Preclinical evaluation of the efficacy and safety of AAV1-hOTOF in mice and nonhuman primates

Longlong Zhang; Hui Wang; Mengzhao Xun; Honghai Tang; Jinghan Wang; Jun Lv; Biyun Zhu; Yuxin Chen; Daqi Wang; Shaowei Hu; Ziwen Gao; Jianping Liu; Zheng-Yi Chen; Bing Chen; Huawei Li; Yilai Shu

doi:10.1016/j.omtm.2023.101154

Preclinical evaluation of the efficacy and safety of AAV1-hOTOF in mice and nonhuman primates

Mol Ther Methods Clin Dev. 2023 Nov 10:31:101154. doi: 10.1016/j.omtm.2023.101154. eCollection 2023 Dec 14.

Authors

Longlong Zhang^{1

2

3}, Hui Wang^{1

2

3}, Mengzhao Xun^{1

2

3}, Honghai Tang^{1

2

3}, Jinghan Wang^{1

2

3}, Jun Lv^{1

2

3}, Biyun Zhu^{1

2

3}, Yuxin Chen^{1

2

3}, Daqi Wang^{1

2

3}, Shaowei Hu^{1

2

3}, Ziwen Gao^{1

2

3}, Jianping Liu^{1

2

3}, Zheng-Yi Chen^{4

5}, Bing Chen^{1

2

3}, Huawei Li^{1

2

3}, Yilai Shu^{1

2

3}

Affiliations

¹ ENT Institute and Otorhinolaryngology Department of Eye & ENT Hospital, State Key Laboratory of Medical Neurobiology and MOE Frontiers Center for Brain Science, Fudan University, Shanghai 200031, China.
² Institutes of Biomedical Science, Fudan University, Shanghai 200032, China.
³ NHC Key Laboratory of Hearing Medicine, Fudan University, Shanghai 200031, China.
⁴ Department of Otolaryngology-Head and Neck Surgery, Graduate Program in Speech and Hearing Bioscience and Technology and Program in Neuroscience, Harvard Medical School, Boston, MA 02115, USA.
⁵ Eaton-Peabody Laboratory, Massachusetts Eye and Ear, 243 Charles Street, Boston, MA 02114, USA.

Abstract

Pathogenic mutations in the OTOF gene cause autosomal recessive hearing loss (DFNB9), one of the most common forms of auditory neuropathy. There is no biological treatment for DFNB9. Here, we designed an OTOF gene therapy agent by dual-adeno-associated virus 1 (AAV1) carrying human OTOF coding sequences with the expression driven by the hair cell-specific promoter Myo15, AAV1-hOTOF. To develop a clinical application of AAV1-hOTOF gene therapy, we evaluated its efficacy and safety in animal models using pharmacodynamics, behavior, and histopathology. AAV1-hOTOF inner ear delivery significantly improved hearing in Otof^-/- mice without affecting normal hearing in wild-type mice. AAV1 was predominately distributed to the cochlea, although it was detected in other organs such as the CNS and the liver, and no obvious toxic effects of AAV1-hOTOF were observed in mice. To further evaluate the safety of Myo15 promoter-driven AAV1-transgene, AAV1-GFP was delivered into the inner ear of Macaca fascicularis via the round window membrane. AAV1-GFP transduced 60%-94% of the inner hair cells along the cochlear turns. AAV1-GFP was detected in isolated organs and no significant adverse effects were detected. These results suggest that AAV1-hOTOF is well tolerated and effective in animals, providing critical support for its clinical translation.

Keywords: AAV1-hOTOF; DFNB9; dual-AAV delivery; efficacy and safety; gene therapy; hereditary hearing loss.