Validation of the Global Allergy and Asthma European Network (GA2LEN) chamber for trials in allergy: Innovation of a mobile allergen exposure chamber.

BACKGROUND: Field clinical trials of pollen allergy are affected by the impossibility of predicting and determining individual allergen exposure because of many factors (eg, pollen season, atmospheric variations, pollutants, and lifestyles). Environmental exposure chambers, delivering a fixed amount of allergen in a controlled environmental setting, can overcome these limitations. Environmental exposure chambers are currently already used in phase 2, 3, and even 4 trials. Unfortunately, few chambers exist in the world, and this makes it difficult to perform large, multicenter clinical trials. The new Global Allergy and Asthma European Network (GA2LEN) mobile exposure chamber is a step forward because the mobility of the chamber makes it convenient for patients to participate in clinical testing. OBJECTIVE: This study was made to validate the reproducibility, sensitivity, and specificity of the results obtained in the new GA2LEN chamber. METHODS: Seventy-two adult patients (19-61 years old) with allergic rhinitis with or without asthma caused by grass pollen were included in different clinical validation tests. Total symptom scores and total nasal symptom scores were recorded at time zero (0) and every 10 minutes during exposures, along with nasal and respiratory parameters. RESULTS: Exposure tests confirmed the reproducibility between subsequent runs and the sensitivity (P < .00001 vs patients exposed to placebo) and specificity (very low score in nonallergic subjects) in the GA2LEN chamber. No adverse reactions were recorded during the tests. CONCLUSIONS: The mobility of the GA2LEN chamber provides a new, potentially effective, and safe way of generating reliable data in allergy multicenter clinical trials.

Advantages of Lissamine Green Vital Staining as an Endpoint in Dry Eye Clinical Trials.

Purpose: The absence of a standardized diagnostic method for clinical signs of Dry Eye Disease (DED) complicates clinical trials for future treatments. This paper evaluated Lissamine Green (LG) conjunctival staining as a valid, stable and modifiable endpoint for both clinical practice and clinical trials. Methods: Screening and pre-randomization data from two identically designed clinical trials for DED resulted in a pooled dataset of 494 subjects. Inclusion was based on reported symptoms, lissamine green (LG) conjunctival staining, Fluorescein (Fl) corneal and conjunctival staining, and Schirmer's Test (ST). Outcome measures were assessed based on the modifiability of LG staining to exposure to a Controlled Adverse Environment (CAE®), correlation of LG to Fl staining, relative variation of LG staining scores and Schirmer test scores, and the correlation of LG staining with symptom scores. Results: The modifiability of LG conjunctival staining to environmental exposure was demonstrated, with nasal LG and FL staining displaying the most similar percent change. Nasal LG conjunctival staining scores for subjects with ST scores of less than 8mm were significantly higher than for subjects with ST greater than 8mm. LG staining scores were more consistent (25% change from baseline threshold) than ST scores. Finally, statistically significant correlations were found between LG staining and a number of symptom scores. Conclusion: This evaluation demonstrates the superiority of the utilization of a clinical endpoint focused on ocular surface damage. The reproducibility and modifiability of LG conjunctival staining to controlled adverse environment, coupled with its significant correlation with symptoms, positions it as an exemplary clinical sign endpoint for clinical management and in clinical trials. Our findings advocate for the adoption of LG conjunctival staining as a primary endpoint in both clinical research and drug development, offering a more effective means of identifying and addressing ocular surface damage in the realm of DED.

Antihistamines in ocular allergy: are they all created equal?

Use of topical antihistamines in the treatment of allergic conjunctivitis has evolved over the past several decades as our knowledge of the nature of the underlying disease has progressed. Formulations for the eye typically employ H(1)-receptor antagonists with a dual action, both directly as competitors for histamine receptor occupancy and as mast cell-stabilizing agents. Many of these compounds also display activity against late-phase allergic symptoms. Of the newest available drugs, several have a prolonged duration of action allowing once-daily dosing. Future development is likely to focus on long-acting agents such as these and on drugs that can target additional histamine receptor subtypes.

