“Δ9-Tetrahydrocannabinol-valine-hemisuccinate, a hydrophilic prodrug of Δ9-tetrahydrocannabinol, synthesized with the aim of improving the ocular bioavailability of the parent molecule, was investigated in a lipid-based nanoparticle dosage form for ocular delivery.
A peak intraocular pressure (IOP) drop of 30% from baseline was observed in rabbits treated with SLNs loaded with Δ9-tetrahydrocannabinol-valine-hemisuccinate at 90 minutes. Treated eyes of rabbits receiving Δ9-tetrahydrocannabinol-valine-hemisuccinate SLNs had significantly lower IOP than untreated eyes until 360 minutes, whereas the group receiving the emulsion formulation showed a drop in IOP until 90 minutes only. In comparison to marketed pilocarpine and timolol maleate ophthalmic solutions, Δ9-tetrahydrocannabinol-valine-hemisuccinate SLNs produced a greater effect on IOP in terms of both intensity and duration. In terms of tissue concentrations, significantly higher concentrations of Δ9-tetrahydrocannabinol-valine-hemisuccinate were observed in iris-ciliary bodies and retina-choroid with SLNs.
Δ9-Tetrahydrocannabinol-valine-hemisuccinate formulated in a lipid-based nanoparticulate carrier shows promise in glaucoma pharmacotherapy.
Glaucoma therapies usually focus on decreased aqueous humor production and increased outflow. However, such therapy is not curative, and there lies a need in preclinical research to focus efforts on agents that not only affect the aqueous humor dynamics but also provide neuroprotection. Historically, there have been bench-scale studies looking at retinal ganglion cell death post-axonal injury. However, for a smooth translation of this in vitro activity to the clinic, animal models examining IOP reduction, i.e., connecting the neuroprotective activity to a measurable outcome in glaucoma management (IOP), need to be investigated. This study investigated the IOP reduction efficacy of cannabinoids for glaucoma pharmacotherapy in a normotensive rabbit model, bringing forth a new class of agents with the potential of IOP reduction and improved permeation to the back of the eye, possibly providing neuroprotective benefits in glaucoma management.”
“THC has been demonstrated to be effective in glaucoma management, helping to lower IOP in human subjects after smoking marijuana; however, the molecule fails to manifest a similar effect when dosed topically. This research explores molecular bioengineering and formulation-based strategies to improve the ocular bioavailability of THC, facilitating the molecule to translate into a dosage form capable of demonstrating a desired IOP-lowering effect even on topical application. These studies suggest that formulation development efforts along with prodrug derivatization can effectively improve the overall ocular bioavailability of THC. Thus, THC-VHS represents a potential new therapy option for the treatment and management of glaucoma by virtue of its superiority in lowering IOP when compared to antiholinergic and beta blockers, as studied in this model.”