Britain on Monday became the first country to authorize a coronavirus vaccine that targets two variants, the original virus and Omicron, the variant that became dominant over the winter.
Half of each dose of the Moderna-made vaccine will target the original variant, and the other half will target Omicron. In clinical trials, the vaccine, an updated version of Moderna’s original Covid vaccine, generated a good immune response to these two variants, as well as the BA.4 and BA.5 subvariants in adults, researchers found.
Dr. June Raine, the chief executive of Britain’s Medicines and Healthcare Products Regulatory Agency, said she was pleased that the new booster vaccine met the regulator’s standards of safety, quality and effectiveness. The decision was endorsed by Britain’s independent expert scientific advisory body, the Commission on Human Medicines.
“The first generation of Covid-19 vaccines being used in the U.K. continue to provide important protection against the disease and save lives,” Dr. Raine said. “What this bivalent vaccine gives us is a sharpened tool in our armory to help protect us against this disease as the virus continues to evolve.”
In the United States, the Biden administration expects to begin a Covid-19 booster campaign next month with updated vaccines from Pfizer and Moderna targeting new variants, according to people familiar with the deliberations. Officials decided to delay expanded eligibility for second boosters of existing vaccines this summer because the new formulations were close to being ready. Currently, only Americans over 50 and those over 12 with certain immune deficiencies are eligible for second booster doses.
Read More on the Coronavirus Pandemic
Moderna said in a statement that it was working with British health officials to distribute the new vaccine, but it was unclear when the shots would be available to the public. The company said it had completed regulatory submissions for the vaccine in Australia, Canada, and the European Union and expected further authorization decisions in the coming weeks.
Stéphane Bancel, Moderna’s chief executive, said in a statement on Monday that Britain’s authorization highlighted “the dedication and leadership of the U.K. public health authorities in helping to end the Covid-19 pandemic.” He added that the vaccine had “an important role to play in protecting people in the U.K. from Covid-19 as we enter the winter months.”
The emergence of highly contagious Omicron subvariants this spring appeared to reduce the protection offered by the Pfizer-BioNTech and Moderna vaccines against Covid hospitalizations, with more vaccinated people admitted to the hospital with Covid than they had been during the winter Omicron wave. But booster shots have raised people’s levels of protection, scientists from the U.S. Centers for Disease Control and Prevention said last month. The C.D.C. recommends that people receive booster shots as soon as they are eligible.
Britain has high vaccination rates overall, with 76 percent of the population fully vaccinated and 60 percent having received an additional dose. By comparison, in the United States, 67 percent of the population is fully vaccinated, but the booster program has stalled, with just 32 percent having received an additional dose. Globally, 64 percent of the population is fully vaccinated, according to The New York Times’s Covid vaccine tracker.
Britain accelerated its booster program in December to counter the highly contagious Omicron variant. Currently, anyone 16 years and older is eligible for a booster shot, in addition to some children aged 12 to 15.
Anyone aged 50 and over will be eligible for a further dose in the fall, as well as those 5 years and over who are in a clinical risk group, including pregnant women, the British government said last month. Household contacts of those who are immunocompromised, frontline workers and caregivers will also be eligible. Side effects of the new vaccine were the same as those seen for the original Moderna booster dose and were typically mild, with no serious safety concerns, British regulators said.