Within the clinical trial setting, Sangamo Therapeutics will use the zinc finger nuclease technique  to introduce the gene of a missing coagulation factor into the hepatic cells of men presenting with haemophilia B. The patients will have “a new gene in their liver” by the end of treatment. The company also seeks to treat Hurler and Hunter syndromes – diseases caused by the absence of a gene involved in development, thus triggering neurological and cardiovascular problems.
The initial clinical trial phase will involve six men presenting with severe haemophilia B, each of whom will receive a different intravenous dose of the medicinal product known as SB-FIX. This contains gene-coding zinc finger nucleases and the functional gene to be incorporated. Doctors ensure that a small number of hepatocytes are modified but this low number could trigger production of the missing coagulation factor in sufficient quantities. Scientists hope that this treatment will prove to be “long-term”.
 In the autumn of 2016, SB-FIX was granted “orphan drug status” by the Food and Drug Administration (seeGenome editing: heading towards treatment for haemophilia B?).