Sustained-Release Intraocular Implants in Glaucoma: A New Paradigm for Long-Term Pressure Control
DOI:
https://doi.org/10.64784/089Keywords:
Glaucoma, intraocular pressure, sustained-release implants, ocular drug delivery, long-acting therapy, biodegradable implants, prostaglandin analogs, treatment adherence, chronic eye diseaseAbstract
Glaucoma is a chronic and progressive optic neuropathy in which sustained reduction of intraocular pressure (IOP) remains the most important modifiable factor to slow disease progression and prevent irreversible visual loss. Although topical hypotensive therapy is the standard first-line approach, its real-world effectiveness is frequently limited by poor adherence, variable drug bioavailability, and long-term tolerability issues. Long-acting implantable drug delivery systems have emerged as an alternative strategy designed to provide continuous intraocular drug exposure while reducing dependence on daily patient-administered treatment. This review synthesizes current evidence on long-acting implantable drug delivery systems for glaucoma, integrating pathophysiological rationale, technological characteristics, and clinical outcomes. High-impact peer-reviewed literature addressing sustained ocular drug delivery, biodegradable implants, and prostaglandin analog–based intraocular systems was analyzed, including experimental studies, clinical trials, and real-world data. The available evidence indicates that sustained-release intraocular implants achieve clinically meaningful reductions in IOP comparable to conventional topical therapy, with improved treatment persistence and reduced reliance on patient adherence. Dose–response analyses demonstrate effective pressure lowering across implant strengths, with a tendency toward a therapeutic plateau at higher doses, supporting individualized treatment optimization. Longitudinal findings further suggest durable IOP control over extended follow-up periods, including prolonged intervals without the need for additional IOP-lowering interventions. Overall, long-acting implantable drug delivery systems represent a significant advancement in glaucoma management by combining pharmacologic efficacy with controlled and sustained delivery, addressing key limitations of topical therapy and offering a promising complementary approach for long-term disease control in diverse international healthcare settings.
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