Today, AveXis announced that three cases of intravenous systemic treatment with AAV9-CB-SMN for spinal muscular atrophy type 1 (SMA1) have been completed. The first patient was enrolled and completed treatment on May 13 of this year, and it has been nearly five months since that date without any treatment-related adverse effects. Although the efficacy of the treatment remains to be further evaluated, as AveXis says, this represents the beginning of a new era. Of particular interest is the fact that the subjects in this clinical trial are babies just a few months old. Previously this was an absolute no-go area for clinical trials, but due to the unique nature of SMA1 disease (a serious and fatal disease in which children die within 2 years of age and for which there is no effective treatment). Faced with this fact, the FDA showed great flexibility and a spirit of case-by-case analysis and agreed to conduct clinical trials. (Starting from this year, the FDA has been very positive about gene therapy, especially AAV-based gene therapy. This clinical trial will be far-reaching because if AAV treatment is given to infants, who are the most vulnerable and prone to long-term effects, without any special adverse effects, it will fully prove the safety of AAV gene therapy and undoubtedly lay the foundation for the safety of AAV gene therapy. In the future, a large number of AAV-based gene therapy will rapidly enter the clinical trial and clinical application stage. If nothing else, gene therapy will enter an explosive growth phase in the near future, bringing new treatment options for many patients.