Results of the 2-part, 18-month GATHER1 trial suggest that avacincaptad pegol can significantly reduce the progression of geographic atrophy (GA) secondary to age-related macular degeneration (AMD) with few adverse effects.
Study design
This research represents a pivotal phase 2/3, prospective, randomized, double-masked, sham-controlled clinical trial of avacincaptad pegol (ACP) for AMD-related GA. Eligible patients were ≥50 years of age and had a non–center-involving GA lesion between 2.5 and 17.5 mm2. Baseline vision was limited to 20/25 to 20/320. Patients received intravitreal injection of ACP, a C5 inhibitor, every month for an 18-month course. In the first cohort, 77 participants were randomized 1:1:1 to receive monthly intravitreal injections of ACP 1 mg, ACP 2 mg, or sham. In the second cohort, 209 participants were randomized 1:2:2 to receive monthly ACP 2 mg, ACP 4 mg, or sham. The primary endpoint was the mean change in GA lesion growth over 18 months, as measured by fundus autofluorescence (FAF).
Outcomes
Monthly ACP treatment reduced the mean GA growth over 18 months by 28.1% for the 2-mg cohort and by 30.0% for the 4-mg cohort. Two cases of optic ischemic neuropathy were reported, one each in the 2-mg and 4-mg ACP groups. There was also a mild case of intraocular inflammation. No cases of endophthalmitis or vasculitis were seen. Macular neovascularization was more prevalent in the ACP 2 mg (11.9%) and ACP 4 mg (15.7%) cohorts than in their corresponding sham control groups (2.7% and 2.4%, respectively).
Limitations
Limitations exist in image acquisition. Although the study used color fundus photography, FAF, fluorescein angiography, and OCT, it did not include OCT angiography, which can noninvasively detect the presence of macular neovascularization. In addition, the results may not be generalizable to subfoveal lesions as only non-subfoveal lesions were included.
Clinical significance
Despite major advancements in AMD treatment, there is still a large unmet need for geographic atrophy treatment, which remains a leading cause of AMD-related central vision loss. Results of this study reinforce previous safety and efficacy findings, showing that ACP is well tolerated and that GA lesion growth was significantly reduced with both ACP 2 mg and ACP 4 mg. Results of the longer-term, phase 3 GATHER2 trial are pending.
Financial Disclosures: Dr. Courtney Crawford discloses financial relationships with Healpros, Welch Allyn, Intelligent Retinal Imaging Systems, Topcon, Alcon Laboratories, Oculus, Dutch Ophthalmic, Apellis Pharmaceuticals, Iveric Bio, Regeneron, Genentech, and Ocular Therapeutics (Consultant/Advisor).