Researchers at the University of Florida (UF) Genetics Institute are developing the US's first benchmark supply of a gene therapy treatment, in an effort to standardise safety data from different gene therapy experiments. The scientists have developed a batch of adeno-associated virus (AAV), a type of gene delivery system (vector) used to carry therapeutic genes to body tissues affected by disease.
The UF standardised batch of AAV will be stored at a national repository, so that scientists carrying out human gene therapy trials can request a sample to compare with their own AAV stocks. 'From what we know, the potential safety concerns of gene therapy come not from the insertion of the genes themselves, but from the vector used to carry them into the cells' said Dr Terence R Flotte, interim director of the institute. He added that until there was a way of pooling information from different studies, it would not be possible to find out if a particular concentration of vector resulted in side effects.
Dr Flotte suspects that if there had been a standard batch of adenovirus (the vector used for the trial in which 18-year-old Jesse Gelsinger died last year), its potential for adverse effects might have been recognised earlier. The reference stock of AAV is likely to become available to US researchers within the next six months.
The family of Jesse Gelsinger is suing the research team involved in the gene therapy trial, including the ethicist who offered moral advice on the project. The lawsuit also names the biotech firm Genovo Inc, founded by research team leader James Wilson.