Why Pfizer And Moderna CEOs Are Recommending Covid-19 Vaccine Boosters, And Why Some Experts Don't Agree Yet

During a recent event, two chief executive officers (CEOs) of American pharmaceutical companies, which developed mRNA Covid-19 vaccines, said that a booster dose can be required as soon as September this year for those who were among the earliest vaccinated.

Both the CEOs of Moderna and Pfizer said during an Axios COVID-19 vaccine event on 19 May that depending on the research being done on the efficacy and longevity of the vaccines against the coronavirus-caused disease, a booster shot could be needed between eight and 12 months after the recipient’s initial two-dose inoculation series.

However, according to Pfizer, which made similar comments earlier also, the decision is mostly dependent on healthcare officials at the Centers for Disease Control and Prevention (CDC) and the Food and Drug Administration (FDA) to approve the booster dose.

The company told FOX TV stations separately that based on the current understanding, “our thinking is that a third dose, a boost of our vaccine, may be needed at some time in the future to extend protection against Covid-19, subject to approval by regulatory authorities."

In early May, Moderna’s president, Dr Stephen Hoge suggested taking booster shots every nine to 12 months to prevent severe illness from Covid-19 could be a possibility.

"That probably looks like boosting on a nine to 12 month after primary series as an annual booster for now, at least while we’re continuing to see the evolution of the virus," he said on 6 May.

However, the CEO of Moderna, Stéphane Bancel told Axios that he would recommend another vaccine dose to be administered starting in September to those people who got the second dose in January this year.

"I think as a country we should rather be two months too early, than two months too late with outbreaks in several places," he said.

Bancel explained that the new SARS-CoV-2 variants continue to emerge around the world, “we believe that over the next six months as the southern hemisphere enters the fall and winter, we could see more variants of concern emerge".

In such a situation, booster shots will be needed said the Moderna CEO and added that “we believe that the virus is not going away".

In the United Kingdom, Nadhim Zahawi, who is the vaccine minister said people who are clinically extremely vulnerable could begin to receive booster shots against new variants as early as September.

In the case of Johnson & Johnson, which developed another vaccine against the Covid-19, it did not reveal whether the company recommends a booster shot or not.

Dr Anthony Fauci, who is the director of the National Institute of Allergy and Infectious Diseases and currently serving as President Joe Biden’s chief medical adviser, told Axion on 19 May that he also believes booster shots will be necessary within a year of the initial vaccination process.

He said: “We know that the vaccine durability of the efficacy lasts at least six months and likely considerably more”.

“But I think we will almost certainly require a booster sometime within a year or so after getting the primary because the durability of protection against coronaviruses is generally not lifelong,” he added.

Earlier this week, Dr Peter Marks, director of the FDA’s Center for Biologics Evaluation and Research said during a virtual press conference that vaccines developed by Moderna, as well as Pfizer and its German partner BioNTech, are highly effective at preventing Covid-19 disease.

It was also found that these vaccines can protect against the SARS-CoV-2 variants which have been circulating in the United States.

“But we still don’t know. It could be more, it could be a little less ... this is just something we’re gonna have to figure out as we go,” the expert added.

But like many experts, Cornell University professor and virologist John Moore also pointed out a different side of such recommendation made by the CEOs.

"It’s not proven that we need boosters yet. Whereas it’s appropriate to plan for boosters, you’ve got to look at whether there’s a corporate agenda behind this," he told Axios.

According to him, “We don’t have any evidence that protective immunity has dropped to a troubling point, and certainly not for people immunized in December, January, February.”

Prof Moore added that it is hard to say “ where we will be in November because right now it’s May”.

Vaccines And Efficacy

According to a study that included 927 people, conducted by Pfizer and published on 1 April, the mRNA vaccine offered 91.3 per cent protection against the coronavirus caused disease, measured from seven days through to six months after the second dose.

The US pharma giant Pfizer is also conducting another study to find out the effectiveness of a third dose of the vaccine — a booster, given six to 12 months after the second jab.

This research is a part of Pfizer’s clinical development strategy to determine the efficacy of a third dose of the same vaccine against emerging variants.

In the case of Moderna, a study, looking at the time period which its vaccine gives to protect against the virus, also showed that those individuals who took two shots had good antibody levels at six months after the second dose.

For another vaccine, developed by the University of Oxford and pharmaceutical company AstraZeneca, currently available data is not enough.

But in the case of the effectiveness of this vaccine, studies have shown that the efficacy reached 82.4 per cent after a second dose for those who had a dosing interval of 12 weeks or more.

It means that if the two doses of the Oxford-AstraZeneca vaccine are given at least three months apart they offer over 82 per cent protection.

So, it is reasonable to think that the vaccine protection will last at least a further three months after the second jab.

As per the World Health Organization, the Johson & Johnson Covid-19 vaccine, Ad26.CoV2.S, has an efficacy of 85.4 per cent against severe disease and hospitalisation which was observed 28 days after vaccination.

The UN agency also noted that a dose of Janssen Ad26.COV2.S was found in clinical trials to have an efficacy of 66.9 per cent against symptomatic moderate and severe novel coronavirus infection.