I. Assess efficacy of BGJ398 in relation to specific genetic aberrations in HPV (+) and HPV (-) FGFR altered HNSCC (i.e. FGFR3-transforming, acidic, coiled-coil-containing protein 3 [TACC3] translocation, FGFR1 high copy number/amplification, FGFR2 mutation, FGFR3 mutation).