Obinutuzumab in treating refractory primary membranous nephropathy: a single-center study
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摘要:
目的 评估奥妥珠单抗(OBZ)治疗难治性原发性膜性肾病(pMN)的有效性及安全性。 方法 回顾性分析2022年1月至2024年9月在海军军医大学第一附属医院肾内科接受OBZ治疗的15例难治性pMN患者的临床资料,包括患者基本信息、相关实验室指标、临床及免疫学结局、不良事件的发生情况等。 结果 15例难治性pMN患者中,14例(93.3%)为磷脂酶A2受体(PLA2R)相关膜性肾病(10例肾组织PLA2R阳性,4例肾组织PLA2R检测结果未记录但血清PLA2R抗体阳性)。15例患者在随访期间均达到临床缓解,其中4例(26.7%)达到完全缓解,11例(73.3%)达到部分缓解。在12例血清PLA2R抗体阳性患者中,11例OBZ治疗前血清PLA2R抗体持续阳性,其中9例(81.8%)在OBZ治疗后转阴。15例患者既往均接受过免疫抑制治疗,均属于难治性pMN,其中7例(46.7%)接受过环磷酰胺联合糖皮质激素治疗,2例(13.3%)接受过钙调磷酸酶抑制剂联合糖皮质激素治疗,11例(73.3%)接受过利妥昔单抗治疗。治疗过程中共观察到2例(13.3%)不良事件,1例患者出现一过性肝功能不全,停用阿托伐他汀后,转氨酶恢复正常;1例患者在2次OBZ用药间隔期结核感染T细胞斑点试验转阳,经异烟肼联合利福平治疗后,顺利完成后续OBZ治疗并达到临床缓解。 结论 OBZ治疗难治性pMN具有良好的临床疗效,且不良事件发生率较低。 Abstract:Objective To evaluate the efficacy and safety of obinutuzumab (OBZ) in the treatment of refractory primary membranous nephropathy (pMN). Methods The clinical data of 15 patients with refractory pMN who received OBZ treatment in Department of Nephrology of The First Affiliated Hospital of Naval Medical University between Jan. 2022 and Sep. 2024 were retrospectively analyzed, and they included basic information, relevant laboratory indexes, clinical and immunological outcomes, and adverse events. Results Among the 15 patients with refractory pMN, 14 (93.3%) were phospholipase A2 receptor (PLA2R)-associated membranous nephropathy (10 cases with positive PLA2R by renal biopsy and 4 cases with no recorded PLA2R results by renal biopsy but with positive serum PLA2R antibodies). During the follow-up period, all 15 patients achieved clinical remission, with 4 (26.7%) patients achieving complete remission and 11 (73.3%) patients achieving partial remission. Of the 12 patients with positive serum PLA2R antibodies, 11 patients had continuously positive serum PLA2R antibodies before OBZ treatment, and 9 (81.8%) patients achieved immunological remission after OBZ treatment. All the 15 patients had previously received immunosuppressive therapy, and all of them were classified as refractory pMN, with 7 (46.7%) patients having been treated with cyclophosphamide