Swine Flu vaccines appear to work well without adjuvants;
NY TIMES article on ADJUVANTS in H1N1 vaccine
September 22, 2009 · Leave a Comment
Benefit and Doubt in Vaccine Additive
Published: September 21, 2009
The question;
Are Americans obligated to use an unproven vaccine to help protect people in other countries from the flu pandemic?
That is the crux of a debate over adjuvants — a class of substances that somewhat mysteriously increase the potency of vaccines. Early studies suggest that adjuvants (pronounced AD-joo-vants) could allow four times as many people to be immunized against the H1N1 pandemic influenza with a given amount of vaccine. So with the world facing possibly severe shortages of vaccine, the World Health Organization and some health experts have been calling for the use of adjuvants to stretch the vaccine supply.
Adjuvants concern the public;
“If you add what the public would perceive as another unknown there, there’s a concern that people would be reluctant to get vaccinated,” said Dr. Anthony S. Fauci, director of the National Institute of Allergy and Infectious Diseases.
Furthermore, officials say, one reason to use adjuvants is that they can increase a vaccine’s potency against a virus to which it is poorly matched. But the swine flu vaccine is well matched to the virus, which has not mutated.
Swine Flu vaccines appear to work well without adjuvants;
Still, Dr. Tadataka Yamada, president of the global health program at the Bill and Melinda Gates Foundation, said that most of the world’s population of six billion people, mostly in poorer countries, would still be without vaccine, especially early in the pandemic.
Shortage;
Less vaccine than expected has been produced so far because of manufacturing problems. “Over all, there is still clearly a shortage of vaccine supplies,” said Dr. Andrin Oswald, chief executive of the vaccine business at Novartis. Except for the United States, Dr. Oswald said, most countries ordering from Novartis have taken vaccine with adjuvant.
Companies developing adjuvants assert their importance in vaccines;
Even if adjuvants do not save the day in this pandemic, experts say they will become increasingly important for vaccines against all manner of diseases.
That is because many vaccines now being developed “simply don’t work that well without an adjuvant,” said Dr. Thomas Monath, acting chief medical officer of Juvaris BioTherapeutics, a company developing adjuvants.
Such as;
Intercell, an Austrian company, is developing an adjuvant for flu shots in a patch worn on top of the injection site for a few hours.
They say they know more now about the additives;
“For the longest time, adjuvants were sort of a witch’s brew of substances, empirically designed,” said Bali Pulendran, a professor of pathology at Emory University. “What was once a black box is now being illuminated at the mechanistic level by new advances in immunology.”
New adjuvant to be used;
An advisory committee to the F.D.A. recently recommended approval of Cervarix, a vaccine against the virus that causes cervical cancer. The vaccine, made by GlaxoSmithKline, uses an adjuvant containing a bacterial lipid. (Gardasil, the Merck cervical cancer vaccine already in use, has an aluminum adjuvant.)
Squalene or similar adjuvants are still favored by vaccine makers;
Alum is not used in flu shots because it has little effect. But Novartis and GlaxoSmithKline are selling pandemic flu vaccines containing newer adjuvants they have developed. They are oil-in-water emulsions of squalene, a lipid that is found in the body. Glaxo’s also contains vitamin E.
A seasonal flu vaccine containing Novartis’s MF59 adjuvant has been used in Europe since 1997. Glaxo’s adjuvant, called AS03, is in a vaccine approved in Europe for use against the H5N1 bird flu, which spurred fears of a pandemic a few years ago.
Bird Flu vaccines did not seem to work well.
Thinking the swine flu might pose the same problem, federal officials ordered $700 million worth of adjuvant from Novartis and Glaxo.
If the adjuvants were used, they would have to be combined with the vaccine before the injection was given. And because the adjuvants have not been approved by the F.D.A., they would fall under a so-called emergency use authorization.
H1N1 does not require an adjuvant;
. . . in the last two weeks it has been learned that the vaccines against the H1N1 virus stimulate a strong response on their own. A single shot containing 15 micrograms of antigen — the same amount used for each strain in a seasonal flu vaccine — should confer adequate protection for most people.
Federal officials admit risk of autoimmune disease from use of adjuvants;
Preliminary data from GlaxoSmithKline show that a vaccine with an adjuvant might use only one-fourth as much antigen. But federal officials say the savings are not large enough to offset the possible risks and extra complexity of using the adjuvants.
While adjuvants tend to increase the temporary pain, swelling or fatigue caused by a vaccine, the main concern is whether they might cause an autoimmune disease, like rheumatoid arthritis, in which the immune system attacks the body’s own tissues. Some animal studies have suggested that possibility.
Of course;
Adjuvant makers say there is no cause for concern with the flu vaccines.
But;
Novartis says more than 40 million doses of vaccine with its adjuvant have been used in Europe, with no signs of problems. But Dr. Fauci, of the National Institute of Allergy and Infectious Diseases, said Novartis’s adjuvant had been used mainly among the elderly, who tended to have weaker immune systems. There is less data, he said, on its use among children, younger adults and pregnant women.
Read the unabbreviated article; http://www.nytimes.com/2009/09/22/health/22vacc.html?_r=1&th&emc=th
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