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We thank all patients, their families and all investigators involved in the PRIME and PEAK studies. Medical writing support (including development of a draft outline and subsequent drafts in consultation with the authors, assembling tables and figures, collating author comments, copyediting, fact checking and referencing) was provided by Louisa Lyon, DPhil and Louise Niven, DPhil at Aspire Scientific (Bollington, UK), and funded by Amgen (Europe) GmbH (Zug, Switzerland).

Author information


  1. Department of Oncology, Antwerp University Hospital, Wilrijkstraat 10, 2650, Edegem, Belgium

    • Marc Peeters
    •  & Timothy Price
  2. Queen Elizabeth Hospital/University of Adelaide, 28 Woodville Rd, Woodville South, SA, 5011, Australia

    • Timothy Price
  3. Sorbonne Paris Cité, Paris Descartes University, Georges Pompidou European Hospital, 20 Rue Leblanc, 75015, Paris, France

    • Julien Taieb
  4. Klinikum Esslingen, Cancer Center Esslingen, Hirschlandstraße 97, 73730, Esslingen am Neckar, Germany

    • Michael Geissler
  5. Hospital Universitario Marqués de Valdecilla, Av. Valdecilla, 25, 39008, Santander, Spain

    • Fernando Rivera
  6. Service d’Oncologie-Hématologie, Grand Hôpital de Charleroi, Avenue du Centenaire 73, 6061, Charleroi, Belgium

    • Jean-Luc Canon
  7. Department of Medical Oncology, Ioannina University Hospital, Leof. Stavrou Niarchou, 455 00, Ioannina, Greece

    • George Pentheroudakis
  8. Biostatistics, Amgen Ltd, Sanderson Road, Uxbridge, UB8 1DH, UK

    • Reija Koukakis
  9. European Medical, Amgen (Europe) GmbH, Dammstrasse 23, 6300, Zug, Switzerland

    • Peter Burdon
  10. Dipartimento di Oncologia e Emato-Oncologia, Università degli Studi di Milano, Niguarda Cancer Center, Grande Ospedale Metropolitano Niguarda, Piazza dell’Ospedale Maggiore, 3, 20162, Milan, Italy

    • Salvatore Siena


R.K. and P.B. were responsible for conception and design of the analyses. T.P. and J.-L.C. contributed to the design of the analyses. M.P., T.P., J.T., F.R., J.-L.C. and S.S. contributed to patient data collection. RK performed the data analyses. All authors contributed to the interpretation of the data, the preparation and revision of the manuscript, and approved the final version.

Competing interests

M.P. has received research funding from Amgen, Roche and Sirtex, and honoraria from Amgen, Merck Serono, Roche, Sanofi Aventis, Servier and Sirtex. T.P. has acted on advisory boards for Amgen, Merck Serono and Roche, and has received travel support from Amgen. J.T. has acted in consultancy and/or advisory roles for, and received honoraria from Amgen, Baxalta, Celgene, Eli Lilly, Merck, Roche, Sanofi, Servier and Sirtex. Michael Geissler has received research funding and acted in consultancy/advisory roles for Amgen, Bayer, Merck, Roche and Sanofi. F.R. has received research funding from and/or acted on advisory boards for Amgen, Bayer, Celgene, Eli Lilly, Merck Serono, Merck Sharp & Dohme, Roche, Servier and Sanofi. J.-L.C. is a consultant/advisor for Amgen and Roche and has received institutional funding from Amgen, Novartis and Roche. G.P. has received research funding and advisory consulting fees from Amgen, Astra Zeneca, Boehringer, Bristol Myers Squibb, Lilly, Merck, MSD and Roche. R.K. is an employee of Amgen Ltd and owns restricted shares in Amgen. P.B. is an employee of Amgen (Europe) GmbH and owns shares in Amgen. S.S. is a member of advisory boards for Amgen, Bayer, Celgene, Eli Lilly, Ignyta, Merck, Merrimack, Novartis, Roche and Sanofi.

Consent to participate

All patients provided informed consent.

Ethics approval

The PRIME and PEAK studies were conducted in accordance with the Declaration of Helsinki. Study protocols were approved by an independent ethics committee at each study center.


The PRIME (NCT00364013) and PEAK (NCT00819780) studies were supported by Amgen Inc.

Corresponding author

Correspondence to Marc Peeters.

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