The UPSTREAM trial is a biomarker-driven umbrella trial of targeted therapies and immunotherapy for RM SCCHN (post-platinum, ECOG 0-1, measurable disease). The B1 cohort was a phase II, randomized, open-label substudy evaluating the efficacy of afatinib (orally, 40mg/day)....All responding patients had previously been treated with cetuximab, were PTEN high but none had EGFR or HER2 alterations.