Judy Way (Letters, July 5) misleadingly blames the use of animals in medical research for the rare occasions when some medicines cause unwanted side-effects.

All drugs have to go through three phases of clinical trials on human volunteers before they are licensed for general release.

Typically, there are approximately 5,000 paid volunteers in these trials. If a drug successfully passes this hurdle, all it means is there is less than a one-in-5,000 chance of it causing unseen side-effects.

That low level of risk is good enough to satisfy the licensing authorities so, if anything is to blame, it is the clinical trials, not animals.

In response to Peter Allen, if animal-rights extremists were really interested in animal welfare they would support the use of animals in veterinary research.

But the main anti-vivisection groups oppose even this. Supporting medical research of which some involves the unavoidable use of animals does not mean you do not like animals.

Animal rights is an ideology which proposes animals should be given the same rights as humans. This Disneyland ideal runs counter to all human-animal relationships.

As for Mr Allen criticising Andrew Blake, who before his death was to have received an MBE, it takes guts to stand up to the violent and darker side of this extreme movement.

It takes even more guts to do it from your wheelchair. Andrew deserved such recognition for his tireless work.

Seriously Ill for Medical Research (SIMR) is a patients' group which supports the humane use of animals in medical research where necessary. Write to SIMR, PO Box 504, Dunstable, Bedfordshire LU6 2LU or see the web site, simr.org.uk

-Thomas Bromley, SIMR Executive Secretary