On January 21, 2019, the Opposition Division of the European Patent Office determined, following multi-party opposition proceedings, to revoke European patent No. 2359834, which relates to the formulation of SOLIRIS® (eculizumab). While we are disappointed with this decision, we intend to appeal pending receipt and review of the written decision. While an appeal is pending at the European Patent Office, the claims in the originally granted patent remain effective and enforceable. In addition, we continue to pursue additional European patent filings in support of SOLIRIS, including Composition of Matter and Method of Use patents.