Ionis Pharmaceuticals reported positive pivotal Phase 3 trial results for zilganersen, an antisense oligonucleotide for Alexander disease, a rare and fatal neurogenetic disorder with no prior approved treatments. The drug demonstrated significant improvements in mobility measures compared to control, signaling a disease-modifying effect. Ionis plans to submit an FDA New Drug Application in early 2026. This milestone represents a significant advancement for rare neurological diseases and highlights Ionis’s independent drug development capabilities.