Treatment options are limited for patients with hematologic malignancies who relapse after allogeneic stem cell transplantation (allo-SCT). We conducted a pilot study to assess the tolerability and efficacy of low-dose nivolumab, a PD-1 inhibitor, as maintenance therapy after allo-SCT. Of the 4 patients enrolled in the study, all rapidly developed immune-related adverse events (irAEs); 2 patients experienced serious adverse events, including grade 4 neutropenia and grade 3 autoimmune encephalopathy. As a result of these unexpected severe toxicities, the study was closed to further enrollment. Even at low doses, nivolumab maintenance in the post allo-SCT setting can cause serious irAEs beyond graft-versus-host disease, and further studies of dosage and timing after allo-SCT are needed.

中文翻译：

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异体干细胞移植后给予Nivolumab作为维持治疗的意外毒性。

对于异基因干细胞移植（allo-SCT）后复发的血液系统恶性肿瘤患者，治疗选择有限。我们进行了一项初步研究，以评估同种SCT后低剂量的PD-1抑制剂nivolumab作为维持治疗的耐受性和疗效。在该研究的4名患者中，所有患者均迅速发展了与免疫相关的不良事件（irAEs）。2例患者发生了严重的不良事件，包括4级中性粒细胞减少和3级自身免疫性脑病。由于这些出乎意料的严重毒性，该研究无法进一步招募。即使在低剂量的情况下，异体SCT术后维持nivolumab也可能导致严重的irAE发生，而不是移植物抗宿主病，因此需要进一步研究异体SCT后的剂量和时机。