Overview of Intracameral Drug Delivery Systems in Glaucoma

Glaucoma is the leading cause of irreversible blindness worldwide, and intraocular pressure (IOP) remains the only proven modifiable risk factor for slowing disease progression. Although topical medications are the standard first-line therapy, their effectiveness is limited by poor adherence and low ocular bioavailability. These limitations have prompted the development of non-topical drug delivery systems (DDSs) that aim to provide consistent long-term IOP control without reliance on patient-administered drops. Among these approaches, intracameral DDSs have received increasing attention for their ability to deliver medication directly to the anterior chamber. This review aims to provide clinicians with an overview of the design, clinical performance, and key considerations of the two FDA-approved intracameral implants, Durysta^® (BimSR) and iDose^® TR (iDose), as well as investigational devices including ENV515, OTX-TIC, and PA5108. Currently, clinical trials indicate that these devices can achieve sustained reductions in IOP with efficacy comparable to topical prostaglandins (PGA), and real-world studies similarly report reductions in both IOP and medication burden. However, several limitations remain, including concerns about corneal endothelial cell loss (CECL), variability in treatment response among patients with more advanced disease, and the limited availability of long-term safety and durability data. In addition, randomized comparative studies evaluating intracameral DDSs against other glaucoma interventions, such as minimally invasive glaucoma surgery (MIGS), are scarce. Intracameral DDSs represent a developing area within glaucoma management, and further evidence is needed to clarify their long-term safety and their appropriate role within personalized treatment strategies.