An interventional study of Placebo and BL531_low dose in Digital Eye Strain (DES), sponsored by Synbio Tech Inc.. Recruiting at 1 site in Taiwan. Open to participants aged 20 Years to 65 Years, including healthy volunteers. Per ClinicalTrials.gov, last updated 2026-11-02.
Sponsored by Synbio Tech Inc. · Not applicable, Interventional, and Prevention
With the widespread use of digital devices and prolonged screen exposure, digital eye strain (DES), also known as computer vision syndrome, has become a global public health concern. Emerging evidence suggests that the gut-eye axis may play an important role in ocular health, as gut microbiota imbalance is associated with systemic inflammation and oxidative stress. Specific probiotics may help alleviate eye discomfort through modulation of immune responses and enhancement of antioxidant defense mechanisms. This randomized, double-blind, placebo-controlled study aims to evaluate the efficacy of supplementation with specific probiotics, Bifidobacterium longum BL531 and Lactobacillus reuteri LR1349, in improving digital eye strain symptoms in adults.
67 studies on the registry are indexed under Asthenopia; 10 are open to participants now.
This study's planned enrollment of 150 is above the median of 56 across 56 interventional studies indexed under Asthenopia.
Browse Asthenopia studies →Synbio Tech Inc. is the lead sponsor of 2 studies on the registry; 1 is open to participants now.
Counted across the registry records on this site, refreshed daily.
Go through the criteria one by one — yes, no or not sure — and take the list to your doctor or the study team. Kept in this browser only.
Exclusion Criteria:
Underlined terms in the criteria open these too. Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
A condition in which the immune system attacks the body’s own tissues, such as rheumatoid arthritis, lupus, psoriasis, type 1 diabetes or inflammatory bowel disease.
Immunotherapy studies often leave out active autoimmune disease, and some name exceptions, such as thyroid disease on replacement hormone. Check the exceptions this study lists.
Anti-inflammatory medicines such as prednisone, prednisolone and dexamethasone — not the anabolic steroids used for muscle.
Studies differ in what they allow: check which steroid medicines, routes (tablets, injections, creams, inhalers, eye drops) and doses this study accepts.
A weakened immune system. It can come from an illness, such as HIV or some blood cancers, or from medicines that turn the immune system down, for example after an organ transplant or for an autoimmune disease; steroids at higher doses count.
Read whether the line is about a condition or about medicines, and which medicines and doses it means.
Autoimmune disease
A condition in which the immune system attacks the body’s own tissues, such as rheumatoid arthritis, lupus, psoriasis, type 1 diabetes or inflammatory bowel disease.
Immunotherapy studies often leave out active autoimmune disease, and some name exceptions, such as thyroid disease on replacement hormone. Check the exceptions this study lists.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Corticosteroids (steroids)
Anti-inflammatory medicines such as prednisone, prednisolone and dexamethasone — not the anabolic steroids used for muscle.
Studies differ in what they allow: check which steroid medicines, routes (tablets, injections, creams, inhalers, eye drops) and doses this study accepts.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Immunosuppression
A weakened immune system. It can come from an illness, such as HIV or some blood cancers, or from medicines that turn the immune system down, for example after an organ transplant or for an autoimmune disease; steroids at higher doses count.
Read whether the line is about a condition or about medicines, and which medicines and doses it means.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Subjects assigned to the placebo group will take one placebo capsule daily within 30 minutes before breakfast throughout the 12-week intervention period.
Dietary Supplement: Placebo
Subjects assigned to each intervention group will take one capsule daily within 30 minutes before breakfast throughout the 12-week intervention period.
Dietary Supplement: BL531_low dose
Subjects assigned to each intervention group will take one capsule daily within 30 minutes before breakfast throughout the 12-week intervention period.
Dietary Supplement: BL531_high dose
Subjects assigned to each intervention group will take one capsule daily within 30 minutes before breakfast throughout the 12-week intervention period.
Dietary Supplement: LR1349_low dose
Subjects assigned to each intervention group will take one capsule daily within 30 minutes before breakfast throughout the 12-week intervention period.
Dietary Supplement: LR1349_high dose
Maltodextrin
1×10\^10 cfu/day
2.5×10\^10 cfu/day
1×10\^10 cfu/day
2.5×10\^10 cfu/day
Computer Vision Syndrome Questionnaire (CVS-Q)
The CVS-Q is a questionnaire used to assess digital eye strain associated with prolonged digital screen use. It includes 16 symptoms related to screen exposure. Total scores are classified as 0-5 (none/minimal), 6-12 (mild), 13-18 (moderate), and ≥19 (severe), with scores ≥6 indicating clinically significant digital eye strain.
Time frame: Baseline, Week 6, Week 12
Ocular Surface Disease Index (OSDI)
The Ocular Surface Disease Index (OSDI) is a 12-item questionnaire used to assess the severity of dry eye symptoms and their impact on vision-related function and daily activities. Total scores range from 0 to 100, with higher scores indicating greater symptom severity.
Time frame: Baseline, Week 6, Week 12
Basic vision examination
A comprehensive ophthalmic examination will be performed, including uncorrected distance and near visual acuity, automated refraction, presbyopia assessment, distance and near vision correction, intraocular pressure measurement, and external eye photography for conjunctival hyperemia assessment.
Time frame: Baseline and Week 12
Pupillary Response Test
Pupillary response testing will be performed using the Oculus Pentacam HR or an equivalent device to evaluate pupil size and response time under light and dark conditions. This assessment provides information on the visual system's adaptation to changes in illumination.
Time frame: Baseline and Week 12
Tear Secretion Assessment
Tear meniscus height will be measured using the OS1000 Corneal Topographer (SBM sistemi, Italy) or an equivalent device as an indicator of tear secretion.
Time frame: Baseline and Week 12
Non-Invasive Tear Break-Up Time (NIBUT)
Non-invasive tear break-up time (NIBUT) will be measured using the OS1000 Corneal Topographer (SBM sistemi, Italy) or an equivalent device to evaluate tear film stability. A shorter NIBUT is commonly associated with dry eye symptoms and digital eye strain.
Time frame: Baseline and Week 12
Corneal Tomography and Topography Analysis
Corneal tomography and topography analysis will be performed using the Oculus Pentacam HR or an equivalent device to evaluate corneal morphology, curvature, thickness, and regularity.
Time frame: Baseline and Week 12
Accommodative Function Assessment
Accommodative function will be assessed using the ARK-1s Auto Ref-Keratometer (NIDEK, Japan) or an equivalent device to evaluate the eye's focusing ability and quantify accommodative responses associated with ciliary muscle contraction and relaxation.
Time frame: Baseline and Week 12
Worth Four Dot Test
The Worth Four Dot Test will be used to assess binocular vision and fusion ability by evaluating responses to red and green visual targets, including the presence of suppression or diplopia.
Time frame: Baseline and Week 12
Started Sep 2026 (actual). Primary completion is estimated for Aug 2027, 11 months after the start.
Of 38 interventional studies with no phase under Asthenopia, half reached primary completion within 3 months of starting (the median), counting those still running; a quarter within 2 and three quarters within 9. This study's planned 11 months is above that.
How these figures are worked out, and which studies are left out of them.
From the registry record's own update history. This site started tracking changes on Sep 25, 2026; for anything earlier, see the record history on ClinicalTrials.gov ↗
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Synbio Tech Inc.