Overview

• A study of 1.6 million older adults in Ontario found no significant reduction in COVID-19 hospitalizations or deaths among vaccinated seniors who took Paxlovid.
• The research highlights that Paxlovid's effectiveness in vaccinated seniors is far lower than previously reported for unvaccinated populations in earlier trials.
• Pfizer's initial clinical trials in 2022 showed an 89% reduction in severe outcomes, but those trials focused on unvaccinated, middle-aged adults, a different demographic from today’s population.
• The study suggests that Paxlovid's ability to prevent hospitalizations in vaccinated seniors is about four times weaker than earlier estimates, requiring 77 prescriptions to prevent one hospitalization.
• Researchers call for further studies to better understand Paxlovid's role in specific high-risk groups, such as frail or immunocompromised individuals.