Vigabatrin: 2008 update.

UNLABELLED: Vigabatrin (VGB) is a structural analogue of gamma-aminobutyric acid (GABA) that irreversibly inhibits GABA-transaminase (GABA-T), increasing brain levels of GABA. VGB is under assessment for treatment of infantile spasms (IS) and refractory complex partial seizures (CPS). Response can be rapid with spasm cessation following approximately 2 weeks of therapy. Patients with symptomatic tuberous sclerosis (TS) and other patients have achieved spasm cessation. Comparison with ACTH has been performed. Patients with refractory CPS have responded as well. Adverse effects and structural findings on imaging occur with VGB treatment. T2 hyperintensities within brain have been observed. Psychotic disorders or hallucinations have occurred rarely. A specific adverse effects is associated VGB, with a peripheral visual field defect (VFD) detected in some patients. Prevalence and incidence of the VGB-induced peripheral VFD varied depending on the age of the patient and the extent of exposure to VGB, with 25% to 50% prevalence in adults; the prevalence in children was 15% and retinal defect in infants ranged from 15% to 31%. A bilateral nasal defect may be the first clinical indication and may progress to a concentric, bilateral field defect observed in many affected patients; central visual acuity is almost always preserved. The earliest finding of the first abnormal field examination in adults was after 9 months of treatment; with a mean duration of VGB exposure of 4.8 years. In children, the earliest onset of a first abnormal field examination was after 11 months, with a mean time to onset of 5.5 years. The earliest sustained onset of the VGB-induced retinal defect in infants was 3.1 months. RECOMMENDATION: Cognitive, age-appropriate visual field testing is required at baseline and then repeated at intervals in patients who continue therapy. Infants are tested at baseline and at 3-month intervals for the first 18 months of treatment, and then every 6 months thereafter. Adults with CPS are tested at baseline and at 6-month intervals. To select patients who are appropriate for VGB therapy, physicians must consider the benefits of fewer seizures and improved quality of life versus the potential risk of developing a VGBinduced peripheral VFD. Effectiveness of VGB can be detected within 12 weeks of initiating therapy. There appears to be minimal risk associated with a 2- to 3-month trial of VGB to evaluate effectiveness before there is a demonstrable risk of developing the VGB-induced peripheral VFD. If patients do not have a clinical benefit from VGB within 12 weeks of treatment initiation, VGB should be discontinued. If patients have a meaningful reduction in seizures or achieve seizure freedom, then the physician and patient or caregiver must determine if the benefits outweigh the potential risk of developing a peripheral VFD. When VGB is prescribed, the patient must be closely monitored for visual field changes. In cases where spasm or seizure improvement is not achieved within 12 weeks of initiation, VGB should be discontinued. In cases where complete spasm cessation, seizure control, or meaningful improvement is achieved within 12 weeks, continued treatment with VGB is warranted; subsequent periodic monitoring for the peripheral VFD is necessary and should be used to mitigate the risk of the defect. The risk of developing the peripheral VFD with short-term exposure seems to be low, therefore, VGB is an appropriate option for patients with IS or refractory CPS who receive a clinical benefit from its effectiveness, given the clinical consequences of uncontrolled seizures and spasms.

Dry eye in 2008.

PURPOSE OF REVIEW: Although researchers continue to investigate the multifarious etiologic, anatomical, physiological, and pathological factors of dry eye, successful treatment remains a challenge. RECENT FINDINGS: Dry eye prevalence is substantial across populations and the term 'dry eye' is used to describe numerous causes and varied pathophysiologies. Advanced study of the physiological aspects of the ocular anatomy (e.g. cornea and conjunctiva, tear film, eyelids) allows improved understanding of the mechanisms involved in dry eye and the impact of different causes on these entities. Sophisticated diagnostics are being developed to efficiently identify dry eye. Management options include a variety of novel agents in the pipeline. SUMMARY: The development of improved etiological understanding and diagnostics for dry eye, as well as emerging therapeutics, will likely allow targeted therapy in the future.

