Friday, February 8, 2013

ASO3 for the US avian flu stockpile / CIDRAP


I'm 3 months late on this.  Since this article came out, it became clearer that ASO3 caused narcolepsy in more countries than just Scandinavia and Ireland, and that adults were also at risk of developing narcolepsy after the vaccine.  And these are BAD cases of narcolepsy, not the minor cases I have seen in clinical practice.  There is also more Guillain-Barre with this vaccine.

But FDA asked the panel to comment on immunogenicity.  Sure enough, the vaccine does induce antibodies.  But we don't know if they work.  Not to worry.  After licensure, GSK can freely change the antigen.

FDA panel endorses H5N1 vaccine with adjuvant
Robert Roos * News Editor
Nov 15, 2012 (CIDRAP News) – A government advisory committee yesterday endorsed the safety and immunogenicity of an adjuvant-containing H5N1 influenza vaccine proposed for inclusion in the US pandemic emergency stockpile, signaling that it could become the first adjuvanted flu vaccine to win approval in the United States. 
On two unanimous votes, the Food and Drug Administration's (FDA's) Vaccines and Related Biological Products Advisory Committee (VRBPAC) said the immunogenicity and safety data on GlaxoSmithKline's (GSK's) H5N1 vaccine are adequate to support its licensure for use in adults. The aim is to strengthen the US stockpile for the threat of an H5N1 pandemic. 
The vaccine contains GSK's proprietary adjuvant AS03, which is used in several other GSK vaccines licensed in other countries. One of these, Pandemrix, used in Europe during the 2009 H1N1 flu pandemic, was linked with an increased risk of narcolepsy in children in Finland, Sweden, and Ireland. 
The purpose of the adjuvant is to induce a stronger immune response with less antigen or active ingredient, which AS03 achieves, according to GSK. The vaccine contains 3.75 micrograms (mcg) of antigen, compared with 15 mcg in standard flu vaccines without adjuvants. 
No seasonal flu vaccines used in the United States contain adjuvants, nor does the existing H5N1 vaccine in the US emergency stockpile. The government has acquired a supply of adjuvants for possible emergency use, but they are not part of a specific vaccine. 
The US Department of Health and Human Services (HHS) contracted with GSK to develop an H5N1 vaccine with antigen-sparing potential for use in the US Strategic National Stockpile, according to an FDA briefing document...
Another member, Gillian Air, PhD, said, "We don't know what these HI titers mean in terms of protection, but they've demonstrated this is immunogenic."

2 comments:

Anonymous said...

Does the ordinary flu vaccine routinely offered to 'at risk' groups (over 60s, diabetics etc) in the UK work and is it safe?

Meryl Nass, M.D. said...

It depends on the year (vaccine changes yearly) the strains circulating, and possibly other things. Last year's vaccine was of little to no benefit. It was claimed in the US this year's vaccine was 62% effective, though data from Denmark suggest that for the majority of flu cases in the elderly (Influenza A cases) there was no benefit or even a negative benefit (vaccine might increase cases of flu illness).

Although that sounds incredible, several studies have shown that flu cases may increase in the first two weeks after a particular flu vaccine is given, and in other situations (like 2009 Canada) a flu shot the year before approximately doubled your chance of developing the disease swine flu in 2009.