This multicenter open-label extension study is designed to evaluate the safety and tolerability of lampalizumab intravitreal injections in participants with GA secondary to age-related macular degeneration (AMD) who completed 96 weeks of treatment in Studies GX29176 (NCT02247479) or GX29185 (NCT02247531). The extension will enroll participants from the parent studies who received investigational lampalizumab, as well as lampalizumab-naive participants exposed to sham comparator. All participants will receive open-label lampalizumab in the present study.