An Alternative Psychophysical Diagnostic Indicator of the Aging Eye.

PURPOSE: Impaired adaptation to changes in lighting levels as well as mesopic visual function is a common complaint in those over the age of 65. The use of photostress is a well-established method to test the adaption rate and the response of the visual cycle. In this study, we test visual function recovery to mesopic luminance stimuli following a long duration photostress in young and elderly subjects. If successful in strongly differentiating aging macular function, these methods may also be useful in the study of pathologies such as age-related macular degeneration. METHODS: A group of 12 older normal subjects (mean age 75.1 ± 4.79) and a control group of 5 younger normal subjects (mean age 26.2 ± 4.19) were subjected to macular photostress using the OraLux photostress system. The OraLux system provides a diffuse light source bleaching 84% of cone photopigment while maintaining an exposure safety factor of 200 times less than the maximum safe exposure. After each photostressing session, macular recovery was tracked using a foveal, variable contrast, flickering stimulus of mean luminance in the high mesopic range. Recovery was tracked for 300 seconds. The endpoint was time to recovery to each individual's baseline sensitivity as determined by two static sensitivity trials prior to photostress. RESULTS: Proportional hazards analysis of recovery time yielded a statistically significant difference between the older group and the young group (HR = 0.181; p=0.0289). The estimated hazard ratio of 0.181 indicates that older subjects return to baseline at less than one-fifth the rate of younger subjects. The hazards ratio remained statistically significant after adjusting for visual acuity (HR = 0.093; p=0.0424). CONCLUSION: Photostress recovery of flicker sensitivity under mesopic conditions is a strong differentiator of aging macular function. This agrees with subject-reported complaints in reduced luminance conditions after exposure to bright lights such as night driving. The qualitative similarity between the aging retina and changes in early AMD suggests that flicker recovery following photostress may be useful as a surrogate endpoint in AMD clinical trials.

Iodixanol nasal solution reduces allergic rhinoconjunctivitis signs and symptoms in Allergen BioCube®: a randomized clinical trial.

PURPOSE: Allergic rhinitis (AR) affects ~20% of the population worldwide. The objectives of this study were to evaluate the safety and efficacy of iodixanol nasal solution (Nasapaque) for AR treatment, using the Allergen BioCube® (ABC®), an environmental exposure unit. Iodixanol is a commonly used contrast media agent that shows efficacy on the signs and symptoms of AR. PATIENTS AND METHODS: Seventy-three adult subjects with AR were randomized to iodixanol or placebo treatment in a double-masked efficacy and safety study conducted outside of ragweed pollen season. In-office treatment was administered after BioCube® ragweed pollen exposure, and again 8 days later prior to ragweed exposure. Nasal and ocular efficacy and safety assessments were conducted before and after treatment. RESULTS: Iodixanol treatment resulted in statistically significantly lower total nasal symptom scores as compared to placebo at several time points post-treatment and ABC exposure. Individual nasal and ocular symptoms, notably nasal itching and ocular itching, showed evidence of lower scores in the iodixanol group. Peak nasal inspiratory flow (PNIF) improved (9%-16%) with iodixanol from baseline as compared to PNIF in the placebo group which ranged from 3% worsening to improvement of 2%. Few (9) adverse events occurred. CONCLUSION: Iodixanol nasal solution demonstrated efficacy for relief of several nasal and ocular allergic rhinoconjunctivitis signs and symptoms, and was safe and well tolerated in this early Phase II exploratory trial. Further studies with iodixanol are warranted. Allergy challenge models such as the ABC provide valuable assessments of allergen exposures and drug efficacies. STUDY IDENTIFICATION NUMBER: NCT02377895.

Bioequivalence of two formulations of ketotifen fumarate ophthalmic solution: a single-center, randomized, double-masked conjunctival allergen challenge investigation in allergic conjunctivitis.

