According to FDA officials, we need to determine if we need a new shot this fall by June.

Until early summer, the FDA will ask whether vaccine makers need to modify existing Covid shots to target different viral variants to avoid another surge that could occur this fall. The decision needs to be made, said the chief executive officer of the drug regulator.

Dr. Peter Markes, who heads the FDA office for vaccine safety and efficacy, will make a decision to the drug regulatory advisory board on Wednesday to make shots available in the fall by June. He said he needed it. Marks said the United States could face another wave of infection at that point as the virus continues to evolve as immunity from current vaccines declines.

At the conference, senior Biomedical Advanced Research and Development official Robert Johnson said that the biggest challenge in updating shots was coordinating between vaccine makers and focusing on the correct Covid variant. He said it was to confirm.

Pfizer, modern And other vaccine makers are conducting clinical trials with Omicron-based shots. However, the two companies are not currently coordinating new vaccine formulations, according to Jerry Weir, head of the FDA’s virus products division. Members of several FDA advisory boards say public health authorities need to develop a unified approach across vaccine manufacturers, as well as their job of updating influenza vaccines targeting new strains each year. Said.

Dr. Paul Offit, a member of the FDA Commission, said the CDC needs to take the lead in deciding when the vaccine will be ineffective against serious illnesses, so the FDA and the National Health Study Places transfer with new shots that can work with companies to determine the best path.

“At some level, the company is like directing a conversation here,” Ofitt said. “I often hear that companies currently have vaccines that are specific to Omicron, or that can be linked to the flu vaccine. It shouldn’t come from them, it really has to come from us.”

FDA officials have proposed using the process of developing a new influenza vaccine as a guide for changing Covid shots. Each year, the World Health Organization makes recommendations on the composition of influenza vaccines. Based on the Commission’s recommendations, the FDA will make its own decision as to which shares should be fired at the United States.

Unlike the predictability of influenza, uncertainties about Covid’s evolutionary trajectory make it difficult to determine how a vaccine needs to be updated or changed. increase.

Three doses of the Pfizer or Moderna vaccine were more than 80% effective in preventing the hospitalization of healthy adults during the Omicron wave, according to CDC data presented at the conference. However, the vaccines from both companies are still based on the original version of the virus that emerged in Wuhan, China, and have been significantly less effective against infection since the outbreak of the pandemic.

According to Trevor Bedford, a virologist at the Fred Hutchinson Cancer Research Center, Covid mutated two to ten times faster than influenza, depending on the strain of the latter virus. Bedford said he hopes that the peplomers that the Covid virus uses to invade human cells will continue to evolve. Vaccines target spikes and mutations in proteins can reduce the effectiveness of shots.

According to Bedford, the most likely scenario for next year is Omicron, whose variants will become more contagious and evolve to further escape immunity from vaccination and infection. However, he said it is difficult to predict whether another highly mutated variant will emerge that overturns the pandemic response, as Omicron did in the winter.

“I’m not really sure if these large outbreak viruses are a common feature or a rare feature of the unique SARS-CoV-2 evolution,” Bedford said in the scientific name of the virus that causes Covid. Said using.

In the case of influenza, Johnson said vaccine makers can plan their production in advance based on a stable seasonal market. However, according to Dr. Kanta Subbarao, a virologist working on influenza at the World Health Organization, it is not yet clear whether Covid will follow a predictable seasonal pattern similar to influenza.

Members of the FDA committee say that a central issue in renewing vaccines is determining which indicators public health authorities should use to determine when shots are no longer effective. Said. According to Dr. Cody Meissner, an infectious disease expert at Tufts University School of Medicine, scientists have not yet determined whether the specific antibody levels produced by the vaccine provide clear protection against the virus.

As a result, public health officials will have to rely on hospitalization rates to determine if the vaccine has lost its effectiveness, Meissner said. However, it is not clear whether national hospitalization data consist primarily of patients hospitalized for the virus or those who are positive after admission for other reasons. Meissner pointed out Massachusetts data showing that 65% of the 219 people admitted to Covid as of April 5 were actually admitted for reasons other than the virus.

Dr. Amanda Korn, a CDC employee, told the Commission that repeated boosts are not a sustainable public health strategy. Vaccines for hospitalization remain highly effective, and society may have to accept certain levels of infection, which can be treated with antiviral drugs currently on the market, Korn said.

Last week, the FDA approved a fourth shot for adults over the age of 50 without consulting the committee. Divided scientists and doctors, Some believe that there is not enough data to support additional shots. Marks said the FDA did not consult the committee. This is because drug regulators have seen approval as a way to give people additional protection to those who are more vulnerable to severe illness until a broader decision is made for the rest.

“I think we have the idea that we are very involved and can’t help people as often as we do,” Marks told the committee. “We first acknowledged that this additional fourth boosted dose, which was approved, was a temporary measure until we were ready for the possibility of the next booster in light of new data. “Mr. Marks said.