Gene therapy death link can't be ruled out, say experts

A panel of experts assembled to investigate the death of an Illinois woman, who died unexpectedly after receiving an experimental gene therapy, last week concluded that there was insufficient evidence to suggest the therapy was directly responsible. The death of 36-year-old Jolee Mohr, who was being treated for mild arthritis, does however raise further questions over the potential indirect effects of the gene therapy on her immune system and the conditions under which she was recruited onto the trial.

Dr Howard Fedroff of Georgetown University Medical Centre, chairman on the Recombinant DNA Advisory Committee who reviewed the case, said that the primary cause of death was likely to be a fungal infection - Histoplasma capsulatum - common in the Mississippi and Ohio River valleys. He said: 'We can't to 100 per cent certainty exclude the vector but as it was presented, the data suggest that it is unlikely to be playing a role'.

Despite this verdict, the committee were unable to offer bereaved husband Rob Mohr a satisfactory answer to the question 'would my wife be alive today if she hadn't participated in this study?', stating only that the panel would 'reserve judgement' until all the data has been collated in preparation for the next meeting in December.

The gene therapy given to Mrs Mohr was intended to produce an anti-inflammatory protein equivalent to 'Enbrel', a commonly used arthritis drug causing localised immune system suppression. Yet the finding that traces of the gene therapy had spread to Mrs Mohr's spleen and liver raises the possibility that the protein was produced outside the knee joint where it was injected, allowing the usually mild fungal infection to overwhelm Mrs Mohr's immune system.

According to the New York Times, H. Stewart Parker, president of Targeted Genetics, the Seattle based Biotechnology Company who ran the trial, said after the meeting that the tiny levels of gene therapy found in the liver and spleen support the company's view that the therapy should not be held responsible.

One judgement on which the whole committee agreed was that the way in which Mrs Mohr was recruited on to the trial, although not strictly unlawful, may not have furnished the proper conditions for informed decision making. A dismayed Mr Mohr said the fact that his wife - only mildly affected by arthritis - should have been recruited onto a trial of this nature by her own doctor was 'still beyond my belief'.