A nurse prepares a syringe containing a dose of the Modern Coronavirus (COVID-19) vaccine at the Enfermera Isabel Zendal Hospital in Madrid, Spain on July 23, 2021.
Juan Medina | Reuters
Moderna CEO Stéphane Bansel said Thursday that the effectiveness of boosters against Covid-19 is likely to decline over time, and people may need a fourth injection in the fall to boost their protection.
Bansel said people who received the boosters last fall are likely to have enough protection to withstand the winter when new infections emerge, when people gather indoors to escape the cold.
However, Bansel said the booster’s effectiveness is likely to decline over the course of several months, as it did with the first two doses. The head of Moderna was interviewed by Goldman Sachs during a healthcare investment bank executives conference.
“I’ll be surprised when we get this data in the coming weeks, which persists well over time — I expected it to not be good,” Bunsel said, referring to the power of the booster shots.
An unprecedented surge in infections caused by the highly contagious variant of the omicron is currently spreading around the world. According to an analysis of data from CNBC at Johns Hopkins University, more than 574,000 new cases are reported every day in the United States on average over seven days.
The CEO of Moderna said governments, including the UK and South Korea, are already ordering upcoming doses. “I still believe we will need boosters in the fall of 22 and beyond,” Bansel said, adding that older people or those with underlying medical conditions may need annual boosters for years to come.
“We said we first believe this virus will not go away,” Bansel said. “We’re going to have to live with this.”
Moderna released preliminary data last month that showed that its currently authorized 50 microgram booster injection increases the amount of antibodies that block omicron infection by 37 times. A 100 microgram booster boosted these antibodies 83-fold.
Booster shots are playing an increasingly important role in public health strategies to combat the virus, as defenses against the two original shots have been severely affected by the omicron.
Data from the United Kingdom showed that the two-dose Moderna and Pfizer vaccines were only about 10% effective in preventing symptomatic omicron infection 20 weeks after the second dose.
The same study published by the UK Health Safety Agency found that booster doses were up to 75% effective in preventing symptomatic infection two weeks after vaccination.
However, according to research, the effectiveness of booster shots begins to decline after about four weeks. The boosters were 55% to 70% effective in preventing infection by weeks five to nine and 40% to 50% at 10 weeks after vaccination.
Pfizer CEO Albert Burla told CNBC last month that people are likely to need a fourth dose and that the shot may be needed earlier than expected due to the virulence of the omicron.
Bancel said in an interview with Goldman Sachs that the omicron could accelerate the transition from an acute crisis caused by the virus to an endemic phase, when enough people have immune defenses so that Covid will not be as damaging to public life.
However, he also cautioned against predictions, noting that the omicron, with its dozens of mutations, took much of the scientific community by surprise. The data so far indicate that omicron is more transmissible but less dangerous than previous strains.
However, an accidental mutation could change the course of the pandemic again, Bansel said.
“That it is completely impossible to predict whether a new mutation will appear in a day, a week or three months, which will be worse in terms of the severity of the disease,” he said. “This is the part we just need to be careful with.”