Regeneron Presents Encouraging Phase 2 Results for High-Dose Aflibercept 8 mg in Wet AMD

Regeneron Pharmaceuticals announced results from its phase 2 proof-of-concept trial evaluating an investigational 8 mg high dose of aflibercept compared to the currently-approved 2 mg dose of Eylea (aflibercept) Injection in patients with wet age-related macular degeneration (AMD). The results will be presented at the Angiogenesis (Angiogenesis, Exudation, and Degeneration) 2022 annual meeting on Saturday, February 12.

As previously announced, more patients treated with aflibercept 8 mg had no retinal fluid at week 16, when the primary efficacy endpoint was assessed. At this timepoint, 43% (n=23/53) had no fluid in the macula compared to 26% for Eylea (n=14/53) (P=0.0667); and 51% (n=27) had no fluid in the center subfield compared to 34% for Eylea (n=18) (p=0.0770). At week 16, patients in both treatment groups had received three initial doses (administered at weeks 0, 4 and 8), after which dosing was extended to every 12 weeks. In new results presented for the first time, aflibercept 8 mg continued to show numeric improvements in anatomical and vision outcomes compared to Eylea through 44 weeks. 

"These phase 2 data in wet AMD demonstrate the exciting potential for aflibercept 8 mg to maintain dryness and improve vision compared to the standard-of-care Eylea," David Brown, MD, Director of Research at Retina Consultants of Texas, said in a company news release. "This is the first time we have seen a promising trend towards sustained improved vision over Eylea in wet AMD. I look forward to seeing the results of the phase 3 program investigating extended dosing of aflibercept 8 mg."

Eyes treated with aflibercept 8 mg were more likely to be dry in the center subfield on optical coherence tomography (OCT) compared to Eylea at every timepoint measured throughout the trial after the initial monthly dosing period. At week 44 when the trial ended, key anatomical and vision changes included:

• 40% (n=21/53) of patients treated with aflibercept 8 mg did not have fluid in the center subfield compared to 28% (n=15/53) of patients treated with Eylea (nominal p=0.2185).
• Twice as many patients treated with aflibercept 8 mg (32%, n=17/53) had no macular fluid compared to patients treated with Eylea (15%, n=8/53) (nominal P=0.0395), as measured by spectral domain OCT. Measuring macular fluid provides an evaluation of a larger area of the retina compared to the center subfield and may provide a better understanding of the anatomical effects of treatment in wet AMD. 
• 7.9 average letter improvement from baseline in the aflibercept 8 mg group, compared to 5.1 letters in the Eylea group, as measured by Early Treatment Diabetic Retinopathy Study (ETDRS) letters (nominal P=0.1957).
• Nearly half (47%) of aflibercept 8 mg patients achieved at least a 10-letter gain (2 lines on a vision test) and more than a quarter (28%) achieved more than 15 letters (3 lines on a vision test), compared to 35% and 18% for patients treated with Eylea, respectively.

Through 44 weeks, adverse events (AEs) in the study eye occurred in 38% (n=20/53) of both aflibercept 8 mg and Eylea patients. There were no serious AEs of intraocular inflammation (including occlusive retinal vasculitis), and no anti-platelet trialists' collaboration (APTC)-defined arterial thromboembolic events. The most common ocular AEs that occurred more frequently in the aflibercept 8 mg group were vitreous detachment (4 aflibercept 8 mg, 2 Eylea), conjunctival hemorrhage (3 aflibercept 8 mg, 2 Eylea) and retinal tear (2 aflibercept 8 mg, 0 Eylea). There was one patient death in the aflibercept 8 mg unrelated to treatment.

"After more than two decades of following the science in retinal diseases, we are very proud of our legacy helping millions of patients to retain or improve their vision with Eylea, which has set a very high bar for any new treatment," George D. Yancopoulos, MD, PhD, President and Chief Scientific Officer at Regeneron, said in the news release. "The results of this phase 2 trial for aflibercept 8 mg are promising and we look forward to seeing the results from the phase 3 program, which we hope will show that aflibercept 8 mg can deliver clinical outcomes that, at a minimum, will be comparable to standard-of-care Eylea, but allow for extended dosing regimens." 

Aflibercept 8 mg is being jointly developed by Regeneron and Bayer. This new, concentrated high-dose aflibercept formulation enables a greater amount of medicine to be administered with each treatment, and could potentially extend the time between doses while retaining the efficacy and safety profile seen with Eylea. Aflibercept 8 mg is currently under clinical development and its safety and efficacy have not been fully evaluated by any regulatory authority.

About the Phase 2 Trial

The phase 2 randomized, single-masked CANDELA trial (NCT04126317) enrolled 106 treatment-naïve patients with wet AMD. The trial was designed to investigate the safety, efficacy and tolerability of aflibercept 8 mg compared to the currently-approved 2 mg dose of Eylea. Patients were randomized into two groups, with one group receiving aflibercept 8 mg (n=53) and the other group receiving Eylea (n=53). Patients in both groups received three initial intravitreal injections (weeks 0, 4 and 8), before the primary endpoint was assessed at week 16, after which dosing was extended to every 12 weeks, or more frequently if required due to persistent or worsening disease. Efficacy was assessed via the presence of retinal fluid in the center subfield on optical coherence tomography at this timepoint.

Trial participants were at least 50 years of age (mean: 77 years), mean baseline retinal thickness was 502.1 microns, and the best corrected visual acuity (BCVA) ETDRS letter score was between 24 to 78 in the study eye (mean: 59 letters). 

About the Phase 3 Clinical Program 

'There are two ongoing pivotal trials to investigate the efficacy and safety of aflibercept 8 mg versus Eylea. In diabetic macular edema (DME), Regeneron is sponsoring the phase 2/3 multicenter, randomized, double-masked PHOTON trial (NCT04429503). In wet AMD, Bayer is sponsoring the phase 3 multicenter, randomized, double-masked PULSAR trial (NCT04423718) in treatment-naïve patients. Across both trials, patients are randomized into one of three treatment groups, testing aflibercept 8 mg with dosing regimens at either 12- or 16-week intervals or Eylea with an 8-week dosing regimen.