CAMBRIDGE, Mass. (WPRI) — The COVID-19 vaccine rollout continues as additional strains of the virus emerge, some of which may be deadlier than others.
Cambridge-based biotechnology company Moderna, Inc., said Monday its two-dose regimen is expected to protect against all of the strains detected to date.
The U.S. Centers for Disease Control and Prevention (CDC) says multiple SARS-CoV-2 variants are circulating globally, the most notable emerging from the United Kingdom, South Africa and Brazil.
A number of states have reported cases of the U.K. variant. Patrick Vallance, the British government’s chief scientific adviser, said “there is evidence that there is an increased risk for those who have the new variant.”
Vallance stressed to reporters, however, that “the evidence is not yet strong” and more research is needed.
Moderna announced Monday that “out of an abundance of caution,” it has launched a clinical program to boost immunity to emerging COVID-19 variants.
The company said it would test an additional “booster dose” of its COVID-19 vaccine to “study the ability to further increase neutralizing titers against emerging strains beyond the existing primary vaccination series.”
The company is also advancing a booster candidate against the variant first detected in the Republic of South Africa, known as B.1.351, into preclinical studies, as well as a Phase 1 study in the United States. Moderna said the study would allow scientists to “evaluate the immunological benefit of boosting with strain-specific spike proteins.”
Moderna says it expects its mRNA-based booster vaccine will be able to “further boost neutralizing titers in combination with all of the leading vaccine candidates.”
Dr. Tal Zaks, Moderna’s chief medical officer, told The New York Times the company is developing a new form of its vaccine as “an insurance policy.”
“I don’t know if we need it, and I hope we don’t,” Zaks said.
On CBS Face the Nation Sunday, former FDA commissioner Dr. Scott Gottlieb said he is “fairly confident” a new strain of the virus from Brazil is already in the U.S. and “we’re just not detecting it yet.”
However, Gottlieb suggested the ongoing vaccine rollout could help prevent new strains from becoming more widespread in some parts of the country.
“As the weather warms, as we get more people vaccinated, as more people develop immunity from prior infection from the wild type strains of strains that are circulating right now, these new variants won’t gain enough of a foothold to really create a resurgence or new epidemics,” he explained.
“But, in parts of the country where it might already be 1% or 2% of infections — and that may be parts of Florida and San Diego — they do face the risk of outbreaks with these new variants because it’s reached a threshold where it may grow quickly enough that our vaccines and our warming where there won’t be enough of a backstop to keep these at bay,” Gottlieb continued.
Also joining Face the Nation Sunday, the country’s top infectious disease expert, Dr. Anthony Fauci, said the South African strain is more concerning than the U.K. variant already in the United States.
“Particularly its negative impact on some of the monoclonal antibodies that have been given for treatment, that it can, in some respects, knocks out their efficacy,” Fauci said.
“It looks like it does diminish more so the efficacy of the vaccine, but we’re still within that cushion level of the vaccines being efficacious against these mutants,” he added.
Fauci, whose own National Institutes of Health helped to develop the Moderna vaccine, said down the line, “we many need to modify and upgrade the vaccines,” but added that the best way to protect against further evolution of the virus is to vaccinate as many people as possible with the vaccines available.