Glaucoma is the second most common cause of blindness worldwide. It is estimated that 4.5 million people globally are blind due to glaucoma and that this number will rise to 11.2 million by 2020. Up to 50% of affected persons in the developed countries are not even aware they have glaucoma. This number may rise to 90% in underdeveloped parts of the world. The most common type of adult-onset glaucoma is Primary Open Angle Glaucoma (POAG) Prevalance Rate: approx 1 in 90 or 1.10% or 3 million people in USA Undiagnosed prevalence rate: approx 1 in 272 or 0.37% or 1 million people in USA.

IOP is regulated by a fine balance between production of aqueous humour through the ciliary epithelium and drainage via the trabecular meshwork, canal of Schlemm, and uveoscleral outflow routes. Corticosteroids may regulate this process; all patients with POAG or normal tension glaucoma develop raised IOP after topical steroid therapy and raised IOP is also a recognized feature of Cushing’s syndrome. Human ciliary epithelial cells express 11βHSD1 but not 11βHSD2 and in the aqueous humor (AH), concentrations of cortisol exceed those of cortisone (14:1 ratio). Inhibition of 11βHSD1 will lower cortisol levels in the AH and improved IOP.