MHRA has released its preliminary report on the clinical trial of TGN1412. So now we know that there were no manufacturing errors, contamination or dosing errors in the first-into-humans test of the monoclonal antibody treatment TGN1412.
What we don’t know yet is what did go wrong. Because the serious adverse reactions were rare and unprecedented, further enquiries are needed. But it seems likely that this novel biological treatment triggered stimulation instead of regulation of the immune system. For some reason this didn’t occur in animals that were given 500 times the dose ultimately given to the human volunteers. We know that TGN1412 activates CD28 on the surface of immune system cells, but many different cells carry the CD28 receptor. The failure to predict immune stimulation suggests that scientists needed to know far more detail about the effects of TGN1412 before it was licensed for human volunteer studies. That is, we should have had more studies in human tissues and in animals.
Indeed, the scientific magazine Science said a couple of weeks ago:
"Research is needed to define better animal models of the human response to CD28 agonists” and extra precautions need to be taken “when antibodies are used to stimulate rather than neutralize components of the immune system.”
Science, 24 March 2006
However, in a letter to The Independent today, Dr Gill Langley, Director of the Dr Hadwen Trust, a charity that funds alternatives research, said “The health of volunteers must be safeguarded, but so must the crucial role of volunteer trials”. So far so good. But she then repeated the tired old animal rights mantra suggesting the animal tests were at fault:
”... seven organisations supporting non-animal research techniques, have proposed more test-tube research and safer volunteer studies, using drug microdoses too low to cause side effects. In January, the US Food and Drug Administration said the same. This approach could improve human safety and relieve animal suffering.”
Gill Langley, Dr Hadwen Trust
Well, she would say that, wouldn’t she? Of course human tissue studies and animal studies and a whole lot more preceded the clinical trials. But Dr Langley can’t resist placing blame on the animal studies. What dose does she think was given to the human volunteers? One 500th that given to monkeys, ie a microdose. We need more human tissue studies AND animal studies, and less recourse to unthinking animal rights dogma.
