Calling all animal researchers & toxicologists - reliability question

John Mercer umbjm at montana.edu
Mon Mar 8 17:33:04 EST 1999


<greenrd at hotmail.com> wrote:

> I have a simple question. The reason I ask is because some antivivisectionists
> have gone so far as to claim that "no drug safety or efficacy results can be
> reliably extrapolated from any species to any other species".
> 
> My question: Where are the published, peer-reviewed studies that falsify this
> claim?

My answer: everywhere. You only need to look!

> To be more precise:

To equivocate and prevaricate, you mean?

> Can anyone supply a references for repeated studies

Isn't repeating studies on animals unnecessary and cruel?

> which
> demonstrate a reliable correlation between the toxicity and/or efficacy of
> drugs used to treat several laboratory-induced diseases in one species, with
> the toxicity and/or efficacy of those same drugs used to treat corresponding
> "naturally-induced" (i.e. not laboratory-induced) diseases in another?

Yes. The horrible accidental experiment of thalidomide with pregnancy is
a fine example of toxicity.

Humans: a wide spectrum of fetal toxicity varying from no effect at all
to fetal death, depending on the time of gestation at which thalidomide
is administered.

Multiple species of lab animals: a wide spectrum of fetal toxicity
varying from no effect at all to fetal death, depending on the time of
gestation at which thalidomide is administered.

Go to http://www4.ncbi.nlm.nih.gov/PubMed/ and search.

Keep in mind that "AR" religious dogma pretends that thalidomide ONLY
causes limb defects in humans. You swallow it whole, right?

> Several obvious points should be apparent: Post-hoc reviews of previous
> studies are likely to be invalid, because they would have to ignore
> unpublished studies - besides which, "approximately 1% of papers published in
> medical journals are scientifically sound",

A "quotation" without a source is worse than useless--it smacks of a
lack of integrity.

> so they would have to be very
> careful about which ones they chose. Testing only one drug is far too
> selective -

But how about a drug that the "AR" religious wackos dishonestly choose
as their own example, while omitting important facts?

> what is really at issue here is whether species-extrapolation is
> scientifically valid

Your use of "valid" here is deliberately vague. The correct term would
be "predictive."

> as a general deductive step,

You mean in drug testing, or in general?

> not whether there are
> correlations in the cases of particular drugs. Testing only drugs that are
> already known to demonstrate a correlation would also be selective, not to
> mention pointless since the results are a foregone conclusion (that's
> assuming that the original trials were sound, which is doubtful - see
> quotation above).

I saw a quotation, but without a source, it is meaningless. 

Why do "AR" pseudoscientists use quotations instead of data for their
arguments?

> Examining only laboratory-induced diseases in both species
> would do nothing to falsify another key claim of the antivivisectionists:
> that laboratory-induced diseases are *inherently* unscientific models of
> "naturally-induced" diseases.

But the antivivisectionists have failed to support their claim. There's
no reason for you to assume that it is valid.

> (Well, they might have to make an exception for
> radiation poisoning, say, which in *one* sense of the word is
> "naturally-induced" - in another sense it is highly unlikely to be, being
> caused by nuclear bombs etc.)

Or muscular dystrophy, or cystic fibrosis, or Griscelli syndrome (my
contribution), etc.

> I suspect there are no such studies,

Have you looked?

> and I suspect this is because those
> antivivisectionists are absolutely right.

Have *they* looked?

> If there are no such studies,

Aren't you getting ahead of yourself?

> then
> tell me, on what scientific evidence is species-extrapolation based?

Loads of evidence. Try thalidomide for starters.

> Please
> don't fob me off with talk of "anatomical and physiological similarities" -
> the scientific route is clear - in order to prove that it is reliable to
> extrapolate in such a manner, one must demonstrate a reasonably high
> correlation,

Leaving yourself a lot of room for weaseling, I see. ;-)

There's really no reason to continue if you refuse to define the terms,
you know. Here in the US we call that "moving the goal posts."

> by means of repeated, well-controlled, blind, unbiased,
> peer-reviewed studies.

Is that how the antivivisectionists arrived at their conclusion, Robin?

And what about you? Why are you posting here instead of going to your
nearest medical library?

Afraid of what you might find, perhaps?

> One might argue that we don't even require proof that an extrapolation from
> *human* clinical trial groups to the potential market of a human drug, a
> market which may span much of the world population geographically, is valid.

What do you mean by "valid"? 

Will you refuse to define this so you have loads of wiggle room?

> To which I say, indeed, good point.

Your modesty is touching.

> That children and adults often react
> differently to treatments is well-known - what other variations are there
> that we don't know about, or choose to ignore for the sake of profit?
> 
You tell me.

Why wasn't thalidomide approved for sale in the US, Robin?  

-- 
John Mercer



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