阿仑珠单抗
美国国立卫生研究院的前瞻性试验已对阿仑珠单抗(一种人源化抗 CD52,IgG1 单克隆抗体)治疗难治性 AA 进行了评估。在欧洲,欧洲血液和骨髓移植组 (EBMT) 对其在自身免疫性血球减少(特别是自身免疫性中性粒细胞减少症)患者中的疗效报告进行了回顾性研究。EBMT 关于使用皮下注射阿仑珠单抗的初步数据表明,它可能对治疗免疫介导骨髓衰竭综合征患者有效。[45]Risitano AM, Selleri C, Serio B, et al; Working Party Severe Aplastic Anaemia (WPSAA) of the European Group for Blood and Marrow Transplantation (EBMT). Alemtuzumab is safe and effective as immunosuppressive treatment for aplastic anaemia and single-lineage marrow failure: a pilot study and a survey from the EBMT WPSAA. Br J Haematol. 2010;148:791-796.http://www.ncbi.nlm.nih.gov/pubmed/19995389?tool=bestpractice.com感染并发症,特别是病毒相关的感染,是这种形式治疗的主要并发症。尽管接受初始治疗患者的结果不太理想,但 NIH 数据显示该疗法对难治性和复发性疾病的应答率分别为 37% 和 56%。[37]Scheinberg P, Nunez O, Weinstein B, et al. Activity of alemtuzumab monotherapy in treatment-naive, relapsed, and refractory severe acquired aplastic anemia. Blood. 2012;119:345-354.http://bloodjournal.org/content/119/2/345.longhttp://www.ncbi.nlm.nih.gov/pubmed/22067384?tool=bestpractice.com
大剂量环磷酰胺 (HDC)
一家中心建议使用无干细胞支持的 HDC 治疗新近诊断为 AA 的患者。[46]Brodsky RA, Sensenbrenner LL, Smith BD, et al. Durable treatment-free remission after high-dose cyclophosphamide therapy for previously untreated severe aplastic anemia. Ann Intern Med. 2001;135:477-483.http://www.ncbi.nlm.nih.gov/pubmed/11578150?tool=bestpractice.com[47]Brodsky RA, Sensenbrenner LL, Jones RJ. Complete remission in severe aplastic anemia after high-dose cyclophosphamide without bone marrow transplantation. Blood. 1996;87:491-494.http://bloodjournal.org/content/87/2/491.full.pdf+htmlhttp://www.ncbi.nlm.nih.gov/pubmed/8555470?tool=bestpractice.com[48]Brodsky RA, Chen AR, Dorr D, et al. High-dose cyclophosphamide for severe aplastic
anemia: long-term follow-up. Blood. 2010;115:2136-2141.http://www.ncbi.nlm.nih.gov/pubmed/20018919?tool=bestpractice.com然而,一项比较其和环孢素联合使用与参考标准的抗胸腺细胞球蛋白 (ATG) 加环孢素的前瞻性随机研究因为 HDC 组出现过量的死亡和系统性真菌感染而被提前终止。[49]Tisdale JF, Dunn DE, Geller N, et al. High-dose cyclophosphamide in severe aplastic anaemia: a randomised trial. Lancet. 2000;356:1554-1559.http://www.ncbi.nlm.nih.gov/pubmed/11075769?tool=bestpractice.com[50]Tisdale JF, Maciejewski JP, Nuñez O, et al. Late complications following treatment for severe aplastic anemia (SAA) with high-dose cyclophosphamide (Cy): follow-up of a randomized trial. Blood. 2002;100:4668-4670.http://bloodjournal.org/content/100/13/4668.fullhttp://www.ncbi.nlm.nih.gov/pubmed/12393567?tool=bestpractice.com对 ATG 难治性患者,HDC 在 70% 的患者中出现诱导反应,但未消除所有患者阵发性睡眠性血红蛋白尿克隆,并且随后有骨髓增生异常综合征 (MDS) 的报道。[51]Brodsky RA, Chen AR, Brodsky I, et al. High-dose cyclophosphamide as salvage therapy for severe aplastic anemia. Exp Hematol. 2004;32:435-440.http://www.ncbi.nlm.nih.gov/pubmed/15145211?tool=bestpractice.com鉴于如此严重的毒性和死亡率,不建议广泛使用无干细胞支持的 HDC 治疗新诊断的 AA 患者或 ATG 和环孢素失败的患者。尽管已经证明“中等剂量”的环磷酰胺可产生有意义的疗效,但它也能引起显著的毒性。[52]Scheinberg P, Townsley DM, Dimitriu B, et al. Even "moderate" dose cyclophosphamide for severe aplastic anemia is associated with significant toxicities and does not prevent relapse and clonal evolution. Blood (ASH Annual Meeting Abstracts). 2012;120:1259.http://www.bloodjournal.org/content/120/21/1259.full.pdf因此并不推荐将这一较低剂量用于治疗。