combined with corticosteroids, 2 (13.3%) patients having been treated with calcineurin inhibitor combined with corticosteroids, 11 (73.3%) patients having received rituximab. During the treatment, 2 (13.3%) cases of adverse events were observed: 1 patient experienced transient liver dysfunction, and the transaminase returned to normal after discontinuing atorvastatin; another patient developed a positive T-cell spot test for Tuberculosis infection during the intertreatment interval and successfully completed the subsequent OBZ treatment and achieved clinical remission after treatment with isoniazid and rifampicin. Conclusion OBZ demonstrates favorable clinical efficacy in the treatment of refractory pMN, with a low incidence of adverse events. -
Keywords:
- obinutuzumab /
- phospholipase A2 receptor /
- membranous nephropathy /
- rituximab /
- cyclophosphamide
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膜性肾病(membranous nephropathy,MN)是成人肾病综合征(nephrotic syndrome,NS)最常见的病理类型之一[1]。虽然部分患者可能会自发缓解,但仍有50%以上的患者15年内进展至终末期肾病。原发性膜性肾病(primary membranous nephropathy,pMN)约占所有MN的75%[2]。pMN是以肾小球毛细血管襻上皮侧大量免疫复合物沉积为特点的免疫复合物相关肾小球疾病,这些免疫复合物主要由内源性足细胞表面抗原和循环抗体组成,沉积于足细胞和肾小球基底膜之间[3]。2009年首次报道了pMN的自身抗原——磷脂酶A2受体(phospholipase A2 receptor,PLA2R),大约70%的MN为PLA2R相关MN,且PLA2R抗体水平与pMN的病情严重程度、自发缓解率和临床预后等密切相关[4]。根据改善全球肾脏病预后组织(Kidney Disease:Improving Global Outcomes,KDIGO)指南推荐,对于PLA2R抗体阳性的NS患者,在排除继发性MN可能后,可不经肾活检诊断为pMN[5]。目前,PLA2R抗体诊断pMN的特异度可达99%,已成为临床上一种高效、可靠且无创的pMN诊断方法。
MN的自身免疫性质提示了免疫抑制治疗的有效性。B细胞在免疫反应中分泌自身抗体是引起组织损伤的关键因素,对B细胞在MN发病机制中作用的认识推动了针对B细胞治疗MN策略的发展[6]。利妥昔单抗(rituximab,RTX)是一种针对B细胞表面CD20分子的鼠/人IgG1κ嵌合单克隆抗体,已有研究证实RTX在60%~80%的pMN病例治疗中有效,但仍有20%~40%的pMN患者需要寻求其他治疗方法[7-8]。
奥妥珠单抗(obinutuzumab,OBZ)是一种人源化的Ⅱ型CD20抗体,通过直接导致细胞死亡和抗体介导的细胞毒性2种方式诱导B细胞凋亡[9-10]。本研究旨在探讨OBZ治疗MN尤其是难治性PLA2R相关pMN的有效性及安全性。
1 资料和方法
1.1 研究对象
回顾性纳入2022年1月至2024年9月在海军军医大学第一附属医院肾内科接受OBZ治疗的难治性pMN患者共15例。15例患者中,14例接受过肾活检,其中10例有肾组织PLA2R检测结果记录,均为阳性(100%)。9例有免疫荧光检测结果,其中IgG阳性9例(IgG均+++),IgG1阴性9例,IgG4阳性9例(+,1例;++,4例;+++,3例;++++,1例)。
研究对象纳入标准:(1)OBZ治疗时年龄≥18岁(含临界值),性别不限;(2)经肾脏活检病理诊断为pMN,或未经活检的NS患者在排除继发性疾病可能且血清PLA2R抗体阳性诊断为pMN;(3)难治性MN,即经过足够剂量与持续时间的一线免疫抑制治疗后PLA2R抗体持续高水平或无变化,或随访时间超过6个月血清白蛋白水平低、仍表现为持续性NS[5]。排除标准:(1)继发性MN或合并经病理活检确诊的其他肾脏疾病;(2)存在或怀疑无法控制的或需要治疗的感染;(3)合并1型或2型糖尿病;(4)处于终末期肾功能衰竭;(5)首次诊断为MN且未接受过其他治疗的初治患者;(6)研究者认为不适合纳入本研究的患者。
