Gene Therapy – a new class of medicine

Hildegard Büning 1,2,3

1 Institute of Experimental Hematology, Hannover Medical School, Hannover, Germany

2 REBIRTH – Center for Translational Regenerative Medicine, Hannover Medical School, Hannover, Germany

3 German Center for Infection Research (DZIF), partner site Hannover

It is estimated that word-wide more than 300 million people, approximately half of them children, are affected by genetic diseases.1 For many of these diseases no effective treatment option is available. In response, the concept of gene therapy was introduced. Due to technological limitations its initial aim focused on adding a missing gene, or on replacing or counteracting the activity of a defective gene. With the rise of genome editing, gene therapy is entering a new stage in which now a repair of the underlying genetic defect can be envisioned. While numerous efforts world-wide are ongoing to improve current gene therapy strategies, gene therapy itself has reached the clinic as indicated by the so far 15 gene therapy drugs which have obtained market approval by the European Medicines Agencies (EMA). Five of these drugs target cancer with four of them employing autologous T lymphocytes equipped with a chimeric antigen receptor (CAR) as powerful weapon in cancer immunotherapy, revealing that the concept of gene therapy was expanded far beyond its initial focus. Also, the area of vaccine development greatly benefited from gene therapy since tools and technologies are in use which were initially developed in the context of gene therapy. However, further improvements are required. This concerns for example efficacy and safety of gene delivery. Regarding the latter, my talk will use the adeno-associated virus (AAV) vector system as example to discuss current strategies. In addition, besides providing an overview on the basic concept of gene therapy and its current status, this talk is intended to introduce possible future directions and to share thoughts on what is required to make this new class of medicine indeed a clinical reality.

1Goswami R, Subramanian G, Silayeva L, et al. Gene Therapy Leaves a Vicious Cycle. Front Oncol 2019; 9: 297