‘Doctor, can I stop my medicine?’ Analysis of disease course after stopping disease-modifying therapy in stable MS patients (P5.192)

OBJECTIVE: To investigate disability progression, relapse rates and treatment restart patterns in previously stable MS patients who discontinued disease-modifying therapy (DMT). BACKGROUND: There is paucity of data on MS course after DMT discontinuation. MSBase, a 30,000-patient strong global, observational MS registry, provides a unique opportunity for such a study. DESIGN/METHODS: We included patients who, at the time of DMT discontinuation, were aged 蠅40 years; had no relapses and a stable EDSS for 蠅5 years; were on DMT continuously for 蠅3 years; and, after stopping DMT, were followed for 蠅3 years. Predictors of DMT restart and time to 3-month 1 EDSS step (1.5 EDSS steps for baseline EDSS 0, 0.5 for baseline EDSS 6-6.5) confirmed progression were analysed using Cox proportional hazards regression. Hazard proportionality was assessed through analysis of scaled Schoenfeld residuals. RESULTS: 198 (65.4[percnt]) of 303 eligible patients restarted DMT following discontinuation after a median (IQR) of 1.0 month (0, 12.0). The rate of restarting DMT decreased by 25[percnt] for every 10 year increase in age (HR 0.75, 95[percnt] CI 0.57, 0.98), and by 16[percnt] for every 1-point EDSS increase (HR 0.84, 95[percnt] CI 0.78, 0.91). Gender, age at disease onset, history of subsequent relapse and identity of DMT were not associated with rate of DMT restart. There was a 46[percnt] reduction in the rate of subsequent three-month confirmed disability progression in patients who restarted DMT v. those who did not (HR 0.54, 95[percnt] CI 0.31, 0.93, after adjusting for age and baseline EDSS). CONCLUSIONS: We observed high rates of DMT restart in our cohort of stable, older MS patients who discontinued DMT. Younger age and lower EDSS predicted increased rate of restart. DMT restart was associated with reduced rates of disability progression. Analyses of relapse rates and new lesion formation in DMT restarters and non-restarters will be presented. Disclosure: Dr. Kister has nothing to disclose. Dr. Spelman has received personal compensation for activities with Biogen Idec as a speaker. Dr. Duquette has received personal compensation for activities with Berlex, Biogen Idec, Serono, Novartis, and Teva Neuroscience. Dr. Girard has received personal compensation for activities with Biogen Idec, Teva Canada Innovation, Novartis, and EMD Serono as an advisory board member. Dr. Lechner-Scott has received personal compensation for activities with Biogen Idec, Bayer Pharmaceuticals Corp., EDM Serono, and Sanofi-Aventis Pharmaceuticals as a consultant and/or speaker. Dr. Grand9Maison has nothing to disclose. Dr. Slee has nothing to disclose. Dr. Hodgkinson has received personal compensation for activities with Biogen Idec, Novartis and Bayer Pharmaceuticals Corporation as an advisory board member. Dr. Lugaresi has received personal compensation for activities with Bayer Schering, Biogen Idec, Merck Serono, Genzyme, Sanofi-Aventis Pharmaceuticals, and Teva Neuroscience. Dr. Edite Rio has nothing to disclose. Dr. Trojano has received personal compensation for activities with Sanofi-Aventis Pharmaceuticals, Inc., Biogen Idec, Novartis and Bayer Schering Pharma as a consultant and/or speaker. Dr. Butzkueven has received personal compensation for activities with Novartis, Merck Serono, and Biogen Idec as a consultant and/or advisor. Dr. Herbert has received personal compensation for activities with Biogen Idec, Teva, EDM Serono, and Bayer Pharmaceuticals as a consultant.