Elsevier

The Ocular Surface

Volume 1, Issue 1, January 2003, Pages 20-30
The Ocular Surface

Clinical Science
Gary N. Foulks, MD, section editor
Challenges and Pitfalls in Clinical Trials of Treatments for Dry Eye

https://doi.org/10.1016/S1542-0124(12)70004-6Get rights and content

Abstract

Clinical trials to evaluate the effectiveness of therapy for dry eye disease are challenging because of the nature of the disease, the multiple palliative methods used by patients to control their symptoms, and the potential limitations of the techniques available to evaluate therapeutic outcomes. This review identifies some of the pitfalls encountered in recent clinical trials in dry eye disease. The peculiarities of dry eye disease with respect to symptoms, signs, and pathophysiological changes are discussed. Potential problems that apply to all clinical trials, including patient selection, randomization in small populations, and assessment of the placebo effect, are presented with respect to dry eye clinical trials. Considerations regarding study design address inclusion/exclusion criteria and selection of outcome measures. Special attention is given to methods of symptom analysis, techniques of staining of the ocular surface, and grading systems for surface staining. Alternative methods to the standard clinical trial are mentioned to place them in perspective for overall evaluation of dry eye disease therapy. Finally, caveats are provided to encourage investigators to vigorously conduct future clinical trials in dry eye therapy.

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  • Cited by (0)

    1

    Single copy reprint requests to: Gary N. Foulks, MD, FACS, Professor of Ophthalmology, Director of Clinical Research, Department of Ophthalmology, Eye and Ear Institute, University of Pittsburgh School of Medicine

    2

    Dr. Foulks is a consultant to Allergan, Inc., Inspire, Inc., and Daiichi, Inc., and his institution receives research grant support from these companies. He is a shareholder in Inspire, Inc.

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