Though vaccines have been proven to be effective in protecting against COVID-19, concerns surrounding the waning efficacy of Moderna and Pfizer jabs have been growing. During clinical trials both vaccine companies showed to be effective in shielding people by 90% but one study has found that Moderna produces twice as many antibodies as the Pfizer vaccine.
Twice as many antibodies
Researchers from East Limburg Hospital in Belgium have conducted a study comparing the antibody levels produced by both vaccines by analyzing 1,600 hospital workers. What they found was that those who received the Moderna vaccine produced 3,600 antibody units per milliliter compared to only 1,400 for Pfizer recipients.
While the reason behind this disparity remains uncertain to researchers, they have suggested that it may be due to the longer wait time between doses. For Moderna recipients, four weeks in between both shots is required whereas there is only a three week wait period in between both Pfizer doses. In addition, the Moderna vaccine has a higher concentration of COVID mRNA which, according to researchers, could lead to a greater amount of antibodies developed.
Is there a direct correlation?
But although this might point to Moderna providing better protection than Pfizer, outside scientists have said that a greater amount of antibodies is not necessarily conducive to higher levels of protection. David Benkeser, biostatistician at Emory University, said:
I would urge caution in making the conclusion that because Moderna demonstrated a slightly higher peak on average that its efficacy will be slower to wane. Such a conclusion requires a host of assumptions that have not yet been evaluated.
However, lead author of the study and microbiologist at East Limburg Hospital, Deborah Steensels explained:
Still, it's possible that higher initial antibody levels might correlate with longer duration of protection against mild breakthrough infections.
Also, if higher antibody levels are confirmed to be important, then the Moderna vaccine might be better for immunocompromised people who don't respond well to vaccines.