Comparison of Ocular Lubricants in People With Symptoms of Dry Eye (SPHINX)

August 28, 2026 updated by: University of Waterloo

Symptomology Changes With Systane PRO PF Versus Thealoz Duo

Ocular dryness and discomfort are symptoms commonly associated with dry eye. Lubricating eye drops, also called artificial tears, are often used to moisten the eye and provide relief from these symptoms. There are currently several types of lubricating eye drops available, differing in their ingredients, consistency, and recommended frequency of application. The aim of this study is to compare the effectiveness of two lubricating eye drops that differ in their ingredients and recommended frequency of application. The goal is to see whether they perform the same or if one of them provides better relief for people with dry eye symptoms. One of the eye drops is commercially available in Canada, the other one is not commercially available in Canada and therefore considered an investigational eye drop. This eye drop is available in the United States of America. In this study, participants will use one drop twice per day and the other drop four times per day. Each product will be used for 4 weeks and all participants will use both products (one after the other). There will be a 2-week period of no drops between the two study products. Before starting each drop and after 4 weeks of drop use, we will assess the eyes of the participants and ask them how their eyes feel. Participants will also be asked to answer a series of questions regarding the drops. Participants will encounter procedures that they normally experience in an eye care setting. The results will help the funding company to better understand the performance of the products used in this study. It may also help eyecare practitioners in managing their patients with dry eye symptoms. The hypothesis is that the drop used twice a day will be non-inferior to the drop used 4 times per day for the change in dry eye symptoms (assessed with the Ocular Surface Disease Index questionnaire) after 4 weeks of use.

Study Overview

Status

Status

Indicates the current recruitment status or the expanded access status.
Completed

Conditions

Conditions

The disease, disorder, syndrome, illness, or injury that is being studied. On ClinicalTrials.gov, conditions may also include other health-related issues, such as lifespan, quality of life, and health risks.

Intervention / Treatment

Intervention / Treatment

A process or action that is the focus of a clinical study. Interventions include drugs, medical devices, procedures, vaccines, and other products that are either investigational or already available. Interventions can also include noninvasive approaches, such as education or modifying diet and exercise.

Study Type

Study Type

Describes the nature of a clinical study. Study types include interventional studies (also called clinical trials), observational studies (including patient registries), and expanded access.
Interventional

Enrollment (Actual)

Enrollment

The number of participants in a clinical study. The "anticipated" enrollment is the target number of participants that the researchers need for the study.
36

Phase

Phase

The stage of a clinical trial studying a drug or biological product, based on definitions developed by the U.S. Food and Drug Administration (FDA). The phase is based on the study's objective, the number of participants, and other characteristics. There are five phases: Early Phase 1 (formerly listed as Phase 0), Phase 1, Phase 2, Phase 3, and Phase 4. Not Applicable is used to describe trials without FDA-defined phases, including trials of devices or behavioral interventions.
  • Phase 4

Contacts and Locations

This section provides the contact details for those conducting the study, and information on where this study is being conducted.

Study Contact

Study Contact

The name and contact information for the person who can answer enrollment questions for a clinical study. Each location where the study is being conducted may also have a specific contact, who may be better able to answer those questions.

Study Contact Backup

Study Locations

  • Canada
    • Ontario
      • Waterloo, Ontario, Canada, N2L 3G1
        • Centre for Ocular Research & Education (CORE)

Participation Criteria

Researchers look for people who fit a certain description, called eligibility criteria. Some examples of these criteria are a person's general health condition or prior treatments.

Eligibility Criteria

Eligibility Criteria

The key requirements that people who want to participate in a clinical study must meet or the characteristics they must have. Eligibility criteria consist of both inclusion criteria (which are required for a person to participate in the study) and exclusion criteria (which prevent a person from participating). Types of eligibility criteria include whether a study accepts healthy volunteers, has age or age group requirements, or is limited by sex.

