REAL-MS: Observational Database Study of AHSCT and MS Therapies

Inclusion Criteria: * Diagnosis of MS according to the appropriate diagnostic criteria at the time of diagnosis; * Age ≥ 18 years old at the time of the inclusion in the study; * Treatment with AHSCT or a H-E DMT at a participating centre. Eligible H-E DMTs will include anti-CD20 monoclonal antibodies, natalizumab, alemtuzumab, cladribine, and other therapies approved by the study management group during the study period; * Availability of a minimum required baseline dataset as defined in the study case report form and data dictionary; * Availability of at least one post-baseline clinical assessment, unless the patient is included in safety analyses only; * For participation in the prospective phase of the study, capacity to provide informed consent, as judged by the investigator, and provision of written informed consent where required by applicable local regulations and ethics approvals; Exclusion Criteria: * Age \<18 years at the time of study inclusion; * Insufficient baseline data to confirm eligibility, treatment exposure, or key study variables; * No post-baseline follow-up data, unless the participant is included in safety analyses only; * Concurrent participation in an interventional randomised controlled trial where inclusion in the study would conflict with the trial protocol or compromise interpretation of study outcomes; * Lack of informed consent for prospective participation