UCLA’s study does not find a significant benefit of Paxlovid for vaccinated older adults

Paxlovid does not significantly reduce the hospitalization and mortality of COVID-19 between vaccinated elderly adults, according to a new research under the leadership of UCLA.

The study challenges the assumption that Paxlovid’s effectiveness in reducing COVID-19 hospitalizations and deaths in non-vaccinated adults also applies to vaccinated adults. Pfizer’s 2022 clinical trial found reduced COVID-19 hospitalization in non -vaccinated middle -aged adults; while a later clinical trial 2024 did not find a significant reduction vaccinated Average age adults. Since most elderly Americans have already received two or more Covid-19 vaccines, Paxlovid’s efficiency in vaccinated elderly adults has remained an important unanswered question.

“Since the strongest predictor of the serious Covid-19 is Advanced Age, it was vital to prove to be evidence of whether the results of Pfizer tests are generalized in elderly and vaccinated populations,” said Dr. John Mafi, an associate professor at Residence of Medicine at the Directorate of Internal Medicine and Health Services at David Medical School Geffen in UCLA and the main author of the study.

“Our study effectively excludes the idea that Paxlovid causes large reductions in COVID-19 hospitalization in vaccinated elderly adults,” MAFI said. “While we cannot exclude a slight reduction in Covid-19 hospitalization, our results show that at best, Paxlovid’s possible effect on Covid-19 hospital of Pfizer 2022.

Findings, which will be published in assessment by peer Price“It is important because the clinical trial of Pfizer 2022 continues to serve as the foundation of evidence that supports Paxlovid’s perceived efficiency, the list of about $ 1,650 per healing course and the widespread global use,” MAFI said.

Since the study did not find a significant effect on COVID-19 hospitalizations and deaths between vaccinated elderly adults, our findings highlight the urgent need for further randomized clinical trials investigating Paxlovid’s effects on higher risk populations such as weak or immunosuppressed. ”

Dr. Katherine Kahn, a distinguished professor of medicine in the Department of General Internal Medicine and the Senior Author of the Study

In order to determine the association between Paxlovid and Covid-19 hospitalization, the hospitalization of all causes and mortality results of all the causes, the researchers took advantage of a natural experiment in Ontario, Canada. Between April 1st and November 30th, 2022, Ontario applied a limited age policy on access to Paxlovid that undertook it for coincidental adults for Covid-19s aged 70 or older unless they were immunosuppressed or had other risk factors . The researchers used data from several Ontario health databases associated with Ices, the main manager of Ontario’s health data.

The results of patients who were just below just 70 years old were compared, who were reasonably similar except for their exposure to Paxlovid. Researchers found that among the 1.6 million very vaccinated elderly, the Paxlovid restriction policy for people aged 70 increased the percentage of Paxlovid recipes by 118% at the age of 70. -19 hospitalization associated with hospitalization, hospitalization for all causes or mortality effects of all causes.

By restricting Paxlovid by age, policy has created a rare natural experiment analyzed by the study to evaluate Paxlovid’s impact on the basic effects of health, effectively avoiding joint observational research known as unbeaten confusion. “Unpaid confusion is a problem, because the decision to use Paxlovid is not accidental and the factors affecting its use is able to influence the risk of hospitalization or mortality,” said co-author of the study Sitaram Vangala, Biostatistisian at the study Department of Medical Statistical Core.

“Because access to Paxlovid in this study was actually randomized for those close to the age of 70, our results are unlikely to reflect uninhabited confusion,” Vangala said. “This can explain why our results are in line with the recent negative clinical trial of 2024 between vaccinated adults, but not to observation studies showing that Paxlovid is associated with large reductions in hospitalization and mortality in vaccinated adults.”

The study is limited by the lack of individual data at patient level on symptoms, the timetable of previous COVID-19 vaccinations, the receipt of Paxlovid and the adhesion of drugs.

Additional co-authors Many Cui and Artem Romanov of UCLA and Dr. Moira Kapral and Dr. Peter Wu of the University of Toronto. Dr. Wu is connected to Ices.

The study was funded by the Commonwealth Fund and the National Institute for emerging Beeson leaders at the Career Development Award (K76AG064392-01A1). This study was also supported by Ices, which is backed by an annual grant by the Ministry of Health of Ontario (MOH) and the Ministry of Long Care (MLTC).