A Comparison of Two Contact Lenses

Study Overview
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Brief Summary
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This study seeks to evaluate the clinical and subjective performance of two established soft contact lenses.

Conditions
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Refractive Error, Myopia

Intervention / Treatment
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* Device: senofilcon A
* Device: balafilcon A


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: They are of legal age (18 years) and capacity to volunteer. They understand their rights as a research subject and are willing to sign a Statement of Informed Consent. They are willing and able to follow the protocol. They would be expected to attain at least 6/9 (20/30) in each eye with the study lenses. They are able to wear contact lenses with a back vertex power of -1.00 to -6.00DS. They have a maximum of 1.00D of refractive astigmatism (i.e. ≤ 1.00 DC). They have successfully worn contact lenses within six months of starting the study. Exclusion Criteria: They have an ocular disorder which would normally contra-indicate contact lens wear. They have a systemic disorder which would normally contra-indicate contact lens wear. They are using any topical medication such as eye drops or ointment. They are aphakic. They have had corneal refractive surgery. They have any corneal distortion resulting from previous hard or rigid lens wear or has keratoconus. They are pregnant or lactating. They have grade 2 or greater of any of the following ocular surface signs: corneal oedema, corneal vascularisation, corneal staining, tarsal conjunctival changes or any other abnormality which would normally contraindicate contact lens wear. They have any infectious disease (e.g. hepatitis) or any immunosuppressive disease (e.g. HIV). They have diabetes. They have taken part in any other clinical trial or research, within two weeks prior to starting this study.

Ages Eligible for Study
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Minimum Age: 18 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Treatment
Allocation: Randomized
Intervention Model: Crossover Assignment
Masking: Single


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Active Comparator: senofilcon A/balafilcon A<br>senofilcon A silicone hydrogel contact lens worn during first 4-week period, balafilcon A silicone hydrogel contact lens worn during the second 4-week period. Senofilcon A lenses worn daily on a 2-week replacement schedule; balafilcon A lenses worn daily on a 4-week replacement schedule. Lens replacement conducted in-office in a masked process. | Device: senofilcon A<br>* silicone hydrogel contact lens<br>Device: balafilcon A<br>* silicone hydrogel contact lens<br>|
| Active Comparator: balafilcon A/senofilcon A<br>balafilcon A silicone hydrogel contact lens worn worn during first 4-week period, senofilcon A silicone hydrogel contact lens worn during the second 4-week period. Senofilcon A lenses worn daily on a 2-week replacement schedule; balafilcon A lenses worn daily on a 4-week replacement schedule. Lens replacement conducted in-office in a masked process. | Device: senofilcon A<br>* silicone hydrogel contact lens<br>Device: balafilcon A<br>* silicone hydrogel contact lens<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Patient-reported Comfort at at the Manufacturer's Recommended Lens Replacement Timeframe of 2-weeks (Senofilcon A) or 4-weeks (Balafilcon A). | Subjective rating of overall comfort using a 0 through 5 scale. 0=n/a, 1=poor, 2=fair, 3=good, 4=very good, 5=excellent. Scores from 2-week and 4-week visits were combined for final values. | after 4 weeks of lens wear |