Search

Administration of AAV-based gene therapies into the intra-cerebrospinal fluid (CSF) compartments via routes such as lumbar puncture (LP) has been implemented as an alternative to intravenous dosing to target the CNS regions. This route enables lower doses, decreases systemic toxicity, and circumvents intravascular pre-existing anti-AAV antibodies. In this study, AAV9-GFP vectors were administered via LP to juvenile cynomolgus macaques with and without pre-existing serum anti-AAV9 antibodies at a 5.0 × 10 13 vector genomes per mL (vg/mL) dose and examined for 28 days. CNS and peripheral tissues were surveyed for vector genome, mRNA, and protein expression. Histopathology, clinical pathology, and humoral immune response to the viral capsid and transgene were also assessed. In addition, serum and CSF samples were analyzed to examine 276 proteomic markers curated to evaluate neural injury, organ damage, and inflammatory response. This study reveals no noticeable difference in AAV9-mediated gene transfer in the CNS tissues in the two groups; however, differences were observed for endpoints such as liver enzyme activities, histopathology, and levels of protein markers in the serum and CSF. These findings provide a view into vector transduction efficiency and safety following LP-delivered AAV9 to juvenile cynomolgus macaques with and without pre-existing anti-AAV9 antibodies., Competing Interests: All the authors are current and past employees of Novartis Gene Therapies (G.H.G., J.D., Y.G., B.C., and F.O.) and Novartis Biomedical Research (G.H.G., F.O., R.K., and T.M.). All authors disclose salaries and compensations received for the execution of this study funded by Novartis Gene Therapies and Novartis Biomedical Research., (© 2024 Novartis AG.)

Nonclinical development strategies for gene therapies are unique from other modalities. The European Federation of Pharmaceutical Industries and Associates (EFPIA) Gene Therapy Working Group surveyed EFPIA member and nonmember pharmaceutical and biotechnology companies about their current practices for designing and implementing nonclinical toxicology studies to support the development of viral vector-delivered in vivo gene therapies. Compiled responses from 17 companies indicated that these studies had some variability in species selection, study-design elements, biodistribution, immunogenicity or genomic insertion assessments, safety pharmacology, and regulatory interactions. Although there was some consistency in general practice, there were examples of extreme case-by-case differences. The responses and variability are discussed herein. Key development challenges were also identified. Results from this survey emphasize the importance for harmonization of regulatory guidelines for the development of gene-therapy products, while still allowing for case-by-case flexibility in nonclinical toxicology studies. However, the appropriate timing for a harmonized guidance, particularly with a platform that continues to rapidly evolve, remains in question., (© 2020 The Author(s).)

Assessing the carcinogenic potential of innovative drugs spanning diverse therapeutic modalities and target biology represents a major challenge during drug development. Novel modalities, such as cell and gene therapies that involve intrinsic genetic modification of the host genome, require distinct approaches for identification of cancer hazard. We emphasize the need for customized weight-of-evidence cancer risk assessments based on mode of action that balance multiple options for preclinical identification of cancer hazard with appropriate labeling of clinical products and risk management plans. We review how advances in molecular carcinogenesis can enhance mechanistic interpretation and preclinical indicators of neoplasia, and recommend that drug targets be systematically assessed for potential association with tumorigenic phenotypes via genetic models and cancer genome resources., (Copyright © 2016 Elsevier Inc. All rights reserved.)

Inhibition of vascular endothelial growth factor (VEGF) for the management of the pathological ocular neovascularization associated with diseases such as neovascular age-related macular degeneration is a proven paradigm; however, monthly intravitreal injections are required for optimal treatment. We have previously shown that a novel, secreted anti-VEGF molecule sFLT01 delivered by intravitreal injection of an AAV2 vector (AAV2-sFLT01) gives persistent expression and is efficacious in a murine model of retinal neovascularization. In the present study, we investigate transduction and efficacy of an intravitreally administered AAV2-sFLT01 in a nonhuman primate (NHP) model of choroidal neovascularization (CNV). A dose-dependent and persistent expression of sFLT01 was observed by collecting samples of aqueous humor at different time points over 5 months. The location of transduction as elucidated by in situ hybridization was in the transitional epithelial cells of the pars plana and in retinal ganglion cells. AAV2-sFLT01 was able to effectively inhibit laser-induced CNV in a dose-dependent manner as determined by comparing the number of leaking CNV lesions in the treated versus control eyes using fluorescein angiography. Our data suggest that intravitreal delivery of AAV2-sFLT01 may be an effective long-term treatment for diseases caused by ocular neovascularization.