Skip to main content
OpenTrials
Completed

NCT Number: NCT07722650

Twice-Daily Systane Complete Versus Four-Times-Daily Thealoz Duo for Dry Eye Disease

The goal of this clinical trial is to learn whether a twice-daily dosing schedule of Systane Complete eye drops works as well as a four-times-daily dosing schedule of Thealoz Duo eye drops to treat dry eye disease in adults. The main questions it aims to answer are:

* Does twice-daily Systane Complete provide similar improvement in dry eye symptoms, measured by the Ocular Surface Disease Index (OSDI), compared with four-times-daily Thealoz Duo after 30 days of treatment? * How do the treatments affect tear film stability, tear production, and damage to the surface of the eye?

Researchers will compare Systane Complete (used twice a day) to Thealoz Duo (used four times a day) to see if the simpler dosing schedule maintains similar benefits for symptoms and eye surface health.

Participants will be adults with mild to moderate dry eye disease who are seen in an outpatient eye clinic. They will be randomly assigned to one of the two treatment groups. All participants will use their assigned eye drops in both eyes for 30 days and will attend clinic visits at the start of the study and after 30 days. At each visit, participants will complete the OSDI questionnaire and undergo standard eye tests, including tear break-up time, Schirmer test, and grading of surface staining on the eye.

Completed

Looking for future studies?

Notify Me

Key information

Conditions

Dry Eye Syndrome (DES) Dry Eye Syndromes Eye Diseases Lacrimal Apparatus Diseases Ocular Surface Disease

Age range

18 year and older

Sex eligibility

All sexes

Study type

Interventional

Phase

Not applicable

Primary location

Hospital Puerta de Hierro

Zapopan, Jalisco, Mexico

Who can participate

Healthy volunteers accepted: No

Only the study team can determine whether someone qualifies for participation.

Inclusion criteria

  • Adults (≥18 years of age) with mild to moderate dry eye disease (DED).
  • Ocular Surface Disease Index (OSDI) score between 13 and 32 at baseline.
  • At least one abnormal objective test of ocular surface dysfunction, defined as one or more of the following:
  • Schirmer test result < 10 mm in 5 minutes (without anesthesia), or
  • Tear break-up time (TBUT) < 10 seconds, or
  • Ocular surface staining graded between stages 1 and 3 according to the Oxford scale.
  • Best-corrected visual acuity of 20/200 or better in both eyes.
  • Able to provide written informed consent and comply with study procedures and scheduled visits.

Exclusion criteria

  • Pregnancy or breastfeeding.
  • Participation in another clinical trial or prior participation in the present study.
  • Best-corrected visual acuity worse than 20/200 in either eye.
  • Active ocular disease including conjunctivitis, blepharitis, keratitis, ocular trauma, ocular surface scarring, corneal ulcers, neurotrophic keratitis, bullous keratopathy, or neoplastic disease of the ocular surface.
  • Glaucoma or eyelid disorders that affect normal eyelid function.
  • Advanced dry eye disease requiring second-line TFOS DEWS II therapy.
  • Ocular surgery within the previous 3 months.
  • Contact lens use within 15 days prior to enrollment.
  • Known hypersensitivity to any component of the study medications.
  • Substance dependence within the previous 2 years.
  • Systemic conditions that could increase the risk of study participation or interfere with interpretation of study outcomes, as judged by the investigators.
  • Women of childbearing potential not using stable contraceptive methods for at least 30 days prior to enrollment and throughout the study duration.

Treatment and study plan

Systane COMPLETE

Drug

Systane Complete is a commercially available lipid-containing artificial tear formulation that combines mineral oils with nano-droplet lipid technology to support all three layers of the tear film (lipid, aqueous, and mucin). In this study, participants assigned to this intervention will instill one to two drops in each eye twice daily for 30 days, maintaining a minimum interval of eight hours between doses and avoiding additional topical ophthalmic medications during the study period unless clinically necessary and documented by investigators.

Other names: Lipid-containing artificial tears

Thealoz Duo

Drug

Thealoz Duo is a commercially available ophthalmic solution that combines hyaluronic acid with trehalose to protect the ocular surface and support epithelial recovery in dry eye disease. In this study, participants assigned to this intervention will instill one to two drops in each eye four times daily for 30 days, maintaining a minimum interval of four hours between doses and avoiding additional topical ophthalmic medications during the study period unless clinically necessary and documented by investigators.

