Medical research and clinical trials are carried out by health professionals whose training and everyday work is focused on the care of patients.
This work is regulated by laws and codes of conduct and is approved by local research ethics committees whose purpose is to protect the interests of people taking part in the research.
Generally clinical trials are safe, but sometimes things go wrong.
The Northwick Park tragedy
In March 2006, six men had severe and life-threatening reactions during a clinical trial. They were in a private research unit in north-west London in a trial for an experimental treatment that might have been developed to treat leukaemia or rheumatoid arthritis.
The trial was the first time that the treatment, TGN1412, had been used in people (a 'first in man' trial). All previous research on TGN1412 had been in animals.
The men had serious symptoms, including vital organ failure, fever and low blood pressure. They had to be treated in the intensive care unit at the NHS Northwick Park Hospital in Middlesex. The men survived, but their health was permanently damaged.
A detailed investigation into what went wrong recommended many changes to the way 'first in man' trials are carried out. Those recommendations have now been put into practice.
What happened to the six men in the trial was widely reported on TV and radio and in the newspapers.
What happened was shocking but is highly unusual in research. Nothing of the same scale has been reported before or since.
All 'first in man' studies, particularly those that use new types of treatment with possibly unpredictable side effects, are now carried out much more cautiously.
With research carried out in the NHS, researchers are likely to have a good idea of possible benefits and side effects of treatment. Researchers have to make the medical background clear and describe details of any new treatments or other interventions being carried out.
More information
Expert report on ‘first in man’ trials