Highlights from International Neuroscience Meetings

Natalizumab discontinuation after the 24th Course: Which Is Way? The TY-STOP Study Marinella Clerico,1 Stefania De Mercanti,1 Federico Piazza,1 Dario Gned,1 Vincenzo Brescia Morra,2 Roberta Lanzillo,2 Luca Amato,2 Mario Quarantelli,2 Angelo Ghezzi,3 Anna Bianchi,3 Damiano Baroncini,3 Marco Gibbin,4 Joseph Vargas,4 Giuseppe Salemi,5 Sabrina Realmuto,5 Maria Teresa Ferrò,6 Francesca Vitetta,7 Patrizia Sola,7 Damiano Paolicelli,8 Maria Trojano,8 Luca Durelli.4 1University of Torino, Orbassano, 2Università Federico II, Napoli, 3Centro Sclerosi Multipla, Ospedale Sant’Antonio Abate, Gallarate, 4University of Torino Azienda Ospedaliera Universitaria San Luigi Gonzaga, Orbassano, 5Università degli Studi di Palermo, Palermo, 6Osp. Maggiore Di Crema, Crema, 7Ospedale Civile Sant’Agostino Estense Universita’ di Modena e Reggio Emilia, Modena, 8Policlinico di Bari, Bari, Italy. Objective: Comparison of disease activity (percentage of patients with relapses and/or MRI activity) between the year before and after Natalizumab discontinuation. Background: Natalizumab may cause progressive multifocal leukoencephalopathy (PML). According to risk stratification after the 24th course, patients can decide whether to continue Natalizumab. Design/Methods: Multicenter prospective observational study, involving 7 centers, 88 patients enrolled (56 female; average age 40) with relapsing-remitting multiple sclerosis (RRMS) clinically and radiologically stable, treated with 24 Natalizumab administrations. The study provides 6 visits at month (M) 0, 1, 3, 6, 9, 12, and 3 brain MRI at M0, M6, M12. Enrolled patients reached the following timepoints: 80 patients M3, 68 patients M6, 55 patients M9, 31 patients M12. We calculated the percentage of relapses and MRI activity stratified by therapy. Results: The percentage of patients with relapses during the year after Natalizumab discontinuation was 35.6%: 3.7% among patients continuing Natalizumab, 17.8% among those who started other immunomodulatory or immunosuppressive therapy, and 16.7% among patients without therapy. The percentage of patients with MRI activity after the 24th Natalizumab course was 34.8%: 3.7% among patients continuing Natalizumab, 20.5% among those who started other immunomodulatory or immunosuppressive therapy, and 21.4% among patients without therapy. Evaluation of HR with relative 95% CI for relapses, EDSS score >3, MRI activity. Data show a protective effect of therapy with Natalizumab versus no therapy on MRI activity (HR 0.81; 95% CI 0.68-0.96; p=0.015). The average of relapses and MRI activity is similar in those patients who discontinued any therapy and in those who started a first line therapy. Conclusions: Our data show a protective The 65th Annual Meeting of the American Academy of Neurology San Diego, California, USA,