Natalizumab-Related Progressive Multifocal Leukoencephalopathy (PML) in Multiple Sclerosis (MS) Italian Patients: Course, Outcome and Follow-Up (P2.061)

Objective: To describe the progressive multifocal leukoencephalopathy (PML) and immune reconstitution inflammatory syndrome (IRIS) course, treatment and outcomes. Design-methods: clinical and neuroradiological data of 34 MS patients who manifested natalizumab-related PML from November 2009 to May 2015 were obtained from 25 Italian Multiple Sclerosis (MS) Centres and analyzed in the current work. Results: PML disability peak was observed at the 6th month (mean EDSS increases of 1.2 points compared to the PML outset), confirmed after 18 months follow up (mean EDSS increased 0.7 points from baseline). Higher number of CSF virus copies was related to the worse clinical course or death. 29 patients survived, 3 patients died within 6 months from the PML onset and 2 patients died within 3 years due to long term bed immobility. Lower MRI lesion widening and monofocal presentation were related to a better clinical evolution, barring the subtentorial lesions. 19/34 patients manifested IRIS and a subacute clinical worsening in the first 5 months after PML onset; 15 of them were treated with intravenous steroids with clinical improvement. Epileptic seizures were observed in 10/34 patients (29.5[percnt]), 2 of them at PML onset, 5 during IRIS and 3 after PML recovery. 2 patients were presenting with generalized tonic-clonic seizures, 1 with status epilepticus and 7 with focal attacks. Drugs showed poor efficacy during the acute phase of epilepsia, however their efficacy improved over time. Conclusions: Most of patients survived to PML but manifested a slight long term worsening of their clinical condition. Steroid treatment of IRIS might reverse the IRIS-related disability increment. Epileptic seizures were commonly observed in PML and a progressive improvement of pharmacological response can be expected during the follow-up. Disclosure: Dr. De Rossi has nothing to disclose. Dr. Cordioli has received personal compensation for activities with Genzyme and Biogen Idec. Dr. Amato has received personal compensation for activities with Biogen Idec, Merk Serono, Bayer, Novartis, Teva, Sanofi, Genzyme, Almirall. Dr. Amato has received personal compensation for activities with Biogen Idec, Merk Serono, Bayer, Novartis, Teva, Sanofi, Genzyme, Almirall. Dr. Clerico has received personal compensation for activities with Merck Serono as an advisory board member. Dr. Deotto has received personal compensation for activities with Novartis, TEVA, and Almirall Dr. De Riz has received personal compensation for activities with Merk Serono as a consultant. Dr. Scarpazza has nothing to disclose. Dr. Fusco has nothing to disclose. Dr. Ghezzi has received personal compensation for activities with Biogen Idec, Merk-Serono, Novartis, Genzyme, Teva, Serono Symposia Int Found., Novartis, and Almirall. Dr. Grimaldi has received funding for travel or speaker honoraria from Merck Serono, Biogen Idec, Sanofi-Aventis, Novartis and TEVA Pharmaceutical Industries, Inc. Dr. Grimaldi has received funding for travel or speaker honoraria from Merck Serono, Biogen Idec, Sanofi-Aventis, Novartis and TEVA Pharmaceutical Industries, Inc. Dr. Lugaresi has received personal compensation for activtiies with Bayer Healthcare, Biogen Idec, Genzyme/Sanofi, EMD Serono, Novartis, and Teva CNS. Dr. Lugaresi has received research support from Bayer Healthcare and Biogen. Dr. Moiola has received personal compensation for activities with Biogen Idec, Genzyme-Sanofi, Novartis and Merck Serono as a speaker, Dr. Perrone has received personal compensation for activities with Biogen Idec, Merk-Serono, Teva Neurosceince, Novartis, and Genzyme Corporation. Dr. Prosperini has received personal compensation for activities with Bayer Schering, Biogen Idec, Genzyme, Novartis, and Teva Neuroscience. Dr. Rezzonico has received personal compensation for activities with Biogen Idec, Merck Serono, Bayer, Teva, Novartis, Sanofi-Aventis, and Baxter. Dr. Rovaris has received personal compensation for activities with Almirall, Biogen, Genzyme-Sanofi, and Teva. Dr. Salemi has received research support from Merck Serono, Biogen-Idec, Teva Neuroscience, Novartis, Bayer Pharmaceuticals Corporation, and Sanofi-Aventis Pharmaceuticals. Dr. Salvetti has received personal compensation for activities with Sanofi-Aventis, Biogen Idec, Bayer Schering, and Merck Serono. Dr. Salvetti has received research support from the Italian Multiple Sclerosis Foundation (FISM). Dr. Santuccio has received personal compensation from Novartis and Teva for activities as a speaker. Dr. Tortorella has received personal compensation for activities with Biogen, Sanofi-Aventis, Serono and Bayer-Schering, Teva,Genzyme and Novartis as a speaker. Dr. Ruggero Capra has nothing to disclose.