Gene transfer using a viral vector: the future is now
In the December 9th, 2017 edition of the New England Journal of Medicine researchers from England used a adenovirus vector encoded with a wild-type factor VIII codon (AAV5-hFVIII-SQ) to inject 9 men with severe hemophilia A. One participant received a low dose, one intermediate and 7 men received a high dose infusion. All participants were followed for 52 weeks. The infusion of high dose AAV5-hFVIII-SQ was associated with sustained normalization of factor VIII activity level over a period of 1 year with stabilization of bleeding times and a profound reduction in the use of factor VIII in all 7 participants.
As you know, hemophilia is a X-linked mutation in the gene encoding coagulation factor VIII. Though exogenous factor VIII is available, its short half-life necessitates frequent infusions up to 3 times weekly. Vector-mediated gene therapy has seen success in several genetic diseases included hemophilia B. The specific challenge in hemophilia A is the large size of the coding region making this work even more exciting.
The use of gene therapy in cancer dates back many years but with only limited success. Prostate cancer as well as glioblastoma and other types of cancer have been the subject of small phase 1-2 studies. Whether used to deliver a prodrug, produce oncolysis or replace tumor suppressor genes such as p53 and the retinoblastoma gene, the developments in the field of gene therapy are beginning to explode onto the scene. The frequency of breast cancer makes it an obvious target in the future.viral vector