The Year of the Gene Therapy

    18/02/2018

    Gene therapy

    As the lunar new year dawned last week I thought about the latest scientific accomplishments that have been achieved in my field and what they mean for me as a life scientist.  Now that I am working on developing gene therapy treatments I find myself with a front row seat to possibly one of the biggest breakthroughs in human history – the eradication of genetic diseases at their source.

    In many ways 2017 was a breakthrough year for gene therapy. The FDA approved several new treatments designed to cure devastating genetic diseases.  These included Kymriah, a CAR-T cell therapy indicated for childhood B-cell lymphoblastic leukemia; Yescarta, a T cell immunotherapy for the treatment of B-cell lymphoma in adults; Imlygic, an oncolytic viral therapy that treats melanoma and Luxturna, an AAV gene therapy that corrects the mutation causing retinal dystrophy. Other genetic diseases such as sickle-cell disease and hemophilia are also seeing clinical trials come to fruition both in the US and across the world.  With the flood gates open for such treatments, this year the FDA is likely to approve even more gene therapy products.

    Gene therapy requires the use of viral vectors (adeno-associated viruses (AAV), adenoviruses, lentiviruses and gamma-retroviruses), or cationic liposomes, to deliver healthy genes to patients suffering from inherited diseases caused by mutated genes.  The idea of replacing faulty genes with functional ones in patients has been around for decades and twenty years ago it was all the rage.  However, the death of Jesse Gelsinger in 1999 while on a clinical trial for his X-linked genetic disease, put a halt to the field. It was not until a few years ago when there was a resurgence in interest for using viral vectors.  In the intervening years, many scientists have labored in the shadows improving viral vectors for better safety and efficacy, while overriding the body’s natural immune response to neutralize or (worst case scenario) to react against viruses.

    A brief history of gene therapy (Keeler et al., 2017):

    Timeline

    It is on the back of these efforts that I am able to come in today to test new viral vectors for treating diseases like cystic fibrosis.  It could take years before my current research gets approval for treatment.  In the meantime there is much work to be done – gene therapy clinical trials are now going on everywhere and there is a race between various biotech companies to get the first approval in for each disease treatment.  Here’s to hoping and expecting that 2018 brings in some extraordinary treatments.

    To help people understand this field, I want to dedicate my next few blogs to a more in-depth review of AAV as a gene delivery product and do a case study on the Luxturna treatment for blindness.

     

     

    References:

    https://www.fda.gov/BiologicsBloodVaccines/CellularGeneTherapyProducts/ApprovedProducts/default.htm

    https://www.technologyreview.com/s/609643/2017-was-the-year-of-gene-therapy-breakthroughs/

    http://www.cnbc.pt/research/department_group_show.asp?iddep=1221&idgrp=1222

    Keeler et al., Clin. Transl Sci, 2017, 10(4): 242-248: Gene Therapy 2017: Progress and Future Directions