1.2 治疗方法
OBZ一次用药剂量为1 g,分为100 mg、400 mg、500 mg于3个阶段静脉滴注,以降低发生首剂效应的可能性。输注OBZ前,静脉注射甲泼尼龙琥珀酸钠80 mg,联合肌内注射异丙嗪25 mg,以预防不良反应的发生。给药次数由临床医师依据KDIGO指南推荐[5]并结合患者病情特点决定。首次与第2次给药间隔通常为14 d,第3次用药时间根据患者B细胞水平进行个体化调整。
1.3 评估指标
从电子病历系统中收集患者的基本资料(性别、年龄、病程、BMI、既往接受过的治疗方案)、OBZ用药剂量、相关实验室指标(24 h尿蛋白定量、尿蛋白/肌酐比值、血清白蛋白、血肌酐、CD19+ B细胞计数、血清PLA2R抗体滴度、尿α1-微球蛋白、尿β2-微球蛋白等)、不良事件发生情况等。
1.4 预后评定
随访时间点为初次给药后1、3、6、12个月及之后的最后一次复查。主要结局指标为患者临床与免疫学缓解率。依据KDIGO指南[5],临床缓解包括部分缓解与完全缓解。部分缓解定义为0.3 g/d≤24 h尿蛋白定量<3.5 g/d,或0.3 g/g≤尿蛋白/肌酐比值<3.5 g/g,且相较于基线水平下降幅度>50%;完全缓解定义为24 h尿蛋白定量<0.3 g/d或尿蛋白/肌酐比值<0.3 g/g;未达到上述标准视为未缓解。
免疫学结果仅在PLA2R相关MN(血清PLA2R抗体阳性)病例中进行评估。免疫学缓解定义为血清PLA2R抗体转阴(ELISA:PLA2R抗体滴度<14 RU/mL[11];间接免疫荧光法:PLA2R抗体滴度<2 RU/mL)。
次要结局指标包括24 h尿蛋白定量、血清PLA2R抗体滴度、血清白蛋白、血肌酐、CD19+ B细胞计数、尿α1-微球蛋白、尿β2-微球蛋白的变化趋势,以及不良事件的发生情况等。
1.5 统计学处理
使用SPSS 25软件和GraphPad Prism 8.0.0软件进行数据分析。计数资料以例数和百分数表示,符合正态分布的计量资料以x±s表示,非正态分布的计量资料以M(Q1,Q3)表示。临床与免疫学缓解率通过Kaplan-Meier生存曲线描述,配对样本的组间比较使用Wilcoxon符号秩检验。检验水准(α)为0.05,所有检验均为双尾检验。
2 结果
2.1 基线资料分析
15例患者中,男10例,女5例,男女比为2∶1;14例(93.3%)经肾活检确诊为pMN;1例未行肾活检,但排除继发因素可能且血清PLA2R抗体阳性,确诊为pMN。14例肾活检患者中,MN Ⅰ期1例(7.1%),Ⅰ/Ⅱ期1例(7.1%),Ⅱ期8例(57.1%),Ⅱ/Ⅲ期2例(14.3%),未记录分期2例(14.3%)。患者发病年龄为52(37,62)岁,接受OBZ治疗时年龄为58(50,66)岁、病程为51(29,168)个月。15例患者既往均接受过免疫抑制治疗,属于难治性MN。其中7例(46.7%)接受过环磷酰胺联合糖皮质激素治疗,2例(13.3%)接受过钙调磷酸酶抑制剂联合糖皮质激素治疗,11例(73.3%)接受过RTX治疗。14例(93.3%)为PLA2R相关MN,其中10例肾组织PLA2R阳性(+,1例;++,6例;+++,3例);4例无肾组织PLA2R检测结果记录,但血清PLA2R抗体阳性。
7例(46.7%)患者接受总剂量1 g的OBZ治疗。6例(40.0%)患者接受总剂量2 g的OBZ治疗,其中5例2次治疗间隔为14 d,1例间隔为4个月。另有2例(13.3%)患者均在第1次OBZ治疗后14 d接受第2次治疗,分别在第5个月、第14个月接受第3次OBZ治疗,OBZ总剂量均为3 g。
15例患者在接受OBZ治疗前,BMI为23(21,25)kg/m2,24 h尿蛋白定量为5.6(2.9,9.2)g/d,血清白蛋白为24.0(20.0,32.0)g/L,血肌酐为82.0(70.0,100.0)μmol/L,CD19+ B细胞计数为29.6(11.9,176.9)/µL,尿α1-微球蛋白为11.5(8.2,34.1)mg/L,尿β2-微球蛋白为0.4(0.2,0.9)mg/L;整个病程中血清PLA2R抗体滴度峰值为112.5(66.4,242.7)RU/mL。
2.2 治疗有效性分析
2.2.1 主要结局指标
在随访期间内,15例(100%)患者均达到临床缓解标准,其中4例(26.7%)患者达到完全缓解,11例(73.3%)达到部分缓解。在既往接受过RTX治疗的11例患者中,2例(18.2%)患者达到完全缓解,9例(81.1%)患者达到部分缓解。12例血清PLA2R抗体阳性患者中,1例因既往治疗血清PLA2R抗体转阴,余11例在接受OBZ治疗前血清PLA2R抗体检测阳性,其中2例患者未定期监测血清PLA2R抗体滴度,另9例(81.8%)患者在随访期间达到免疫学缓解标准。见图 1、表 1。
