Robert Webster on H5N1 evolution, vaccines 12-11-06

[GenePalmer]

Re: Robert Webster on H5N1 evolution, vaccines 12-11-06

I'm sorry, I wasn't trying to knock the idea, and didn't intend to come across that way. I've competed for SBIR work before, so I have an idea how the DARPA grant process works. What I was trying to point out was that the successful product would essentially be for military use only, under circumstances that would make clinical trials moot, probably.

But as a bystander, I note that it's unlikely that the described process would be used to develop a civilian pandemic vaccine. And being a civilian, it's a little disappointing to realize how big the hurdles are for a fast-track vaccine.

Hey wetDirt,

I appreciate your comments. And I'm glad to see you took my little jibe
goodnaturedly. It really was meant with the best intentions. I admit the
"sharpen my razor" reference rankled me a bit, but what the hell, lively
debate should be a good thing. I would hope the US Congress might decide
the same. In any event I offer my apologies as well. You do have a knack
for the turn of a phrase. :tiphat:

To clarify the DARPA thing, I would offer that this initiative is not solely for
military purposes. I'd like to think that just as the DoD and even DoT were
involved in funding, supporting and promoting the human genome project,
the US government uses sometimes seemingly bizarre agencies to promote
research. My hope is that by exploring various technological platforms to
rapidly produce pandemic vaccines, the scope of this inititative is to
determine overall capabilities available. It might very well require the efforts
of many agencies, companies, institutes and manufacturing establishments
to produce enough vaccine to see us through a pandemic crisis.

To address AlaskaDenise's comments about cost, I would rather not
politicize this debate, but my 22 billion USD estimate was based on a
worldwide need of at least 300 million doses. Ideally worldwide "herd
immunity" might require something closer to 1 billion doses. Far beyond
any current capability to be sure. Yet the comparison with expenditures
in Iraq, any after-the-fact response to potential HPAI pandemic, such as
was seen in 1918-1919, could make those sums pale in comparison.

Crosby's "America's Forgotten Pandemic" was so subtitled because it barely
made the news! Perhaps because the mortaility rate was below 20%.
By contrast the 57 souls who perished in Indonesia in the past 14 months
as a result of H5N1 infection, represent a 76% mortality rate. This is truly
frightening.

Some of the comments in the current debate may seem discouraging,
even demoralizing, but I take some comfort in knowing the potential for
a pandemic crisis is being addressed. The recent WHO meeting grappling
with this issue was preceeded by a complacency that suggested a
growing opinion that this potential was being oversold; a flash-in-the-pan
akin to the SARS scare. Focus on rapidly evolving strains appearing in
Indonesia, and now again in China, have dispelled any concerns that we
can relax our vigilance.

My hat is off to Florida1 for creating this forum. Promoting rapid dissemi-
nation of information and informed debate will serve us all well as we
attempt to design strategies to control this potential threat.

Yesterday most people considered influenza as nothing more than a
nuisance - not more threatening than the common cold. The public is
now becoming more educated that this virus has the potential to be a
real killer.

I will be taking the weekend off. It's been a little rough getting back in
the saddle after the Holiday break. Thank you all for your warm welcome
and I look forward to more stimulating debate next week.

~gene

 

[Mingus]

Re: Robert Webster on H5N1 evolution, vaccines 12-11-06

The concept of a multi-clade vaccine is attractive in theory, but
extremely expensive in pratice. The reason it works for seasonal
trivalent vaccine production is because those viruses grow so well
in embryonated hens eggs. To be cost effective pharma wants to
produce a vaccine that costs about a buck a dose to manufacture.
Each new strain added to the mix dilutes out the others.

When you consider the investment made in Sinovac to produce
H5N1 vaccine in China it works out to closer to $75/dose. Multiply
that by the minimum population that would need to be vaccinated
to provide herd protection and I get something like 22 billion USD.
Sinovac makes a split virus vaccine based on A/Vietnam/1194/04;
a single strain. If costs double for each strain you add... well,
who can afford to foot this bill?

Thank you very very much, You answered a question I had since months:tiphat:
You are in the field as I can see.

I answer to the bolded quote expressing my theoretical understanding.

Have you considered that the cost of a multiclade vaccine for sister strains that never differ more than 96% will not need to cost double each strain you add because parts of their immunisation power will work for the other strain.
This is called crossed immunity & there is more when the strains are "sister" ( e.g.more than 95% )
Cross-immunity is a well documented phenomenon, not a chimeric idea.

This has to be tested before we can conclude the financial loss of such enterprise.


The article posted by Florida1 also give us a hint that a vaccine including the matrix protein but not necessarily the np proteins will enhance the chance of for a stonger cross-immune reaction.

Don't get dazzed by the universal vaccine rethorics but I would like that the vaccine industry circle consider the broad cross-immune vaccine idea.

Ex: I would see a a tree-clades split virus vaccine that include the matrix gene & the H5 & the NA of H5N1 at least. It won't need tree time the simple vax dose. This must be checked in a pilot study at least.


Thanks for listening to our concern

 

[gsgs]

Re: Robert Webster on H5N1 evolution, vaccines 12-11-06

I'm confused. A 3valent vaccine costs more thn the sum of the
3 single vaccines ? Why can't we use 3 single vaccines then ?

 

[AlaskaDenise]

Re: Robert Webster on H5N1 evolution, vaccines 12-11-06

Regarding costs...

- annual per student cost of K-12 US education = $9000

- cancer treatment (1 of 3 will get during lifetime) average is $5000/cycle, & immune boosting Neulasta shot = $3000 wholesale.

Who's to say what's "too expensive"? Shouldn't that be a consumer decision? Just because something is not affordable for the poor, is no reason not to produce it. I'm all for affordability, but something is better than nothing.

I agree with Robert Webster, when he said we may not have the "perfect" solution and need to consider doing whatever we can, like cross-reactive immunity or prepanemic vaccines.

While there is no way of knowing before a pandemic starts exactly how well the vaccine will work, the risks of doing nothing could be far greater. "Stockpiling pre-pandemic vaccines is more valuable than people realise," Robert Webster of St Jude Children's Research Hospital in Memphis, Tennessee, told a flu conference in Singapore last month. "It may not necessarily protect you from infection, but it will probably stop you dying."

from http://www.futurepundit.com/archives/003527.html

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