlovid have been delivered to pharmacies across the United States. 1.3 million doses are available. Nationwide, according to Federal data. About 10 million patients in the U.S. and 14 million worldwide have been treated with the drug, according to Jim Rusnak, chief development officer for internal medicine at Pfizer.
Sales of Paxlovid 18.9 billion dollars in 2022.the first year it was available, but Pfizer expects revenue to fall 58% to $8 billion in 2023.
The lone vote against Paxlovid was from Patient Representative Terry Gillespie of Plainfield, Illinois. Gillespie expressed concern about doctors not knowing when to prescribe the drug, noting that he had four to five Covid infections “but not once” was offered Paxlovid.
“I don’t think doctors really know how to use it,” Gillespie said.
After the vote, Swaminathan said he had a “disturbingly large number of patients” whose doctors had discouraged them from taking Paxlovid because of fears of a resurgence of Covid cases. This happens when patients see a return of their Covid symptoms or test positive after initially recovering.
“I am concerned that the medical community lacks common sense and prevents patients from receiving an effective drug that could save their lives,” he said.
Reports of these cases surfaced after Paxlovid entered the market in 2021. Joe Biden And his former chief medical adviser, Dr Anthony Fauci, apparently recovered from Covid after taking an antiviral cocktail before testing positive again.
Swaminathan said there is a “dramatic acceptance” in the media that Paxlovid causes cases of relapse and that, despite a lack of data to support this belief, it is “more likely than patients before taking the drug.” “Possibly worse.”
Dr. Lindsay Baden, the panel’s chairperson and director of Brigham and Women’s Hospital, added that emerging data suggest that rebound cases due to Paxlovid “are not the biology of what’s going on.”
“Recently, and even today, some of the data that’s been shared has helped me understand what that means. So we’re seeing real-time data that’s structured and informative,” Baden said. are,” Baden said.
An FDA review of Pfizer’s clinical trials found that overall rebound rates ranged from 10% to 16%, with patients who received paxlovid having “symptom rebound or moderation” compared to patients who received placebo. No evidence of a high rate of rebound of choice symptoms”. According to agency staff, this prevailed regardless of patients’ risk of severe disease, or omicron variant or prior strain.
More data are needed in immunocompromised patients.
Before the panel’s vote, FDA staff said more data are needed to determine whether immunocompromised people need a longer course of paxilvid beyond the traditional five days. They cited an overall lack of clinical trial data on Paxlovid use in these people, noting that only 13 of more than 2,000 patients in the EPIC-HR trial had weakened immune systems.
FDA staff said that immunocompromised people may benefit more from longer courses of Paxlovid because they are more likely to have prolonged Covid infection. The Centers for Disease Control and Prevention states that immunocompromised patients can remain contagious up to 20 days after the onset of symptoms, and Recommends Those patients are isolated for at least 20 days. According to the CDC, about 7 million American adults are immunocompromised. Estimation.
Pfizer representatives highlighted the company’s ongoing efforts to research the use of Paxlovid in immunocompromised patients. In September, the company began enrolling patients in a clinical trial evaluating different durations of Paxlovid courses, including 10- and 15-day courses.
Dr. Paula Carvalho, a professor at the University of Washington, said she was “quite satisfied” with the company’s plan, but said she hoped the HIV population would be included in clinical trials.
“I hope the study can be done in time, because we need this information very badly,” Carvalho said.