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BACKGROUND: Bronchial thermoplasty (BT) is a bronchoscopic procedure for patients with severe uncontrolled asthma, but randomized controlled studies of its efficacy in severe asthma with frequent exacerbations are lacking. The current aim was to assess BT efficacy in this patient population. METHODS: Thirty patients with asthma (GINA 5) who had experienced at least four severe exacerbations in the preceding year were randomized to BT (n = 15) or control groups (n = 15). All patients had four follow-up visits over the following 15 months, corresponding to 3, 6, 9, and 12 months after the last procedure for the BT group. The primary outcome was number of exacerbations at 15 months after inclusion (i.e. 12 months after bronchial thermoplasty). RESULTS: All but three patients had received an asthma biologic without receiving benefit. In the year preceding enrollment, patients in the BT group had an average of five exacerbations, compared with six among controls. For patients in the BT group, oral steroid intake was 9.3 mg/d, compared with 11.0 mg/d among controls. The BT group had 1.58 fewer severe exacerbations (mean, 6.09) compared with controls (mean, 8.28) in the 12-month period after the therapy (p = 0.047). Oral steroid intake during follow-up after BT was significantly lower in the BT group (ratio vs controls: 0.61; p = 0.0002). Quality-of-life measures between inclusion and the last visit were significantly improved in the BT group, but not among controls. Few mild to moderate adverse events were reported, and all were controlled within days. CONCLUSION: In patients with severe asthma and frequent severe exacerbations, BT significantly decreased the rate of severe exacerbations and oral steroid intake and led to improved quality of life during the 15 months after inclusion. BT appears to offer a therapeutic option for severe asthma with frequent exacerbations.
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BACKGROUND: Assessment of IgE-mediated sensitization to flour allergens is widely used to investigate flour-induced occupational asthma. The diagnostic efficiency of detecting specific IgE antibodies (sIgEs) against wheat and rye flour, however, has not been thoroughly compared with other diagnostic procedures. OBJECTIVE: We sought to evaluate the diagnostic accuracy of sIgE against wheat and rye compared with specific inhalation challenge (SIC) with flour as the reference standard. METHODS: This retrospective multicenter study included 264 subjects who completed an SIC with flour in eight tertiary centers, of whom 205 subjects showed a positive SIC result. RESULTS: Compared with SIC, sIgE levels of 0.35 kUA/L or greater against wheat and rye provided similar sensitivities (84% to 85%, respectively), specificities (71% to 78%), positive predictive values (91% to 93%), and negative predictive values (56% to 61%). Increasing the threshold sIgE value to 5.10 kUA/L for wheat and to 6.20 kUA/L for rye provided a specificity of 95% or greater and further enhanced the positive predictive value to 98%. Among subjects with a positive SIC, those who failed to demonstrate sIgE against wheat and rye (n = 26) had significantly lower total serum IgE level and blood and sputum eosinophil counts and a lesser increase in postchallenge FeNO compared with subjects with a detectable sIgE. CONCLUSION: High levels of sIgE against wheat and/or rye flour strongly support a diagnosis of flour-induced occupational asthma without the need to perform an SIC. The absence of detectable sIgE against wheat and rye in subjects with a positive SIC seems to be associated with lower levels of TH2 biomarkers.
