Pfizer scientists are studying whether a THIRD vaccine shot can offer protection against more contagious and resistant COVID strains like the one from South Africa
- Pfizer Inc and its German partner BioNTech are studying a third dose of their coronavirus vaccine
- The booster shot is aimed at protecting against variants, which are better at evading antibodies from vaccine than earlier strains of the virus
- About 144 volunteers will be given the third dose, mostly those who participated in the vaccine’s early-stage U.S. testing last year
- Researchers believe if the shot is given six to 12 months after the first two doses, it may help stimulate the immune system enough to ward off a mutated virus
Pfizer Inc announced on Thursday it has begun studying a third dose of its COVID-19 vaccine, part of a strategy to guard against mutated versions of the coronavirus.
Health authorities say first-generation COVID-19 vaccines still protect against variants that are emerging in different parts of the world including the UK and South Africa.
But manufacturers are now starting to prepare in case a more vaccine-resistant mutation comes along.
Pfizer and its German partner, BioNTech SE, said it will offer a third dose to 144 volunteers, drawing from people who participated in the vaccine’s early-stage U.S. testing last year.
It wants to determine if an additional booster shot given six to 12 months after the first two doses would rev up the immune system enough to ward off a mutated virus.
Pfizer Inc and its German partner BioNTech are studying a third dose of their coronavirus vaccine, which is aimed at protecting against variants (file image)
Variants spreading across the U.S. including the one from South Africa (purple dot),are better at evading antibodies from vaccine than earlier strains of the virus
Researchers believe if the shot is given six to 12 months after the first two doses, it may help stimulate the immune system enough to ward off a mutated virus as the U.S. vaccinates about 1.2 million people per day
The vaccine candidate from Pfizer and BioNTech uses part of the pathogen’s genetic code called messenger RNA, or mRNA, to get the body to recognize the coronavirus and attack it if a person becomes infected.
In the jab, known as BNT162b2, the mRNA encodes for all of the spike protein found on the outside of the virus that it uses to enter and infect cells.
‘While we have not seen any evidence that the circulating variants result in a loss of protection provided by our vaccine, we are taking multiple steps to act decisively and be ready in case a strain becomes resistant to the protection afforded by the vaccine,’ Pfizer CEO Albert Bourla said in a statement.
‘At the same time, we are making the right investments and engaging in the appropriate conversations with regulators to help position us to potentially develop and seek authorization for an updated mRNA vaccine or booster if needed.’
Recently, in a study punished in the New England Journal of Medicine, Pfizer teamed up with the University of Texas Medical Branch to test its vaccine against the South African variant, known as B.1.351.
They found that only one-third of its neutralizing antibodies were activated compared with its effect on the most common version of the virus prevalent in U.S. trials.
However, the pharmaceutical giant said the actual efficacy of its vaccine against the South African variant is yet to be determined.
Pfizer and BioNTech are also are tweaking their vaccine recipe.
The companies are in discussions with U.S. and European regulators about a study to evaluate doses updated to better match variants such as the one first discovered in South Africa.
This is a breaking news story and will be updated.