GlaxoSmithKline and UCB. EQ, SM, RK and DJC are employees of GlaxoSmithKline and own stock in GlaxoSmithKline. JP was formerly employed at Genmab and owned Genmab stocks. Patient consent Obtained. Contributors Helle Kastberg and Soren Tamer (Genmab) provided advice on study design. Peter Critchley, Shilpa Vadher and Janet Perkins (GlaxoSmithKline) provided clinical operations, data management and programming support. EQ (GlaxoSmithKline), clinical investigation leader and medical monitor of this trial, authored the manuscript. Editorial support (writing assistance, assembling tables and ﬁgures, collating author comments, grammatical editing, and referencing) was provided by Julie Taylor of Peak Biomedical Ltd, Macclesﬁeld, UK and was funded by GlaxoSmithKline. Ethics approval All participating sites received approval from national, regional, or investigational centre ethics committee or institutional review boards, as appropriate. 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