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Asma Ocupacional , Harina , Inmunoglobulina E , Secale , Triticum , Humanos , Secale/inmunología , Secale/efectos adversos , Inmunoglobulina E/sangre , Inmunoglobulina E/inmunología , Masculino , Asma Ocupacional/diagnóstico , Asma Ocupacional/inmunología , Femenino , Harina/efectos adversos , Adulto , Estudios Retrospectivos , Triticum/inmunología , Triticum/efectos adversos , Persona de Mediana Edad , Alérgenos/inmunología , Pruebas de Provocación Bronquial , Sensibilidad y Especificidad , Hipersensibilidad al Trigo/inmunología , Hipersensibilidad al Trigo/diagnósticoRESUMEN
BACKGROUND: An innovation to better manage cat-allergic patients utilises anti-Fel d 1 IgY antibodies to neutralise Fel d 1 after its production by the cat. However, there is no published study showing its clinical efficacy in humans in a home setting. A longitudinal, open-label, proof-of-concept study was carried out to approach clinical efficacy of the cat food in cat-allergic patients. METHODS: After a baseline evaluation, the cats ate only the cat food for the following 4 months. Daily evaluation of efficacy was performed for 2 weeks at baseline and after 1, 2 and 3 months of intervention for periods of 2 weeks. The MASK-air app was used daily to assess symptoms, work productivity and medications. RESULTS: Of the 49 patients screened, 42 were followed up and 33 (78.5%) reported MASK-air data at all 3 evaluation periods. The primary end point (visual analogue scale [VAS] for global allergy symptoms) was significantly improved (p < 0.0001). All symptoms (VAS nose, eye, and asthma), VAS work and the combined symptom-medication score significantly improved after 1 month. The percentage of uncontrolled days (VAS>20/100) decreased from 64% at baseline to 35% at 1 month (p < 0.0001) and 14% at 3 months. A sensitivity analysis in patients with uncontrolled disease at baseline found similar results. DISCUSSION: A cat diet containing anti-Fel d 1 antibodies was able to (i) show decreased allergic symptoms and related outcomes, (ii) inform the design and feasibility of future studies with a control arm and (iii) estimate the sample size of the study. STUDY REGISTRATION NUMBER: clinicaltrials.gov: NCT05656482.
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BACKGROUND: The impact of allergic rhinoconjunctivitis on the early (EAR) and late asthmatic response (LAR) has yet to be assessed during optimal allergen exposure conditions. OBJECTIVE: We aimed to assess predictive factors of the EAR and LAR and to evaluate the relation between rhinitis, conjunctivitis and asthma induced by cat allergen exposure in an environmental exposure chamber (EEC). METHODS: Data from two cohort studies involving asthmatic patients with cat allergy who performed a cat allergen exposure challenge in ALYATEC EEC were analysed. Spirometry, visual analogue scale (VAS) for asthma, VAS for rhinitis, Total Nasal Symptoms Score, Total Ocular Symptoms Score (TOSS), Rhinoconjunctivitis Total Symptoms Score and Abelson score were used to assess asthma, rhinitis and conjunctivitis during and after exposure. RESULTS: An EAR occurred in 65.1% of patients, 32.1% of whom had a LAR. The diameter of the prick test to cat allergens and non-specific bronchial hypersensitivity level were independent risk factors for EAR (p < .05). No independent risk factors for LAR were identified. Rhinoconjunctivitis severity during exposure correlated with the asthma VAS during EAR and LAR (p < .05). Allergen exposure time needed to trigger an EAR correlated with the Abelson score during exposure (p < .05). The asthma VAS and TOSS during exposure correlated with faster LAR occurrence (p < .05). CONCLUSION: Prick test size and non-specific bronchial hypersensitivity level were confirmed as independent predictive factors of EAR during allergen exposure in an EEC. This study demonstrated the relation between the severity of rhinitis, conjunctivitis and asthma induced by allergen exposure for both EAR and LAR.
