REGENXBIO Inc. announced additional positive data from the ongoing Phase II ALTITUDE® trial of ABBV-RGX-314 for the treatment of diabetic retinopathy (DR) without center-involved diabetic macular edema (CI-DME) using in-office suprachoroidal delivery. The data will be presented at the American Academy of Ophthalmology meeting in San Francisco, CA by Mark Barakat, M.D., Retinal Consultants of Arizona. ABBV-RGX-314 is being investigated as a potential one-time gene therapy for the treatment of wet age-related macular degeneration, DR, and other chronic retinal conditions.

ALTITUDE is a multi-center, open-label, randomized, controlled, dose-escalation trial evaluating the efficacy, safety and tolerability of suprachoroidal delivery of ABBV-RGX-314 using the SCS Microinjector® in patients with moderately severe or severe non-proliferative diabetic retinopathy (NPDR) or mild proliferative diabetic retinopathy (PDR). Patients in Cohort 1 received ABBV-RGX-314 at a dose level of 2.5x1011 genomic copies per eye (GC/eye) (dose level 1). Patients in Cohorts 2 and 3 received ABBV-RGX-314 at an increased dose level of 5x1011 GC/eye (dose level 2).

Patients in Cohorts 1-3 did not receive prophylactic corticosteroid therapy before or after administration of ABBV-RGX-314. As of September 25, 2023, ABBV-RGX-314 was reported to be well tolerated at dose levels 1 and 2. Seven serious adverse events were reported, none of which were considered drug related. For patients in dose levels 1 and 2 (n=50), common ocular treatment-emergent adverse events in the study eye through one year included conjunctival hemorrhage and conjunctival hyperemia.

Three patients had mild intraocular inflammation (IOI), which resolved on topical corticosteroids. Six patients had mild to moderate episcleritis and have resolved on topical corticosteroids. No cases of chorioretinitis, vasculitis, occlusion, or hypotony were reported.

Best Corrected Visual Acuity remained stable through one year. At one year, dose level 2 in NPDR patients prevented disease progression as measured by the Early Treatment Diabetic Retinopathy Study-Diabetic Retinopathy Severity Scale (DRSS). Importantly, dose level 2 reduced the risk of developing vision-threatening events by 89% in these patients.

NPDR patients treated with ABBV-RGX-314 at dose levels 1 and 2 demonstrated clinically meaningful improvements in disease severity and reduction of vision-threatening events. In dose level 2, patients with baseline NPDR: 100% demonstrated stable to improved disease severity. 70.8% achieved =1 step improvement vs.

25.0% in control. 0% worsened =2 steps vs. 37.5% in control.

4.2% developed vision-threatening events vs. 37.5% in control.