According to an FDA official, vaccine manufacturers have until early summer to determine whether they need to modify existing Covid shots in order to prevent another surge of cases this fall.

The FDA’s office for vaccine safety, efficacy and effectiveness, Dr. Peter Marks told Wednesday’s drug regulator advisory committee that the FDA would have to make a decision by June to ensure shots are available this fall. Marks stated that there could be another outbreak in the United States because the virus is constantly evolving and immunity diminishes from current vaccines.

Robert Johnson was a top official of the Biomedical Advance Research and Development Authority. He stated that updating the shots will require coordination among the vaccine producers to ensure they focus on the appropriate Covid variants.

Pfizer, ModernaOmicron-based vaccines are being tested by other vaccine companies. Jerry Weir from the FDA’s viral products division said the companies don’t yet coordinate on new vaccine formulations. Multiple FDA advisory panel members suggested that the public health authorities should develop a common approach to vaccine makers. This is similar to how they updated the flu vaccine every year in order to combat new strains.

Paul Offit is a member of FDA’s committee. He said that the CDC must decide when the vaccines against severe disease are not effective. This will allow the FDA and National Institutes of Health to work together with the companies in order to identify the best course of action for a fresh shot.

Offit explained that the conversations are dictated by the companies at some point. It is common to hear of companies now possessing an omicron-specific vaccine. This means that they have the ability to link it with the influenza vaccine. They shouldn’t be able to produce it, they must make it.

FDA officials recommended that Covid shots be modified by using the FDA process to develop new flu vaccines. The World Health Organization issues a recommendation every year about flu vaccine composition. Based on the recommendation of its committee, FDA makes their own decision about what strain should be used in shots to protect Americans.

The uncertainty over the trajectory of Covid’s evolution, unlike the predictability of the flu, makes it difficult to determine how the vaccines should be updated — or if they even need a change at all.

According to CDC data, three doses of Moderna or Pfizer’s vaccines prevented hospitalizations among healthy adults in the omicron waves. The vaccines used by the companies are still built on the original virus from Wuhan in China and have seen a significant drop in effectiveness since then.

Trevor Bedford of Fred Hutchinson Cancer Research Center, a virologist on Covid, stated that the virus has evolved up to 10x faster than flu. Bedford stated that he believes the Covid virus’ spike protein (which invades human cells) will continue to evolve. The spike protein is the vaccine target and the shot’s effectiveness can decrease as it mutates.

Bedford believes that the best scenario in the near future is for omicron (and its subvariants) to evolve into more transmissible strains and escape from infection. He said that it is difficult to predict whether another variant with a high level of mutation will emerge and disrupt the pandemic response like omicron over the winter.

Bedford stated that “we don’t really know if these wildly divergent virus will be a common feature or a rare feature in endemic SARS–CoV-2 evolution,” using Covid as the scientific name.

Johnson stated that the flu vaccine maker can develop production plans ahead of time based upon a steady seasonal market. According to Dr. KantaSubbarao (a World Health Organization virologist working on flu), it is not clear whether Covid will have a similar seasonal pattern to flu.

FDA committee members stated that the main question when updating vaccines is how public health officials should determine when shots are no longer effective. According to Dr. Cody Meissner at Tufts University School of Medicine, scientists have yet to determine if an antibody level that is generated by vaccines provides clear protection against the virus.

Meissner stated that public health officials will need to use hospitalization rates as a way to assess if the vaccine has lost its effectiveness. But it is not yet clear whether national hospitalizations are primarily comprised of people admitted for the virus or patients who test positive following admission. Meissner cited data from Massachusetts showing that 65% of 219 Covid-infected patients admitted as of April 5, were in fact not hospitalized for the virus.

Amanda Cohn (CDC official) told the committee that repeated boosters are not sustainable. Cohn indicated that vaccine effectiveness in preventing hospitalizations remains high. Society may need to be willing to take a level of infection it cannot treat using antiviral medications currently available.

Last week, the FDA approved fourth shots for adult patients over 50 without consulting with the committee. This is a move that was not supported by other agencies. divided scientists and physicians,Many people feel that the data is not sufficient to warrant additional shots. Marks stated that the FDA did not consult with the committee as the regulator of drugs viewed authorizations as an attempt to provide additional protection for people who are more susceptible to serious disease until the FDA makes a wider decision.

Marks stated that he believes everyone is on board with Marks’ belief that people can only be boosted as often as they are. Marks stated, “I am the first to admit that the additional booster that was approved was a temporary measure while we put things in place for a potential next booster given emerging data.”