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Alérgenos , Asma , Conjuntivitis Alérgica , Exposición a Riesgos Ambientales , Índice de Severidad de la Enfermedad , Gatos , Humanos , Asma/inmunología , Asma/etiología , Asma/diagnóstico , Femenino , Masculino , Adulto , Exposición a Riesgos Ambientales/efectos adversos , Conjuntivitis Alérgica/inmunología , Conjuntivitis Alérgica/etiología , Conjuntivitis Alérgica/diagnóstico , Animales , Alérgenos/inmunología , Persona de Mediana Edad , Pruebas Cutáneas , Adolescente , Rinitis Alérgica/inmunología , Rinitis Alérgica/etiología , Rinitis Alérgica/diagnóstico , Factores de Riesgo , Adulto JovenRESUMEN
Background: House dust mite (HDM)-induced allergic rhinitis (AR) is a major cause of allergic respiratory disease. The efficacy and safety of the 300 IR HDM sublingual immunotherapy (SLIT) tablet in patients with moderate-to-severe HDM-AR was confirmed in a large, international, phase 3 randomized controlled trials (RCTs). Here, we analyzed the results in the European population. Methods: Data from 91 European centers that participated in the international, double-blind, RCT (EudraCT 2014-004223-46, NCT02443805) with the 300 IR HDM SLIT tablet versus placebo over 12 months were analyzed post hoc. The treatment effect in European adults and adolescents was notably assessed through the European Academy of Allergy and Clinical Immunology (EAACI)-recommended combined symptom and medication score (CSMS0-6, pre-defined endpoint) and the total combined rhinitis score (TCRS0-24, post hoc endpoint, also balanced) during the primary evaluation period (4 weeks at the end of treatment period) using analysis of covariance (ANCOVA). Results: There were 818 patients who comprised the modified full analysis set in Europe. Over the primary period, the differences in CSMS0-6 and TCRS0-24 between the 300 IR and placebo groups were statistically significant (p < 0.0001): -0.32 (95%CI [-0.46; -0.17]) and -1.28 (95%CI [-1.63; -0.94]), respectively, with relative differences of -20.9% and -21.2%. All post hoc and the rhinoconjunctivitis quality of life endpoints were significantly improved with 300 IR versus placebo. The 300 IR HDM tablet was generally well tolerated. Conclusion: This RCT sub-analysis confirmed the 300 IR HDM SLIT tablet is an effective and safe treatment for European adults and adolescents with HDM-AR with clinically meaningful benefits from the patients' perspective. Trial registration: NCT02443805. Registered on April 29, 2015./EudraCT 2014-004223-46. Registered on September 16, 2015.
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Background: Asthma is a multifactorial chronic disease, whose most frequent etiology is allergy, especially to Blomia tropicalis. In French Guiana, the childhood prevalence of Blomia T sensitization is unkwown. The aim of this study was to determine the proportion of sensitization to Blomia T and other mites in asthmatic children, and to describe the characteristics of childhood asthma in French Guiana. Methods: A retrospective cohort study focused on children from 0 to 18 years of age, followed for asthma at the Department of Pediatrics of the Cayenne Hospital Center in French Guiana. All asthmatic children followed by the same paediatric allergist were systematically skin-tested with Bt total extract, and Bt-specific IgE tests were additionally performed to confirm specific sensitization. All follow-up variables were collected from medical records. The outcome was sensitization to Blomia tropicalis and other allergens, and the explanatory variables were those of asthma follow-up. Patients were categorized into Blomia tropicalis sensitization yes/no. Logistic regression analysis was used to assess the relationship between follow-up variables and the outcome. Results: 302 patients were followed: 177 cases of allergic rhinitis, 135 allergic conjunctivitis, 105 atopic dermatitis, 153 food allergy, and 14 cases of drug allergy. Poly-allergy (respiratory, food, skin, and medicinal) was present in 239 children. There were 158 children followed for asthma, of whom 103 (65%) were sensitized to Blomia tropicalis. The median age of the asthmatic children sensitized to Blomia tropicalis was 7 years, and 3 years for those who were not sensitized (p < 0.001). Among the girls (n = 58), 67% were sensitized to Blomia; 97 (92%) asthmatic children co-sensitized to Blomia tropicalis, Dermatophagoides pteronyssinus, and Dermatophagoides farinae. Multivariate analysis showed that the childhood asthma in French Guiana is characterized by a median age of 7 years (p < 0.001), a high prevalence of Blomia tropicalis (p < 0.001), co-sensitization to other mites (p < 0.001), and a high prevalence of co-sensitization to cockroaches (p = 0.006). The area under the ROC curve was close to 0.9, confirming the quality of our model. Conclusion: In French Guiana, asthma is characterized by a high prevalence of Blomia tropicalis sensitization.
