Benzinga | Nov 15, 2021 09:54AM EST

REGENXBIO Presents Additional Interim Data From Trials Of RGX-314 In Wet AMD And Diabetic Retinopathy Using Suprachoroidal Delivery At AAO 2021

REGENXBIO Inc. (NASDAQ:RGNX) today announced additional positive interim data from the ongoing Phase II AAVIATE(r) trial and the ongoing Phase II ALTITUDE(tm) trial of RGX-314 using in-office suprachoroidal delivery for the treatment of wet age-related macular degeneration (wet AMD) and diabetic retinopathy (DR) without center-involved diabetic macular edema (CI-DME), respectively. The results were presented at the American Academy of Ophthalmology (AAO) 2021 Annual Meeting by Robert L. Avery, M.D., Founder of California Retina Consultants and Research Foundation.

"We are pleased to share this initial data from Cohort 2 of the AAVIATE trial which provides encouraging evidence of the emerging clinical profile of RGX-314 for the treatment of wet AMD using suprachoroidal delivery. In the data reported today, RGX-314 was observed to be well tolerated in Cohort 2, with stable visual acuity and retinal thickness as well as a meaningful reduction in anti-VEGF treatment burden at six months," said Steve Pakola, M.D., Chief Medical Officer of REGENXBIO. "We look forward to providing additional updates from the program."

"These initial results from patients in Cohort 2 of the AAVIATE trial at six months after suprachoroidal administration of RGX-314 reinforce the potential impact that RGX-314 could have on the overall clinical management of patients with wet AMD," said Dr. Avery. "I am encouraged by the six-month data in Cohort 2 and look forward to reviewing further data from Cohorts 1-3 and from the higher dose level in Cohorts 4 and 5."

Study Design and Safety Update in Phase II AAVIATE Trial of RGX-314 for the Treatment of Wet AMD Using Suprachoroidal Delivery

AAVIATE is a multi-center, open-label, randomized, active-controlled, dose-escalation trial that will evaluate the efficacy, safety and tolerability of suprachoroidal delivery of RGX-314 using the SCS Microinjector(r). Twenty patients in Cohort 1 were randomized to receive RGX-314 at a dose level of 2.5x1011 genomic copies per eye (GC/eye) versus monthly 0.5 mg ranibizumab intravitreal injection at a 3:1 ratio. Twenty patients in Cohort 2 were randomized to receive RGX-314 at a dose level of 5x1011 GC/eye through two injections versus monthly 0.5 mg ranibizumab intravitreal injection at a 3:1 ratio. Cohort 3 is evaluating RGX-314 at the same dose level as Cohort 2 in 20 patients who are neutralizing antibody (NAb) positive. Enrollment is ongoing in two additional cohorts (Cohorts 4 and 5) to evaluate RGX-314 at a third dose level of 1x1012 GC/eye. Cohort 4 will enroll 15 patients who will be dosed with RGX-314 and Cohort 5 will evaluate the same dose level of RGX-314 in 20 patients who are NAb positive. Patients do not receive prophylactic immune suppressive corticosteroid therapy before or after administration of RGX-314.

As of November 4, 2021, RGX-314 was reported to be well tolerated across 50 patients dosed in Cohorts 1-3. Four serious adverse events (SAEs) were reported in four patients, all of which were considered not related to RGX-314.1 For the total group of Cohorts 1 and 2, all common treatment emergent adverse events (TEAEs) through 6 months in the study eye were mild, and included conjunctival hemorrhage, worsening of wet AMD, dry eye, episcleritis, and conjunctival hyperemia. Mild intraocular inflammation observed on slit-lamp examination was reported at similar incidence across both dose levels in Cohorts 1 and 2, with four out of 15 patients in Cohort 1 and three out of 15 patients in Cohort 2. All cases of inflammation in both cohorts were resolved within days to weeks on topical corticosteroids.

Summary of Data for Cohort 2 in Phase II AAVIATE Trial of RGX-314 for the Treatment of Wet AMD at Six Months

In Cohort 2, patients dosed with RGX-314 demonstrated stable Best Corrected Visual Acuity (BCVA) and central retinal thickness (CRT) at 6 months. Fifteen patients in Cohort 2 dosed with RGX-314 had a mean BCVA change of -0.1 letters (95% Confidence Interval: -3.8, 3.6) when measured from Day 1 (at Screening) and +0.2 letters (-2.7, 3.1) when measured from Week 1 (prior to Randomization). These patients also demonstrated stable central retinal thickness (CRT), with a mean change of -33 ?m (-71, 5) at six months from Day 1. Ten control patients receiving monthly injections of ranibizumab in Cohorts 1 and 2 had a mean BCVA change at six months of +4.0 letters (-0.5, 8.5) when measured from Day 1 and +1.3 letters (-2.2, 4.8) when measured from Week 1. Patients receiving monthly injections of ranibizumab had a mean change of CRT of -12 ?m (-33, 8) at six months from Day 1.

There was a meaningful reduction in anti-vascular endothelial growth factor (anti-VEGF) treatment burden in patients following administration of RGX-314 compared to the mean annualized injection rate during the 12 months prior to administration. Patients in Cohort 2 received a mean of 1.3 injections over six months following administration of RGX-314, which represents a 71.8% reduction in anti-VEGF treatment burden. Six out of 15 patients (40%) in Cohort 2 received no anti-VEGF injections over six months following RGX-314 administration. In these patients, visual acuity and CRT was observed to be stable from Day 1 over six months, with a mean change of BCVA of +1.0 letters (-3.8, 5.8), and a mean change of CRT of +8 ?m (-9.2, 24.2).

Summary of Visual Acuity Data for Cohort 1 in Phase II ALTITUDE Trial of RGX-314 for the Treatment of Diabetic Retinopathy at Three Months

REGENXBIO shared additional data from Cohort 1 of the ongoing ALTITUDE trial for the treatment of DR without CI-DME using in-office suprachoroidal delivery, supporting the positive initial data previously reported at the American Society of Retina Specialists (ASRS) Annual Meeting in October 2021. At three months, 15 patients dosed with 2.5x1011 GC/eye of RGX-314 demonstrated stable BCVA of +2.6 letters, while five patients in the observational control arm demonstrated stable BCVA of -0.4 letters.

Data presented today are available on the "Presentations and Publications" section of the REGENXBIO website at www.regenxbio.com.