Comment by sploitable | Hacker News Reader

Comment by sploitable | Hacker News Reader

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In fact there are many counter examples. Thalidomide had no negative effects on non-human animals, but created notoriously deformed children in humans. Similary, I think it was paracetamol which when tested on some non-human animal is 100% lethal, and had they tested on those species then this common, essential medicine would never have progressed to the human trial stage. A classic case is the link between lung cancer and smoking. Millions of dollars of public money went to the big tobacco companies in the name of "cancer research". Dispite being able to induce lung cancer in dogs by restraining them and forcing the to chain smoke for hours on end, these were not the results they wanted. IIIRC, it took research with human volunteers before the scientific consensus that we have today came about because the "animal models" did not represent human physiology.

> Thalidomide had no negative effects on non-human animals, but created notoriously deformed children in humans

That's not actually true; it causes birth defects in animals as well. Only limited animal testing was performed before it was approved for use in humans; more extensive animal testing, which did demonstrate birth defects, was performed only after it had been withdrawn due to causing human birth defects.

https://pubmed.ncbi.nlm.nih.gov/12677202/

> Thalidomide had no negative effects on non-human animals, but created notoriously deformed children in humans.

Thalidomide was never approved for treating in nausea in pregnant women in the US. It was prescribed off label, but the FDA rejected it for that purpose.

Why did the FDA reject it if animal tests didn’t show deformities?

To be clear, that’s not a rhetorical question. I’ve heard rumors the FDA wasn’t convinced thalidomide would be effective - which is very different from worries over fetal abnormalities.

Do you know the background there?

I believe the studies were done with a single isomer, which was safe and is still available. The racemic mixture was sold commercially but never tested until later. IIRC the bench top process produced a single isomer, but the scaled up process messed with the chirality producing the racemic mixture.

Yeah this was the real problem with Thalidomide. It pops up as an example of "things to consider" in DD textbooks.

>In fact there are many counter examples

I think you inverted the meaning of the parent comment. They asked for exceptions where animal experiments do apply to humans, saying that the rule seems to be they don't.

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