Panel reluctantly backed flu vaccine to FDA

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(CNN) -- Members of an advisory panel that backed this year's flu vaccine expressed doubts about its potential effectiveness before recommending it for the Food and Drug Administration's approval.

Some said they were concerned the vaccine would not provide as much protection against the Fujian strain of flu that was thought most likely to dominate this year's flu season, according to a transcript of the group's deliberations.

The Fujian strain, which emerged in the Far East, is now responsible for 75 percent of U.S. flu cases, the Centers for Disease Control and Prevention said.

But drug makers could not culture the Fujian strain in a way to meet FDA standards, forcing the advisory committee to make this year's flu vaccine the same as it was last year.

The committee's decision in March has come under a microscope now because the flu is reaching near epidemic proportions in the United States. (Full story)

Dr. Theodore Eickhoff, a professor of infectious diseases at the University of Colorado Health Sciences Center in Denver, said he was voting reluctantly to recommend the current vaccine, according to the transcript.

"For the first time in many years of participating in these deliberations, I must add that I am very uncomfortable with that recommendation," Eickhoff said.

The final vote in a March 18 meeting was 17 in favor of the current vaccine, two abstentions and one opposed. The FDA later approved the vaccine.

Dr. Peter Palese, chief of microbiology at New York's Mount Sinai Hospital, was the sole member to vote against the recommendation of the Vaccine and Related Biological Products Advisory Committee.

A number of people said they felt they were given no choice, according to the transcript.

"I would prefer that we move to an A/Fujian-like strain," said Dr. Pam Diaz of the Chicago, Illinois, Department of Public Health. "However, it seems from a regulatory standpoint, in terms of manufacturing, that we have our hands tied."

Nancy Cox, chief of the influenza branch at the CDC, told the group that manufacturers had been unable to grow the Fujian strain in chicken eggs -- the only FDA-approved method of reproducing the virus for use in vaccines.

"It's just not working this time," she said. "We don't know why."

But, she added, when lab workers extracted the Fujian strain from dog kidneys and then put it into chicken eggs, it grew well.

The prospect of using a virus extracted from an animal did not sit well with Dr. Karen Midthun, director of the FDA's office of vaccines research and review, who said it could pose a risk to vaccine recipients if it turned out to be contaminated.

"One really needs to know a lot about the cells that were used," she said. "They need to be qualified, characterized, to really address the different safety issues that we feel need to be addressed."

Palese disagreed, according to the transcript.

"One can make a reasonable argument" that there is a theoretical possibility that cells used in the approved vaccine could contain contaminants "and that we are perfectly happy to accept that," he said.

"We are ... not making the best vaccine decision if we don't allow the Fujian type to be part of this new formulation."

Palese downplayed the possibility of contamination, calling it "a potential very, very minimal risk."

He added, "If we have the technological abilities to make better vaccines, then we should make them, rather than sticking to old regulatory rules."

Reached by telephone Saturday at Mount Sinai Hospital, Palese said, "I would rather not comment."

Another member of the advisory panel, Dr. Samuel Katz, a virologist and infectious disease expert at Duke University Medical Center, was less reticent about Palese's lone vote in favor of adding the Fujian strain to this year's vaccine.

"Dr. Palese is the member of that committee most knowledgeable about influenza viruses," Katz told CNN in a phone interview from his home in Durham, North Carolina.

"He was the only one there with the knowledge about reassortment and recombination of influenza viruses to say that he felt that there should be some way to do that."

Nearing epidemic proportions in U.S.

The onset of this year's flu outbreak -- in October -- is earlier than in most seasons.

Flu is widespread in 24 states, and cases have been reported in all 50 states.

Last week, pneumonia and influenza were blamed for 7 percent of all deaths logged by the country's reporting system that includes 122 cities, just below the 7.6 percent that the CDC said would represent the epidemic threshold.

Only 25 percent of influenza viruses found so far are the Panama strain of Influenza A, which is contained in the current vaccine, according to the CDC.

Though studies have shown that the Panama strain will have some effect against the Fujian strain, reports quantifying that effectiveness will not be complete until after the flu season is over, the CDC said.

Dr. Michael A. Decker of Aventis Pasteur, one of two U.S.-based influenza vaccine manufacturers, said he would have included the Fujian strain if it were practical to do so.

"But it's also clear to me that trying to do so is likely to cause more problems than it will help," Decker said.

Given the problems in reproducing the virus, attempts to include it could have delayed production of the vaccine, which is a four-month process. It could have meant that supplies would not have been available on time, the industry representative said.

"The perfect vaccine, arriving in insufficient quantities and late, will protect fewer people than the less perfect vaccine arriving abundantly and on time," he said.

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