Ages Eligible for Study

  • Adult
  • Older Adult

Accepts Healthy Volunteers

No

Description

Inclusion Criteria:

  1. Are at least 18 years of age and have full legal capacity to volunteer;
  2. Have understood and signed an institutional review board (IRB)/ independent ethics committee (IEC) approved informed consent form;
  3. Are willing and able to attend all study visits as required per protocol;
  4. Are willing to discontinue use of all habitual artificial tear supplements and use only the study drops as directed for the entire study duration;

  5. Have dry eye symptomatology as per Tear Film & Ocular Surface Society Dry Eye WorkShop (TFOS DEWS) II definition:

    • Have an Ocular Surface Disease Index (OSDI) score ≥13;
  6. Have an absence of active* anterior segment disease;
  7. Have not worn contact lenses for the previous 14 days before screening, and are willing to not wear contact lenses for the duration of the study;
  8. Are correctable to a visual acuity of +0.20 LogMAR or better (in at least one eye) with refraction results.

Exclusion Criteria:

  1. Have taken part in an interventional clinical study within the previous 14 days before screening;
  2. Are participating in any concurrent ocular or interventional clinical trial;
  3. Have any active* ocular inflammation, infection, or are using ocular topical treatment (other than dry eye drops);
  4. Started any systemic medication known to cause dry eye (e.g., anti-histamine, antidepressants, benzodiazepines, etc.) within 30 days before screening. Stable dosing for >30 days before screening is allowed, but changes (including commencing new) of dosing of such medication within the study period would lead to early exit from the study;
  5. Had any ocular injury or surgery within the 1 year prior to screening, nor have ocular surgery planned/ anticipated;
  6. Have biomicroscopy signs of grade 3 or more (Efron scale);
  7. Have known sensitivity to the diagnostic pharmaceuticals or to any ingredients in the study products;
  8. Are pregnant, lactating or planning a pregnancy at the time of enrolment;
  9. Are a member of the Centre for Ocular Research & Education directly involved in this study (on the delegation log);
  10. Are an employee of Alcon.

Study Plan

This section provides details of the study plan, including how the study is designed and what the study is measuring.

How is the study designed?

Design Details

  • Primary Purpose: Treatment
  • Allocation: Randomized
  • Interventional Model: Crossover Assignment
  • Masking: Double

Arms and Interventions

Participant Group / Arm

Participant Group / Arm

A group or subgroup of participants in a clinical trial that receives a specific intervention/treatment, or no intervention, according to the trial's protocol.
Intervention / Treatment

Intervention / Treatment

A process or action that is the focus of a clinical study. Interventions include drugs, medical devices, procedures, vaccines, and other products that are either investigational or already available. Interventions can also include noninvasive approaches, such as education or modifying diet and exercise.
Experimental: Systane Pro PF/ Thealoz Duo
Use of Systane Pro PF for 4 weeks, followed by use of Thealoz Duo for 4 weeks
Drug: Propylene glycol 0.6%
1 drop per eye multiple times per day for 4 weeks
Device: 3% trehalose and 0.15% sodium hyaluronate
1 drop per eye multiple times per day for 4 weeks
Experimental: Thealoz Duo / Systane Pro PF
Use of Thealoz Duo for 4 weeks, followed by use of Systane Pro PF for 4 weeks
Drug: Propylene glycol 0.6%
1 drop per eye multiple times per day for 4 weeks
Device: 3% trehalose and 0.15% sodium hyaluronate
1 drop per eye multiple times per day for 4 weeks

What is the study measuring?

Primary Outcome Measures

Primary Outcome Measures

In a clinical study's protocol, the planned outcome measure that is the most important for evaluating the effect of an intervention/treatment. Most clinical studies have one primary outcome measure, but some have more than one.
Outcome Measure
Measure Description
Time Frame
Difference Ocular Surface Disease Index (OSDI) Score between Baseline and 4 Weeks
Time Frame: From baseline (dispense) to 4 weeks of ocular lubricant use
Within-subject difference in OSDI scores between baseline and after 4 weeks of use with each drop
From baseline (dispense) to 4 weeks of ocular lubricant use

Collaborators and Investigators

This is where you will find people and organizations involved with this study.

