"The most pernicious contention of the lot is that ‘misleading results from animal experiments have proved tragic or fatal when applied to children and babies’. This fundamentally misunderstands the purpose of animal research.

Animal activists like to quote adverse drug reactions as if they are trump cards. The logic goes like this: drug side effects sometimes kill; all drugs are tested on animals, therefore animal experiments are deadly. This is a non sequitur. That one event occurs after another does not mean it happens because of it.

It is true that animals are imperfect models for humans, and that dangerous errors would result if they were relied on in isolation for medical testing — which is why that never happens. Animal experiments are performed early in research for two chief purposes. They help scientists to understand basic biological processes that can inform the design of therapies, and then they are used in preliminary toxicity tests.

The key word is preliminary. Before a drug reaches the market, it must pass through three stages of clinical trials on humans, each one more rigorous and involving more patients than the last. The relatively small animal studies are designed to assess potentially damaging effects on a living body before a decision is taken to move to the first human safety trials."