Exploring Genetic Therapies Targeting Amyotrophic Lateral Sclerosis in Animal Models: A Systematic Review and Meta-Analysis.
BACKGROUND: Amyotrophic lateral sclerosis (ALS) is a rare, neurodegenerative disease, for which there is currently no known cure. ALS primarily affects motor neurons, with rapid deterioration, meaning symptoms develop quickly, from problems with speech and muscle weakness to breathing issues and paralysis. This systematic review aimed to explore the preclinical efficacy of various genetic therapies used to target ALS using in vivo rodent models. METHODS: In vivo studies of genetic therapies targeting ALS and its symptoms published between January 2015 and December 2025 were included in this review. The following databases were used: Web of Science, Scopus and PubMed. The primary outcome investigated was the total number of motor neurons, with secondary outcomes of rodent survival and muscle function by observing rotarod performance also being analysed. The SYRCLE tool was used to assess risk of bias in included studies. RESULTS: Of the 451 studies identified by searching the databases, 53 studies were found to be eligible for this systematic review. The articles were divided into subcategories depending on the gene target of each therapy. Meta-analysis of outcomes within appropriate studies showed significant improvements for the majority of selected outcomes (p < 0.05), favouring genetic therapy intervention. CONCLUSIONS: Results suggest that genetic therapies in rodent models targeting ALS are effective. However, due to a high risk of bias in preclinical studies, further high-quality studies are warranted to support this conclusion and onward translation into the clinic.