图 1 难治性pMN患者经奥妥珠单抗治疗后的临床与免疫学结局Fig. 1 Clinical and immunological outcomes of refractory pMN patients after obinutuzumab treatmentProbability of achieving clinical remission (partial or complete remission) in total cohort (n=15) and immunological remission in phospholipase A2 receptor-associated subgroups (n=11) following obinutuzumab therapy. pMN: Primary membranous nephropathy.表 1 15例难治性pMN患者奥妥珠单抗治疗前后的结局指标变化Table 1 Changes of outcome indexes of 15 refractory pMN patients before and after obinutuzumab treatmentCase No. PLA2R-associateda 24h-UP/(g·d-1) Salb/(g·L-1) Serum anti-PLA2R titer/(RU·mL-1) Clinical remission Immunological remission Initialb Finalc Initialb Finalc Initiald Finalc 1 Yes 10.76 2.44 20.0 24.0 36.4 <5 Yes Yes 2 Yes 2.18 0.11 32.0 46.0 Negative Negative Yes Negative 3 Yes 3.24 0.32 27.0 45.0 141.4 <2 Yes Yes 4 Yes 8.86 0.70 20.0 43.0 158.1 <2 Yes Yes 5 Yes 10.75 Unknowne 24.0 33.0 67.6 <2 Yesf Yes 6 Yes 0.76 0.24 39.0 44.0 76.8 Negativeg Yes Negativeg 7 Yes 9.17 3.46 21.0 42.0 246.7 <5 Yes Yes 8 Yes 4.01 0.45 25.0 42.5 513.5 0.68 Yes Yes 9 Yes 6.60 2.65 19.0 28.0 230.7 Unknowne Yes Unknowne 10 Yes 5.55 0.12 27.0 44.0 66.0 Unknowne Yes Unknowne 11 Yes 1.56 0.50 38.0 42.0 Negative Negative Yes Negative 12 Yes 7.72 1.18 21.0 39.0 83.6 <2 Yes Yes 13 Yes 12.34 1.46 20.0 38.0 330.2 <2 Yes Yes 14 Yes 4.77 2.50 20.0 31.3 21.2 <2 Yes Yes 15 No 2.85 0.27 36.0 47.0 Negative Negative Yes Negative M (Q1, Q3) 5.6 (2.9, 9.2) 0.6 (0.3, 2.5) 24.0 (20.0, 32.0) 42.0 (33.0, 44.0) 112.5 (66.4, 242.7) 2.0 (2.0, 3.5) P value 0.001 0.001 0.008 a: Positive PLA2R by renal biopsy, or negative PLA2R by renal biopsy but positive serum PLA2R antibody; b: The level of laboratory indicators before treatment with obinutuzumab; c: The level of laboratory indicators at the last follow-up; d: The peak value of serum PLA2R antibody titers during the course of pMN; e: 24h-UP or serum PLA2R antibody titers were not detected during follow-up; f: The urine protein-to-creatinine ratio was 0.9 g/g, compared with 6.4 g/g before obinutuzumab treatment, meeting the criteria for clinical remission; g: Serum PLA2R antibody turned negative before obinutuzumab treatment. pMN: Primary membranous nephropathy; PLA2R: Phospholipase A2 receptor; 24h-UP: 24 h urinary protein; Salb: Serum albumin. 2.2.2 次要结局指标
