The Clinical Comparison of Narafilcon A and Stenfilcon A Contact Lenses

The Clinical Comparison of Narafilcon A and Stenfilcon A Contact Lenses

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.

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.

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.