Effect of Contact Lens With Alginic Acid in Dry Eye Patients
Condition: Dry Eyes
MeSH terms: Dry Eye Syndromes; Keratoconjunctivitis Sicca
Study type: Interventional

Summary: 
      Contact lens induced dry eyes leads to lens intolerance and discontinuation. Incidence of dry
      eye in contact lens wearer is significantly higher in Asian population compared to other
      ethnic group considering Asian has lower tear break up time. Disruptions of tear integrity in
      contact lens wearer will further exacerbate the condition. Factors for successful contact
      lens fitting derive from the biocompatibility of lens material, lens design and stability of
      tear film in front of the contact lens. This study aim to investigate the efficacy of a novel
      daily disposable contact lens with zwitterionic material that contains alginic acid which act
      as a moisturizing agent. The improved lens material may likely improve the comfort and treat
      symptomatic wearers.
    

Detailed description: 
      This study will be conducted in compliance with the protocol, SGCP and the applicable
      regulatory requirements.

      Dry eye is a condition that affects 5-35% of the population.1 Common symptoms of this
      condition include eye irritation, heaviness of the eyelids, visual disturbances, tearing and
      light sensitivity.2 This significantly impacts the quality of life and vision of dry eye
      patients. In addition, there is a significant socio-economic burden. In 2009, 54,051 patients
      sought treatment for dry eye in the Singapore National Eye Centre (SNEC). In total, the costs
      for dry eye medication amounted to $181,354.17.15 Additionally, dry eye affects work
      productivity that further adds on to the socio-economic burden.16

      Contact lens-induced dry eye (CLIDE) mimic the symptoms found in dry eye patients. It was
      reported that contact lens wearer are 12 times more likely to report symptoms than emmetropes
      and 5 times more likely to report symptoms than spectacle wearers. Lipid layer and tear film
      break up time decrease during contact lens wear have been reported, leading to excessive
      evaporation, reduced tear volume and an increase in osmolality. Asian contact lens wearer
      experienced more severe dry eye symptoms compared to non wearer (Lungrin et al, ARVO 2008).
      Reports shown that Asian have shorter averaged tear break up time (TBUT) and lower tear
      volume. Symptom usually increases significantly over the course of the day (Begley and
      coworkers (2000)).

      Contact lens material and tear film stability has remained important in association with
      patient dryness symptoms. Lens hydration has been linked to the comfort of the wearer and
      perturbations of tear mechanism in contact lens wearer decrease the stability of tear film
      and thus decrease the comfort level. Evaporation of tear film has found to increase during
      lens wear. To date, silicone hydrogel lenses with surface technology that can mimic the
      ocular surface has found to be encouraging among wearers.

      A novel type of disposable contact lens has been developed in Japan (SEED 1dayPure moisture
      and 2 week pure). It corporate factors such as high water content, zwitterionic material
      containing alginic acid that acts as a moisturizing agent, high biocompatibility which has
      both positive and negative ions that prevents contamination, UV protection and shape
      stability which is suitable for patients suffering from contact lens induced dry eye.

      Contact lens induced dry eyes remain one of the major factor for contact lens drop out.
      Advanced lens material and replacement schedule may contribute largely in the acceptance of
      contact lens population. With the introduction on a novel disposable contact lens material,
      it may significantly improve the dry eye and comfort in symptomatic wearers. Practitioners
      may achieve a more successful fitting outcome.

      Recent technological advances, as well as the infrastructure of the Singapore Eye Research
      Institute (proximity to Singapore National Eye Center and pre-existing facility and
      infrastructure for clinical trials) have facilitated studies of products that are avaliable
      elsewhere and may benefit the Singaporean population.

      Contact lens induced dry eye leads to reduce wearing time and ultimately ceasing lens wear.
      Tear stability was reduced in symptomatic contact lens wearer and evaporation has shown to
      increase during lens wear.

