A new study has suggested that one mRNA vaccine may be more effective than the other when it comes to the highly contagious Delta variant which is currently wreaking havoc in many parts of the world.
The study is, however, yet to be peer-reviewed and comes even as all COVID-19 vaccines being administered in the U.S. have shown to dramatically reduce the risk of coronavirus infection, severe disease, and death.
The research compared the effectiveness of both the Moderna and Pfizer-BioNTech vaccines in the period from January 2021 till July 2022 in patients at the Mayo Clinic.
Comparable data showed the efficacy of Moderna’s vaccine dropped from 86 percent in early 2021 to 76 percent in July, while the Pfizer-BioNTech COVID-19 vaccine efficacy declined from 76 percent to 42 percent over the same period. These vaccines’ efficacy began to decrease when Delta became the dominant coronavirus strain in the U.S.
The Pfizer-BioNTech vaccine is an mRNA-based vaccine and the latest study suggests that it may be more effective than the Moderna one in terms of protection against Delta.
The study was conducted on more than 50,000 patients in the Mayo Clinic Health System, reports said.
The research paper suggested that a Moderna booster shot may be required for people who were administered any mRNA vaccine earlier this year, according to a Reuters report. Pfizer said a third dose of vaccine may be needed within 6 to 12 months after full vaccination.
Recently, a study published in the New England Journal of Medicine found that two doses of the Pfizer vaccine provide 88 percent protection against Delta. The findings matched earlier data from the Public Health England in May that reported the same level of protection.
In clinical trials, Pfizer’s vaccine is seen to be 95 percent effective in preventing symptomatic COVID-19 and Moderna’s was 94 percent effective.
Meanwhile, another study, also yet to be peer-reviewed, showed that stronger immune responses among elderly nursing home residents in Ontario were seen with the Moderna vaccine compared to that of Pfizer – specifically with respect to the variants of concern.