With the news that Moderna's and Pfizer-BioNTech's Covid vaccines may not be as effective on the new coronavirus variant that emerged in South Africa, it's time to "prepare, if it's necessary, to upgrade the vaccines," Dr. Anthony Fauci said during an interview with NBC News' TODAY Show Monday.
The good news is, both vaccines use innovative messenger RNA, or mRNA technology, and that means researchers have the ability to change and tweak the vaccines to adapt to new variants more easily than with conventional vaccines. Here's how that works.
Both Moderna and Pfizer's Covid vaccines apply innovative technology that utilizes messenger RNA, or mRNA. Messenger RNA is similar to DNA in that it is genetic material that contains instructions; in particular, mRNA gives our cells instructions for making proteins.
Specially sequenced mRNA in these vaccines teaches the body's cells how to make a non-infectious piece of SARS-CoV-2 (the virus that causes Covid), specifically a piece of its famous "spike" protein. The immune system then recognizes the harmless copies of the spike protein and creates antibodies against it. If exposed to the actual virus, the body recalls how to trigger an immune response and create antibodies that fight the virus.
This new form of vaccine is exciting because mRNA vaccines can be modified easily and manufactured faster and with less material than conventional vaccines.
Dr. Kizzmekia Corbett, who led the team responsible for Moderna's vaccine, has referred to mRNA vaccines as a "plug and play" approach: It's possible to replace one sequence of mRNA in the vaccine for another in a matter of weeks.
This allows drug companies to jump into action creating and testing vaccines that mimic new coronavirus variants that arise.
Though preliminary data suggests the current vaccines can have a neutralizing effect on the U.K. variant that has emerged (it takes "multiple mutations in the spike protein" for a virus variant evade immunity from vaccines, according to the CDC), the South African variant is murkier. So "out of an abundance of caution," Moderna is currently working on a vaccine booster for the South African strain (and possibly others), Dr. Stephen Hoge, president of Moderna, told Time.
Making the booster is essentially a matter of "copying and pasting" in the South African mutation, he said.
And that process is "not something that is a very onerous," Fauci said during a White House press briefing Friday. "That's something we can do that given the platforms we have."
Indeed, Moderna's booster will use the same technology, chemistry and manufacturing process as the initial vaccine, Moderna CEO Stephane Bancel told CNBC's "Squawk Box" Monday. "So, the products are very similar with just a few mutation changes...." (The vaccine will also need to be tested for safety and efficacy and approved by the FDA.)
Bancel said that if the South African strain becomes an issue in the fall, the booster would be ready to distribute by then.
But ultimately, said Fauci, if the vaccines are less effective on the emerging variants, it's "all the more reason why we should be vaccinating as many people as you possibly can."