Refillable eye implant shows promise in Phase II study

Genentech — a member of the Roche Group — has unveiled positive results from its Phase II LADDER study, which evaluated the efficacy and safety of its investigational Port Delivery System with ranibizumab (PDS) in people with wet age-related macular degeneration (AMD).

The investigational PDS is a small, refillable eye implant that is slightly longer than a grain of rice has been designed to allow people with wet AMD to go several months without needing to visit their ophthalmologist for treatment.

In the study, most of the patients who had received the surgical implant managed to go six months or longer before needing a refill. The outcomes of those with the device with high doses of ranibizumab were found to be similar to patients who are administered with monthly injections and these results were maintained throughout the study period.

“If the PDS is successful, it could have a major impact on the way we treat people with wet AMD,” saidDr Carl D. Regillo, FACS, chief of Retina Service at Wills Eye Hospital in Philadelphia, Pennsylvania, USA and investigator for the LADDER study. “I believe that more consistent treatment could allow for better long-term vision outcomes in clinical practice.”

The current standard of care for patients with wet AMD is to receive regular (sometimes even monthly) injections of anti-vascular endothelial growth factor (VEGF) therapy in order to maintain gains and/or prevent vision loss. As these injections are administered by an ophthalmologist or healthcare professional it requires the patient to visit their healthcare provider each time, which is burdensome and can be related to poor adherence and as such poor visual outcomes.

“LADDER is the first successful Phase II study of a long-acting delivery device for the treatment of wet AMD. We are highly encouraged by these results and the potential of the PDS, our first implantable, drug delivery programme,” addedDr Sandra Horning, chief medical officer and head of Global Product Development. “With the PDS, we have an opportunity to make a positive impact by helping to potentially eliminate the burden of frequent treatments for people with wet AMD.”

In the study, patients who were implanted with the PDS either received 10 mg/mL, 40 mg/mL or 100 mg/mL of ranibizumab. For those patients who had the implant with the highest concentration of ranibizumab, about 80% could go six months or longer without a refill. For those on lower concentrations of ranibizumab the proportion of patients who were able to go for six months or longer before a refill was required was slightly lower at 71.3% and 63.5% for 40mg/mL and 10 mg/mL, respectively.

Secondary endpoints of the study included assessments of vision and anatomic outcomes when compared to monthly intravitreal ranibizumab 0.5 mg injections. Patients in the PDS 100 mg/mL arm achieved similar gains in Best Corrected Visual Acuity (BCVA) and similar reductions in central retina thickness compared to patients receiving monthly ranibizumab 0.5 mg injections.

The implant itself is refilled using a customised needle in a minimally invasive office-based procedure.

These results will be used to determine the most appropriate dose and fixed treatment interval to study in the Phase III programme to sustain optimal vision outcomes in clinical practice for patients with wet AMD. The clinical development programme for the Phase III trial is expected to begin later on in the year.