Purpose: The purpose of this study was to report the impact of component-level changes and manufacturing process improvements on septum durability in the ocular implant of the Port Delivery Platform (PD-P), more commonly known as the Port Delivery System with ranibizumab (PDS) with its current formulation.
Methods: Laboratory tests were conducted to determine (1) the bond strength of the septum to the overmold, (2) the amount of force utilized for the refill needle to puncture the septum, and (3) septum durability over 50 years. To simulate multiple refill-exchanges over long-term clinical use, implants were aged at elevated temperature in saline and the septum was repetitively punctured at random locations using the refill needle every 3.5 days, simulating 6 months of use.
Results: Updates to the septum-overmold interface of the implant and manufacturing process improvements doubled the bond strength between the overmold and septum (1.2 N to 2.4 N). Light lubrication of the refill needle reduced needle insertion force into the septum by >50% (1 N to 0.4 N). Together, these modifications increased long-term septum durability, with no septum dislodgements being observed after over 50 years of simulated use.
Conclusions: Structural updates to the PD-P implant and refill needle have met and exceeded performance specifications, mitigating the risk of future septum dislodgement in the updated product.
Translational relevance: Structural updates to the PD-P implant and refill needle resulted in the ability to withstand the equivalent of over 50 years of simulated use without septum dislodgement and should improve the longevity of the device in clinical use.