The use of complement inhibitors to treat geographic atrophy (GA) has its benefits and drawbacks, according to a debate at the American Academy of Ophthalmology (AAO) 2026 annual meeting. Diana V. Do, MD, vice chair of clinical affairs and professor of ophthalmology at the Byers Eye Institute at Stanford University, argued in favor of using complement inhibitors, citing their ability to slow the progression of GA by 21% through monthly treatment.
Do noted that GA is not slowing down, and figuring out how to address the increased incidence is necessary. The FDA has approved 2 complement inhibitors, pegcetacoplan and avacincaptad pegol, which can be used to treat GA. She emphasized that the slowing of progression can help patients preserve their vision longer, keeping their independence and quality of life intact.
Benefits of Complement Inhibitors
Do also addressed counterarguments, including that visual acuity did not improve. She reiterated that the medication seeks to preserve what the patient has rather than resuscitate any vision. Patients displayed a higher incidence of exudative age-related macular degeneration (AMD) and 1 in 4000 injections led to vasculitis. However, the incidence of vasculitis has diminished over time, addressing some safety concerns.
Do concluded that considering complement inhibitors for some patients can slow the progression of GA, keeping some of the retina and preserving some of the vision function. She acknowledged that it’s not perfect but is an option worth considering.
Counterarguments to Complement Inhibitors
Jennifer I. Lim, MD, a UIC distinguished professor of ophthalmology at the University of Illinois at Chicago, presented the counterargument, stating that she would not recommend the use of complement inhibitors at this time. Lim noted that the Age-Related Eye Disease Study (AREDS) found that the Mediterranean diet and other types of treatment can safely achieve similar reductions in GA growth rate toward the foveal center.
Lim pushed back on Do’s presentation, noting that complement inhibitors do not restore vision and the risks outweigh the benefits for use in GA specifically. AREDS1 Rx and AREDS2 Rx slowed the rate of progression in GA by 36% and 35%, respectively, exceeding that of complement inhibitors. The Mediterranean diet also slowed the rate of GA progression, with a hazard ratio of 0.71.
In the middle of the debate, it is clear that the use of complement inhibitors in GA treatment requires careful consideration of the pros and cons. For patients, this means weighing the potential benefits of slowed progression against the risks of increased conversion to wet AMD, endophthalmitis, and severe visual acuity loss due to retinal vasculitis. As Lim noted, the majority of GA patients are not treated with complement inhibitors, and many physicians are uncertain about their benefit or do not believe they alter outcomes.
Lim concluded that she does not recommend complement inhibitors for GA at this time, citing the AREDS and the Mediterranean diet as safer alternatives that can achieve similar reductions in GA growth rate. The audience ultimately agreed with Lim in a vote taken by applause, but a considerable number of physicians voted on the pro side as well.
Eye doctors should continue to use their best judgment and discuss options with their patients before starting treatment, as all methods demonstrate their own pros and cons. The American Academy of Ophthalmology provides resources and information on geographic atrophy and its treatment options.