听力障碍是人类最常见的感觉障碍性疾病,常伴有社会孤立、言语功能衰退、抑郁或认知缺陷,给个人、家庭和社会造成巨大负担。据世界卫生组织(WHO)统计,全球患有中度以上(致残性)听力障碍的人数约4.66亿,约占世界总人口的5%。据2016年中国聋儿康复研究中心数据分析,我国听力障碍现患率为15.8%,约合2亿人,致残性听力障碍患者约7000万人,严重危害我国人民健康。全球约2600万先天性耳聋患者,我国每年约3万新生聋儿,其中60%与遗传因素有关。现已鉴定出超过150个致聋基因,6000多个变异位点,临床上尚无任何治疗药物。

近日,复旦大学附属眼耳鼻喉科医院领衔在The Lancet上以长文的形式发表题为AAV1-hOTOF Gene Therapy for Autosomal Recessive Deafness 9: a single-arm trial的文章。该研究在医院大力支持下,在耳鼻喉科研究院院长、科主任李华伟教授带领下,由复旦大学附属眼耳鼻喉科医院舒易来教授主导合作完成。研究者开发了基于腺相关病毒(adeno-associated virus,AAV) 的双载体基因置换疗法(RRG-003药物),6名因OTOF基因突变致聋的患者接受治疗,其中5名患儿获得明显的听力及言语功能改善。该研究是国际上首个遗传性耳聋基因治疗的临床试验研究(first-in-human),随访期间展示出良好的安全性和有效性,在人体首次应用双AAV克服大基因递送的难题,展现了基因治疗对治愈遗传性耳聋的应用潜力,极大地推动了基因治疗领域的发展,开启了耳聋基因治疗新时代。

随着生物医药技术的革新和发展,基因治疗被认为是根治遗传性耳聋最有潜力的策略之一。基因治疗是指将正常功能的基因或有治疗作用的基因通过一定方式导入靶细胞内,以纠正、替代基因缺陷或者异常,实现治疗疾病的方法。在耳聋基因治疗领域中,主要是通过腺相关病毒载体,将正常的基因或基因编辑体系递送至耳蜗细胞中表达,补偿缺陷基因功能或纠正致病突变,实现听功能的改善或恢复。

OTOF基因(表达耳畸蛋白)突变是导致先天性耳聋最常见的致病基因之一,患者通常表现为重度、极重度或完全听力损失和言语障碍。在不同人群中均发现OTOF基因的高突变携带率,在我国婴幼儿听神经病中OTOF基因突变频率高达41%。OTOF基因含有48个外显子,cDNA大小约6 kb,编码翻译含有1977个氨基酸的耳畸蛋白,主要参与毛细胞中突触囊泡上释放神经递质形成听觉的过程。OTOF基因致病突变引起常染色体隐性遗传性耳聋(Autosomal recessive deafness 9,DFNB9)。内毛细胞中耳畸蛋白表达的缺失会导致声音刺激信号无法正常传递至听觉神经通路到达大脑,而引起耳聋,并导致言语障碍。

AAV是目前最常用的内耳基因递送载体,然而OTOF cDNA超出了单个AAV的递送上限(~4.7 kb)。为克服大基因内耳递送难题,研究团队基于AAV的双载体基因置换疗法,即采用双AAV介导,由该载体携带人源性OTOF编码序列。将RRG-003经内耳注射至Otof −/−小鼠中,其听力明显得到改善。同时,团队在小鼠和猴模型中进行了安全性评估。该药物有效且耐受性、安全性好,为其临床转化提供了关键支持。

基于临床前的有效性和安全性数据,2022年6月,该项目获得复旦大学附属眼耳鼻喉科医院伦理批准,2022年10月,该团队发起全球首个遗传性耳聋基因治疗临床试验并筛选、招募受试者,随后完成了全球首例遗传性耳聋患儿的内耳基因治疗,从大龄儿童到小龄儿童,陆续纳入多例患者完成基因治疗。目前,最长的随访时间已达1年以上,患儿可进行日常对话。

该文章披露了6位OTOF突变耳聋患儿接受了RRG-003药物基因治疗,其中最大的为6岁,最小的为1岁,研究团队还自主研发了人类内耳给药装备,通过耳部微创的方式,将该药物一次注射到患者内耳,随访期间展示出良好的安全性和耐受性。随访期内,5位患儿接受治疗后听力和言语功能得到恢复或改善,并且总体效果随着随访时间的延长而更好,部分频率甚至能恢复到正常人的听力水平。

该研究为OTOF基因突变致聋患者提供了特异性的基因治疗候选药物,取得了鼓舞人心的成果,临床意义重大。该临床研究是全球第一项获得临床疗效的内耳基因治疗和双AAV载体的人体试验,也是基因治疗领域中我国在国际上取得的重大突破方向。为后续进一步开展耳聋基因治疗的临床试验注入了一剂强心针,开启了真正意义上的耳聋根治时代。本次临床突破,也是一次院企合作、利用互补优势高效推进产学研转化的尝试,眼耳鼻喉科医院选择了上海鼎新基因科技有限公司,借力公司在药物开发上的经验,打通了基因治疗药物研发、产业化设计、工艺生产、安全评估等通路,建立了产学研发展新模式,极大地推动了耳聋基因治疗的发展,为患者带来了新希望。

