MedPath

The Clinical Comparison of Narafilcon A and Stenfilcon A Contact Lenses

Not Applicable
Completed
Conditions
Myopia
Interventions
Device: stenfilcon A
Device: narafilcon A
Registration Number
NCT02920970
Lead Sponsor
Coopervision, Inc.
Brief Summary

This study aims to compare the clinical performance and subjective acceptance of the narafilcon A lens with the stenfilcon A lens when used on a daily wear, daily disposable basis.

Detailed Description

This will be a randomized, subject-masked, crossover, bilateral study, controlled by cross comparison. Seventy subjects will use each lens type for a week in a random sequence. Follow-up visits for each lens will be performed after one week of wear. Lenses will be worn on a daily wear, daily disposable wear schedule.

Recruitment & Eligibility

Status
COMPLETED
Sex
All
Target Recruitment
72
Inclusion Criteria
  • Subjects will only be eligible for the study if:

    1. They are of legal age (18) and capacity to volunteer.
    2. They understand their rights as a research subject and are willing and able to sign a Statement of Informed Consent.
    3. They are willing and able to follow the protocol.
    4. They agree not to participate in other clinical research for the duration of this study.
    5. They have a contact lens spherical prescription between -1.00 to - 6.00D (Diopters) (inclusive)
    6. They have a spectacle cylindrical correction of -0.75D or less in each eye.
    7. They can be satisfactorily fitted with the study lens types.
    8. At dispensing, they can attain at least 0.10 logMAR distance high contrast visual acuity in each eye with the study lenses within the available power range.
    9. They currently use soft contact lenses or have done so in the previous six months.
    10. They are willing to comply with the wear schedule (at least six days per week and for at least eight hours per day).
    11. They own a wearable pair of spectacles.
Exclusion Criteria
  • Subjects will not be eligible to take part in the study if:

    1. They have an ocular disorder which would normally contra-indicate contact lens wear.
    2. They have a systemic disorder which would normally contra-indicate contact lens wear.
    3. They are using any topical medication such as eye drops or ointment.
    4. They have had cataract surgery.
    5. They have had corneal refractive surgery.
    6. They have any corneal distortion resulting from previous hard or rigid lens wear or have keratoconus.
    7. They are pregnant or breast-feeding.
    8. They have any ocular abnormality which would, in the opinion of the investigator, normally contraindicate contact lens wear.
    9. They have any infectious disease which would, in the opinion of the investigator, contraindicate contact lens wear or pose a risk to study personnel; or they have any immunosuppressive disease (e.g. HIV), or a history of anaphylaxis or severe allergic reaction.
    10. They have taken part in any other contact lens or care solution clinical trial or research, within two weeks prior to starting this study.
    11. They currently wear either the stenfilcon A lens or narafilcon A lens.

Study & Design

Study Type
INTERVENTIONAL
Study Design
CROSSOVER
Arm && Interventions
GroupInterventionDescription
stenfilcon Astenfilcon AParticipants are randomized to wear stenfilcon A lens pair for one week during the cross over study.
narafilcon Anarafilcon AParticipants are randomized to wear narafilcon A lens pair for one week during the cross over study.
Primary Outcome Measures
NameTimeMethod
Ocular Physiology1 week

Ocular physiology assessment of narafilcon A and stenfilcon A lenses by biomicroscopy (Scale 0-4, 0.25 steps, 0=normal, 4=severe).

Visual Acuity1 week

Visual acuity for narafilcon A and stenfilcon A are assessed by LogMAR. High contrast is measured with black letters on a white background. Low contrast is measured with gray letters on a white background.

Comfort Level of Stenfilcon A and Narafilcon A Lenses1 week

Subjective responses for overall comfort will be evaluated for each pair using questionnaire (Scale 0-100, 0=causes pain, cannot be tolerated, 100=excellent, cannot be felt).

Dryness of Stenfilcon A and Narafilcon A Lenses1 week

Subjective responses for dryness will be evaluated for each pair using questionnaire (Scale 0-100, 0=extremely poor, high levels of dryness, 100=excellent, no dryness).

Vision of Stenfilcon A and Narafilcon A Lenses1 week

Subjective responses for vision will be evaluated for each pair using questionnaire (Scale 0-100, 0=unacceptable, lens cannot be worn, 100=excellent).

Lens Surface - Deposition on Stenfilcon A and Narafilcon A Lenses1 week

Lens surface for narafilcon A and stenfilcon A is assessed. (Grades 0-4, 0=normal, 1=trace, 2=mild, 3=moderate, 4=severe)

Lens Surface - Wettability of Stenfilcon A and Narafilcon A Lenses1 week

Lens wettability for narafilcon A and stenfilcon A is assessed. (Grades 0-4, 0=normal, 1=trace, 2=mild, 3=moderate, 4=severe)

Lens Fit - Horizontal Centration of Stenfilcon A and Narafilcon A Lenses1 week

Horizontal centration assessed for narafilcon A and stenfilcon A lenses categorized as extremely nasal, slightly nasal, optimum, slightly temporal, extremely nasal.

Lens Fit - Vertical Centration of Stenfilcon A and Narafilcon A Lenses1 week

Vertical centration assessed for narafilcon A and stenfilcon A lenses and graded as extremely nasal, slightly nasal, optimum, slightly temporal, extremely temporal.

Lens Fit - Corneal Coverage of Stenfilcon A and Narafilcon A Lenses1 week

Corneal coverage will be assessed for narafilcon A and stenfilcon A and categorized as extremely inadequate, slightly inadequate, optimum, slightly excessive, extremely excessive.

Lens Movement1 week

Lens movement assessed for narafilcon A and senofilcon A lenses and categorized as extremely inadequate, slightly inadequate, optimum, slightly excessive, extremely excessive.

Secondary Outcome Measures
NameTimeMethod

Trial Locations

Locations (1)

Eurolens Research - The University of Manchester

🇬🇧

Manchester, United Kingdom

© Copyright 2025. All Rights Reserved by MedPath