BACKGROUND: Ketotifen fumarate ophthalmic solution 0.025% (reference formulation), a topical mast cell stabilizer/antihistamine combination, has been found to be effective and well tolerated in the prevention of ocular itching associated with allergic conjunctivitis (AC). A recently developed formulation of ketotifen fumarate ophthalmic solution 0.025% (test formulation) contains the same active ingredient in the same concentration as the reference formulation, is intended for twice-daily dosing, and may provide a treatment option in patients with AC. OBJECTIVE: The aim of this study was to determine the clinical bioequivalence of the test and reference formulations using a conjunctival allergen challenge (CAC) model. METHODS: This prospective, randomized, double-masked, active- and placebo-controlled CAC study was conducted in a clinical setting (ORA Clinical Research and Development, North Andover, Massachusetts). Patients aged <18 years who had AC, a successful allergen challenge during screening and allergen confirmation visits, a history of ocular allergies, and positive skin-test reactivity were enrolled. Patients' eyes were randomized to receive the test or reference formulation or inactive vehicle (1 drop of 1 study medication per eye per visit). The primary efficacy end point was ocular itching, and the secondary end points were ocular redness, chemosis, lid swelling, tearing, and mucous discharge. Efficacy was assessed following challenge at 8 hours and 15 minutes after instillation. The test and reference formulations were considered bioequivalent if the 95% CIs for the differences in mean ocular itching scores between the 2 groups were within the range of 0.40 to 0.40. RESULTS: There were 108 patients enrolled (61 men, 47 women; mean age, 42 years; 91.7% white). The test and reference formulations both yielded clinically significant results compared with placebo in the prevention of ocular itching at CACs performed 8 hours and 15 minutes after instillation. At the 8-hour posttreatment CAC, the mean ocular itching scores for test formulation-treated eyes were 1.158, 1.265, and 1.305 units lower, respectively, than for eyes at 3, 5, and 7 minutes that were administered placebo. At 15-minute posttreatment CAC, the mean ocular itching scores for reference formulation-treated eyes at 3, 5, and 7 minutes were 1.481, 1.622, and 1.565 units lower, respectively, than for eyes that were administered placebo. With regard to the primary and secondary efficacy variables, no statistically significant differences were observed between test and reference formulations at any post-CAC time point. CONCLUSIONS: In this population of patients with AC, the test formulation of ketotifen fumarate ophthalmic solution 0.025% met criteria for bioequivalence to the reference formulation, as established by the protocol. The test and reference formulations were well tolerated in the population studied.

Clinical cure of bacterial conjunctivitis with azithromycin 1%: vehicle-controlled, double-masked clinical trial.

PURPOSE: To analyze the effect of azithromycin 1% ophthalmic solution in DuraSite (InSite Vision, Inc, Alameda, California, USA) on bacterial conjunctivitis. DESIGN: Prospective, randomized, vehicle-controlled, parallel-group, double-masked multicenter clinical study. METHODS: Eligible male or female participants with a clinical diagnosis of acute bacterial conjunctivitis were randomized to either 1% azithromycin in DuraSite or vehicle for five days. Infected eyes were dosed twice daily on days 1 and 2 and once daily on days 3 through 5. Conjunctival cultures were obtained at baseline, visit 2 (day 3 or 4), and visit 3 (day 6 or 7). The primary end point was clinical resolution of signs and symptoms (rating of zero on ocular discharge, bulbar and palpebral injection) at visit 3. Efficacy measures were clinical resolution and bacterial eradication as evaluated in the per-protocol population. Safety was assessed by adverse events, slit-lamp findings, and ophthalmoscopy. RESULTS: Two hundred and seventy-nine participants (n = 130, 1% azithromycin in DuraSite; n = 149, vehicle), age one to 96 years, were evaluated for efficacy. Clinical resolution with azithromycin ophthalmic solution was statistically significant compared with that of vehicle (P = .030) at visit 3. Bacterial eradication rates with azithromycin ophthalmic solution reached 88.5% at visit 3 (P < .001) and included some pathogens resistant to azithromycin in vitro. Overall, adverse event rates were similar in both treatment groups. CONCLUSIONS: Azithromycin 1% ophthalmic solution in DuraSite showed statistically significant differences in clinical resolution and bacterial eradication rates when compared with vehicle. Because it was well tolerated in this population, it may be a viable treatment option for children and adults with bacterial conjunctivitis.

