[Daratumumab for the treatment of primary systemic amyloidosis: a multicenter retrospective analysis].

Objective: To analyze the efficacy and safety of Daratumumab for the treatment of primary AL light chain systemic amyloidosis. Methods: Twenty one patients who were diagnosed as primary AL light chain systemic amyloidosis and treated with Daratumumab from 7 centers were retrospectively analyzed. Daratumumab was administrated as first line therapy in seven patients and 14 patients with relapsed settings. Hematological response, safety and survival were analyzed. Results: All 7 patients achieved very good partial response (VGPR) or better with first-line application of daratumumab. Three patients died, and the other four achieved organ remission. Among 14 relapsed patients, 2 patients had a difference of free light chain (dFLC) less than 20 mg/L before treatment, and 9 with a dFLC of more than 50 mg/L. All patients reached partial response (PR) or better, including 4 patients with complete response (CR), 3 with VGPR and 2 with PR. The response rate was 100% in 3 patients with dFLC 20-50 mg/L at baseline. The organ remission rate was 50% in patients with heart involvement and 58.3% in patients with kidney impairment. The overall median follow-up period was 5.3 months, and 11 months in surviving patients. One patient died of severe infection and disseminated intravascular coagulation (DIC) with stable amyloidosis. One patient switched to other regimens because dFLC elevated but did not fulfill progressive disease after 2 year application. As to safety, no grade 3/4 infusion reaction developed, and grade 1 infusion reaction occurred in 3 cases during the first infusion. Lymphocytopenia was seen in 75% patients including grade 3 or more in 30% patients. Conclusion: Daratumumab is effective to eliminate serum free light chain in both newly diagnosed and relapsed patients with systemic amyloidosis.目的： 分析达雷妥尤单抗治疗原发性系统性轻链型淀粉样变的疗效及安全性。 方法： 2019年4月至2020年12月北京大学人民医院，东部战区总医院，河南省肿瘤医院等全国7个中心的21例明确诊断的原发性系统性轻链淀粉样变性且应用达雷妥尤单抗为基础的方案治疗患者进行回顾性分析。7例患者为一线应用达雷妥尤单抗，14例患者为二线及以上应用。分析血液学缓解情况、安全性及生存情况。 结果： （1）一线应用7例患者≥非常好的部分缓解（VGPR）率为7/7。3例早期死亡、脏器未获得缓解，其余4例均获得脏器缓解。（2）二线应用14例患者中2例患者治疗前血清游离轻链（dFLC）<20 mg/L。其余12例中应用前dFLC>50 mg/L者9例，均获得≥部分缓解（PR）疗效，其中完全缓解（CR）4例、VGPR3例、PR2例；应用前dFLC 20~50 mg/L之间3例，有效为3/3，即均降至10 mg/L以下。心脏受累者缓解率5/10，肾脏受累者缓解率7/12。（3）总体中位随访5.3个月，存活患者中位随访11个月，共3例患者出现死亡（2例为心源性死亡；1例出现严重感染、弥散性血管内凝血死亡），无血液学进展患者，1例患者应用后2年dFLC升高（未达进展标准）更换方案。（4）安全性：没有患者出现3/4级输液反应，共3例出现1级输液反应，均为首次输液时候出现。除1次输注治疗后死亡病例外，15/20例患者出现淋巴细胞减少，其中≥3级淋巴细胞减少为6/20。 结论： 达雷妥尤单抗是一种能够有效深度清除血清游离轻链、治疗系统性轻链淀粉样变的药物。.