Exactly when and what is still to be determined, but the companies producing vaccines all seem to agree on the need for boosters. Albert Bourla, Pfizer’s chief executive officer, told CNBC that people will “likely” need a booster dose within 12 months of getting fully vaccinated.
“A likely scenario is that there will be likely a need for a third dose, somewhere between six and 12 months and then from there, there will be annual revaccination, but all of that needs to be confirmed. And again, the variants will play a key role,” he told the business network.
Earlier this year, Johnson & Johnson CEO Alex Gorsky had also said that he thought seasonal shots might be necessary for COVID-19, as with influenza.
Moderna’s CEO, Stéphane Bancel, predicted, meanwhile, that some Americans might be getting a COVID-19 booster shot as early as September. Moderna recently announced initial data from its phase II study showing that a single 50-µg dose of mRNA-1273 or mRNA-1273.351, given as a booster to previously vaccinated individuals, increased neutralizing antibody titer responses against SARS-CoV-2 and two variants of concern, B.1.351 (first identified in South Africa) and P.1 (first identified in Brazil).
A booster dose of mRNA-1273.351, Moderna’s strain-matched booster, achieved higher neutralizing antibody titers against the B.1.351 variant of concern than a booster dose of mRNA-1273.
“As we seek to defeat the ongoing pandemic, we remain committed to being proactive as the virus evolves,” Bancel stated. “We are encouraged by these new data, which reinforce our confidence that our booster strategy should be protective against these newly detected variants. The strong and rapid boost in titers to levels above primary vaccination also clearly demonstrates the ability of mRNA-1273 to induce immune memory.”
He added that the mRNA platform “allows for rapid design of vaccine candidates that incorporate key virus mutations, potentially allowing for faster development of future alternative variant-matched vaccines should they be needed.”
At the same time, the National Institutes of Health has begun a phase I/II clinical trial to determine the safety and immunogenicity of mixed-booster regimens. For the study, adult volunteers who have been fully vaccinated against COVID-19 will receive booster doses of different COVID-19 vaccines.”
“Although the vaccines currently authorized by the U.S. Food and Drug Administration offer strong protection against COVID-19, we need to prepare for the possibility of needing booster shots to counter waning immunity and to keep pace with an evolving virus,” said Anthony S. Fauci, MD, director of the National Institute of Allergy and Infectious Diseases, which is part of NIH. “The results of this trial are intended to inform public health policy decisions on the potential use of mixed vaccine schedules should booster doses be indicated.”
Included in the trial will be about 150 volunteers who already have received one of the three COVID-19 vaccine regimens currently available under FDA emergency-use authorization in the United States: the Janssen COVID-19 vaccine (also referred to as the Johnson & Johnson vaccine, or Ad26.COV2-S), the Moderna COVID-19 vaccine (also known as mRNA-1273), and the Pfizer-BioNTech COVID-19 vaccine (also known as (BNT162b2).
Each vaccine group will enroll about 25 younger adults aged 18 through 55 years, and approximately 25 adults aged 56 years and older. Participants will receive a single booster shot of the Moderna COVID-19 vaccine 12 to 20 weeks following their initial vaccination regimen.
A separate cohort of those who have not yet been vaccinated will receive the two-dose Moderna COVID-19 vaccine regimen and then will be assigned to receive a booster dose of a vaccine about 12 to 20 weeks later.
Trial participants will be followed for 1 year after receiving their last vaccination and will be asked to complete telephone check-ins, show up for various in-person follow-up visits, and provide blood samples. Trial investigators will evaluate participants for safety and any side effects postvaccination while evaluating immune responses against current circulating strains of SARS-CoV-2, as well as emerging variants.
If trial participants develop laboratory-confirmed symptomatic COVID-19, researchers will perform genetic sequence analyses on the participant samples to see if a variant strain of SARS-CoV-2 caused the infection. Initial trial results are expected in late summer 2021.
The content contained in this article is for informational purposes only. The content is not intended to be a substitute for professional advice. Reliance on any information provided in this article is solely at your own risk.