Evaluating the Efficacy of a New Lubricant Eye Drop
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Evaluating the Efficacy of a New Lubricant Eye Drop
BY JOHN L. SCHACHET, OD
Dry eye is a complex, multifactorial disease of the tear film and ocular surface that results in symptoms of discomfort, visual disturbance, and tear film instability and can lead to ocular surface damage. Discomfort symptoms often associated with dry eye include burning, stinging, grittiness, foreign body sensation, tearing, ocular fatigue, and dryness. Various daily activities and environmental factors, such as extended visual tasking (television viewing, video gaming, and computer use), dry air, pollutants, and certain medications may precipitate and/or exacerbate dry eye.
The first step in managing dry eye is to identify the underlying etiology and to attempt to eliminate the causative agent(s). Afterward, regardless of the etiology, the first-line therapy is typically external augmentation of the tear film by the administration of topical artificial tear substitutes.
A New Lubricant Drop
Systane Ultra (Alcon) is a new hydroxypropyl (HP)-guar-based lubricant eye drop product containing polyethylene glycol 400 (0.4%) and propylene glycol as active ingredients. A key contributor to the efficacy of this new product is the gelling agent HP-guar. This formulation also contains essential ions, sodium, borate, and sorbitol and is preserved with Polyquad. This therapeutic drop is specifically formulated to allow an interaction among the HP-guar, borate, and sorbitol to provide a loosely cross-linked matrix in the bottle. Upon instillation, the tear film dilutes the highly-soluble sorbitol to allow HP-guar and borate, along with the naturally present divalent ions in the tear film, to form a highly structured network of protection on the corneal epithelium. This network is achieved by introducing a viscoelastic property that provides a bandage-like protection to the ocular surface without interfering with the quality of vision (Ketelson et al, 2008).
Surveying Dry Eye Patients
Eyecare professionals in multiple geographical locations in the United States selected 14,000 patients who exhibited the classic symptoms of dry eye to participate in a post-marketing survey. The objectives of the survey were to evaluate the clinical effectiveness of, and patient satisfaction with, the new HP-guar-based lubricant eye drops in relieving symptoms associated with dry eye. All subjects received Systane Ultra in its commercial packaging. Practitioners instructed subjects to apply the product as needed for two weeks and to answer questionnaires evaluating drop effectiveness and quality of life (QOL) and mail them to a central data management center (DMC) for analysis at the end of the two-week treatment period.
Data were analyzed using descriptive statistical measures. This program maintained compliance with the Health Insurance Portability and Accountability Act (HIPAA) because no patient-specific data was included in the analysis. This project was exempt from Institutional Review Board approval.
Two weeks after using the new HP-guar-based eye drop, 1,053 subjects completed and returned the written questionnaires to the DMC. Using a five-point scale (strongly agree, agree, neutral, disagree, and strongly disagree), subjects evaluated Systane Ultra. Eighty-nine percent of the subjects reported that the product was soothing to their eyes, 77 percent reported that it was comfortable, 72 percent reported that it was long-lasting, 81 percent said that it provided a coat of moisture on the eye, and 81 percent reported that it relieved the discomfort associated with dryness. When asked to rate the side effects that usually are associated with artificial tears on the same five-point scale, 87 percent reported that the product did not burn upon instillation, 63 percent said that it did not lead to foggy or blurred vision, and 86 percent reported that it did not feel oily. Moreover, 82 percent of subjects reported that they did not experience crusting in the morning.
With respect to the QOL outcomes, 84 percent of subjects preferred the new product to the product they had used previously. When specifically asked about situations related to ocular and/or visual quality, 88 percent found Systane Ultra to be more comfortable than the product they previously used, 75 percent could read longer and more comfortably with this product than with their previous product, 76 percent reported that they could watch television and use a computer longer, and 62 percent could drive at night more comfortably.
The results of this survey demonstrate that the new HP-guar-based lubricant eye drop is effective in relieving symptoms associated with dry eye. Additionally, the drop reportedly improves visual functions and QOL. While additional clinical evaluation is warranted to further understand the efficacy of this artificial tear product, these data strongly suggest that Systane Ultra should be considered a valuable addition to the available therapies for dry eye disease. CLS
Alcon Laboratories, Inc. sponsored this study. The author is a consultant of Alcon Laboratories, Inc. and has no financial interest in Systane Ultra lubricant eye drops.
The author thanks Heba Costandy, MD, MS, for editorial assistance.
For references, please visit www.clspectrum.com/references.asp and click on document #164.
Dr. Schachet is in private practice in Englewood, Colo. He is a senior partner in a five-doctor practice, specializing in contact lenses, dry eye, and ocular allergy. He has received research funds from Alcon and Paragon and has served on advisory panels for Alcon and CooperVision.
Contact Lens Spectrum, Issue: July 2009