Guiding syringe selection for intravitreal injections: injectability and stability analysis of compounded pegcetacoplan (SYFOVRE) and the broader implications for high-viscosity ophthalmic therapies

SYFOVRE, the brand name of pegcetacoplan and the first FDA-approved treatment for geographic atrophy arising from dry age-related macular degeneration, is currently available only in vial format. Consequently, it is often compounded and transferred into syringes. This study aims to identify the optimal syringe type for both storage and intravitreal injection (IVI) of medium- and high-viscosity formulations such as SYFOVRE. SYFOVRE was prepared in four syringe types and stored under refrigeration in amber bags for up to 110 days. Samples were evaluated for potency, aggregation, protein integrity, binding activity, pH, appearance, sterility, and container closure integrity. Syringe particulate contribution was examined using light obscuration. Injectability of each syringe was assessed through administration of 15 cP and 120 cP viscosity mimics into the vitreous of human cadaver eyes, and injection force was recorded over time. Pegcetacoplan remained stable across all syringe types for 110 days. The ClearJect (0.5 mL) syringe exceeded particulate safety limits as defined by USP <789>. Ophthalmic-specific syringes (Zero Residual [0.2 mL] and StaClear [0.25 mL]) required significantly lower injection forces than the BD (1 mL) and ClearJect (0.5 mL) (p < 0.0001). While all syringes preserved stability of SYFOVRE, injection force increased with higher viscosity. The borosilicate syringe (ClearJect) failed particulate testing, disqualifying it as a viable IVI option. Low-volume ophthalmic-specific syringes (Zero Residual and StaClear) demonstrated superior performance, suggesting they should be used for the safer delivery of intravitreal therapies. Notably, Zero Residual is the only IVI-indicated syringe that eliminates silicone oil–associated risks.