Ionis’ Zanvastro approval for Alexander disease also signals how rare neurology programs are being structured to reach the market without commercialization partners. The FDA’s green light establishes a new reference point for disease-modifying antisense therapies in CNS disorders where treatment history has often been limited to symptom management. In parallel, analysts and company messaging suggest the approval can expand diagnostic and care pathways, including patient access support and additional real-world adoption steps beyond the pivotal efficacy signal. For the rare-disease segment, the approval adds another demonstrated mechanism to the oncology/neurology-adjacent RNA-modality playbook, reinforcing confidence in GFAP-driven biology as a clinically actionable axis.