Port Delivery System with ranibizumab: Maintenance of vision with reduced treatment burden

Reviewed by Dr Carl Regillo

The Port Delivery System (PDS) with ranibizumab (Genentech) with dosing every 24 weeks was shown in a Phase III trial to be equivalent to monthly intravitreal ranibizumab (Lucentis, Genentech) injections to treat neovascular age-related macular degeneration (nAMD).

The device provided equivalent visual acuity outcomes and controlled retinal thickness with greater durability and reduced treatment burden, all with a favourable benefit-risk profile, according to Dr Carl Regillo, who reported on behalf of the Archway Trial investigators.

The PDS, which provides continuous intravitreal drug delivery, is a permanent, refillable intraocular implant that contains a customised, high-concentration formulation of ranibizumab.

The device is implanted surgically and is then refilled or exchanged in the clinic. 

A total of 248 patients received the PDS (100 mg/ml every 24 weeks). The primary endpoint of the Phase III study was the change in the best-corrected visual acuity (BCVA) from baseline averaged over weeks 36 and 40 after insertion.

Patients implanted with the PDS could receive a supplemental intravitreal 0.5-mg injection of ranibizumab for protocol-specific disease activity.

A total of 167 patients comprised the control group, which was treated with intravitreal ranibizumab (0.5 mg every 4 weeks).

“The PDS was found to be noninferior and equivalent to monthly ranibizumab injections when the two study groups were compared based on the average visual results at 36 to 40 weeks. The difference in the adjusted mean letter score was -0.3 letter,” Dr Regillo reported.

The PDS also maintained vision very well over 40 weeks; 80% of patients implanted with the device maintained at least 20/40 vision after recovery postoperatively.

The percentages of patients who maintained or gained vision were similar between the two groups, i.e., 58.9% for intravitreal ranibizumab and 57.8% for the PDS. The changes in the retinal thicknesses as measured by optical coherence tomography (OCT) in the two groups were also similar.

Dr Regillo reported that 98.4% of patients implanted with the device did not need supplemental ranibizumab therapy up until the time of the first mandated device refill and there were about five times fewer treatments until week 40 for these patients.

Up until week 40, the PDS group averaged two treatments compared with 10.7 treatments in the group treated monthly.

Regarding adverse events, the PDS implant insertion and the refill-exchange procedure were generally well tolerated. Notable device-related adverse events included four cases of endophthalmitis, one case of device dislocation and 13 cases of vitreous haemorrhage; all resolved spontaneously.

“The PDS inserted to treat nAMD was noninferior and equivalent for the changes in BCVA at weeks 36 and 40 and controlled the retinal thickness as well as the monthly injections up through the primary endpoint. The vast majority of patients with PDS did not need supplemental treatment and had a markedly reduced treatment burden. The PDS had a favourable benefit-risk profile,” Dr Regillo concluded.

Carl Regillo, MD, is director of the Will Eye Hospital Retina Service and professor of ophthalmology, Thomas Jefferson University, Philadelphia, United States. Dr Regillo is a consultant to Genentech.