Suprachoroidal Injection: A Novel Approach for Targeted Drug Delivery

Abstract

Treating posterior segment and retinal diseases poses challenges due to the complex structures in the eye that act as robust barriers, limiting medication delivery and bioavailability. This necessitates frequent dosing, typically via eye drops or intravitreal injections, to manage diseases, often leading to side effects with long-term use. Suprachoroidal injection is a novel approach for targeted drug delivery to the posterior segment. The suprachoroidal space is the region between the sclera and the choroid and provides a potential route for minimally invasive medication delivery. Through a more targeted delivery to the posterior segment, this method offers advantages over other routes of administration, such as higher drug concentrations, increased bioavailability, and prolonged duration of action. Additionally, this approach minimizes the risk of corticosteroid-related adverse events such as cataracts and intraocular pressure elevation via compartmentalization. This review focuses on preclinical and clinical studies published between 2019 and 2023, highlighting the potential of suprachoroidal injection in treating a variety of posterior segment diseases. However, to fully harness its potential, more research is needed to address current challenges and limitations, such as the need for technological advancements, refinement of injection techniques, and consideration of cost and accessibility factors. Future studies exploring its use in conjunction with biotech products, gene therapies, and cell-based therapies can lead to personalized treatments that can revolutionize the field of ophthalmology.

Smart molecules in ophthalmology: Hydrogels as responsive systems for ophthalmic applications

“…Suprachoroidal injections allow to by‐pass the anterior segment, therefore avoiding the risk of intravitreal injection‐induced cataracts and IOP elevation [122] . Furthermore, drug kinetics is influenced in a positive manner: higher levels of medication can reach the posterior segment due to low levels of drug diffusion resistance [122,123] . Suprachoroidal injections are performed using microneedles through the sclera, therefore classified as a minimally invasive procedure.…”

Seeing the Future: A Review of Ocular Therapy

“…The suprachoroidal delivery route provides a new and useful method for ocular therapy delivery, particularly in human patients, since it can minimize damage to the retina. The SCS is an appealing site of drug delivery because of its proximity to the choroid, a target for exudative AMD therapies, and because it is also proximal to the ciliary body, a target for anti-glaucoma treatments [119,120]. A lower drug dose can also be used to achieve the same efficacy as traditional routes of administration [120].…”

Ocular delivery of Pigment Epithelium-Derived Factor (PEDF) as a neuroprotectant for Geographic Atrophy

“…However, subretinal delivery requires specialised skills to prevent the development of a retinal detachment or macular hole. In contrast, the suprachoroidal route combines the relative ease of the intravitreal injection with the outer retinal targeting of the subretinal approach and is fast becoming a popular ocular delivery route [25,26].…”