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Background: Pollen variation can affect field study data quality. Nasal allergen challenge (NAC) is considered the gold standard for evaluating allergic rhinitis, while environmental exposure chambers (EECs) are mainly used in phase 2 drug development studies. We aimed to study birch-induced allergic rhinitis under 3 different conditions. Methods: This study included 30 participants allergic to birch pollen, based on birch skin prick test, specific immunoglobulin E (IgE), and positive NAC. Participants were exposed to placebo twice, followed by 2 consecutive 4-h birch airborne exposures, repeated on 2 occasions to evaluate reproducibility and priming effect. Nasal response was defined as total corrected nasal symptom score (ΔTNSS) ≥ 5 during NAC and EEC. The primary end-point was to measure TNSS during the last 2 h of first allergen exposure. TNSS was also analyzed during natural exposure. Results: The dose most commonly yielding positive TNSS during NAC was 175.2 ng/200 µL. Eighteen participants experienced ΔTNSS ≥5 during the last 2 h of the first exposure, whereas 21 had positive responses at all 4 exposures. Mean ΔTNSS was 1 with placebo versus 6 with birch. Exposures were reproducible, with no observed priming effect. Airborne Bet v 1 was 25 ng/m3, while the pollen measurement was 279/m3 during pollen season. TNSS reached 5 in 67.9% of participants during peak pollen season. Conclusion: EEC outcomes were similar to those obtained with NAC and natural exposure, suggesting the usefulness of EEC in allergic rhinitis studies. The primary end-point was reached, as 60% of participants experienced nasal responses.
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Búfalos , Hipersensibilidad a la Leche , Animales , Humanos , Caseínas/efectos adversos , CabrasAsunto(s)
Asma Ocupacional , Enfermedades Profesionales , Exposición Profesional , Humanos , Asma Ocupacional/diagnóstico , Platino (Metal) , Sales (Química) , Peso Molecular , Pruebas de Provocación Bronquial , Óxido Nítrico , Enfermedades Profesionales/diagnóstico , Pruebas Respiratorias , Exposición Profesional/efectos adversosRESUMEN
BACKGROUND: Validated questionnaires are used to assess asthma control over the past 1-4 weeks from reporting. However, they do not adequately capture asthma control in patients with fluctuating symptoms. Using the Mobile Airways Sentinel Network for airway diseases (MASK-air) app, we developed and validated an electronic daily asthma control score (e-DASTHMA). METHODS: We used MASK-air data (freely available to users in 27 countries) to develop and assess different daily control scores for asthma. Data-driven control scores were developed based on asthma symptoms reported by a visual analogue scale (VAS) and self-reported asthma medication use. We included the daily monitoring data from all MASK-air users aged 16-90 years (or older than 13 years to 90 years in countries with a lower age of digital consent) who had used the app in at least 3 different calendar months and had reported at least 1 day of asthma medication use. For each score, we assessed construct validity, test-retest reliability, responsiveness, and accuracy. We used VASs on dyspnoea and work disturbance, EQ-5D-VAS, Control of Allergic Rhinitis and Asthma Test (CARAT), CARAT asthma, and Work Productivity and Activity Impairment: Allergy Specific (WPAI:AS) questionnaires as comparators. We performed an internal validation using MASK-air data from Jan 1 to Oct 12, 2022, and an external validation using a cohort of patients with physician-diagnosed asthma (the INSPIRERS cohort) who had had their diagnosis and control (Global Initiative for Asthma [GINA] classification) of asthma ascertained by a physician. FINDINGS: We studied 135 635 days of MASK-air data from 1662 users from May 21, 2015, to Dec 31, 2021. The scores were strongly correlated with VAS dyspnoea (Spearman correlation coefficient range 0·68-0·82) and moderately correlated with work comparators and quality-of-life-related comparators (for WPAI:AS work, we observed Spearman correlation coefficients of 0·59-0·68). They also displayed high test-retest reliability (intraclass correlation coefficients range 0·79-0·95) and moderate-to-high responsiveness (correlation coefficient range 0·69-0·79; effect size measures range 0·57-0·99 in the comparison with VAS dyspnoea). The best-performing score displayed a strong correlation with the effect of asthma on work and school activities in the INSPIRERS cohort (Spearman correlation coefficients 0·70; 95% CI 0·61-0·78) and good accuracy for the identification of patients with uncontrolled or partly controlled asthma according to GINA (area under the receiver operating curve 0·73; 95% CI 0·68-0·78). INTERPRETATION: e-DASTHMA is a good tool for the daily assessment of asthma control. This tool can be used as an endpoint in clinical trials as well as in clinical practice to assess fluctuations in asthma control and guide treatment optimisation. FUNDING: None.