Olopatadine 0.2% ophthalmic solution: the first ophthalmic antiallergy agent with once-daily dosing.

BACKGROUND: Olopatadine 0.2% is the first topical ophthalmic antihistamine/mast cell stabilizer indicated for once-daily dosing. OBJECTIVE: This review provides a comprehensive description of the pharmacology of the olopatadine molecule, as well as of the clinical efficacy, tolerability, and safety of olopatadine 0.2% ophthalmic solution. METHODS: References cited in this review were obtained from the PubMed biomedical literature database. Also included were several posters presented at nationally renowned ophthalmology-related conferences. RESULTS/CONCLUSION: Olopatadine 0.2% was found to be a safe and effective medication for the reduction of itching with a duration of action of up to 24 h. The added convenience of a once-a-day dosing regimen is a major advancement in this drug class.

Blink: Characteristics, Controls, and Relation to Dry Eyes.

Blink is a complex phenomenon that is profoundly affected by diverse endogenous and exogenous stimuli. It has been studied in the context of cognition, emotional, and psychological states, as an indicator of fatigue and sleepiness, particularly in the automobile and transportation industry, in visual tasking, and finally, as it relates to tear film stability and ocular surface health. The fact that it is highly variable and has input from so many sources makes it very difficult to study. In the present review, the behavior of blink in many of these systems is discussed, ultimately returning in each instance to a discussion of how these factors affect blink in the context of dry eyes. Blink is important to ocular surface health and to an individual's optimal functioning and quality of life. Disturbances in blink, as cause or effect, result in a breakdown of tear film stability, optical clarity, and visual function.

Cone photoreceptor macular function and recovery after photostress in early non-exudative age-related macular degeneration.

PURPOSE: To identify parameters from cone function and recovery after photostress that detect functional deficits in early non-exudative age-related macular degeneration (AMD) and to determine the repeatability of these parameters. METHODS: Cone-mediated visual function recovery after photostress was examined in three groups of subjects: young normal subjects (ages 20-29; N=8), older normal subjects (ages 50-90; N=9), and early non-exudative AMD subjects (ages 50-90; N=12). Eight AMD and four normal subjects were retested 1 year after the initial evaluation. Early Treatment Diabetic Retinopathy Study (ETDRS) visual acuity (VA) and parameters of cone function (baseline cone sensitivity and cone recovery half-life following photobleach) were measured and compared between AMD and normal subjects. Short-term repeatability was assessed for each subject's initial evaluation. Long-term repeatability was assessed by comparing outcomes from the initial evaluation and 1-year follow-up. RESULTS: The mean baseline cone threshold was significantly worse in subjects with early AMD compared to older normal subjects (-1.80±0.04 vs -1.57±0.06 log cd/m2p=0.0027). Moreover, the baseline cone threshold parameter exhibited good short-term (intraclass correlation coefficient [ICC]=0.88) and long-term (ICC=0.85) repeatability in all subjects. The cone intercept parameter and ETDRS VA were not significantly different between AMD and older normal subject groups. Cone recovery half-life was significantly different between older normal and AMD subject groups (p=0.041). Neither ETDRS VA nor cone function parameters were significantly different for any group at the 1-year follow-up. CONCLUSION: The baseline cone threshold shows potential as a novel parameter to assess visual dysfunction in early AMD. This outcome consistently detected deficits in AMD subjects, and differentiated them from age-matched controls with high test-retest repeatability.

Efficacy of once-daily olopatadine 0.2% ophthalmic solution compared to twice-daily olopatadine 0.1% ophthalmic solution for the treatment of ocular itching induced by conjunctival allergen challenge.

