(T1330-12-77) Delivery of Therapeutic Plant-Derived Exosomes to the Brain for the Treatment of Mental Health Disorders and CNS Injuries

Purpose: Mental health, traumatic brain injuries (TBI), and addictive disorders affect more than 1 billion people globally. Within this space, disorders such as treatment-resistant depression, TBI, and post-traumatic stress disorder [PTSD] are inadequately treated, resulting in chronic disorders, continued loss of productivity, and increased individual suffering. To address these, EriVan Bio is developing the next-generation natural nanoparticle delivery system for cannabinoids and other drug compounds called exosomes. An extracellular vesicle (EV), including exosomes, are nanoscale membrane-enclosed lipid particles implicated in intercellular communication by facilitating the transport of proteins and genetic material. Cannabinoids have long been used for their remedy of ailments such as cancer chemotherapy-associated symptoms. For central nervous system (CNS) therapeutic purposes, crossing the blood-brain barrier to reach the brain and obtaining therapeutic concentrations, patients are required to consume relatively high doses of cannabinoids orally daily. This is challenging for several reasons like systemic distribution and accumulation adversely affect cardiovascular. To avoid these problems in CNS therapy, cannabinoids may be delivered intracranially, an invasive and traumatic procedure. To address these concerns of intracranial administration of cannabinoids, our approach of EriVan Bio is innovative in that the nano-packaging of one or more cannabinoids into hemp-derived exosomes employs a targeted, local, and noninvasive intranasal delivery strategy to cross the BBB and reach the brain. This delivery platform reduces the overall administered dose of cannabinoids and their undesirable side effects while maintaining or enhancing cannabinoids' effects on CNS disorders and TBI.

Methods: To address current challenges in drug delivery to the brain for treating TBI and PTSD, EriVan is developing a platform of natural nanoparticle delivery vehicles to dose therapeutic compounds directly to the brain by crossing the intact blood-brain barrier (BBB). In this study, we tested the ability of hemp-derived exosomes to deliver drugs to the brain and treat TBI in mouse models. Floral parts of fresh hemp plants were juices and subjected to a series of centrifugation, filtration, and ultracentrifugation steps to harvest the plant-derived exosomes. C57/B6 mice were orally gavage or intranasally administered labelled drug-loaded hemp-derived EV, vehicle, free drug in PBS, or PBS. At varying timepoints, after treatment, animals were killed, brains were removed, imaged, and the drug content analyzed with Linear Ion Trap Quadrupole LC-MS/MS. TBI was induced using a unilateral fluid percussion injury (FPI) model. The animals were treated with either 10 μl of PBS or hemp EVs one hour after injury, twice daily for 7 days to be analyzed for GFAP and Spectrin protein levels and levels of inflammatory cytokine profiles.

Results: Our approach uses plant-derived exosomes containing and delivering the drug via an intranasal mist. Our results have shown that CBD-A, CBG-A, THC-A, CBD, and THC represent 69.1 ± 2.1%, 19.1 ± 1.6%, 6.5 ± 0.54%, 4.75 ± 0.26%, and 0.5 ± 0.3% of the total cannabinoids in our hemp EVs. We have shown physiologically meaningful concentrations of the exosomes and their drugs in the brain using intranasal delivery that resulted in a 5-fold increase in drug concentrations (CBDa) in the brain compared to CBDa in PBS, with both being administered intranasally. The labelled hemp EVs are found scattered throughout the brain hemispheres. After oral delivery, the percentage of CBDa or THCa in the brain (ng/mg of tissue/dosage) demonstrates that the plant EV has a 7.5 - 43-fold increase in CBDa brain penetration over Tween-80 or vegetable oil vehicles, respectively. We demonstrated their impact on attenuating brain injury's harmful effects through the reduction of inflammation and a significant reduction in IBA-1 in a TBI model. Additionally, a significant reduction in GFAP and Spectrin protein levels is seen in the plant EV-treated TBI animals. Inflammatory cytokine analysis using (VPLEX proinflammatory panel (Mesoscale Diagnostics)) at 24 hours, 72 hours, and 7- and 10-days post injury reveal that plant EVs significantly increase anti-inflammatory cytokines at 72 hours for IL-4 & IL-10. Hence, intranasal delivery of drugs using plant and/or stem cell-derived exosomes is feasible and provides a direct and better-controlled approach to getting drugs into the brain.

Conclusion: Given the ability to both bioengineer the hemp plant for enriched production of certain cannabinoids or harvest EVs from different hemp cultivars, plant-derived exosomes provide a cannabinoid delivery system that can be used to treat conditions such as concussion, TBI, PTSD, and degenerative diseases. Within EriVan’s pipeline of exosome-based products, we can isolate exosomes from different sources, load the natural nanoparticles with drugs, and deliver these across the BBB via intranasal delivery. In addition, we demonstrated that plant EVs are more efficient vectors than delivery with other methods and showed an improvement in the efficacy of intranasal delivery and oral delivery when using plant EVs. The significant unmet need in the mental health space is the initial clinical direction for EriVan, focusing on providing a better delivery system for treating conditions such as PTSD and TBI.