BTG SIGNS DEAL WITH TRANSKARYOTIC

The British Technology Group has announced the completion of a second worldwide licensing agreement to US company Transkaryotic Therapies for rights to develop gene products for the treatment of hemophilia. The agreement covers the development of a treatment for hemophilia B using TKT's proprietary gene therapy technology with BTG's cloned human gene for Factor IX.

TKT's gene therapy offers a method of incorporating the cloned gene for Factor IX into the cells of hemophilia B sufferers, allowing the continuous in situ production of the deficient gene product. Current therapy for the condition involves the intravenous administration of Factor IX concentrates derived from human blood sources, and so carry a risk of transmission of blood-borne viruses such as HIV and hepatitis B.

TKT's approach to gene therapy does not involve the use of retroviral transmission vectors to insert the genes into target cells, so may be more likely to gain approval from regulatory authorities. The process involves taking a sample of the patient's skin and genetically-modifying the cells to produce Factor IX, whereupon they are reinjected under the skin. It is anticipated that clinical trials in this area will begin in 1993.