Safety
ADVERSE EVENTS
AEs were reported by 13 (50.0%) patients. Treatment‐related AEs were mainly grade 1 or 2. Five (19.2%) patients had grade 3–4 AEs and two (7.7%), serious AEs (SAEs). The most common grade 3–4 AEs were laboratory abnormalities, especially increased alanine aminotransferase (7.7%) (Table Treatment‐related adverse events of nivolumab maintenance therapy.