生长因子作为辅助治疗
在 ATG 和环孢素后使用粒细胞集落刺激因子 (G-CSF) 的理论基础是试图在达到血液学反应前(3 个月)降低感染风险,并改善三系反应,因为 G-CSF 可与其他造血生长因子联合作用刺激造血干细胞。[53]Bacigalupo A, Bruno B, Saracco P, et al; European Group for Blood and Marrow Transplantation (EBMT) Working Party on Severe Aplastic Anemia and the Gruppo Italiano Trapianti di Midolio Osseo (GITMO). Antilymphocyte globulin, cyclosporine, prednisolone, and granulocyte colony-stimulating factor for severe aplastic anemia: an update of the GITMO/EBMT study on 100 patients. Blood. 2000;95:1931-1934.http://bloodjournal.org/content/95/6/1931.fullhttp://www.ncbi.nlm.nih.gov/pubmed/10706857?tool=bestpractice.com随机研究比较了在 ATG 和环孢素后添加 G-CSF 与单独使用 ATG 和环孢素两种治疗方案,结果显示 4 年后在 MDS 或急性髓性白血病 (AML) 的发展上两种方法没有差异,尽管一项研究确实显示 G-CSF 治疗组复发率更低,另一项显示 G-CSF 治疗的前 3 个月可降低感染和住院天数。但是 G-CSF 并未改善疗效或总生存期。[54]Teramura M, Kimura A, Iwase S, et al. Treatment of severe aplastic anemia with antithymocyte globulin and cyclosporin A with or without G-CSF in adults; a multicenter randomized study in Japan. Blood. 2007;110:1756-1761.http://www.ncbi.nlm.nih.gov/pubmed/17526862?tool=bestpractice.com[55]Gluckman E, Rokicka-Milewska R, Hann I, et al; European Group for Blood and Marrow Transplantation Working Party for Severe Aplastic Anemia. Results and follow-up of a phase III randomized study of recombinant human-granulocyte stimulating factor as support for immunosuppressive therapy in patients with severe aplastic anaemia. Br J Haematol. 2002;119:1075-1082.http://www.ncbi.nlm.nih.gov/pubmed/12472591?tool=bestpractice.comEBMT 重型再生障碍性贫血的工作组报告了一项大型回顾性研究的结果,该项研究涉及 840 例采用 ATG 和环孢素治疗的患者,其中 43% 的患者接受了 G-CSF。在使用 G-CSF 的患者中,MDS 或 AML 的发病率为 10.9%,而未使用 G-CSF 的患者的发病率为 5.8%。[56]Socie G, Mary JY, Schrezenmeier H, et al. Granulocyte-stimulating factor and severe aplastic anemia: a survey by the European Group for Blood and Marrow Transplantation (EBMT). Blood. 2007;109:2794-2796.http://bloodjournal.org/content/109/7/2794.fullhttp://www.ncbi.nlm.nih.gov/pubmed/17110459?tool=bestpractice.com除前瞻性临床试验以外,不建议在 ATG 和环孢素后长期日常使用 G-CSF。
雄性激素
在 ATG 和环孢素开展前,雄激素羟甲烯龙广泛用于治疗 AA 已长达几十年。羟甲烯龙会在大约 25% 的患者中产生一种三系反应。它会刺激红细胞生成素生成,雄激素通过雌二醇转换刺激端粒酶生成。[42]Calado RT, Young NS. Telomere maintenance and human bone marrow failure. Blood. 2008;111:4446-4455.http://bloodjournal.org/content/111/9/4446.fullhttp://www.ncbi.nlm.nih.gov/pubmed/18239083?tool=bestpractice.com[43]Calado RT, Yewdell WT, Wilkerson KL, et al. Sex hormones, acting on the TERT gene, increase telomerase activity in human primary hematopoietic cells. Blood. 