In May 2025, the International Advisory Committee on Clinical Trials in Multiple Sclerosis (MS) — co-sponsored by the National MS Society and ECTRIMS — convened a pivotal meeting in Dublin to discuss a topic that could reshape the landscape of MS care and research: the revision of MS course descriptors.
The Committee, known for its leadership in shaping the way MS is classified and studied, originally defined the widely used MS course descriptors in 1996, revised them in 2013, and provided further clarification in 2020. These descriptors have been essential for clinical trials, diagnosis, and patient communication. However, as our understanding of MS has grown, so too has the need to refine the way we describe the disease.
This year’s meeting brought together different stakeholders — from investigators and clinicians, to industry representatives, people affected by MS, and other key voices in the field. The discussion was rooted in a 2023 call by the Committee to move from a clinically based definition of MS progression to one that is biologically based.
The consensus was clear: an update to the course descriptors is needed, reflecting our improved knowledge about biological mechanisms of MS, the ability to make earlier diagnoses than ever before, and the desire to better communicate with people living with MS. There is a shared sense of urgency among the Committee and the broader MS community. As research continues to uncover the biological underpinnings of MS, the tools we use to describe and track the disease must evolve alongside it.
The course descriptors need to reflect more accurately people’s real experiences with the disease. The Committee, ECTRIMS and the National MS Society are committed to driving the development of revised biologically based course descriptors that better serve people affected by MS around the globe.
The path forward
The co-sponsors of the International Advisory Committee for Clinical Trials in MS – The National MS Society and ECTRIMS – will be engaging key interest-holders, including neurologists, investigators, clinicians, regulators, industry, and people affected by MS to work together to determine the best framework and nomenclature that truly reflects the biology and experience of this disease. There will be opportunities for interest-holders to contribute and participate as this important work progresses – ensuring that the updated course descriptors are not only scientifically grounded, but also informed by those most impacted by MS.