Olopatadine 0.1% (Patanol) and olopatadine 0.2% (Pataday) ophthalmic solutions are topical ocular anti-allergic agents with antihistaminic and mast cell stabilizing properties. The efficacy of two doses of olopatadine 0.1% was compared to one dose of olopatadine 0.2% in the prevention of ocular itching associated with allergic conjunctivitis over 24 hours. This double-masked conjunctival allergen challenge (CAC) study found no significant difference in the mean itching scores between two drops of olopatadine 0.1% and one drop of olopatadine 0.2%. Both showed significant activity at the 24-hour time point and were statistically superior to placebo. No adverse events occurred while on drug therapy.

Technical and clinical validation of the Allergen BioCube® for timothy grass.

INTRODUCTION: Field studies for allergic rhinitis (AR) commonly have inconsistent allergen concentrations and subject exposure patterns due to varying environmental conditions and subject behaviors. A technical and clinical validation study was conducted for the Allergen BioCube® using timothy grass to confirm uniform allergen concentration and clinically relevant subject symptom responses. METHODS: Allergen concentrations were verified by laser particle counts. Subjects (N = 14) with positive skin test reactions and no symptoms at screening received four 3-h timothy grass exposures in the BioCube over consecutive days. Subjects evaluated nasal itching, sneezing, rhinorrhea, and nasal congestion while in the BioCube; Total Nasal Symptom Score (TNSS) was computed. Peak Nasal Inspiratory Flow (PNIF), Peak Expiratory Flow Rate (PEFR), sIgE blood tests, and Nasal Inflammation Score (NIS) were assessed. A correlation analysis was conducted for mean sIgE, skin test, and TNSS. RESULTS: Uniform timothy grass concentrations were achieved in the BioCube, both spatially and temporally, at all subject positions. Mean TNSS increased substantially from pre-exposure levels (0.36 ± 0.74 to 1.86 ± 2.14) to maximums of 7.07 ± 2.76 at 1.5 h and 6.71 ± 2.70 at 3 h BioCube exposure. Twelve (86%) subjects had TNSS increases ≥6 units. PNIF decreased 12-24% from baseline at 3-h BioCube exposure. NIS increased (baseline = 0) to 3.7 (maximum score = 4). A low/moderate correlation (r = 0.485) occurred between mean sIgE blood levels and mean skin tests; neither sIgE or skin tests correlated with mean TNSS. However, subjects with high skin test scores or positive blood IgE tended to also have higher TNSS. CONCLUSIONS: The Allergen BioCube achieved technical and clinical validation for uniform timothy grass concentration and clinically meaningful AR sign and symptom responses. The Allergen BioCube can be used to assess the efficacy of therapies for reduction of AR signs and symptoms resulting from grass exposure.

Use of the Controlled Adverse Environment (CAE) in Clinical Research: A Review.

The many internal and external factors that contribute to the pathophysiology of dry eye disease (DED) create a difficult milieu for its study and complicate its clinical diagnosis and treatment. The controlled adverse environment (CAE®) model has been developed to minimize the variability that arises from exogenous factors and to exacerbate the signs and symptoms of DED by stressing the ocular surface in a safe, standardized, controlled, and reproducible manner. By integrating sensitive, specific, and clinically relevant endpoints, the CAE has proven to be a unique and adaptable model for both identifying study-specific patient populations with modifiable signs and symptoms, and for tailoring the evaluation of interventions in clinical research studies.

Vehicle-Controlled, Phase 2 Clinical Trial of a Sustained-Release Dexamethasone Intracanalicular Insert in a Chronic Allergen Challenge Model.

