A study led by the US Centers for Disease Control and Prevention (CDC) found that Moderna vaccine is slightly more effective than Pfizer’s in real-life use.
“Among U.S. adults without immunocompromising conditions, vaccine effectiveness against COVID-19 hospitalization during March 11–August 15, 2021, was higher for the Moderna vaccine (93%) than the Pfizer-BioNTech vaccine (88%) and the Janssen vaccine (71%),” the team wrote in the CDC’s weekly report on death and disease, the MMWR.
“Although these real-world data suggest some variation in levels of protection by vaccine, all FDA-approved or authorized COVID-19 vaccines provide substantial protection against COVID-19 hospitalization.”
CDC found that the biggest difference between the vaccine made by Moderna and Pfizer/BioNtech’s vaccine was driven by a decline that started about four months after people were fully vaccinated with Pfizer’s vaccine.
“Differences in vaccine effectiveness between the Moderna and Pfizer-BioNTech vaccine might be due to higher mRNA content in the Moderna vaccine, differences in timing between doses (3 weeks for Pfizer-BioNTech versus 4 weeks for Moderna), or possible differences between groups that received each vaccine that were not accounted for in the analysis,” the team wrote.
On Friday the Food and Drug Administration vaccine advisory committee will be holding a meeting with outside experts to discuss whether there is enough data to support widely distributing booster shots across the U.S.
Delta is “just so good at infecting people and replicating that it raises the bar on how good vaccines have to be,” said Moderna President Stephen Hoge in a phone interview with CNBC. “It’s actually shown some of the weaknesses that [vaccines] have earlier than you might expect.”