Stephane Bancel, who joined Moderna in 2011, said on Thursday that people who received their boosters last autumn will probably retain enough protection to make it through winter as more people gather indoors.
The CEO of Moderna has said that people will likely need a fourth shot of the vaccine as efficacy and the level of protection wanes over time.
Speaking at Goldman Sachs’ healthcare CEO conference, Mr Bancel said the efficacy of the initial booster shot is likely to wane after several months, similar to the first two doses.
“I will be surprised when we get that data in the coming weeks that it’s holding nicely over time – I would expect that it’s not going to hold great,” Mr Bancel said regarding the level of protection provided by the booster shots.
The number of Covid-19 infections is on the rise globally as the highly transmissible Omicron variant of the virus now represents more than 95 per cent of cases in the US, according to the Centers for Disease Control and Prevention. According to data collected by The New York Times, the seven-day average of daily new cases rose reached more than 727,000 on 6 January.
Mr Bancel said governments, such as South Korea and the UK, have started ordering fresh doses in preparation for the need to supply further booster shots.
“I still believe we’re going to need boosters in the fall of ’22 and forward,” Mr Bancel said. He added that older people and those with underlying health problems could need annual boosters for years in the future.
“We have been saying that we believe first this virus is not going away,” Mr Bancel said. “We’re going to have to live with it.”
Moderna published preliminary data in December showing that the company’s 50 microgram booster, which is currently authorised for use, expanded the antibodies that work to prevent infection from Omicron 37-fold. A 100 microgram booster raised the number of antibodies 83-fold.
As the protection from the original vaccination series has taken a hit in the face of Omicron, booster shots have now become a vital part of governments’ public health strategy.
A study by the UK Health Security Agency found that two doses of Moderna and Pfizer’s vaccines are only around 10 per cent effective at preventing symptomatic infection when 20 weeks have passed after a person’s second dose. Two weeks after getting a booster shot, the protection against symptomatic infection increases to 75 per cent, according to the study.
But the efficacy of boosters started to wane after about four weeks, the same study said. Between weeks five and nine, boosters were 55 to 70 per cent effective at preventing infection. Ten weeks after the booster shot, that figure stood between 40 and 50 per cent.
Pfizer CEO Albert Bourla told CNBC in December that people will likely need a fourth dose, and that the need may arise sooner than expected because of the highly transmissible nature of Omicron.
Mr Bancel told Goldman Sachs that the spread of Omicron may lead to a phase of the pandemic that is less disruptive to regular life, but he added that people should be wary of predictions as Omicron surprised many scientists.
While Omicron appears to be more virulent but less severe than other strains of the virus, Mr Bancel cautioned that another variant could once again upend people’s lives.
“What is totally impossible to predict, is there a new mutation coming in a day, a week, three months that is worse in terms of severity of disease,” he said. “That’s a piece that we’ll have to just be cautious about.”
