function. Measures of anatomic changes are already being used to support an indication of a treatment effect, but data to date suggests a poor correlation with many aspects of OCT measurements and visual acuity (Fleckenstein et al. 2010). Therefore, it is not clear how and when OCT findings will be used as a surrogate outcome for visual function. But as these new imaging modalities are further tested alternative anatomic measures, such as integrity of the inner segment/outer segment junction, may prove to be more precise predictors of visual acuity (Oster et al. 2010). The future of these more rapidly measurable endpoints portends an exciting future for the development of treatments for retinal diseases.

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Chapter 21

Druggable Targets and Therapeutic Agents for Disorders of the Back of the Eye

Robert I. Scheinman, Sunil K. Vooturi, and Uday B. Kompella

Abstract  The retina and associated supportive tissues must perform large amounts of metabolic work to effectively process visual information. Metabolic imbalances in these tissues can lead to various diseases of the back of the eye that generally involve the interplay of three major processes: inflammation, neovascularization, and degeneration. Improved understanding of these processes within the back of the eye has led to the development of a rather large number of new therapeutics over the last decade and this process shows no sign of slowing down. This chapter summarizes emerging drug targets, new drugs, and drugs undergoing clinical trials for treating various back of the eye diseases including age-related macular degeneration, diabetic retinopathy, retinopathy of prematurity, infections, and autoimmune uveitis.

21.1  Introduction

The eye is unique in a number of ways. As a sensory organ it can detect as little as three photons, transform this into a neural signal, and pass it onward into the central nervous system (CNS) (Rieke and Baylor 1998). The metabolic requirements underlying this sensitivity are huge. Indeed the retina is the most metabolically active tissue within our body. This high rate of metabolism renders the eye relatively more susceptible to a variety of insults which alter the various processes involved in generating energetic compounds and removing waste products. Unlike the skin, which blocks high energy radiation, the eye absorbs and focuses this radiation onto the retina. This can lead, over time, to the buildup of damaged proteins and reactive oxygen intermediates. The shape of each tissue within the eye is critical to eye function.

R.I. Scheinman (*)

Department of Pharmaceutical Sciences, University of Colorado, 12850 East Montview Blvd., C238-V20, Aurora, CO 80045, USA e-mail: robert.scheinman@ucdenver.edu

U.B. Kompella and H.F. Edelhauser (eds.), Drug Product Development for the Back of the Eye, 495 AAPS Advances in the Pharmaceutical Sciences Series 2, DOI 10.1007/978-1-4419-9920-7_21,

© American Association of Pharmaceutical Scientists, 2011