Objective: Contact lens wear is often associated with signs and symptoms of ocular dryness. These drying effects can be exacerbated by certain environmental factors such as low humidity, wind, and visual tasks. The objective of the study was to compare the ability of senofilcon A contact lenses to subjects' habitual contact lenses to provide relief from the subjects' perceived ocular discomfort during contact lens wear in adverse environmental conditions.
Research design and methods: Eleven subjects completed a single-center, double-masked, randomized, cross-over, pilot clinical trial. At the qualification visit, and subsequently wearing senofilcon A study lenses (ACUVUE OASYS Brand Contact Lenses with HYDRACLEAR Plus) and control (habitual) lenses at the following visits, subjects underwent a total of three 75-min Controlled Adverse Environment (CAE) exposures. The primary efficacy variable measured during the 2-week, 3-visit trial was subject-reported ocular discomfort during CAE exposure measured on a five-point scale from 0 (none) to 4 (worst). The endpoint of ocular discomfort was evaluated using a two-sided t-test based on a longitudinal linear mixed model. Lenses were also evaluated for safety, and all adverse events were monitored.
Results: Subjects reported a significantly better mean comfort score when wearing senofilcon A contact lenses (1.62 +/- 0.71 units) compared to the mean comfort score reported when wearing habitual lenses (2.21 +/- 0.80 units) over the course of an entire CAE exposure (p = 0.0068). During exposure, senofilcon A lenses also yielded significantly better mean overall discomfort scores versus no lenses (2.73 +/- 0.79 points, p < 0.0001).
Conclusions: Senofilcon A contact lenses provided greater relief of subjective ocular discomfort associated with lens wear in adverse environmental conditions than that afforded by both the habitual lenses of contact lens wearers as well as with no contact lens wear. These results should be verified in a larger, appropriately-powered study.