与OBZ治疗前相比,最后一次随访时24 h尿蛋白定量由5.6(2.9,9.2)g/d下降至0.6(0.3,2.5)g/d(P=0.001),血清PLA2R抗体滴度由112.5(66.4,242.7)RU/mL下降至2.0(2.0,3.5)RU/mL(P=0.008,间接免疫荧光法阴性结果取2.0 RU/mL),血清白蛋白由24.0(20.0,32.0)g/L增加至42.0(33.0,44.0)g/L(P=0.001),尿α1-微球蛋白、β2-微球蛋白分别由11.5(8.2,34.1)mg/L、0.4(0.2,0.9)mg/L下降至9.5(2.4,24.4)mg/L、0.2(0.1,0.4)mg/L(P=0.047、0.028),血肌酐、CD19+ B细胞计数与治疗前相比差异均无统计学意义[83.0(70.5,91.0)μmol/L vs 82.0(70.0,100.0)μmol/L,P=0.131;9.0(1.0,61.9)/µL vs 29.6(11.9,176.9)/µL,P=0.196)]。见表 1。
以接受OBZ治疗前的结果作为基线水平,24 h尿蛋白定量、血清白蛋白、血清PLA2R抗体滴度变化趋势如图 2。24 h尿蛋白定量在初次给药后1、3、6、12个月时分别下降至2.7(1.3,6.8)、1.9(0.5,2.9)、1.6(0.3,4.1)、0.5(0.1,1.2)g/d,与基线水平相比差异均有统计学意义(P=0.039、0.002、0.001、0.018)。
图 2 难治性pMN患者奥妥珠单抗治疗后12个月内的实验室指标变化趋势Fig. 2 Trends in laboratory indexes of refractory pMN patients within 12 months after obinutuzumab treatmentAfter obinutuzumab treatment, the 24h-UP was significantly decreased in 14 patients, the Salb level was significantly increased in 15 patients, and the serum PLA2R antibody titer was significantly decreased in 9 patients with serologically antibody-positive and antibody titers monitored during follow-up. The data were presented as M (IQR). pMN: Primary membranous nephropathy; 24h-UP: 24 h urinary protein; Salb: Serum albumin; PLA2R: Phospholipase A2 receptor.血清白蛋白在初次给药后1、3、6、12个月时分别上升至28.0(24.0,39.0)、34.0(29.0,39.0)、38.2(33.0,41.8)、44.0(42.3,45.5)g/L,与基线水平相比差异均有统计学意义(P=0.001、0.003、0.002、0.008)。
血肌酐在初次给药后1、3、6、12个月时分别为83.0(72.8,95.5)、84.0(65.0,95.0)、82.0(63.5,94.0)、85.5(69.0,94.5)μmol/L,与基线水平相比差异均无统计学意义(均P>0.05),提示在治疗期间患者肾功能稳定。
CD19+ B细胞计数在初次给药后1、3、6个月时分别下降至1.0(1.0,1.0)、1.0(0.9,1.0)、1.0(1.0,1.1)/µL,与基线水平相比差异均有统计学意义(P=0.003、0.008、0.005)。在给药后12个月,CD19+ B细胞计数回升至50.8(18.5,85.2)/µL,与基线水平相比差异无统计学意义(P=0.674)。
初次给药后6、12个月时尿α1-微球蛋白分别为5.5(2.1,21.0)mg/L、3.8(2.2,18.2)mg/L,尿β2-微球蛋白分别为0.2(0.1,0.2)mg/L、0.3(0.2,0.4)mg/L,与基线水平相比均未见显著回升(均P>0.05)。
2.3 不良事件发生情况
