A phase Ib randomized multicenter trial of isolated hepatic perfusion in combination with ipilimumab and nivolumab for uveal melanoma metastases (SCANDIUM II trial)

Background: Uveal melanoma (UM) is a rare malignancy where 50% of patients develop metastatic disease primarily affecting the liver. Approximately 40% of patients with metastatic UM respond to one-time isolated hepatic perfusion (IHP) with high -dose melphalan. This phase I trial investigates the safety and clinical ef fi cacy of IHP combined with ipilimumab (IPI) and nivolumab (NIVO). Patients and methods: Immunotherapy-na & iuml;ve patients were randomized in this phase I trial to receive either IHP followed by IPI 3 mg/kg and NIVO 1 mg/kg (IPI3/NIVO1) for four cycles (post -operative arm), or one cycle of preoperative IPI3/NIVO1, IHP and then three cycles of IPI3/NIVO1 (pre-post-operative arm), followed by maintenance therapy with NIVO 480 mg for 1 year. Results: Eighteen patients were enrolled and randomized. Three patients did not undergo IHP as planned. In total, 11/ 18 patients (6 in the post -operative arm and 5 in the pre-post-operative arm) did not complete the planned four cycles of IPI3/NIVO1. Toxicity to IHP was similar in both groups, but the number of immune-related adverse events (AEs) was higher in the pre-post-operative arm. Among assessable patients, overall response rate was 57% in the post -operative arm (4/7) and 22% in the pre-post-operative arm (2/9). Conclusions: Combination therapy with IHP and IPI3/NIVO1 was associated with severe AEs. The efficacy of this combination is encouraging with high response rates. One cycle of preoperative IPI/NIVO before IHP did not show potential benefits in terms of safety or efficacy.