The purpose of this study is to characterize emixustat hydrochloride pharmacokinetic and pharmacodynamic parameters in subjects with geographic atrophy associated with dry age-related macular degeneration.

This is a multi-center, randomized, masked, multiple-dose, crossover study of the pharmacokinetics of emixustat hydrochloride (HCl) in subjects with geographic atrophy (GA) associated with dry age-related macular degeneration (AMD). Subjects will receive study drug during multiple dose periods in a crossover design, and serve as their own controls. There is a 21-28 day washout period between dose periods. The final Study Exit visit is 21 to 28 days after the subject's last dose of study drug at the end of the final dosing period.

Inclusion Criteria:

• Males or females age ≥65 years
• Clinical diagnosis of GA associated with AMD
• Able and willing to provide written informed consent
• Able to reliably administer oral medication by self or with available assistance

Exclusion Criteria:

• Geographic atrophy associated with a condition other than AMD
• History of, active or high risk of developing choroidal neovascularization (CNV) in either eye
• Known serious allergy to the fluorescein sodium for injection in angiography
• Pre-specified laboratory abnormalities at screening
• Treatment with any investigational study drug within 30 days of screening or device within 60 days of screening
• Prior participation in any clinical study of emixustat
• History of other disease, metabolic dysfunction, chronic immunosuppression, physical examination finding
• Male subjects who are not surgically sterile and are not willing to practice a medically accepted method of birth control with their female partner of childbearing potential from screening through 21 days after the last dose of study drug