[snips]
There is agreement on one point: The current seasonal flu vaccine will not protect against the novel virus. If authorities decide that a swine-flu vaccine is necessary, a new one will have to be formulated.
Some manufacturers have grown all the vaccine virus needed for their production run, have moved the result to bulk storage for later packaging, and therefore could be ready to start a limited-production test of the new virus if necessary. But others are not done: According to the Centers for Disease Control and Prevention, some manufacturers have had difficulty growing one of the three major seasonal vaccine components, a strain that induces immunity to the family of viruses known as influenza B.
That lag raises the possibility that manufacturers could be asked to short-circuit work on the seasonal vaccine in order to begin handling the seed strain of the novel virus, a move that would reduce the amount of vaccine available in the northern hemisphere next winter.
"Some of the manufacturers may be 60% through, some of the manufacturers may be a little bit less, and not the same level either for the three components," Kieny said. "We are in discussion with them to try to see at what moment it might be the best solution to stop the seasonal and to start the pandemic" formula.
Rumors are circulating among some flu scientists that the strain being used at the CDC for the vaccine seed strain is not growing well in eggs. The WHO and CDC appeared to acknowledge this Friday, disclosing that they are preparing two seed strains for manufacturers: one that was naturally reassorted by allowing viruses to mix in eggs, and another tuned via a patented process called reverse genetics that cuts and pastes genes from the swine virus with a non-pathogenic virus in order to achieve the highest possible growth rate. Manufacturers will be allowed to choose, the agencies said.
Rear Admiral Anne Schuchat, MD, interim deputy director of the CDC's Science and Public Health Program, told Congress Thursday that US manufacturing capacity would allow for the production of 600 million doses, or two shots for every US resident. Kieny said Friday the current global capacity is approximately 700 million doses. A report released in March by the International federation of Pharmaceutical Manufacturers and Associations puts current global capacity at 917 million doses—but it relies on assumptions that include an average dose of 9 micrograms, not 15.
Nevertheless, plants with faster, cleaner next generation-technology, cell culture, are not scheduled to come online in the United States for 2 more years.
If pilot lots pass clinical trials and move to full manufacture—a process that would take several more months—another significant hurdle remains: how to get the vaccine past government regulators.
Combining the new vaccine with the existing vaccine into a quadrivalent (four-strain) product, while potentially more acceptable to consumers, would face far more regulatory hurdles because it would represent a new formulation—and, if it were contaminated or held up by manufacturing problems, could imperil potentially the entire seasonal vaccine supply.
Pandemic planners have pushed for adjuvant licensure in the United States for years; they were first called for after the 1957 pandemic. But so far, only one adjuvant has been licensed in the United States, and regulators have said that in order to be approved, any adjuvanted vaccine must be tested using the exact adjuvant-antigen dosage that will be marketed—thus requiring an additional layer of testing that is unlikely to fit the need for speed in achieving a pandemic vaccine.
http://www.cidrap.umn.edu/cidrap/content/influenza/swineflu/news/may0109vaccine.html
There is agreement on one point: The current seasonal flu vaccine will not protect against the novel virus. If authorities decide that a swine-flu vaccine is necessary, a new one will have to be formulated.
Some manufacturers have grown all the vaccine virus needed for their production run, have moved the result to bulk storage for later packaging, and therefore could be ready to start a limited-production test of the new virus if necessary. But others are not done: According to the Centers for Disease Control and Prevention, some manufacturers have had difficulty growing one of the three major seasonal vaccine components, a strain that induces immunity to the family of viruses known as influenza B.
That lag raises the possibility that manufacturers could be asked to short-circuit work on the seasonal vaccine in order to begin handling the seed strain of the novel virus, a move that would reduce the amount of vaccine available in the northern hemisphere next winter.
"Some of the manufacturers may be 60% through, some of the manufacturers may be a little bit less, and not the same level either for the three components," Kieny said. "We are in discussion with them to try to see at what moment it might be the best solution to stop the seasonal and to start the pandemic" formula.
Rumors are circulating among some flu scientists that the strain being used at the CDC for the vaccine seed strain is not growing well in eggs. The WHO and CDC appeared to acknowledge this Friday, disclosing that they are preparing two seed strains for manufacturers: one that was naturally reassorted by allowing viruses to mix in eggs, and another tuned via a patented process called reverse genetics that cuts and pastes genes from the swine virus with a non-pathogenic virus in order to achieve the highest possible growth rate. Manufacturers will be allowed to choose, the agencies said.
Rear Admiral Anne Schuchat, MD, interim deputy director of the CDC's Science and Public Health Program, told Congress Thursday that US manufacturing capacity would allow for the production of 600 million doses, or two shots for every US resident. Kieny said Friday the current global capacity is approximately 700 million doses. A report released in March by the International federation of Pharmaceutical Manufacturers and Associations puts current global capacity at 917 million doses—but it relies on assumptions that include an average dose of 9 micrograms, not 15.
Nevertheless, plants with faster, cleaner next generation-technology, cell culture, are not scheduled to come online in the United States for 2 more years.
If pilot lots pass clinical trials and move to full manufacture—a process that would take several more months—another significant hurdle remains: how to get the vaccine past government regulators.
Combining the new vaccine with the existing vaccine into a quadrivalent (four-strain) product, while potentially more acceptable to consumers, would face far more regulatory hurdles because it would represent a new formulation—and, if it were contaminated or held up by manufacturing problems, could imperil potentially the entire seasonal vaccine supply.
Pandemic planners have pushed for adjuvant licensure in the United States for years; they were first called for after the 1957 pandemic. But so far, only one adjuvant has been licensed in the United States, and regulators have said that in order to be approved, any adjuvanted vaccine must be tested using the exact adjuvant-antigen dosage that will be marketed—thus requiring an additional layer of testing that is unlikely to fit the need for speed in achieving a pandemic vaccine.
http://www.cidrap.umn.edu/cidrap/content/influenza/swineflu/news/may0109vaccine.html