Benzinga | Oct 1, 2021 03:48PM EDT

REGENXBIO Presents Initial Data from Phase II AAVIATE Trial of RGX-314 for the Treatment of Wet AMD Using Suprachoroidal Delivery and Provides Trial Update at Retina Society 54th Annual Scientific Meeting

* Suprachoroidal delivery of RGX-314 well tolerated in 50 patients in Cohorts 1-3 with no drug-related serious adverse events

* Positive initial data from Cohort 1 at six months after one-time treatment of RGX-314 Treatment effect observed with stable visual acuity and retinal thickness Demonstrated meaningful reduction in anti-VEGF treatment burden

* Phase II trial expanded to include third dose level of RGX-314 (1x1012 GC/eye)

* Company to host conference call and webcast on Friday, October 1 at 5:00 p.m. ET, featuring wet AMD Key Opinion Leaders Nikolas London, M.D., and Peter Campochiaro, M.D.

REGENXBIO Inc. (NASDAQ:RGNX) today announced initial data from the ongoing Phase II AAVIATE(r) trial of RGX-314 for the treatment of wet age-related macular degeneration (wet AMD) using in-office suprachoroidal delivery. The data is being presented at the Retina Society 54th Annual Scientific Meeting by Nikolas London, M.D., M.S., F.A.C.S., Partner and Director of Research, Retina Consultants of San Diego, Chief of Ophthalmology, Scripps Memorial Hospital. RGX-314 is a potential best-in-class, one-time gene therapy for the treatment of wet AMD.

"We are pleased to share initial data from the Phase II AAVIATE trial, and we are encouraged by the emerging clinical profile of RGX-314 for the treatment of wet AMD using suprachoroidal delivery, a delivery mechanism which we believe could provide access to gene therapy treatment in all settings of patient care," said Steve Pakola, M.D., Chief Medical Officer of REGENXBIO. "The observed stability of visual acuity and retinal thickness in the backdrop of reduced anti-VEGF injections is encouraging at this first dose level. We look forward to further enhancing our understanding of the potential of RGX-314 when delivered to the suprachoroidal space, as we continue to evaluate two higher dose levels in this trial."

"These are the first data ever reported from a gene therapy delivered to the suprachoroidal space of the eye in a clinical trial," said Dr. London. "The data from patients in Cohort 1 at six months after RGX-314 administration demonstrate the potential benefit of one-time administration of RGX-314 to the suprachoroidal space for the treatment of wet AMD. I look forward to seeing additional data from the AAVIATE trial."

Study Design and Safety Update from 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 an increased dose level of 5x1011 GC/eye versus monthly 0.5 mg ranibizumab intravitreal injection at a 3:1 ratio. Cohort 3 is designed to evaluate RGX-314 at the same dose level as Cohort 2 in 20 patients who are neutralizing antibody (NAb) positive. Patients in all three cohorts did not receive prophylactic immune suppressive corticosteroid therapy before or after administration of RGX-314. Enrollment is complete across these three cohorts.

As of September 13, 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

Summary of Data for Cohort 1 at Six Months

Fourteen patients dosed with RGX-314 in Cohort 1 demonstrated stable visual acuity at six months with a mean Best Corrected Visual Acuity (BCVA) change of -2.8 letters (95% Confidence Interval: -7.0, 1.4) when measured from Day 1 (at Screening) and -0.6 letters (-5.2, 4.0) when measured from Week 1 (prior to Randomization). These patients also demonstrated stable central retinal thickness (CRT), with a mean change of -2.5 ?m (-27.1, 22.0) at six months from Day 1. Five patients receiving monthly injections of ranibizumab had a mean BCVA change at six months of +6.8 letters (-3.3, 16.9) when measured from Day 1 and +3.0 letters (-4.7, 10.7) when measured from Week 1. Patients receiving monthly injections of ranibizumab also demonstrated stable CRT, with a mean change of -22.2 ?m (-41.6, -2.8) 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 1 received a mean of 1.2 injections over six months following administration of RGX-314, which represents a 75.9% reduction in anti-VEGF treatment burden. Four out of fourteen patients 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 +1.3 letters (-5.7, 8.2), and a mean change of CRT of -5.8 ?m (-49.5, 38.0).

As of September 13, 2021, among patients in Cohort 1 dosed with RGX-314, common treatment emergent adverse events (TEAE) in the study eye were generally mild, and none were severe. These included conjunctival hemorrhage, worsening of wet AMD, conjunctival hyperemia, and dry eye. In addition, mild intraocular inflammation was observed in four out of 15 patients based on slit-lamp examination. All cases were resolved within days to weeks on topical corticosteroids, which have been discontinued.

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

AAVIATE Trial Expansion to Dose Level 3

REGENXBIO announced today that the AAVIATE study has expanded, and two additional cohorts (Cohorts 4 and 5) will be enrolled 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. As in previous cohorts, patients will not receive prophylactic immune suppressive corticosteroid therapy before or after administration of RGX-314.

Conference Call

In connection with this announcement, REGENXBIO will host a webcast and conference call with accompanying slides today at 5:00 p.m. ET. This event will feature Nikolas London, M.D., M.S., F.A.C.S., Partner and Director of Research, Retina Consultants of San Diego, Chief of Ophthalmology, Scripps Memorial Hospital, and Peter Campochiaro, M.D., Director, Retinal Cell and Molecular Laboratory, Professor of Ophthalmology, The Wilmer Eye Institute, The Johns Hopkins University School of Medicine.

To access a live or recorded webcast of the call and accompanying slides, please visit the "Investors" section of the REGENXBIO website at www.regenxbio.com. To access the live call by phone, dial (855) 422-8964 (domestic) or (210) 229-8819 (international) and enter the passcode 4577338. The recorded webcast will be available for approximately 30 days following the call.