Neuromyelitis Optica (NMO) is a neuroinflammatory disease related to multiple sclerosis (MS). It affects young subjects and causes a lot of handicap without treatment. Thus, aggressive treatments are frequently introduced early in the life of patients and maintained over the long term. A long duration of treatment exposes to iatrogenism. Therapeutic de-escalation trials in MS or other autoimmune diseases show rebound phenomena. In the NMO, there are no published data on the tolerance of desescalations to guide such strategies.

Inclusion criteria:

• Major patients who have received long-term treatment for NMO
• Patients with a prospectively diagnosed NMO using the 2015 NMO classification criteria (IPND)
• Patients who retrospectively meet the classification criteria of the 2015 NMO (IPND)
• Patients who have not expressed their opposition, after information, to the reuse of their data for research purposes.

Exclusion criteria:

• Patient who expressed his opposition to participating in the study
• Lack of data on the assay of anti-AQP4 and anti-MOG antibodies
• Less than a year of taking a second-line treatment before the relay
• End of follow-up <1 year following the transfer, this therefore includes patients whose transfer took place less than one year before the date of data extraction

Major patients who have received long-term treatment for NMO and with a prospectively diagnosed NMO using the 2015 NMO classification criteria (IPND)