Safety of Natalizumab infusion in multiple sclerosis patients during active SARS-CoV-2 infection

: COVID-19 pandemic represented a challenge in the management of treatments for Multiple Sclerosis (MS), such as Natalizumab (NTZ). NTZ interferes with the homing of lymphocytes into the central nervous system, reducing immune surveillance against opportunistic infection. Although NTZ efficacy starts to decline 8 weeks after the last infusion, increasing the risk of disease reactivation, evidence is lacking on the safety of reinfusion during active SARS-CoV-2 infection. We report clinical outcomes of 18 pwMS receiving NTZ retreatment during confirmed SARS-CoV-2 infection. No worsening of infection or recovery delay was observed. Our data supports the safety of NTZ redosing in these circumstances.