GenSight Biologics, Paris, France.
Centre Hospitalier National d'Ophtalmologie des Quinze-Vingts, Paris, France.
JAMA Ophthalmol. 2019 Apr 1;137(4):399-406. doi: 10.1001/jamaophthalmol.2018.6902.
Intravitreal gene therapy is regarded as generally safe with limited mild adverse events, but its systemic effects remain to be investigated.
To examine the association between immune response and intraocular inflammation after ocular gene therapy with recombinant adeno-associated virus 2 carrying the ND4 gene (rAAV2/2-ND4).
DESIGN, SETTING, AND PARTICIPANTS: This secondary analysis of an open-label, dose-escalation phase 1/2 randomized clinical trial of rAAV2/2-ND4 included data from February 13, 2014 (first patient visit), to March 30, 2017 (last patient visit at week 96), the first 2 years after injection. Patients older than 15 years with diagnosed ND4 Leber hereditary optic neuropathy (LHON) and visual acuity of at least counting fingers were enrolled in 1 of 5 cohorts. Four dose cohorts of 3 patients each were treated sequentially. An extension cohort of 3 patients received the dose of 9 × 1010 viral genomes per eye.
Patients received increasing doses of rAAV2/2-ND4 (9 × 109, 3 × 1010, 9 × 1010, and 1.8 × 1011 viral genomes per eye) as a single unilateral intravitreal injection. Patients were monitored for 96 weeks after injection; ocular examinations were performed regularly, and blood samples were collected for immunologic testing.
A composite ocular inflammation score (OIS) was calculated based on grades of anterior chamber cells and flare, vitreous cells, and haze according to the Standardization of Uveitis Nomenclature. The systemic immune response was quantified by enzyme-linked immunospot (cellular immune response), enzyme-linked immunosorbent assay (IgG titers), and luciferase assay (neutralizing antibody [NAb] titers).
The present analysis included 15 patients (mean [SD] age, 47.9 [17.2] years; 13 men and 2 women) enrolled in the 5 cohorts of the clinical trial. Thirteen patients experienced intraocular inflammation after rAAV2/2-ND4 administration. Mild anterior chamber inflammation and vitritis were reported at all doses, and all cases were responsive to treatment. A maximum OIS of 9.5 was observed in a patient with history of idiopathic uveitis. Overall, OIS was not associated with the viral dose administered. No NAbs against AAV2 were detected in aqueous humor before treatment. Two patients tested positive for cellular immune response against AAV2 at baseline and after treatment. Humoral immune response was not apparently associated with the dose administered or with the immune status of patients at baseline. No association was found between OISs and serum NAb titers.
In this study, intravitreal administration of rAAV2/2-ND4 in patients with LHON was safe and well tolerated. Further investigations may shed light into the local immune response to rAAV2/2-ND4 as a potential explanation for the observed intraocular inflammation.
眼内基因治疗被认为具有一般安全性，仅有轻微的不良反应，但仍需研究其全身作用。
研究携带 ND4 基因的重组腺相关病毒 2（rAAV2/2-ND4）眼内基因治疗后免疫反应与眼内炎症之间的关系。
设计、设置和参与者：这是一项对 rAAV2/2-ND4 的开放标签、剂量递增 1/2 期随机临床试验的二次分析，纳入了 2014 年 2 月 13 日（第一次就诊）至 2017 年 3 月 30 日（第 96 周最后一次就诊）的数据，即注射后前 2 年。招募了 15 名年龄大于 15 岁、诊断为 ND4 莱伯遗传性视神经病变（LHON）且视力至少为指数的患者，入组 5 个队列中的 1 个。4 个剂量队列各有 3 名患者，依次接受治疗。3 名患者接受了每只眼 9×1010 个病毒基因组的扩展队列。
患者接受递增剂量的 rAAV2/2-ND4（每只眼 9×109、3×1010、9×1010 和 1.8×1011 个病毒基因组）单次单侧玻璃体内注射。注射后 96 周内对患者进行监测；定期进行眼部检查，并采集血样进行免疫检测。
根据前房细胞和闪光、玻璃体细胞和混浊的分级，基于标准葡萄膜炎命名法，计算了复合眼内炎症评分（OIS）。通过酶联免疫斑点（细胞免疫反应）、酶联免疫吸附试验（IgG 滴度）和荧光素酶测定（中和抗体 [NAb] 滴度）定量检测全身免疫反应。
本分析纳入了临床试验的 5 个队列中的 15 名患者（平均[标准差]年龄 47.9[17.2]岁；13 名男性和 2 名女性）。13 名患者在 rAAV2/2-ND4 给药后出现眼内炎症。所有剂量均出现轻度前房炎症和玻璃体炎症，所有病例均对治疗有反应。一名有特发性葡萄膜炎病史的患者出现 9.5 分的最高 OIS。总体而言，OIS 与给予的病毒剂量无关。治疗前在房水中未检测到针对 AAV2 的 NAb。2 名患者在基线和治疗后针对 AAV2 的细胞免疫反应呈阳性。体液免疫反应与给予的剂量或患者的基线免疫状态无明显关联。未发现 OIS 与血清 NAb 滴度之间存在关联。
在这项研究中，LHON 患者玻璃体内给予 rAAV2/2-ND4 是安全且耐受良好的。进一步的研究可能有助于阐明针对 rAAV2/2-ND4 的局部免疫反应，这可能是观察到的眼内炎症的潜在解释。