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Asma , Rinitis Alérgica , Humanos , Reproducibilidad de los Resultados , Rinitis Alérgica/diagnóstico , Rinitis Alérgica/tratamiento farmacológico , Asma/diagnóstico , Asma/tratamiento farmacológico , Encuestas y Cuestionarios , DisneaAsunto(s)
Asma , Ácaros , Humanos , Quimiocinas CC , Inmunosupresores , Receptores de Quimiocina , Linfocitos T ReguladoresRESUMEN
Biological therapies are available for the treatment of the severe allergic asthma (SAA) with blood eosinophil count ≥ 0.3 × 109/L. Several of them also showed benefits on nasal polyps (NP), one of the most frequent comorbidities of the severe asthma, but comparative studies on their effectiveness in the association SAA-NP are currently lacking. The aim of this study is to compare the effectiveness of benralizumab, mepolizumab and omalizumab in patients with SAA-NP in real-life settings. A retrospective, observational, multicenter real-life study was realized including patients with SAA-NP treated by benralizumab, mepolizumab or omalizumab for 6 months. We analysed the nasal and respiratory symptoms, the number of asthma attacks and salbutamol use/week, acute sinusitis and severe exacerbation rates, the asthma control score, the lung function parameters, the NP endoscopic score, the sinus imaging and the blood eosinophil count 6 months before and after treatment. Seventy-two patients with SAA-NP were included: 16 treated by benralizumab, 21 by mepolizumab and 35 by omalizumab. After 6 months of treatment, almost all studied parameters were improved (except sinus imaging) with a greater effect of omalizumab on the nasal pruritus (p = 0.001) and more benefits of benralizumab on exacerbations rate, asthma attacks per week and lung function (all p < 0.05). Benralizumab and mepolizumab were more effective to improve the NP endoscopic score and the blood eosinophil count (both p < 0.001). All three biological therapies showed effectiveness by improving asthma and nasal outcomes in patients with SAA-NP. Several differences have been found that should be confirmed by larger comparative studies.
