Center for Gene Therapy, The Abigail Wexner Research Institute at Nationwide Children's Hospital, Columbus, Ohio.
Department of Pediatrics, The Ohio State University, Columbus.
JAMA Neurol. 2020 Sep 1;77(9):1122-1131. doi: 10.1001/jamaneurol.2020.1484.
Micro-dystrophin gene transfer shows promise for treating patients with Duchenne muscular dystrophy (DMD) using recombinant adeno-associated virus serotype rh74 (rAAVrh74) and codon-optimized human micro-dystrophin driven by a skeletal and cardiac muscle-specific promoter with enhanced cardiac expression (MHCK7).
To identify the 1-year safety and tolerability of intravenous rAAVrh74.MHCK7.micro-dystrophin in patients with DMD.
DESIGN, SETTING, AND PARTICIPANTS: This open-label, phase 1/2a nonrandomized controlled trial was conducted at the Nationwide Children's Hospital in Columbus, Ohio. It began on November 2, 2017, with a planned duration of follow-up of 3 years, ending in March 2021. The first 4 patients who met eligibility criteria were enrolled, consisting of ambulatory male children with DMD without preexisting AAVrh74 antibodies and a stable corticosteroid dose (≥12 weeks).
A single dose of 2.0 × 1014 vg/kg rAAVrh74.MHCK7.micro-dystrophin was infused through a peripheral limb vein. Daily prednisolone, 1 mg/kg, started 1 day before gene delivery (30-day taper after infusion).
Safety was the primary outcome. Secondary outcomes included micro-dystrophin expression by Western blot and immunohistochemistry. Functional outcomes measured by North Star Ambulatory Assessment (NSAA) and serum creatine kinase were exploratory outcomes.
Four patients were included (mean [SD] age at enrollment, 4.8 [1.0] years). All adverse events (n = 53) were considered mild (33 [62%]) or moderate (20 [38%]), and no serious adverse events occurred. Eighteen adverse events were considered treatment related, the most common of which was vomiting (9 of 18 events [50%]). Three patients had transiently elevated γ-glutamyltransferase, which resolved with corticosteroids. At 12 weeks, immunohistochemistry of gastrocnemius muscle biopsy specimens revealed robust transgene expression in all patients, with a mean of 81.2% of muscle fibers expressing micro-dystrophin with a mean intensity of 96% at the sarcolemma. Western blot showed a mean expression of 74.3% without fat or fibrosis adjustment and 95.8% with adjustment. All patients had confirmed vector transduction and showed functional improvement of NSAA scores and reduced creatine kinase levels (posttreatment vs baseline) that were maintained for 1 year.
This trial showed rAAVrh74.MHCK7.micro-dystrophin to be well tolerated and have minimal adverse events; the safe delivery of micro-dystrophin transgene; the robust expression and correct localization of micro-dystrophin protein; and improvements in creatine kinase levels and NSAA scores. These findings suggest that rAAVrh74.MHCK7.micro-dystrophin can provide functional improvement that is greater than that observed under standard of care.
ClinicalTrials.gov Identifier: NCT03375164.
使用重组腺相关病毒血清型 rh74（rAAVrh74）和受骨骼肌和心肌特异性启动子驱动的编码优化的人类微小肌营养不良蛋白，对患有杜氏肌营养不良症（DMD）的患者进行微肌营养不良基因转移显示出治疗前景，该启动子具有增强的心脏表达（MHCK7）。
确定静脉内 rAAVrh74.MHCK7.微肌营养不良蛋白在 DMD 患者中的 1 年安全性和耐受性。
设计、设置和参与者：这项开放标签、1/2a 期非随机对照试验在俄亥俄州哥伦布市的全国儿童医院进行。它于 2017 年 11 月 2 日开始，计划随访 3 年，于 2021 年 3 月结束。前 4 名符合入选标准的患者被纳入研究，包括没有预先存在的 AAVrh74 抗体且稳定接受皮质类固醇治疗（≥12 周）的活动性男性 DMD 儿童。
每位患者接受 2.0×1014 vg/kg 的 rAAVrh74.MHCK7.微肌营养不良蛋白静脉输注。基因传递前 1 天开始每日口服 1 毫克/千克泼尼松龙（输注后 30 天逐渐减量）。
安全性是主要终点。次要终点包括 Western blot 和免疫组织化学检测微肌营养不良蛋白的表达。北星活动评估（NSAA）和血清肌酸激酶测量的功能结果为探索性终点。
共纳入 4 名患者（入组时的平均[SD]年龄，4.8[1.0]岁）。所有不良事件（n=53）均被认为是轻度（33[62%]）或中度（20[38%]），没有严重不良事件发生。18 项不良事件被认为与治疗有关，其中最常见的是呕吐（18 项事件中的 9 项[50%]）。3 名患者的γ-谷氨酰转移酶一过性升高，用皮质类固醇治疗后恢复正常。12 周时，腓肠肌活检标本的免疫组织化学显示所有患者均有强烈的转基因表达，平均 81.2%的肌纤维表达微肌营养不良蛋白，细胞膜的平均强度为 96%。Western blot 显示未经脂肪或纤维化校正的平均表达率为 74.3%，校正后的表达率为 95.8%。所有患者均证实有载体转导，并显示 NSAA 评分的功能改善和肌酸激酶水平降低（治疗后与基线相比），这种改善持续了 1 年。
这项试验表明，rAAVrh74.MHCK7.微肌营养不良蛋白具有良好的耐受性和最小的不良事件；微肌营养不良蛋白转基因的安全传递；微肌营养不良蛋白蛋白的强大表达和正确定位；以及肌酸激酶水平和 NSAA 评分的改善。这些发现表明，rAAVrh74.MHCK7.微肌营养不良蛋白可以提供比标准治疗更大的功能改善。
ClinicalTrials.gov 标识符：NCT03375164。
Zotero 插件
