The Phase 3 trial conducted by Mayo Clinic aimed to evaluate the efficacy of IGF-I in slowing the progression of amyotrophic lateral sclerosis (ALS). With an enrollment of 330 participants across 20 medical centers, the study's completion in December 2007 and subsequent publication of results in 2009 indicated that IGF-I did not demonstrate significant benefits over placebo in terms of muscle strength or survival without tracheostomy. The failure to show efficacy may limit the commercial viability of IGF-I as a treatment for ALS, a market characterized by high unmet need but also significant competition from other investigational therapies. Companies focusing on ALS treatments may need to reassess their strategies in light of these findings, particularly in relation to IGF-I's role in neuroprotection and muscle regeneration.