PURPOSE: To evaluate the efficacy and safety of a sustained-release dexamethasone intracanalicular insert (Dextenza™) in a model of allergic conjunctivitis. METHODS: This was a randomized, double-masked, vehicle-controlled, Phase 2 study. Subjects had to have a positive conjunctival allergen challenge (CAC) reaction to allergen (bilateral +2 itching and redness on 5-point, 0-4 scales) at Visit 1, and for 2 of 3 time points on subsequent visits. Subjects who met entry criteria were randomized to receive Dextenza or PV (vehicle insert). Challenges occurred over 42 days, with efficacy assessed at 14 (primary endpoint visit), 28, and 40 days postinsertion. Outcome measures included the evaluation of ocular itching, redness, tearing, chemosis, eyelid swelling, rhinorrhea, and congestion. RESULTS: Twenty-eight subjects completed the study in the Dextenza group and 31 in the vehicle group. At 14 days postinsertion, Dextenza was statistically superior to PV, with least square mean differences for ocular itching of -0.76, -0.97, and -0.87 at 3, 5, and 7 min post-CAC, and for conjunctival redness of -0.46, -0.66, and -0.68 at 7, 15, and 20 min post-CAC. Clinical significance, defined as a 1-U decrease from PV, was not met for primary efficacy. Secondary endpoints, including number of subjects reporting itching and conjunctival redness, indicated superior performance of Dextenza compared with vehicle. Eleven Dextenza-treated (35.5%) and 10 vehicle-treated (30.3%) subjects each experienced a single adverse event. CONCLUSION: This Phase 2 study demonstrated preliminary efficacy and safety data of Dextenza for treatment of allergic conjunctivitis.

Dynamic Sensitivity of Corneal TRPM8 Receptors to Menthol Instillation in Dry Eye Versus Normal Subjects.

PURPOSE: To assess the sensitivity of corneal cold receptors to a known transient receptor potential melastatin 8 (TRPM8) agonist, menthol, in dry eye and normals, and to determine whether factors such as disease duration or age affect responses. METHODS: Dry eye disease (DED) (N = 33) and normal (N = 15) subjects were randomly assigned to receive Rohto® Hydra (0.01% menthol) or Systane® Ultra treatments (OU) in a prospective, double-blind, crossover study. DED subjects had documented disease and symptom response scores >2 on a 0- to 5-point scale. Normals had no history of DED and scores <2 on the same scale. Endpoints included mean cooling score (0 = not cool and 10 = very cool) evaluated at 0, 0.5, 1, 2, 3, and 4 min post-instillation, sum cooling scores (5 time points, range 0-60), and ocular signs and symptoms. RESULTS: Mean (±SD) ages were similar, 62.2 ± 8.6-year (DED) versus 53.5 ± 7.6-year (normal). Corneal sensitivity scores were not different between groups. Mean cooling scores at 0.5-4 min post-menthol instillation were significantly higher in DED subjects (P ≤ 0.03). Sum cooling scores were significantly higher (P = 0.04) in DED subjects with a disease duration <10 years (N = 18, 28.3 ± 2.58) versus ≥10 years (N = 15, 20.2 ± 2.76). Age did not affect cooling response in either group. CONCLUSION: DED subjects had greater sensitivity to cold than normal subjects. DED duration, and not age, was critical to cooling sensitivity. The finding that cooling scores were higher in subjects with DED for less than 10 years compared to more than 10 years suggests that corneal cold receptor sensitivity decreases as the duration of DED increases.

Technical and clinical validation of an environmental exposure unit for ragweed.

BACKGROUND: Allergic rhinitis is a common condition, with ragweed pollen one of the more prevalent aeroallergens. Environmental exposure units such as the Allergen BioCube® are valuable models for clinical allergy studies. A study was conducted to validate the Allergen BioCube for uniform ragweed pollen concentrations and clinically relevant sign and symptom responses to ragweed exposure. METHODS: Ragweed pollen concentrations were measured on 3 consecutive days in the Allergen BioCube and verified by Rotorod collection and continuous laser particle count measurements. Subjects (N=10) were exposed to ragweed pollen in the BioCube for 3 hours per day for 3 consecutive days. Subjects assessed their nasal itching, sneezing, rhinorrhea, and nasal congestion during each BioCube exposure; total nasal symptom score was computed. Peak nasal inspiratory flow was also assessed during BioCube exposure. RESULTS: Uniform ragweed pollen concentrations were obtained throughout each of the 3-hour testing periods in the Allergen BioCube, both spatially and temporally, at all subject positions, with a low mean standard deviation of 10%. Pronounced increases in mean total nasal symptom scores (6.7±0.94 to 7.6±0.86, last 90 minutes of exposure) occurred for all three BioCube ragweed pollen exposure visits. Mean peak nasal inspiratory flow decreased 24% at 3 hours of BioCube exposure on Day 3. No safety issues of concern occurred in this study. CONCLUSION: The Allergen BioCube achieved technical and clinical validation for ragweed allergen. Ragweed pollen concentration was uniform both temporally and spatially. Allergic rhinitis signs and symptoms were induced in subjects during exposure to ragweed in the BioCube at clinically meaningful levels for allergy studies.