在整个治疗及随访过程中,未观察到严重不良事件,仅有2例(13.3%)患者发生了不良事件。1例患者在用药3个月后发现转氨酶水平轻度升高,停用阿托伐他汀,后续随访时转氨酶水平恢复至正常参考值范围。另1例患者在首次接受OBZ治疗后,结核感染T细胞斑点试验(T-cell spot test for Tuberculosis infection,T-SPOT)转阳,接受异烟肼联合利福平治疗后无明显结核活动迹象,成功完成后续OBZ治疗并达到了临床与免疫学缓解。
3 讨论
本研究重点探讨了OBZ治疗难治性pMN,尤其是针对PLA2R相关难治性pMN的有效性及安全性。研究共纳入了在海军军医大学第一附属医院肾内科治疗的15例pMN患者,既往均接受过免疫抑制治疗(11例接受过RTX治疗),属于难治性MN,其中14例为PLA2R相关MN。在随访期间内,15例患者均达到临床缓解,其中4例(26.7%)实现完全缓解。在12例血清PLA2R抗体阳性的患者中,因既往免疫治疗,11例患者在OBZ治疗前血清PLA2R抗体持续阳性,9例(81.8%)患者在OBZ治疗后转阴,达到免疫学缓解。此前,Lin等[12]的研究中18例难治性MN的临床缓解率达到94.4%;Su等[13]研究显示,OBZ治疗的39例难治性MN临床缓解率为82.1%,免疫学缓解率为87.1%。这些研究均证实了OBZ治疗难治性MN的有效性。
在PLA2R相关MN中,PLA2R抗体滴度是评估疾病活动性的关键生物标志物,高滴度抗体与不良临床预后密切相关[14]。降低PLA2R抗体水平是MN治疗的关键目标之一,抗体滴度的下降预示着临床上蛋白尿的改善,治疗结束时PLA2R抗体水平可以作为预后评估的重要依据[12]。
在本研究中,未观察到严重不良事件的发生。1例患者在用药3个月后出现轻度转氨酶升高,停用阿托伐他汀后转氨酶恢复正常。另1例患者在首次接受OBZ治疗后T-SPOT转阳,予异烟肼联合利福平治疗后顺利完成后续OBZ治疗并达到了临床与免疫学缓解。由此可见,OBZ治疗难治性MN未明显增加不良事件的发生率。
目前,RTX在MN的治疗中得到广泛应用,KDIGO指南也推荐使用RTX治疗MN[5]。但随着RTX的广泛使用,出现RTX耐药的患者逐渐增多,约23%接受RTX治疗的MN患者中检测到RTX抗体[15]。这些患者随着RTX抗体的产生血清RTX水平持续下降,部分产生RTX抗体的患者对再次RTX治疗无反应[16],针对这部分患者需要探索新的治疗方案。
与RTX相比,OBZ与CD20抗原的结合机制不同,且经过糖工程改造,OBZ与效应细胞上的Ig Fcγ受体Ⅲ亲和力更高,不仅显著增强了抗体依赖的细胞介导的细胞毒性作用,还减少了补体依赖的细胞毒性作用。OBZ还可通过溶酶体途径直接诱导B细胞死亡[17-19]。本研究中,11例既往接受过RTX治疗的患者在OBZ治疗后均达到临床缓解,随访3个月时10例(90.9%)患者实现了B细胞耗竭。Lin等[12]的研究中,12例既往接受过RTX治疗但效果欠佳的MN患者在OBZ治疗后均达到临床缓解,并且OBZ治疗的MN患者中位缓解时间为2.7个月,这一数据显著低于Ruggenenti等[20]研究中RTX治疗MN患者的中位缓解时间(7.1个月)。因此,相较于Ⅰ型CD20抗体,OBZ能更迅速、有效地诱导外周B细胞耗竭,且较少出现严重不良事件和感染。
本研究存在以下不足之处:(1)样本量较小;(2)数据有限或存在部分缺失;(3)随访周期较短。为了克服这些不足对研究结果的影响,本研究制定了严格的纳入标准,并进行了详尽的随访,确保数据的完整性,但研究结果仍可能存在偏倚。因此,需要更多的临床研究来进一步验证OBZ治疗MN的有效性与安全性。
综上所述,本研究分析了15例从OBZ治疗中获益的难治性pMN患者的临床资料,这些患者均有超过1年的MN病史,在接受OBZ治疗后所有患者均实现了临床缓解。尽管本研究结果尚需大规模随机对照试验进一步验证,但OBZ的药理和生理作用机制,加之目前的临床疗效,均支持OBZ治疗MN的有效性,并且未发现明显的严重不良反应。因此,对于标准免疫抑制疗法或RTX治疗效果不佳的MN患者,特别是PLA2R相关MN患者,OBZ治疗可作为一个值得考虑的方案。
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图 1 难治性pMN患者经奥妥珠单抗治疗后的临床与免疫学结局
Fig. 1 Clinical and immunological outcomes of refractory pMN patients after obinutuzumab treatment
Probability of achieving clinical remission (partial or complete remission) in total cohort (n=15) and immunological remission in phospholipase A2 receptor-associated subgroups (n=11) following obinutuzumab therapy. pMN: Primary membranous nephropathy.
