Haemophilia gene therapy success

A group of US researchers has achieved surprise success in a gene therapy trial for haemophilia, an inherited blood-clotting disorder. Scientists based at Beth Israel Deaconess Medical Center in Boston and the University of North Carolina originally designed the trial to test the safety of their approach, but four out of the six patients showed a significant improvement. Team leader David Roth presented the findings at the annual meeting of the American Society of Hematology, reports last week's New Scientist.

Haemophilia patients have no working copy of the gene that makes a vital blood clotting protein called factor VIII. Currently, the only treatment for the illness is regular injections of factor VIII to prevent life-threatening internal bleeding episodes. During the trial the researchers took skin cells from six patients, injected the factor VIII gene, and grew them in the laboratory. They then injected the altered cells back into the patients, one of whom did not need any additional factor VIII for three months. 'This had never happened before in his life' said Dr Roth.

The scientists did not think their approach, based on a non-viral gene delivery system, would produce enough factor VIII to have any effect. But the results show that gene therapy researchers have to keep an open mind about what might work, said Paul Monahan of the University of Carolina.