Diurnal Tracking of Blink and Relationship to Signs and Symptoms of Dry Eye.

PURPOSE: To assess diurnal changes in the signs and symptoms of dry eyes and their relationship to diurnal interblink interval (IBI) in normal subjects and in subjects with dry eye. METHODS: Blink data were collected from 9:00 AM to 8:00 PM during 2 days of normal activity using an electrocardiogram monitoring device. All subjects recorded ocular discomfort (0-5 scale) and primary activity hourly each day in a diary. Inferior and central fluorescein staining was graded by slit lamp (0-4) at the start and end of each day. Blink activity was detected using an algorithm based on recognition of the waveform corresponding to the kinematic properties of the blink signal. RESULTS: Normal subjects (N = 12) reported negligible symptoms, and results did not show a diurnal change in group hourly IBI. Mean daily IBI for the group with dry eye (N = 15) (4.63 ± 1.63 s) was shorter than that for the normal group (5.28 ± 1.48 s) (P = 0.0483). Correlation of diurnal symptoms and mean hourly IBI was relatively weak (r = -0.248). A repeated-measures model found IBI to be significantly associated with the time of day (P = 0.0028). Inferior corneal staining showed a small but significant diurnal increase for both normal group and group with dry eyes. CONCLUSIONS: Diurnal blink tracking reveals significant trending with symptoms. Diurnal change in IBI may be an appropriate surrogate for symptoms in the study of dry eye.

Effects of a new formulation of olopatadine ophthalmic solution on nasal symptoms relative to placebo in two studies involving subjects with allergic conjunctivitis or rhinoconjunctivitis.

BACKGROUND: A new formulation of olopatadine hydrochloride ophthalmic solution (olopatadine 0.2%) was evaluated in two separate, randomized, placebo-controlled, double-masked, hybrid environmental studies intended to determine efficacy and safety in subjects with histories of seasonal allergic conjunctivitis or rhinoconjunctivitis. DESIGN AND METHODS: In these 10- and 12-week trials (conducted April-August 2003 and July-December 2001, respectively), subjects assessed their ocular signs and symptoms. Additionally, subjects in the 10-week trial evaluated the frequency of their nasal symptoms while subjects in the 12-week trial evaluated both the frequency and severity of their nasal symptoms. The two trials had a combined enrollment of 500 subjects (217 males, 283 females) including 44 children aged 10-17 years; the combined population was 81.4% Caucasian, 9.2% Black, 2% Hispanic, and 7.4% other. Daily throughout these studies, either ragweed (fall study) or grass (spring study) pollen counts were obtained from each investigative center. Slope analyses were conducted on the nasal symptom assessments by pollen count. RESULTS: The nasal results from the two clinical trials are presented herein. In the fall study, relative to placebo, olopatadine 0.2% significantly reduced the frequency of pollen effects on sneezing (p = 0.0355) and itchy nose (p = 0.0032), and reduced the severity of pollen effects on sneezing (p = 0.0451), itchy nose (p = 0.0178), and runny nose (p = 0.0327). In the spring study, olopatadine 0.2% significantly reduced the frequency of pollen effects on sneezing (p = 0.0017) and runny nose (p = 0.0031) relative to placebo. In the fall trial, 2 subjects discontinued due to treatment-related adverse events (tachycardia and dry eye), while in the spring study, no subject discontinued due to a treatment-related adverse event. No subject in either study suffered a treatment-related serious adverse event. CONCLUSIONS: For the subjects enrolled in these studies, olopatadine 0.2% appeared to be safe, well-tolerated, and effective in significantly reducing the frequency and/or severity of some effects of pollen on nasal symptoms.