Radical new procedures may have to be introduced in Britain to regulate drug trials after six human volunteers suffered extreme reactions during a clinical test in London last week.
Dr David Glover, who for 10 years was chief medical officer at the biotech company Cambridge Antibody Technology, said: "What you need to do is understand the issues you face and find creative solutions. Genetically engineered mice with a humanised immune system may be part of the answer."
Four of the victims are continuing to make a recovery after regaining consciousness and are able to talk to their families, but two other men remain in a critical condition at Northwick Park Hospital in north-west London.
Another idea proposed by Dr Glover is a new super-safe technique called "microdosing" which is just starting to attract the attention of the pharmaceutical industry.
It involves producing a blister on the patient's arm and exposing it to tiny amounts of the drug, rather than treating the whole person.
The blister fills with inflammatory fluid, containing cells whose reaction to the drug can be monitored.
The drug given to the six patients targeted a receptor molecule on the surface of white blood cells called CD28.
When CD28 is stimulated, it causes the cell to release chemical signals that play a pivotal role in the immune system. They include a chemical called interleukin-2, which helps white blood cells to recognise and destroy certain cancer cells.
In the case of the six volunteers something went wrong so that the drug triggered a "cascade" of biochemical events, leading to an overwhelming inflammatory reaction.
The drug, made by the German company TeGenero and known as TGN1412, is designed to fight rheumatoid arthritis, leukaemia and multiple sclerosis.
PA