Sir, Nicholas Wilson points out that the recent drug trial fiasco at Northwick Park Hospital is an indictment of the scientific validity of animal testing (Letters, April 14). In fact, animal tests are so poorly predictive for humans that nine out of ten drugs that pass animal tests fail in human trials.

Advocates of animal testing deny this and deceive the public with claims such as "Some of the major advances in the last century would have been impossible without animal research". The Advertising Standards Authority recently ruled that this claim was misleading and should not be repeated. Patient safety group Europeans for Medical Progress supported by 83 per cent of GPs and 226 MPs suggests a scientific evaluation of animal testing to settle this matter once and for all: see www.curedisease.net The truth is that superior human-based tests would reduce the shocking death toll from adverse drug reactions.

Kathy Archibald, Director, Europeans for Medical Progress, London