图 2 难治性pMN患者奥妥珠单抗治疗后12个月内的实验室指标变化趋势
Fig. 2 Trends in laboratory indexes of refractory pMN patients within 12 months after obinutuzumab treatment
After obinutuzumab treatment, the 24h-UP was significantly decreased in 14 patients, the Salb level was significantly increased in 15 patients, and the serum PLA2R antibody titer was significantly decreased in 9 patients with serologically antibody-positive and antibody titers monitored during follow-up. The data were presented as M (IQR). pMN: Primary membranous nephropathy; 24h-UP: 24 h urinary protein; Salb: Serum albumin; PLA2R: Phospholipase A2 receptor.
表 1 15例难治性pMN患者奥妥珠单抗治疗前后的结局指标变化
Table 1 Changes of outcome indexes of 15 refractory pMN patients before and after obinutuzumab treatment
Case No. PLA2R-associateda 24h-UP/(g·d-1) Salb/(g·L-1) Serum anti-PLA2R titer/(RU·mL-1) Clinical remission Immunological remission Initialb Finalc Initialb Finalc Initiald Finalc 1 Yes 10.76 2.44 20.0 24.0 36.4 <5 Yes Yes 2 Yes 2.18 0.11 32.0 46.0 Negative Negative Yes Negative 3 Yes 3.24 0.32 27.0 45.0 141.4 <2 Yes Yes 4 Yes 8.86 0.70 20.0 43.0 158.1 <2 Yes Yes 5 Yes 10.75 Unknowne 24.0 33.0 67.6 <2 Yesf Yes 6 Yes 0.76 0.24 39.0 44.0 76.8 Negativeg Yes Negativeg 7 Yes 9.17 3.46 21.0 42.0 246.7 <5 Yes Yes 8 Yes 4.01 0.45 25.0 42.5 513.5 0.68 Yes Yes 9 Yes 6.60 2.65 19.0 28.0 230.7 Unknowne Yes Unknowne 10 Yes 5.55 0.12 27.0 44.0 66.0 Unknowne Yes Unknowne 11 Yes 1.56 0.50 38.0 42.0 Negative Negative Yes Negative 12 Yes 7.72 1.18 21.0 39.0 83.6 <2 Yes Yes 13 Yes 12.34 1.46 20.0 38.0 330.2 <2 Yes Yes 14 Yes 4.77 2.50 20.0 31.3 21.2 <2 Yes Yes 15 No 2.85 0.27 36.0 47.0 Negative Negative Yes Negative M (Q1, Q3) 5.6 (2.9, 9.2) 0.6 (0.3, 2.5) 24.0 (20.0, 32.0) 42.0 (33.0, 44.0) 112.5 (66.4, 242.7) 2.0 (2.0, 3.5) P value 0.001 0.001 0.008 a: Positive PLA2R by renal biopsy, or negative PLA2R by renal biopsy but positive serum PLA2R antibody; b: The level of laboratory indicators before treatment with obinutuzumab; c: The level of laboratory indicators at the last follow-up; d: The peak value of serum PLA2R antibody titers during the course of pMN; e: 24h-UP or serum PLA2R antibody titers were not detected during follow-up; f: The urine protein-to-creatinine ratio was 0.9 g/g, compared with 6.4 g/g before obinutuzumab treatment, meeting the criteria for clinical remission; g: Serum PLA2R antibody turned negative before obinutuzumab treatment. pMN: Primary membranous nephropathy; PLA2R: Phospholipase A2 receptor; 24h-UP: 24 h urinary protein; Salb: Serum albumin. -
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