The Real-World Efficacy and Side Effects of Different Nivolumab Regimens in Japanese Patients with Advanced Melanoma: A Single-Center Retrospective Study.

: Nivolumab is a key therapy for advanced-stage melanoma; however, limited data are available from Asian populations comparing the efficacy and side effects of four dosing regimens: 3 mg/kg every 2 weeks (3mg/kgQ2W), 2 mg/kg every 3 weeks (2mg/kgQ3W), 240 mg every 2 weeks (240mgQ2W), and 480 mg every 4 weeks (480mgQ4W). This retrospective study evaluated Japanese patients with advanced melanoma treated with various nivolumab regimens to assess the impact of dosing interval and dosage on treatment efficacy and immune-related adverse events (irAEs). : We reviewed the records of 153 participants with stage IV melanoma who received nivolumab monotherapy between February 2012 and December 2024 at Shizuoka Cancer Center. Patients were categorized by nivolumab regimen, dosing interval, and dose per body weight. We then compared treatment efficacy and incidence of irAEs across groups. : No significant differences were observed in objective response rate (ORR), progression-free survival (PFS), overall survival (OS), or irAE incidence between the 240mgQ2W and 480mgQ4W groups. Similar results were observed in the 3mg/kgQ2W and 2mg/kgQ3W groups. However, participants who received nivolumab within 3 weeks exhibited a significantly higher ORR than those who received nivolumab more than 3 weeks. No significant differences were found in PFS or OS. : The administration of nivolumab at shorter intervals may provide short-term benefits in Japanese patients with advanced melanoma. However, long-term efficacy and side effects did not differ significantly across the studied nivolumab regimens.