AAV9 Vector: a Novel modality in gene therapy for spinal muscular atrophy

• Published in: Gene therapy Vol. 26; no. 7-8; pp. 287 - 295
• Main Authors: Pattali, Rithu, Mou, Yongchao, Li, Xue-Jun
• Format: Journal Article
• Language: English
• Published: London Nature Publishing Group UK 01-08-2019; Nature Publishing Group
• Subjects: 13; 14; 38; 42; 42/44; 631/378/1687; 64/60; 692/699/375; 96/100; Animals; Biomedical and Life Sciences; Biomedicine; Brain stem; Cell Biology; Dependovirus - genetics; Dependovirus - metabolism; Diagnosis; Gene Expression; Gene Therapy; Genetic Therapy - adverse effects; Genetic Therapy - methods; Human Genetics; Humans; Immune response; Infant mortality; Motor neurons; Muscular Atrophy, Spinal - therapy; Nanotechnology; Neuromuscular diseases; Quality of life; Review Article; SMN protein; Spinal cord; Spinal muscular atrophy; Survival of Motor Neuron 1 Protein - genetics; Survival of Motor Neuron 1 Protein - metabolism; Transgenes; Tropism
• ISSN: 0969-7128; 1476-5462
• DOI: 10.1038/s41434-019-0085-4

Spinal muscular atrophy (SMA), the leading genetic cause of infant mortality, is characterized by the deterioration of alpha motor neurons in the brainstem and spinal cord. Currently, there is no cure for SMA, which calls for an urgent need to explore affordable and effective therapies and to maximize patients’ independence and quality of life. Adeno-associated virus (AAV) vector, one of the most promising and well-investigated vehicles for delivering transgenes, is a compelling candidate for gene therapy. Some of the hallmarks of AAVs are their nonpathogenicity, inability to incur an immune response, potential to achieve robust transgene expression, and varied tropism for several tissues of the body. Recently, these features were harnessed in a clinical trial conducted by AveXis in SMA patients, where AAV9 was employed as a vehicle for one-time administration of the SMN gene, the causative gene in SMA. The trial demonstrated remarkable improvements in motor milestones and rates of survival in the patients. This review focuses on the advent of SMA gene therapy and summarizes different preclinical studies that were conducted leading up to the AAV9–SMA trial in SMA patients.