[1] Hosp Ramon y Cajal IRYCIS, E-28034 Madrid, Spain
[2] Hosp Ramon y Cajal IRYCIS, Clin Trial Unit, E-28034 Madrid, Spain
[3] Merck Sharp & Dohme Ltd, Med Affairs, Madrid, Spain
[4] Hosp Badalona Germans Trias & Pujol, Lluita Sida Fdn, Badalona, Spain