P36 Serum immunoglobulin levels and risk of serious infections in the pivotal phase III trials of ocrelizumab in multiple sclerosis and their open-label extensions. Issue 4 (April 2020) - Derfuss, T.; Weber, M.; Hughes, R.; Eggebrecht, J.; Wang, Q.; Sauter, A.; Koendgen, H.; Hauser, S.; Bar-Or, A.; Hartung, H.P.