RGX-314 one-time gene therapy for diabetic retinopathy shows promise in phase 2 study
Click Here to Manage Email Alerts
WAIKOLOA, Hawaii — A gene-based therapy, specifically designed to neutralize VEGF activity, may be the next approach to the treatment of diabetic retinopathy, with the advantage of a single suprachoroidal administration.
Anti-VEGF treatment in eyes with nonproliferative diabetic retinopathy without diabetic macular edema has shown to be effective in both the PANORAMA trial and the DRCR.net Protocol W. However, the Achilles’ heel of this treatment is the burden of multiple injections, Michael S. Ip, MD, said at Retina 2022.
RGX-314 (Regenxbio) is a novel gene therapy that uses an adeno-associated viral vector to deliver to the retinal pigment epithelium a gene that encodes a monoclonal antibody fragment design to neutralize VEGF. A one-time treatment, injected into the suprachoroidal space, should theoretically enable retinal cells to produce their own indefinite supply of anti-VEGF.
The phase 2 ALTITUDE study is evaluating RGX-314 for the treatment of DR without DME.
“The primary objective was to evaluate the proportion of patients with two or more step improvement in Diabetic Retinopathy Severity Scale (DRSS). We also looked at safety and tolerability and the need for any additional standard of care interventions,” Ip said.
In cohort 1, fully enrolled at this point, 15 patients received treatment with 2.5 × 1011 GC per eye, and five patients were kept under observation as controls. The treatment was well tolerated. Ocular adverse events, such as conjunctival hyperemia and hemorrhage, were predominantly mild and not drug related. No intraocular inflammation was observed. Best corrected visual acuity was stable at 3 months, with a mean loss of 0.4 letters in the observation group and a gain of 2.6 letters in the active treatment group.
“DRSS change at 3 months differed significantly between groups, with 0% of cases showing two or more step improvement in the observation group vs. 33% in the RGX-314 group. These outcomes compare favorably with other studies looking at the rates of DR regression with intravitreal anti-VEGF injections,” Ip said.
The ALTITUDE study is currently enrolling cohorts 2 and 3, in which a higher dose level of RGX-314 will be evaluated.
Collapse
Ip MS. Update on gene therapy for diabetic retinopathy. Presented at: Retina 2022; Jan. 15-21, 2022; Waikoloa, Hawaii.
Read more about
Click Here to Manage Email Alerts