Many infectious disease and vaccine development experts told Reuters there is growing evidence that the first round of global vaccinations may offer enduring protection against SARS-CoV-2, the virus that causes COVID-19, and its most worrisome variants discovered to date.
Some of those scientists expressed concern that Big Pharma executives are conditioning people's minds.
"We don't see the data yet that would inform a decision about whether or not booster doses are needed," said Kate O'Brien, director of the Department of Immunization, Vaccines and Biologicals at the World Health Organization (WHO).
O'Brien said the WHO is forming a panel of experts to assess all variant and vaccine efficacy data and recommend changes to vaccination programs as needed.
Dr. Monica Gandhi, an infectious disease doctor at the University of California, San Francisco, said decisions on whether boosters will be needed "will best be made by public health experts, rather than CEOs of a company who may benefit financially."
Gandhi is taking a dig at Big Pharma executives who have been actively promoting COVID-19 booster shots. (Related: Big Pharma companies begin push for coronavirus booster shots, with no end in sight.)
Pfizer CEO Albert Bourla said people who've gotten both doses of the Pfizer-BioNTech jab would likely need a third shot within 12 months and might need an annual shot thereafter.
"There are vaccines like polio vaccine that one dose is enough, there are vaccines like pneumococcal vaccine that one dose is enough for adults, and there are vaccines like flu that you need every year," Bourla said. "The COVID virus looks more like the influenza virus than the polio virus."
Pfizer and BioNTech announced last month that they were testing a third dose of their COVID-19 vaccine to better understand the immune response against new variants of the virus.
The companies believe their current two-dose vaccine will work against the South African variant and the one first found in the United Kingdom. But the studies will allow the vaccine makers to be prepared if and when more protection is necessary, the companies said.
Johnson & Johnson CEO Alex Gorsky started using the narrative in February when he told CNBC that people may need to get vaccinated against COVID-19 annually, just like seasonal flu shots.
Meanwhile, Moderna CEO Stephane Bancel aims to produce a vaccine by the fall that targets a variant first identified in South Africa and expects regular boosters will be needed. In March, the National Institutes of Health (NIH) began testing a variety of offerings from Moderna to use as a third shot designed to boost immunity protection as concern grows about emerging variants.
Dr. Tom Frieden, former director of the Centers for Disease Control and Prevention (CDC), finds it inappropriate for Big Pharma executives to say that people will need an annual booster shot of the COVID-19 vaccine.
"There is zero, and I mean zero, evidence to suggest that that is the case," said Frieden. "It's completely inappropriate to say that we're likely to need an annual booster, because we have no idea what the likelihood of that is."
Responding to the criticism, a Pfizer spokeswoman said the company expects a need for boosters while the virus is still circulating widely. That could change once the pandemic is more firmly under control.
Earlier this year, evidence emerged that mutant versions of the virus might evade protection offered by vaccines. Laboratory studies showed that the South African variant could produce up to eight-fold reductions in antibody levels among people vaccinated with the Pfizer or Moderna vaccines.
Clinical trial data also showed that vaccines from AstraZeneca, Johnson & Johnson, and Novavax were less effective at preventing infections in South Africa, where the variant is widespread.
These studies prompted drug companies to start testing booster doses of their vaccines and to develop shots that target specific variants of the virus.
However, more recent research suggests that the Moderna and Pfizer/BioNTech vaccines produce high levels of protective antibodies to create a "cushion effect" against the known variants, said Dr. Anthony Fauci, head of the National Institutes of Allergy and Infectious Diseases (NIAID).
Several studies suggest that T cells – a type of white blood cell that can target and destroy already infected cells – may help prevent severe COVID-19 and hospitalization. NIAID researchers found that T cells in the blood of people who recovered from the original virus could still fight off infections caused by the concerning variants found in the UK, South Africa and Brazil.
"It's quite possible" that boosters would not be needed, Fauci told Reuters. "It is conceivable that the variants will not be as much a problem with a really good vaccine as we might have anticipated."
Moderna President Stephen Hoge expects boosters will be needed to keep immunity levels high, due in part to vaccine hesitancy. As long as the virus is circulating widely, people at high risk of severe illness may need to boost their immune protection, Hoge said. (Related: As Americans reject dangerous COVID vaccines, US states and cities see an increase in unused vaccine doses.)
Health authorities in the U.S., UK, the European Union (EU) and Israel have assured their populations that they are ready for such eventuality.
"It's a huge concern that wealthy countries would begin administering booster doses and further constraining supply of people's first dose of vaccine," said Rajeev Venkayya, head of global vaccines for Takeda Pharmaceutical Co.
Richard Hatchett, chief executive of the Coalition for Epidemic Preparedness Innovations (CEPI), said vaccine makers are right to plan ahead for boosters given the uncertainty over what will be needed in the long run. Governments can then decide for themselves whether to buy the products, he said.
The U.S. is preparing to have such products on hand for Americans, while the EU, UK and Israel have ordered new supplies of COVID-19 vaccines to deploy as protective boosters.
Andy Slavitt, senior advisor to President Joe Biden's COVID response team, said during a press briefing last month that the White House is preparing for the potential need for COVID-19 vaccine booster shots.
"I can assure you that when we do our planning, when the president orders purchases of additional vaccines as he has done and when we focus on all the production expansion opportunities that we talk about in here we very much have scenarios like that in mind," he said.
Global spending on COVID-19 vaccines and booster shots could total $157 billion through 2025, according to U.S. health data firm IQVIA Holdings. Pfizer has forecast sales of $26 billion from the vaccine in 2021 alone.
IQVIA, which provides data and analytics for the healthcare industry, said it expects the first wave of COVID-19 vaccinations to reach about 70 percent of the world's population by the end of 2022. Booster shots are likely to follow initial vaccinations every two years based on current data on the duration of effect of the vaccines, the report said.
Murray Aitken, a senior vice president at IQVIA, said that vaccine spending is expected to be highest this year at $54 billion with a global vaccination campaign underway. It is expected to decrease in succeeding years as tighter competition and vaccine volumes drive down prices.
The spending forecast for COVID-19 vaccines represents two percent of the roughly $7 trillion forecast for all prescription medicines during that time period, IQVIA said.
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