LONDON - Oxford BioMedica plc said it has made significant advances in the delivery of genes to the brain and other part of the nervous system using its LentiVector vectors.

The company said it has shown high gene transfer efficiency, with a good safety profile and long-term gene expression. In particular, there was no detectable adverse inflammatory response, an essential requirement for central nervous system gene therapy vectors.

Nick Mazarakis, head of neurobiology, said, "The efficiency and reliability of this system is such that we can contemplate developing a wide range of products for neurological disease." Apart from demonstrating a high level of delivery of marker genes, reporter genes have been shown to function for several months with no drop in levels of gene expression and no adverse side effects.

By engineering the LentiVector's surface molecules it is possible to target genes to different types of neurons in the brain.

Oxford BioMedica, based in Oxford, UK, is developing the vector for the treatment of Parkinson's disease. CEO Alan Kingsman said the company would now start programs in other chronic CNS diseases and in treating spinal injuries. "We can also use the technology to identify new genes that are mechanistically linked to neurodegenerative diseases."

The company also will be using the technology to generate short-term revenue by offering a service for target validation in the treatment of CNS diseases.

LentiVector is based on the Equine Infectious Anemia virus (EIAV), which has been engineered so that it cannot transfer any viral genes to the patient. This, coupled with the fact that EIAV in its natural state does not cause disease in man, is said to give this vector one of the best safety profiles in the gene therapy field.

The main advantage of lentiviral vectors over their retroviral counterparts is the ability to function in non-dividing cells, or cells that are dividing slowly. This is a feature of many clinically important tissues, including the CNS.