The study was sponsored by Eisai Inc., NJ, USA and Merck Sharp & Dohme Corp., a subsidiary of Merck & Co., Inc., NJ, USA.

N Gaspar, Q Campbell-Hewson and F Bautista have nothing to disclose. J Huang is an employee of Eisai Inc. CE Okpara is an employee of Eisai Ltd.

The authors have no other relevant affiliations or financial involvement with any organization or entity with a financial interest in or financial conflict with the subject matter or materials discussed in the manuscript apart from those disclosed.

Medical writing support was provided by HA Mitchell of Oxford PharmaGenesis Inc., PA, USA, and was funded by Eisai Inc. and Merck Sharp & Dohme Corp., a subsidiary of Merck & Co., Inc.