Human gene therapy最新文献

Fabry disease (FD) is a multisystemic lysosomal storage disorder caused by the loss of α-galactosidase A (α-Gal) function. The current standard of care, enzyme replacement therapies, while effective in reducing kidney pathology when treated early, do not fully ameliorate cardiac issues, neuropathic manifestations, and risk of cerebrovascular events. Adeno-associated virus (AAV)-based gene therapies (AAV-GT) can provide superior efficacy across multiple tissues owing to continuous, endogenous production of the therapeutic enzyme and lower treatment burden. We set out to develop a robust AAV-GT to achieve optimal efficacy with the lowest feasible dose to minimize any safety risks that are associated with high-dose AAV-GTs. In this proof-of-concept study, we evaluated the effectiveness of an rAAV9 vector expressing human GLA transgene under a strong ubiquitous promoter, combined with woodchuck hepatitis virus posttranscriptional regulatory element (rAAV9-hGLA). We tested our GT at three different doses, 5e10 vg/kg, 2.5e11 vg/kg, and 6.25e12 vg/kg in the G3Stg/GLAko Fabry mouse model that has tissue Gb3 substrate levels comparable with patients with FD and develops several early FD pathologies. After intravenous injections of rAAV9-hGLA at 11 weeks of age, we observed dose-dependent increases in α-Gal activity in the key target tissues, reaching as high as 393-fold of WT in the kidneys and 6156-fold in the heart at the highest dose. Complete or near-complete substrate clearance was observed in animals treated with the two higher dose levels tested in all tissues except for the brain. We also found dose-dependent improvements in several pathological biomarkers, as well as prevention of structural and functional organ pathology. Taken together, these results indicate that an AAV-GT under a strong ubiquitous promoter has the potential to address the unmet therapeutic needs in patients with FD at relatively low doses.

Rheumatoid arthritis (RA) is a chronic, inflammatory autoimmune disease marked by joint destruction and functional impairment. Tumor necrosis factor (TNF) plays a critical role in RA pathogenesis. Although TNF-targeting drugs are clinically effective, their need for frequent and long-term administration often results in poor patient adherence and suboptimal outcomes. This study developed a gene therapy approach using engineered adeno-associated virus (AAV) vectors to deliver an anti-TNF agent directly into the joint cavity of RA animal models. Animals receiving this therapy demonstrated sustained improvement in clinical scores, inflammatory markers, and joint tissue health. Immunofluorescence staining revealed that AAV vectors could transduce various cell types, including T cells, type A synoviocytes, and dendritic cells. Our results indicate that a single administration of this gene therapy provided long-term efficacy. This suggests that AAV-mediated anti-TNF gene therapy can offer prolonged relief from clinical symptoms and reduce inflammatory damage in a mouse model of RA. This innovative approach presents a promising new therapy with significant clinical prospects to treat patients with RA.

Effective use of adeno-associated viruses (AAVs) for clinical gene therapy is limited by their propensity to accumulate in and transduce the liver. This natural liver tropism is associated with severe adverse events at the high doses that can be necessary for achieving therapeutic transgene expression in extrahepatic tissues. To improve the safety and cost of AAV gene therapy, capsid engineering efforts are underway to redirect in vivo AAV biodistribution away from the liver toward disease-relevant peripheral organs such as the heart. Building on previous work, we generated a series of AAV libraries containing variations at three residues (Y446, N470, and W503) of the galactose-binding pocket of the AAV9 VP1 protein. Screening of this library in mice identified the XRH family of variants (Y446X, N470R, and W503H), the strongest of which, HRH, exhibited a 6-fold reduction in liver RNA expression and a 10-fold increase in cardiac RNA expression compared with wild-type AAV9 in the mouse. Screening of our library in a nonhuman primate (NHP) revealed reduced performance of AAV9 and two closely related vectors in the NHP liver compared with the mouse liver. Measurement of the galactose-binding capacity of our library further identified those same three vectors as the only strong galactose binders, suggesting an altered galactose presentation between the mouse and NHP liver. N-glycan profiling of these tissues revealed a 9% decrease in exposed galactose in the NHP liver compared with the mouse liver. In this work, we identified a novel family of AAV variants with desirable biodistribution properties that may be suitable for targeting extrahepatic tissues such as the heart. These data also provide important insights regarding species- and tissue-specific differences in glycan presentation that may have implications for the development and translation of AAV gene therapies.

Lipid nanoparticles (LNPs) are the most clinically advanced drug delivery system for nucleic acid therapeutics, exemplified by the success of the COVID-19 mRNA vaccines. However, their clinical use is currently limited to hepatic diseases and vaccines due to their tendency to accumulate in the liver upon intravenous administration. To fully leverage their potential, it is essential to understand and address their liver tropism, while also developing strategies to enhance delivery to tissues beyond the liver. Ensuring that these therapeutics reach their target cells while avoiding off-target cells is essential for both their efficacy and safety. There are three potential targeting strategies-passive, active, and endogenous-which can be used individually or in combination to target nonhepatic tissues. In this review, we delve into the recent advancements in LNP engineering for delivering nucleic acid beyond the liver.

MicroRNAs (miRNAs) are crucial regulators of gene expression involved in various pathophysiological processes. Their ability to modulate multiple pathways simultaneously and their involvement in numerous diseases make miRNAs attractive tools and targets in therapeutic development. Significant efforts have been made to advance miRNA research in the preclinical stage, attracting considerable investment from biopharmaceutical companies. Consequently, an increasing number of miRNA-based therapies have entered clinical trials for both diagnostic and therapeutic applications across a wide range of diseases. While individual miRNAs can regulate a broad array of mRNA targets, this also complicates the management of adverse effects seen in clinical trials. Several candidates have been discontinued due to toxicity concerns, underscoring the need for comprehensive risk assessments of miRNA therapeutics. Despite no miRNA-based strategies have yet received approval from regulatory agencies, prominent progress in the miRNA modulation approaches and in the nano-delivery systems have been made in the last decade, leading to the development of novel safe and well-tolerated miRNA drug candidates. In this review, we present recent advances in the development of miRNA therapeutics currently in preclinical or clinical stages for treating both rare genetic disorders and multifactorial common conditions. We also address the challenges related to the safety and targeted delivery of miRNA therapies, as well as the identification of the most effective therapeutic candidates in preclinical and clinical trials.