A Single-Center, Randomized, Double-Masked, Placebo and Active Controlled, Dose-Ranging Evaluation of the Duration of Action of Brimonidine Tartrate Ophthalmic Solution in the Control of Ocular Redness Induced by Conjunctival Allergen Challenge (CAC)

Study Overview
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Brief Summary
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The purpose of this study is to evaluate the safety, efficacy, and dose response of brimonidine tartrate ophthalmic solution as compared to placebo in the prevention of allergen-induced conjunctival redness using a conjunctival allergen challenge (CAC) model. It is hypothesized that low-dose brimonidine tartrate ophthalmic solution will be more effective than vehicle in the prevention of conjunctival redness induced by conjunctival allergen challenge when instilled prior to the allergen challenge.

Official Title
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A Single-Center, Randomized, Double-Masked, Placebo and Active Controlled, Dose-Ranging Evaluation of the Duration of Action of Brimonidine Tartrate Ophthalmic Solution in the Control of Ocular Redness Induced by Conjunctival Allergen Challenge (CAC)

Conditions
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Allergic Conjunctivitis

Intervention / Treatment
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* Drug: Vehicle
* Drug: Brimonidine Tartrate 0.01%
* Drug: Brimonidine Tartrate 0.025%
* Drug: Oxymetazoline HCl 0.025%


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Be at least 18 years of age; If female, cannot be not pregnant or nursing Have a positive skin test reaction to cat hair, cat dander, grasses, ragweed, dog dander, cockroach, dust mite, and/or trees within the past 24 months; Have a calculated best corrected visual acuity of 0.6 logMAR or better in each eye as measured using an ETDRS chart; Exclusion Criteria: Have known contraindications or sensitivities to the use of any of the study medications(s) or their components; Have any ocular condition that, in the opinion of the investigator, could affect the subject's safety; Have a presence of active ocular infection; Use specified disallowed medications during the study or appropriate pre-study washout period; Have any significant illness; Have planned surgery (ocular or systemic) during the trial period or within 30 days after; Have used an investigational drug or device within 30 days of the study or be concurrently enrolled in another investigational drug or device study within 30 days of the study; Be a female who is currently pregnant or nursing.

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: Prevention
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Double


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Other: Vehicle<br> | Drug: Vehicle<br>* one drop in each eye at designated visits<br>|
| Active Comparator: Brimonidine Tartrate 0.01%<br> | Drug: Brimonidine Tartrate 0.01%<br>* one drop in each eye at designated visits<br>|
| Active Comparator: Oxymetazoline HCl 0.025%<br> | Drug: Oxymetazoline HCl 0.025%<br>* one drop in each eye at designated visits<br>|
| Active Comparator: Brimonidine Tartrate 0.025%<br> | Drug: Brimonidine Tartrate 0.025%<br>* one drop in each eye at designated visits<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Conjunctival Redness |  | at specified timepoints for up to 30 minutes |