Background Cladribine tablets (CT) improve clinical and MRI outcomes in patients with active RMS, with significant differences versus placebo after 24 weeks.

Objective Describe the design of a study to assess the onset of CT’s clinical and MRI effects in patients with active RMS.

Methods MAGNIFY-MS is a 2 year prospective Phase IV trial (including approximately 100 centres in Europe). Eligible patients will receive two years treatment with CT 3.5 mg/kg cumulative dose. Frequent MRI assessments (including lesion count, lesion volume, brain volume and MTR) will be performed at screening, baseline and 1, 2, 3, 6, 12, 15, 18 and 24 months. Various T- and B-cell subtype counts and functional profiling (eg cytokine production) will be assessed. Clinical outcomes will include changes in cognition (SDMT), disability (EDSS/KFS, 9HPT, T25FW), relapses, NEDA, NEDAP and safety at timepoints up to 24 months.

Results Aim recruit 300 patients. Primary endpoint: change in the count of combined unique active lesions at end of 6 months versus baseline. Final outcomes expected in 2021.

Conclusions MAGNIFY-MS will provide important information on the effects of CT, including early MRI changes, insights into effects on a range of disability and cognition markers, and detailed characterization of immune cell reconstitution.

Disclosure statement This study was sponsored by EMD Serono, Inc., a business of Merck KGaA, Darmstadt, Germany (in the USA), and Merck Serono SA – Geneva, an affiliate of Merck KGaA Darmstadt, Germany (ROW).