Sponsor

Sponsor

The organization or person who initiates the study and who has authority and control over the study.
University of Waterloo

Collaborators

Collaborators

An organization other than the sponsor that provides support for a clinical study. This support may include activities related to funding, design, implementation, data analysis, or reporting.
Alcon Research

Investigators

Investigators

A researcher involved in a clinical study. Related terms include site principal investigator, site sub-investigator, study chair, study director, and study principal investigator.
  • Principal Investigator: Jill Woods, MSc, MCOptom, Centre for Ocular Research & Education

Study record dates

These dates track the progress of study record and summary results submissions to ClinicalTrials.gov. Study records and reported results are reviewed by the National Library of Medicine (NLM) to make sure they meet specific quality control standards before being posted on the public website.

Study Major Dates

Study Start (Actual)

Study Start

The actual date on which the first participant was enrolled in a clinical study. The "anticipated" study start date is the date that the researchers think will be the study start date.
February 23, 2026

Primary Completion (Actual)

Primary Completion

The date on which the last participant in a clinical study was examined or received an intervention to collect final data for the primary outcome measure. Whether the clinical study ended according to the protocol or was terminated does not affect this date. For clinical studies with more than one primary outcome measure with different completion dates, this term refers to the date on which data collection is completed for all the primary outcome measures. The "anticipated" primary completion date is the date that the researchers think will be the primary completion date for the study.
August 10, 2026

Study Completion (Actual)

Study Completion

The date on which the last participant in a clinical study was examined or received an intervention/treatment to collect final data for the primary outcome measures, secondary outcome measures, and adverse events (that is, the last participant's last visit). The "anticipated" study completion date is the date that the researchers think will be the study completion date.
August 10, 2026

Study Registration Dates

First Submitted

First Submitted

The date on which the study sponsor or investigator first submitted a study record to ClinicalTrials.gov. There is typically a delay of a few days between the first submitted date and the record's availability on ClinicalTrials.gov (the first posted date).
February 27, 2026

First Submitted That Met QC Criteria

First Submitted That Met QC Criteria

The date on which the study sponsor or investigator first submits a study record that is consistent with National Library of Medicine (NLM) quality control (QC) review criteria. The sponsor or investigator may need to revise and submit a study record one or more times before NLM's QC review criteria are met. It is the responsibility of the sponsor or investigator to ensure that the study record is consistent with the NLM QC review criteria.
February 27, 2026

First Posted (Actual)

First Posted

The date on which the study record was first available on ClinicalTrials.gov after National Library of Medicine (NLM) quality control (QC) review has concluded. There is typically a delay of a few days between the date the study sponsor or investigator submitted the study record and the first posted date.
March 5, 2026

Study Record Updates

Last Update Posted (Actual)

Last Update Posted

The most recent date on which changes to a study record were made available on ClinicalTrials.gov. There may be a delay between when the changes were submitted to ClinicalTrials.gov by the study's sponsor or investigator (the last update submitted date) and the last update posted date.
September 1, 2026

Last Update Submitted That Met QC Criteria

Last Update Submitted That Met QC Criteria

The most recent date on which the study sponsor or investigator submitted changes to a study record that are consistent with National Library of Medicine (NLM) quality control (QC) review criteria. It is the responsibility of the sponsor or investigator to ensure that the study record is consistent with the NLM QC review criteria.
August 28, 2026

Last Verified

Last Verified

The most recent date on which the study sponsor or investigator confirmed the information about a clinical study on ClinicalTrials.gov as accurate and current. If a study with a recruitment status of recruiting; not yet recruiting; or active, not recruiting has not been confirmed within the past 2 years, the study's recruitment status is shown as unknown.
February 1, 2026

More Information

Terms related to this study

Other Study ID Numbers

Other Study ID Numbers

Identifiers or ID numbers other than the NCT number that are assigned to a clinical study by the study's sponsor, funders, or others. These numbers may include unique identifiers from other trial registries and National Institutes of Health grant numbers.
  • 47903
  • 98631981 (Other Grant/Funding Number: Alcon (IIT))

Plan for Individual participant data (IPD)

Plan to Share Individual Participant Data (IPD)?

NO

Drug and device information, study documents

Studies a U.S. FDA-regulated drug product

Yes

Studies a U.S. FDA-regulated device product

No

product manufactured in and exported from the U.S.

Yes

This information was retrieved directly from the website clinicaltrials.gov without any changes. If you have any requests to change, remove or update your study details, please contact register@clinicaltrials.gov. As soon as a change is implemented on clinicaltrials.gov, this will be updated automatically on our website as well.

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