Local delivery of vectorized anti-TNF-alpha antibodies as a treatment for Non-Infectious Uveitis

Abstract

Purpose : Uveitis comprises a heterogenous group of inflammatory intraocular diseases that can result in vision loss. Non-infectious uveitis (NIU) of the posterior segment of the eye can be difficult to treat, requiring long-term systemic immunosuppression associated with significant side effects. Here we demonstrate that adeno-associated virus (AAV) can be used to safely deliver an anti-TNF-α single chain antibody fragment to the eyes of mice and non-human primates (NHPs), and that local inhibition of TNF-α is sufficient to suppress inflammation in the mouse Experimental Autoimmune Uveitis (EAU) model.

Methods : Vectorized TNF-α inhibitors were evaluated in multiple formats (TNFR fusion proteins; IgG, Fab, and single chain antibody) and protein expression was initially screened in 293T or ARPE-19 cells. TNF-α inhibition activity in multiple species was then tested using either L929, HEK-blue, or human iPSC-derived RPE cells. Mouse ocular disease models included either the B10.RIII EAU model or an AAV-human-TNF-α overexpression model. Disease progression was assessed using optical coherence tomography and fundus imaging, and ocular function was examined with electroretinography or optokinetic tracking. Following final in vivo assessments, eyes were collected and examined for histopathology or transgene expression. Potential lead vectors were also tested in cynomolgus macaques in a 4-week tolerability study using subretinal delivery.

Results : Following disease induction, mice receiving either vehicle or control vector demonstrated a robust increase in ocular inflammation as indicated by high clinical scores, increased infiltration of inflammatory cells, and reduced ocular function. In diseased mice expressing TNF-α inhibitors, we observed a dose-dependent reduction in inflammation severity and an improvement in visual acuity. The lead vector expressing a single chain variable antibody fragment was well tolerated in NHP and demonstrated dose-dependent transgenic protein expression in ocular tissues.

Conclusions : These data show that local AAV-mediated inhibition of TNF-α in mouse eye successfully limits inflammation associated with uveitis and support further pre-clinical development of a vectorized therapeutic approach to the treatment of non-infectious uveitis.

This abstract was presented at the 2024 ARVO Annual Meeting, held in Seattle, WA, May 5-9, 2024.