Leveraging RNA nanotechnology for next-generation gene delivery systems

Can we built efficient gene delivery systems to target the brain? Gene therapy offers the promise to effectively revert the cause of inherited and acquired brain diseases. However, the brain is arguably the most challenging organ to target with therapeutic agents, especially large-size gene therapeutics. This is due to the existence of the blood brain barrier (BBB) - a highly selective border separating the blood circulation from the brain, formed by a continuous layer of sealed endothelial cells embedded in the capillary basement membrane. The BBB physiologically protects the neurons from neurotoxic factors present in the bloodstream, but also prevents exogenously administered medications to reach their target of action. Non-targeting brain therapies could not only result in poor efficacy of the treatment, but also in side effects due to the accumulation of toxic drugs in other organs, encumbering the life of the patient. Lipid nanoparticles were thought to cross the BBB, thanks to their charge and size by abortpion mediated endocytosis or transcytosis. But this approach failed to provide efficient delivery, testified by the lack of approved gene therapies targeting the brain.

Can we use nucleic acids as gene delivery systems to target the brain? Nucleic acids are unstable natural polymers that degrade by nucleases upon intravenous injection and thus far were considered unsuitable for use as drug delivery vehicles. Yet, they have inherent properties to accommodate spatially arranged molecules and controlled stoichiometry for precise shape and size nanoparticles, crucial for an efficient tissue and cell targeting. The new approach involves the introduction of nuclease stable RNA nanoparticles, based on Sixfold's Ltd patent portfolio for the exploitation of DNA and RNA-based nanoparticles and targeting molecules including, but not limited to, aptamers, for the delivery of selected gene therapeutics. In preliminary studies, these particles have shown to accumulate in the brain.

The research programme focuses on the assessment of the causal relationship between RNA nanoparticles charge, lipophilicity and size; to tissue/cell targeting. The nature of repetitive units (nucleotides) of nucleic acids, allows for precise design of the delivery systems in silico and prediction of the nanoparticle behaviour using Machine Learning. This offers a high degree of flexibility to create an on-demand platform for tissue targeting and reduce the physical experimentation. A toolbox of methods allowing for the nanoparticles stoichiometric characterization and biodistribution monitoring imaging will be developed. Preclinical demonstrators of the platform will be assessed thanks to the engagement of pioneering research groups working on animal models on neurodegenerative diseases including Parkinson's and Kennedy's (spinal bulbar muscular atrophy) diseases.

The project will have wide-ranging Academic, Economic & Societal impacts (no significant Environmental).

Academic
-Advances in understanding and methods:The project will elucidate the processes involved in the control over cell and tissue targeting via nucleic acid delivery systems, which remain not very well understood. To propagate the knowledge and methods, we estimate that the project will lead to two presentations at academic conferences per year (e.g.Gordon Research Conference in RNA Technology), and 2-3 publications (e.g.Nucleic Acids Research), subject to Intellectual Property considerations.
-Knowledge transfer:The project involves 3 academic collaborations (with Prof M Wood at Oxford University, Dr D Stuckley at UCL and Prof L Alvarez-Erviti at CBIR, Spain), who will provide their expertise and model systems to elevate the project and advise Dr Mylonaki. The project will help develop Dr Mylonaki's and her team's knowledge.To further leverage the wider academic community, once per year Dr Mylonaki will organise an on-site mini-symposium to discuss potential broader application of the research.

Economic
-Proof-of-concept data/New products:The project will generate data on incorporating Dr Mylonaki's novel strategies into Sixfold's PODS for optimised therapeutic safety and efficacy in the proof-of-concept CNS indications, where there are large unmet needs. These data will supplement Sixfold's preclinical data pack for commercialisation of innovation.We will investigate the feasibility of turning Dr Mylonaki's innovations into separate commercial products to be licensed for use in therapies other than PODS. These activities will likely lead to new IP, strenghtening Sixfold's business proposition.
-Increased revenue from licensing:Sixfold's business model is based on licensing of preclinical PODS assets for further clinical development to pharma/biotech companies. We estimate the direct benefit from Dr Mylonaki's project to have return on investment (ROI) >817% by 2025. This is driven by accelerated completion of preclinical testing with increased competitiveness due to higher efficacy aand pipeline extension.
-Establishment of Sixfold's CNS Department and Job Creation: Dr Mylonaki and her project will contribute to the establishment and expansion of Sixfold's CNS department. Importantly, the project will directly lead to creation of 3FTEs, and indirectly will result in estimated additional c.20FTEs by 2025.
-Knowledge transfer to and from industry players:The project will engage multiple industry players (incl. mentors from GSK & Autifony) to create a bi-directional feedback on the products, unmet needs and best industry and commercialisation practices to maximise value creation in a sustainable fashion.
-UK's economic competitiveness:With the research positioned at an innovative SME, the project will involve speedy and effective research and commercialisation activities contributing to the enhancement of UK's competitiveness in the emerging field of nucleic acid therapeutics and ATMPs.

Societal
-Outreach activities:We will work with various universities to give talks and presentations to children and students at various levels of education on the importance and benefits of Advanced Therapies and working in innovative start-ups/SMEs. We will also advocate for ATMPs adoption.
-Enhancing quality of life and health for patients (esp. neurodegenerative):Dr Mylonaki's research has the potential to increase the safety and efficacy of Sixfold's and other companies' therapeutics, with the ultimate aim of contributing to the expedited creation of better nuclei acid-based therapies for patients worldwide.E.g. UK:145k people are living with Parkinson's (2018) acc. to the CPRD, at the cost of £449mn-£3.3bn annually.
-Meeting Government priorities:The project is timely given favourable regulatory environment and addresses the UK's Grand Challenge related to the Aging Society.The project is well aligned with IUK