Beyond the injection: delivery systems reshaping retinal disease management

Intravitreal injections remain the standard for treating common retinal diseases including age-related macular degeneration (AMD), diabetic macular edema (DME) and diabetic retinopathy. However, frequent administration creates significant treatment burden due to limited drug half-life and the chronic nature of these conditions.

This review summarizes emerging drug delivery techniques and therapies for retinal disease that have achieved FDA approval within the past five years or have advanced to Phase 3 development, including intravitreal sustained-release platforms and alternative delivery routes (suprachoroidal, subretinal, topical, and subcutaneous). Specific innovations discussed include the ranibizumab port delivery system, EYP-1901 (Duravyu, vorolanib implant), KSI-301 (tarcocimab tedromer), KSI-501, OTX-TKI (Axpaxli, axitinib implant), 4D-150, revakinagene taroretcel-lwey (Encelto, NT-501, encapsulated cell therapy), Xipere (triamcinolone acetonide injectable suspension), AU-011 (belzupacap sarotalocan targeted delivery), ABBV-RGX-314, elamipretide, and OCS-01 (high concentration dexamethasone).

Promising innovations include sustained-release intravitreal implants, topical and subcutaneous delivery systems, and targeted methods like suprachoroidal and subretinal injections, each with unique advantages and limitations. Challenges include overcoming the blood-retinal barrier, surgical complications with implantable devices, and ensuring patient adherence. Advances in smart delivery systems, drug formulations, and predictive models, alongside interdisciplinary collaboration, will be crucial in achieving personalized, effective, and sustainable retinal therapies.