2009;114:2236-2243.http://www.ncbi.nlm.nih.gov/pubmed/19561322?tool=bestpractice.com对雄激素的反应增加了骨髓衰竭先天性病因的可能性。雄激素对大约 60% 的 Fanconi 贫血、或先天性角化不良患者有效。在与 ATG 联用时,比例更高。[40]Bacigalupo A, Chaple M, Hows J, et al. Treatment of aplastic anaemia (AA) with antilymphocyte globulin (ALG) and methylprednisolone (MPred) with or without androgens: a randomized trial from the EBMT SAA working party. Br J Haematol. 1993;83:145-151.http://www.ncbi.nlm.nih.gov/pubmed/8435323?tool=bestpractice.com[41]Leleu X, Terriou L, Duhamel A, et al. Long-term outcome in acquired aplastic anemia treated with an intensified dose schedule of horse antilymphocyte globulin in combination with androgens. Ann Hematol. 2006;85:711-716.http://www.ncbi.nlm.nih.gov/pubmed/16830141?tool=bestpractice.com羟甲烯龙具有肝毒性,可导致肝功能不全、临床黄疸、肝癌和肝紫癜。因此必须谨慎使用,定期监测肝功能并进行超声检查。由于会导致男性化,所以女性患者通常无法接受该治疗。
脐带血作为干细胞来源
脐带血也越来越多地被用作干细胞来源,因其可供无 HLA 匹配供体的患者进行移植。初步结果表明该方法在 AA 中可行,但需更多的经验确定其长期的治疗效果。[57]Mao P, Zhu Z, Wang H, et al. Sustained and stable hematopoietic donor-recipient mixed chimerism after unrelated cord blood transplantation for adult patients with severe aplastic anemia. Eur J Haematol. 2005;75:430-435.http://www.ncbi.nlm.nih.gov/pubmed/16191094?tool=bestpractice.com[58]Ohga S, Ichino K, Goto K, et al. Unrelated donor cord blood transplantation for childhood severe aplastic anemia after a modified conditioning. Pediatr Transplant. 2006;10:497-500.http://www.ncbi.nlm.nih.gov/pubmed/16712610?tool=bestpractice.com[59]Motwani J, Lawson SE, Darbyshire PJ. Successful HSCT using nonradiotherapy-based conditioning regimens and alternative donors in patients with Fanconi anaemia - experience in a single UK centre. Bone Marrow Transplant. 2005;36:405-410.http://www.ncbi.nlm.nih.gov/pubmed/15995715?tool=bestpractice.com[60]Vibhakar R, Radhi M, Rumelhart S, et al. Successful unrelated umbilical cord blood transplantation in children with Shwachman-Diamond syndrome. Bone Marrow Transplant. 2005;36:855-861.http://www.ncbi.nlm.nih.gov/pubmed/16113664?tool=bestpractice.com尽管脐带血移植对无合适成年供体的患者可行,但该手术非移植物植入的风险也很明显,大约为 40% 至 50%。
单倍体相合干细胞移植
已报道了 2 例阵发性睡眠性血红蛋白尿 (PNH) 患者使用单倍体相合供体及移植后环磷酰胺成功进行了干细胞移植。[61]Brodsky RA, Luznik L, Bolaños-Meade J, et al. Reduced intensity HLA-haploidentical BMT with post transplantation cyclophosphamide in nonmalignant hematologic diseases. Bone Marrow Transplant. 2008;42:523-527.http://www.nature.com/bmt/journal/v42/n8/full/bmt2008203a.htmlhttp://www.ncbi.nlm.nih.gov/pubmed/18622413?tool=bestpractice.com这种方法已得到进一步探索,并获得了有前景的初步结果,尤其是在缺乏供体特异性 HLA 抗体的患者中。[62]Clay J, Kulasekararaj AG, Potter V, et al. Nonmyeloablative peripheral blood haploidentical stem cell transplantation for refractory severe aplastic anemia. Biol Blood Marrow Transplant. 2014;20:1711-1716.http://www.bbmt.org/article/S1083-8791(14)00395-4/fulltexthttp://www.ncbi.nlm.nih.gov/pubmed/25016195?tool=bestpractice.com