Other names: Hyaluronic acid and trehalose ophthalmic solution

Primary outcomes

  1. Change in Ocular Surface Disease Index (OSDI) score from baseline to day 30

    Time frame: From baseline (day 0) to day 30 of treatment

    The Ocular Surface Disease Index (OSDI) is a validated 12-item questionnaire that measures the frequency of dry eye symptoms and their impact on visual function and daily activities. Scores range from 0 to 100, with higher scores indicating more severe symptoms. In this trial, participants complete the OSDI at baseline and after 30 days of treatment. The primary outcome is the adjusted mean OSDI score at day 30, analyzed using analysis of covariance (ANCOVA) with baseline OSDI as a covariate to compare twice-daily Systane Complete with four-times-daily Thealoz Duo within a non-inferiority framework.

Secondary outcomes

  1. Change in tear break-up time (TBUT) from baseline to day 30

    Time frame: Baseline and day 30 after start of treatment

    Tear break-up time (TBUT) is measured using fluorescein dye as the interval in seconds between a complete blink and the first appearance of a discontinuity in the tear film. TBUT is assessed in both eyes at baseline and at day 30 under controlled environmental conditions; values from the right and left eyes are averaged to obtain a single patient-level value. The secondary outcome is the change in mean TBUT (seconds) from baseline to day 30 and the between-group comparison of TBUT at day 30.

  2. Change in Schirmer test value from baseline to day 30

    Time frame: Baseline and day 30 after start of treatment

    Schirmer test without anesthesia is used to assess tear production by placing filter paper strips in the lower eyelid for 5 minutes and measuring the length of wetting in millimeters. Schirmer test is performed in both eyes at baseline and at day 30; measurements from right and left eyes are averaged to generate a single patient-level value. The secondary outcome is the change in mean Schirmer test value (millimeters) from baseline to day 30 and the between-group comparison of Schirmer values at day 30.

  3. Change in Oxford corneal and conjunctival staining score from baseline to day 30

    Time frame: Baseline and day 30 after start of treatment

    Corneal and conjunctival epithelial staining is evaluated using fluorescein and graded according to the Oxford grading scale for ocular surface staining. The Oxford scale ranges from grade 0 (no staining) to grade 5 (severe staining), with higher grades indicating more extensive epithelial damage. Staining is assessed in both eyes at baseline and at day 30; scores from the right and left eyes are averaged to obtain a single patient-level value. The secondary outcome includes the change in mean Oxford staining score from baseline to day 30 and the proportion of participants achieving complete resolution of corneal staining (Oxford grade 0) at day 30 in each treatment group.

  4. Treatment adherence over 30 days of follow-up

    Time frame: Day 15 and day 30 of treatment

    Treatment adherence is evaluated using patient-completed daily treatment diaries that record each administration of the assigned study medication. Adherence (%) is calculated using the formula AD = (RA × 100) / IA, where RA is the number of recorded administrations and IA is the total number of indicated applications according to the prescribed dosing regimen. Adherence is assessed at day 15 and day 30. Participants with adherence values below 90% are considered to have protocol deviations and are excluded from the per-protocol analysis.

Sponsors and collaborators

Lead sponsor

Instituto Internacional de Medicina y Terapia (IIMET)

Other

Collaborators

  • Centro de Retina Médica y Quirúrgica S.C.
  • Hospital Puerta de Hierro, Zapopan

Registry information

Official study title

Twice-Daily Systane Complete Versus Four-Times-Daily Thealoz Duo for Dry Eye Disease: A Randomized Controlled Non-Inferiority Trial

Important dates

Study start
2025
Primary completion
2025
Study completion
2025
First posted
Jul 23, 2026
Registry last updated
Jul 24, 2026

OpenTrials presents study information sourced from ClinicalTrials.gov. The official registry record should be consulted for the latest information.

View the official ClinicalTrials.gov record (opens in a new tab)

This listing is for discovery and informational purposes only. It is not medical advice, does not guarantee that a study is recruiting, and does not determine eligibility. Contact the study team and a qualified healthcare professional when considering participation.

Related clinical trials

Published trials that share one or more normalized conditions with this study.