      A novel type of contact lens with the ability to retain the moisture in the eye would be
      desirable in the management of contact lens induced dry eye (CLIDE), increase comfort and
      reduce contact lens dropouts.

      Methods Participants and target sample size Thirty symptomatic habitual contact lens wearer
      will be recruited for this study from the dry eye clinic in SNEC. Recruited patients will be
      randomly assigned to one of the 2 treatment arms.

      Treatment arms:

      Control: Same lens without alginic acid (n=15) Zwitterionic with alginic acid; SEED 1 dayPure
      Moisture (n=15)

      Patients will be asked to lay off from their habitual contact lenses for 2 days prior to the
      baseline visit. Wearing schedules are daily wear with daily replacement. Patients are advise
      to wear the contact lens every day during the study period of 7 days with a minimum of 8
      hours per day. They will also be instructed not to sleep with the contact lens.

      Visit schedules There will be a total of 3 study visits, including of screening visit which
      will be performed at the regular dry eye clinic. If eligible, patients will be scheduled for
      baseline visit. Subsequent follow up visit will be on the 7th day and 8th day. A window
      period of +/- 2 days is permitted for this study.

      Duration of study:

      Seven days.

      Primary Outcome

      • Difference of Visual Analogue Scale (VAS) for the ocular discomfort between control and
      treatment group.

      A VAS will be applied to evaluate dry eye symptoms as described by Schaumberg et al.
      (Schaumberg, Gulati et al. 2007). The scores will be recorded separately for frequency and
      severity of dry eye symptoms. The patient will be asked to check a point on a 100-mm line
      that corresponds to the degree of the symptom. The location of the mark made by the patient
      for each question will be measured in mm from the left hand side of the 100 mm line and
      recorded in mm. For the follow up visits, which measured the distance between the mark made
      by the patient and the central anchor, a negative value will be recorded if left of the
      anchor and a positive value if right of the anchor.

      A global score will be calculated by multiplying the frequency score by the severity score
      and taking the square root of the result (to transform back to the original scale).

      Secondary Outcomes

        -  Tear lipid layer thickness measurements of LipiView

        -  Schirmers I reading

        -  Tear break up time (TBUT)

        -  Corneal flourescein staining

        -  Tear proteomic analysis

      Inclusion Criteria

        1. Age of 21 years old and above and has full legal capacity to volunteer

        2. Soft contact lens wearer

        3. Willing to wear study lenses for at least 8 hours/day for 7 days

        4. Reports dryness symptoms with contact lens wear on questionnaire.

        5. Schirmers I with no aneasthesia of less than 10mm

        6. Is willing and able to follow instructions and maintain the appointment schedule

        7. Vision correctable to 6/9 (Snellen) or better in each eye at distance with study lenses
           at baseline

        8. Has a contact lens prescription between +4.00 to -6.00D with astigmatism <=-1.00

      Exclusion Criteria

        1. Requires concurrent ocular medication

        2. Is participating in any concurrent clinical or research study

        3. Has used Restasis® in the last 3 months

        4. Wears punctal plugs fitted in the last 1 month

        5. Any systemic illness which would contraindicate lens wear

        6. Diabetic

        7. Has had an eye injury or surgery within the last 3 months

        8. Keratoconus or other corneal irregularity

        9. Has had ocular surgery done within the previous 3 months

       10. Active ocular surface conditions such as infection or pterygium that may affect tear
           film stability.

       11. Is pregnant, lactating or planning a pregnancy

       12. Any other specified reason as determined by clinical investigator.
    

Intervention name(s): Contact Lens with alginic acid; Contact Lens without alginic acid
Intervention type(s): Device; Device
Intervention description(s): Worn for 7 days, at least 8 hours a day; Worn for 7 days, at least 8 hours a day
Allocation: Randomized
Intervention model: Parallel Assignment
Masking: Single (Participant)
Keywords: contact lens; alginic; dry eyes