Companies need several months to produce a new vaccine, so the deadline has come to choose a vaccine formula to be ready for distribution in October. The FDA is expected to make a final decision in the coming days.
However, no one knows what options will be available this winter, and it is reasonable to expect that any omicron variant included in the updated vaccine will be in the rearview mirror until the shots start to take off. updated vaccines It has been in human trials for months, including BA.1, but this variant has spread this winter and has already been captured by other versions of the omicro; Sub-options BA.4 and BA.5 are already in place half of the cases In the United States.
There is also uncertainty that updated vaccines will not really protect people better. The companies have modestly shown that they can activate antibodies that block higher levels of the virus, but it is unclear whether this will lead to better hospitalization or better protection against infection. The hope is that the updated vaccine will boost the immune response.
“Today we are being asked to have more or less a crystal ball,” said Arnold Monto, chairman of the FDA’s advisory committee and an honorary professor of public health at the University of Michigan School of Public Health.
During the discussion, many members of the committee said that the vaccine should be a multi-strain vaccine containing the original version of the virus and the omicron component. Many members and FDA officials preferred the BA.4 and BA.5 omicron subvariants, but some promised to include the BA.1 version of the omicron.
“In my opinion, given the speed of evolution [of the virus] If we wait longer, we will be behind eight balls, ”said Mark Sawyer, a professor of clinical pediatrics at the University of California, San Diego School of Medicine. “Public opinion is that the FDA is already delaying approval,” he said. I think we have enough information presented here today to move forward with the change in tension.
Vaccination companies, including Moderna, NovavaxPfizer and its German partner, BioNTech, sometimes provided conflicting information about potential strengthening strategies, leaving committee members in a triangle between overlapping and sometimes different outcomes.
Paul Offit, a vaccination specialist at Philadelphia Children’s Hospital, called the data “worryingly low” and voted against changing the strain. He asked if the modest difference in how modified vaccines cause an immune response was a big enough difference to turn them into a benefit for humans.
“I don’t think it’s right to ask people to take risks … we don’t feel comfortable with the level of protection we can get,” Offit said.
Each of the companies provided information to support their preferred strategy.
Modern, for example, a bivalent vaccination designed to protect against the original version of the virus and omicron BA.1 variant. The company said it could begin delivering the vaccine this summer, but warned that a vaccine containing BA.4 and BA.5 could take until late October or early November.
However, Pfizer and its German partner BioNTech found that a single variant of the virus, a vaccine targeting BA.1, was better than a dual formulation. The company also provided mouse data showing that a vaccine designed to combat the omicron sub-variants expected in BA.4 and BA.5 in the U.S. in the near future could trigger stronger and broader immune responses. The company will be ready to offer both versions of the vaccine by the first week of October.
The Novavax vaccine is not yet approved in the United States, but uses a different technology – delivery of viral protein brewed in the laboratory. The company has reported that additional doses of existing vaccines may be protective against even micron sub-variants. Clinical trials of its omicron amplifier are ongoing and results are expected in September.
Adam Berger, director of the National Institutes of Health’s Clinical and Health Research Policy Department, said the information presented at the meeting suggests that while the universal recommendation to change vaccines is preferred in terms of simplicity, the results show “no results.” It is not a one-size-fits-all answer to whether a voltage change is necessary.
A number of experts have expressed concern that the US could change the composition of the vaccine, which could be aggravated. global vaccine capital problems and ideas about vaccines. It was not clear whether the vaccine change would apply to adults or children. Several experts said they would like to see more tests if the vaccine is changed for children.
However, during the public commentary session, several parents eagerly requested that the vaccines be updated for all age groups, including the youngest children.
Expect vaccinations for children Under 5 was “long and unbearable,” said Kate Schenk, a mother of three. “We cannot allow this to happen again. Children should have the right to receive these updated amplifiers along with the old cohorts – not backward, unprotected. “
Peter Marx, director of the FDA’s Center for Biological Assessment and Research, said that half of Americans did not accept the amplifier, despite clear evidence that the third shot restored and expanded the defense. Even those who take amplifiers will become sensitive again over time as their immunity weakens.
“We believe that the better the vaccines adapt to the circulating strain, the better the effectiveness of the vaccine and the potentially better protective resistance,” Marx said.
However, even an updated vaccine will not reverse such a pandemic and provide excellent protection against the rapidly evolving and highly transmitted virus. Today, the increasing frequency of omicron sub-variants is unlikely to be encountered by the world in the fall. How well vaccines based on them will protect against future recurrences of the virus will not be known until they are used.
The process is compared to the selection of a flu vaccine each year. In some years, it is better suited to the more common influenza strains than others.
However, influenza is a different virus, and this meeting is the first step in a long-term challenge to try to develop a vaccination strategy.
“I would like to remind you that the parallel trace of the selection of very well-functioning influenza strains has been a process that has been appreciated for many years. And so we probably have a lot of work to do, ”said Jerry Weir, director of the Viral Products Department at the Office of Vaccine Research and Analysis. “It’s a different virus,” he said. We have a lot of work to do on the strain selection process for Covid vaccines. “
