Pfizer-BioNTech has started the test of a 3rd dose of its COVID-19 vaccine. This is focused on a small group of people to start with.
Pfizer-BioNTech is set to begin the test of the COVID-19 third dose today. Studies have already been done on testing blood serum from people who are vaccinated with their first dose against some of the variants that emerged. They discovered that the immune response triggered by the 2 doses is still shows good result on being protective.
In the case of the United Kingdom variant( B.1.1.7), degree of antibodies raised by the vaccine regimen, a very vital immune shield against the virus, were same with amount against the original, the non-mutated virus while the amount of antibodies raised by the original vaccine were quite lesser against the South African variant (B.1.351).Testing against the Brazilian variant (P1) is still on-going at the moment.
Pfizer Chief Scientific Officer, Mikael Dolsten, made it known that they have not heard any reports of breakthrough cases [among vaccinated people] in relation to any of the new variants so far, when referring to chronic infections with the variant viruses among the people vaccinated.
“We’ll always want to be a step above of the virus. This has made us to think about creating data on a 3rd boost. We will give to people involved in our Phase 1-2 study from last summer a boost with another dose of the new vaccine. We are expecting that the antibody levels rises against current variants to fortify the protection.” Mikael Dolsten says, according to TIME
As this can only be proven by clinical trial, Pfizer-BioNTech is planning to vaccinate a number 144 people who enrolled in the companies’ initial phase studies and took their 2nd dose between 6 and 12 months ago.
In a situation where the added dose doesn’t boost the protection in the people, Dolsten disclosed that Pfizer is developing another vaccine basically for the South African variant. The South African variant has, so far, been the only variant showing the most resistance to vaccine-induced immunity.
Developing a new vaccine for the South African variant actually took a short period to complete (6-8weeks), the reason being that the mRNA technology on which the first vaccine was developed only needed the right genetic sequence to develop a new version, Dolsten says.
Pfizer-BioNTech vaccine has recently been authorized in many countries in a 2-dose regimen, with 21 days space, and has also shown it’s about 95% effective in protection against COVID-19 disease, according to studies.
However, as new (and more infectious) genetic variants of the COVID-19 virus keeps emerging,—U.K., South Africa, and Brazil variants discovered so far, questions about how effective the authorized vaccines can still fight the virus have become a thing of more concern.