A Retrospective Analysis of Disease Modifying Drug Discontinuation in Patients with Multiple Sclerosis (S31.010)

To analyze patients with Multiple Sclerosis (MS) who discontinue disease modifying drugs (DMD) and experience disease activity (DA). Although several studies have investigated outcomes related to DMD discontinuation, these results remain inconclusive. Our study aims to investigate the risk of MS disease activity after drug discontinuation. This was an IRB-approved study. Retrospective analysis was conducted in patients seen at a single academic center from 2020-2023. Out of 930 patients screened, 170 (18.2%) discontinued DMD. Mean age and EDSS were 60.3 years and 3.58, respectively. Patients discontinued DMD due to multiple reasons (side effects: 32%, MD suggestion: 34%, patient preference:17%, Insurance issues: 9%, Misc: 9%). A total of 27 patients (15.8%) developed DA (all had MRI activity, 13 with relapse) after discontinuation of DMD. The number of patients developing disease activity after discontinuing a specific DMD were as follows: fingolimod 7/12 (58%), natalizumab 7/23 (30%), B-cell depleting therapy 2/14 (14%), teriflunomide/dimethyl fumarate 4/31 (13%), IFN/glatiramer acetate 5/105 (5%). Mean age was 48 (only 4 patients were > 60 years) and EDDS was 2.8 (all < or =6.5). Patients who developed disease activity after discontinuing DMD were younger (mean age 48) compared to patients who remained with no disease activity (mean age 60) and had lower average EDSS scores (2.8 vs 3.58). Patients who discontinued fingolimod and natalizumab were at higher risk of disease activity after treatment discontinuation (58% and 30%, respectively). Finally, patients > 60 years and EDSS > 6 were at the lowest risk of disease activity after discontinuation. Disclosure: Miss Karayi has nothing to disclose. Dr. Quinones-Herrero has nothing to disclose. Janice martin has nothing to disclose. Dr. Chaudhry has nothing to disclose. The institution of Dr. Cahill has received research support from Roche / Genentech. Dr. Cahill has received publishing royalties from a publication relating to health care. Dr. Rizvi has received personal compensation in the range of $500-$4,999 for serving as a Consultant for Serono Roche Bristol Myers . Dr. Rizvi has received personal compensation in the range of $5,000-$9,999 for serving as an Expert Witness for Na.