January 9, 2019

Haemophilia gene therapy: we are not alone

The number of trials of cell and gene therapy carried out in the UK has increased by more than one-third in the past year, according to the Cell and Gene Therapy Catapult (https://ct.catapult.org.uk), a London-based development agency that provides support for innovators in the field.

The Catapult’s latest statistics show there are 85 clinical trials and 875 preclinical research projects in cell and gene therapies now underway, with gene therapies accounting for 73% of studies. Most clinical trials are in the recruitment phase and about 80% are Phase I or Phase II trials.

Haematology accounts for 17% of trials, second only to oncology (29%) and surpassing ophthalmology (14%). In the 29 gene therapy trials that are being carried out in humans or live subjects, 86% use the adeno-associated virus vector (AAV) that has been trialled for haemophilia. There are three trials of gene editing (a procedure by which the patient’s mutated gene is altered), one of which is of FIX for haemophilia B.

The Cell and Gene Therapy Catapult maintains a database of gene therapy trials which is accessible online at https://ct.catapult.org.uk/sites/default/files/publication/Clinical%20Trials%20Database%202018.pdf.

Researchers from Singapore recently published a review of technologies for gene editing; the full text is available free online (Int J Mol Sci 2018 Sept 12;19(9). doi: 10.3390/ijms19092721).

Meanwhile, US-based Sangamo Therapeutics has announced the first treatment of a patient in its Phase I/II trial of SB-FIX, its gene editing technology for haemophilia B. This strategy uses a zinc finger nuclease to snip the DNA molecule and introduce a new functional gene. It therefore offers a permanent alteration of the mutated gene responsible for haemophilia that the patient will pass on to his children. The trial is being carried out in five US centres and in Glasgow, Birmingham and London, where potential participants are now being screened.