专家点评

审稿人评论:

“The AAV approach in this submission is a novel report of this approach to be used for the first time for cochlear gene therapy in humans. This work tries to provide the first evidence regarding safety and efficacy of AVV gene therapy for treating deafness. In this original manuscript by Lv et al., the authors seek to rescue non-syndromic autosomal recessive hereditary hearing loss (deafness 9) associated with deficiency of otorfelin. The durable therapeutic effect and drastic hearing improvement in patients strongly motivate the application of the existing AAVs for treating human deafness. The manuscript is well written, the experiments seem to be performed carefully, and the results are presented in a clear way. The presented research work is interesting. The authors should be congratulated on this important and well-executed work”

“The manuscript provided by the authors presents data of the worldwide first gene therapy treatment for sensorineural hearing loss. The study is an important contribution to the field of gene therapy and specifically to the field of otology.”

专家点评

戴朴教授(中国人民解放军总医院耳鼻咽喉头颈外科耳科主任、国家耳鼻咽喉疾病临床医学研究中心副主任、遗传性耳聋领域著名专家):

“首先,恭喜复旦大学附属眼耳鼻喉科医院舒易来教授以及李华伟教授团队在柳叶刀上发表了遗传性耳聋患者在接受基因治疗后获得显著疗效的文章。耳聋基因治疗一直是耳鼻喉科领域研究的热点,舒教授及李教授团队的这个发现,是遗传性耳聋患者临床治疗的创新和突破,使得全球的耳鼻喉科医生和患者看到了基因治疗治愈遗传性耳聋的希望,更重要的是这一临床成果将加速实现基因治疗全面应用于临床的伟大目标。”

专家点评

Konstantina Stankovic教授(美国外科学院院士、Bertarelli 教授兼主席、斯坦福大学耳鼻咽喉头颈外科系主任,听觉医学著名专家):

“It is indeed a pleasure and an honor to comment on the groundbreaking paper “AAV1-hOTOF Gene Therapy for Autosomal Recessive Deafness 9," just published in the Lancet. I believe that the critical elements of the study, such as the dual-vector gene replacement therapy and the minimally invasive micro-injections into the inner ear, have direct relevance for many future gene therapies for hearing loss. Thanks to the team’s unceasing efforts, our profession has reached this watershed moment in gene therapy when we can finally offer help to so many people in need.

I hope that it will inspire further work for the benefit of people worldwide. Congratulations again on the innovative and courageous approach, and a job well done!”

专家点评

Lawrence R. Lustig教授(哥伦比亚大学内外科医学院和纽约长老会医院/哥伦比亚大学医学中心的耳鼻咽喉头颈外科主任,兼Haward W. Smith 教授和主席,著名听力损失遗传学和耳聋基因治疗专家):

“I’d like to offer enormous congratulations to Dr. Yilai Shu and their team at Fudan University for their upcoming study to be published in the Lancet. This is really a remarkable study that restores hearing in that cohort of patients with otoferlin-related deafness. As you know, people from around the world have been working on this project for years and to finally see this come to fruition is truly wonderful. Again, huge congratulations, and job well done.”

专家点评

Mark A. Varvares教授(哈佛大学医学院耳鼻咽喉头颈外科系主任、教授):

“My name is Doctor Mark A. Varvares, the chairman of the Department of Otolaryngology-Head and Neck Surgery at the Massachusetts Eaton-Peabody laboratories and at Harvard Medical School in Boston. I want to take a few moments to congratulate this team of researchers for their work, recent publication on the use of an adeno-associated virus treatment of a genetic hearing loss related to the loss of the otoferlin gene. The results published in the Lancet are stunning and show that children affected with this genetic hearing loss treated with this approach recovered their hearing. I'd like to thank the researchers for their amazing work and to congratulate them for the work they've done that will change the lives of millions of patients around the world, as this is a very important proof of concept, a study that shows that yes, this does work, this type of gene therapy does work for genetic hearing loss. So, congratulations again. This is a very exciting day in the world of hearing research, and we look forward to further work from this group and others now built upon this work.”

复旦大学附属眼耳鼻喉科医院舒易来教授、李华伟教授、王武庆教授以及哈佛大学医学院陈正一教授、东南大学柴人杰教授为本文的共同通讯作者。复旦大学附属眼耳鼻喉科医院的吕俊博士生、王会博士、程晓婷主治医师、陈玉鑫助理研究员以及王大奇助理研究员为本文的共同第一作者。本研究得到了医院工作人员、实验室其他成员和其他合作科研团队的大力支持。

https://doi.org/10.1016/S0140-6736(23)02874-X

制版人:十一