Towards a biologically informed description of multiple sclerosis disease course - a roadmap for transition.

Contemporary management of multiple sclerosis is based on the clinical course descriptors of relapsing-remitting, secondary progressive and primary progressive. However, recognition is growing in the field that these clinical course descriptors do not capture the full disease spectrum of multiple sclerosis or reflect the underlying biological mechanisms of disease, and that biologically informed course descriptors are needed. In this Roadmap, participants in an International Advisory Committee on Clinical Trials in Multiple Sclerosis workshop discuss the problems with the existing course descriptors, highlight considerations for developing new course descriptors and propose a roadmap for transitioning towards a more dynamic, biologically informed description of the multiple sclerosis disease course.