Effect of Topical Azithromycin on Tear Film Thickness in Patients With Meibomian Gland Dysfunction

Study Overview
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Brief Summary
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Meibomian gland dysfunction (MGD) is among the leading causes for dry eye syndrome (DES), affecting millions of people worldwide. We have shown in a previous study that tear film thickness (TFT) is reduced in patients with DES and that this reduction correlates with tear break up time (BUT) as well as with the severity of subjective symptoms. Even though systemic tetracyclines as well as topical azithromycin can be used for the treatment of MGD, it seems that topical azithromycin is more effective than tetracyclines and also has the advantage of better tolerability. The hypothesis of the present study is that topical treatment with azithromycin leads to a more pronounced increase in TFT compared to oral doxycycline in patients with DES caused by MGD. The objective of this study is to compare the effect of treatment with topical azithromycin or oral doxycycline on tear film thickness in patients with DES caused by MGD.

Official Title
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Effect of Topical Azithromycin on Tear Film Thickness in Patients With Meibomian Gland Dysfunction - Comparison to Oral Treatment With Doxycycline

Conditions
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Dry Eye Syndromes, Meibomian Gland Dysfunction

Intervention / Treatment
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* Drug: Azithromycin
* Drug: Doxycycline


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Men and women aged over 18 years Signs of meibomian gland plugging or expressibility of the meibomian glands. DES most likely caused by MGD, no other cause identifiable which is more likely (e.g. intake of concomitant medication that could induce DES, systemic diseases such as systemic arthritis or diabetes), as judged by the investigator Signed and dated written informed consent. History of dry eye syndrome for at least 3 months Normal ophthalmic findings except dry eye syndrome and MGD, ametropia < 6 Dpts BUT ≤ 10 seconds Exclusion Criteria: Participation in a clinical trial in the 3 weeks before the screening visit Symptoms of a clinically relevant illness in the 3 weeks before the first study day Presence or history of a severe medical condition that will interfere with the study aim as judged by the clinical investigator Sjögren's syndrome Stevens-Johnson syndrome Presence or history of a severe ocular condition that will interfere with the study aim as judged by the clinical investigator Treatment with corticosteroids in the 4 weeks preceding the study Wearing of contact lenses Topical treatment with any ophthalmic drug in the 4 weeks preceding the study except topical lubricants Ocular infection Ocular surgery in the 6 months preceding the study Pregnancy, planned pregnancy or lactating Contraindication against the use of topical azithromycin or oral doxycycline

Ages Eligible for Study
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Minimum Age: 18 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Treatment
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Single


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Azithromycin<br>Preservative-free azithromycin 15mg/g (Azyter® Augentropfen im Einzeldosisbehältnis, Thea, Clermont-Ferrand, France) one drop twice daily for two days then once daily for 26 days | Drug: Azithromycin<br>* Azithromycin 15mg/g eyedrops<br>|
| Active Comparator: Doxycycline<br>Doxycycline 100mg (Doxycycline Genericon, Genericon Pharma GmbH, Graz, Austria) twice daily for 6 weeks | Drug: Doxycycline<br>* Doxycycline 100 mg per os<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change in tear film thickness | Change in tear film thickness measured with high resolution OCT before, during and after treatment period. | 8 weeks | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change in lipid layer thickness | Change in lipid layer thickness measured with the Lipiview device before, during and after treatment period. | 8 weeks | 
| Change in break up time (BUT) | Change in tear break up time (BUT) measured with fluorescein before, during and after treatment period. | 8 weeks | 
| Change in Visual Acuity | Change in Visual Acuity assessed before, during and after treatment period. | 8 weeks | 
| Change in tear osmolarity | Change in tear osmolarity assessed before, during and after treatment period. | 8 weeks | 
| Change in Staining of the cornea with fluorescein | Change in Staining of the cornea with fluorescein assessed before, during and after treatment period. | 8 weeks | 
| Change in impression cytology | Change in impression cytology assessed before, during and after treatment period. | 8 weeks | 
| Change in Schirmer I test | Change in Schirmer I test assessed before, during and after treatment period. | 8 weeks | 
| Change in Subjective symptoms of dry eye syndrome (OSDI© questionnaire) | Change in Subjective symptoms of dry eye syndrome (OSDI© questionnaire) assessed before, during and after treatment period. | 8 weeks | 
| Change in intraocular pressure | Change in intraocular pressure assessed before, during and after treatment period. | 8 weeks | 
| Change in meibography | Change in meibography assessed before, during and after treatment period. | 8 weeks | 
| Change in conjuctival staining with lissamine green | Change in conjuctival staining with lissamine green assessed before, during and after treatment period. | 8 weeks | 
| Change in corneal sensitivity | Change in corneal sensitivity assessed before, during and after treatment period. | 8 weeks | 
| Change in signs and symptoms of meibomian gland disease (MGD) | Change in signs and symptoms of meibomian gland disease (MGD) assessed before, during and after treatment period. | 8 weeks |