Diagnosis and design of clinical trials hampered by difficulties identifying signs and symptoms of dry eye

This was a review and interpretation of the literature on dry eye disorders (DED) to identify opportunities for improving diagnosis and disease management and for developing new, effective therapies.

Diagnosis of DED and the design of clinical trials for new drugs have been hampered by a lack of correlation between signs and symptoms, as well as difficulty meeting FDA criteria for primary efficacy endpoints. Successful new drug applications will likely require new approaches such as the use of objective biomarkers for disease severity.

A principal problem encountered in all clinical trials for dry eye is the placebo effect of artificial tears on outcomes. The DEWS report suggests that substituting a ‘no treatment' arm for a placebo arm may be indicated.

Other innovative approaches to clinical trials include harnessing the short-term environmental effects on surface staining by controlling the environment itself; refining traditional endpoints such as staining to the central cornea, which has an effect on vision; and studying variability in the general population versus dry eye patients to document variation in presentation.

As new information about dry eye becomes available, designs for clinical trials undoubtedly will undergo further evolution. This is critical to surmount the regulatory barriers to successful development of new, efficacious treatment options.

Financial Disclosures
Dr. Sheth has no financial interests to disclose.