Gene-targeted versus broad-spectrum therapies in ALS: comparative lessons and strategic outlook

Amyotrophic lateral sclerosis (ALS) is a relentless and fatal neurodegenerative disorder characterized by the progressive loss of motor neurons, leading to muscle weakness, paralysis, and ultimately, respiratory failure. Despite a growing understanding of its complex pathophysiology, therapeutic options remain limited. This review critically analyzes recent clinical advances by comparing two divergent strategies, including precision gene-targeted therapies for monogenic ALS subtypes and broad-spectrum agents for the wider sporadic population. While gene therapies like tofersen demonstrate clear molecular target engagement, their translation to robust clinical benefit remains a challenge. In contrast, broad-spectrum agents have faced consistent late-stage failures, often due to the disease's underlying diversity, which undermines a one-size-fits-all approach. We argue that this heterogeneity, coupled with a lack of predictive biomarkers and the difficulty of late-stage intervention, represents the core barrier to progress. The future of ALS therapeutics therefore depends on a strategic pivot toward personalized medicine. This requires prospectively stratifying patients, developing rational combination therapies, and intervening earlier in the disease course, ultimately treating ALS as a syndrome of distinct molecular diseases rather than a single entity.