Study duration:~Screening period: up to 56 days~Transition period between last sutimlimab dose and first dose of BIVV020 (for participants who were previously receiving sutimlimab): 14 days, included as part of the 56-day Screening period Treatment duration: Minimum 52 weeks~Visit frequency:~Day 1~Day 4~Weeks 1 to 6: Weekly~Weeks 7 to 12: Every other week~Weeks 13 to 24: Every 4 weeks~Weeks 25+: At least every 8 weeks~End of Study visit: 22 weeks after the last dose of BIVV020
Primary Objective:~- To evaluate the effect of BIVV020 on the durability of platelet response in participants with persistent/chronic immune thrombocytopenia (ITP)~Secondary Objectives:~To assess the safety and tolerability of BIVV020~To assess the pharmacokinetics of BIVV020~To assess the response rate of treatment with BIVV020~To assess the time to response~To assess the effect of treatment with BIVV020 on the requirement for rescue ITP therapy~To assess the immunogenicity of BIVV020