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Antiasmáticos , Anticuerpos Monoclonales Humanizados , Asma , Pólipos Nasales , Humanos , Antiasmáticos/uso terapéutico , Asma/complicaciones , Asma/tratamiento farmacológico , Pólipos Nasales/complicaciones , Pólipos Nasales/tratamiento farmacológico , Omalizumab/uso terapéutico , Estudios Retrospectivos , Anticuerpos Monoclonales Humanizados/uso terapéuticoRESUMEN
INTRODUCTION: Humanized monoclonal anti-IgE antibody (omalizumab) has demonstrated efficacy in severe atopic asthma. However, few studies have assessed its efficacy in non-atopic and even less in T2-low severe asthma. The objective was to determinate the omalizumab response according to atopic status. METHODS: This retrospective, real-world study was performed in the Chest Diseases Department of Strasbourg University Hospital from January 1, 2006, to June 30, 2017. The response to omalizumab was assessed in 139 patients 4, 6, and 12 months after treatment and compared to data collected prior to omalizumab initiation. RESULTS: Forty-four patients (31.7%) had severe non-atopic asthma and 95 (68.3%) had a severe atopic asthma. In the non-atopic group, omalizumab significantly reduced the severe exacerbation rate by 44% (95% CI 18-64%, p < 0.05), 43% (CI 95% 20-60%, p < 0.05), and 54% (CI 95% 36-67%, p < 0.05), at 4, 6 and 12 months, respectively. A trend toward improvement in FEV1, asthma control and oral corticosteroid use was also observed. These results were not significantly different from those obtained in atopic asthmatics except a more effective oral corticosteroid sparing in atopic group (p < 0.05). Similar reduction of severe exacerbation rates were observed in T2-low asthma subgroup (non-atopic, non-eosinophilic). CONCLUSION: Omalizumab was effective in severe asthma, regardless of atopic status.
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Antiasmáticos , Asma , Hipersensibilidad Inmediata , Humanos , Omalizumab/uso terapéutico , Estudios Retrospectivos , Anticuerpos Monoclonales Humanizados/uso terapéutico , Corticoesteroides/uso terapéutico , Resultado del TratamientoRESUMEN
BACKGROUND: Dysphonia is a frequent comorbidity of asthma and has been suggested to be a local side effect of inhaled corticosteroids due to laryngeal candidiasis. We hypothesized that dysphonia in asthmatics was not due to laryngeal organic lesions but to laryngeal dysfunction during phonation (LDP). OBJECTIVE: We compared the frequency of LDP in female asthmatic patients treated with inhaled corticosteroids to female controls. METHODS: We compared 68 asthmatic female patients to 53 female control subjects. Pulmonary function tests were performed and the asthmatic patients classified according to the level of inhaled corticosteroids. Dysphonia was defined as a Vocal Handicap Index ≥18 or GRBAS score ≥2. All patients underwent video laryngo-strobe examination, analyzed blindly and separately by two otolaryngologists, describing mucosal changes, LDP, or Organic lesions linked to Laryngeal Dysfunction during Phonation (OLDP). RESULTS: 66.2% of the asthmatic patients exhibited dysphonia and 11.3% of controls (p < 0.001). No laryngeal candidiasis was found, only 3 patients presented laryngeal mucosa inflammation. LDP was observed in 60.3% of asthmatic patients and 18.9% of controls (p < 0.001), and no difference was found for OLDP (11.8% vs. 13.2%). No association was made between LDP, the dosage of inhaled corticosteroid, and bronchial obstruction. CONCLUSIONS: Asthmatic patients were more dysphonic than control subjects. This phenomenon was not explained by mucosal inflammation, laryngeal candidiasis or OLDP. Asthmatic patients had more LDP than controls. There was no relation between LDP, inhaled corticosteroids dosage or bronchial obstruction. These results change our view of inhaled corticosteroid side effects in female asthmatic patients.
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BACKGROUND: The dominant allergen in cat dander, Felis domesticus allergen 1 (Fel d 1), is a persistent trigger for allergic rhinitis and asthma symptoms. OBJECTIVE: We evaluated the efficacy of Fel d 1 monoclonal antibodies (REGN1908/1909) in preventing cat allergen-induced early asthmatic responses (EARs) in cat-allergic patients with mild asthma. METHODS: Patients were randomized to single-dose REGN1908/1909 600 mg (n = 29) or placebo (n = 27). The FEV1 was measured for up to 4 hours in a cat allergen environmental exposure unit up to 85 days after dosing. Assessments included between-group differences in change from baseline in FEV1 area under the curve (AUC; 0-2 hours) and incidence of EAR (FEV1 reduction ≥20%). TRIAL REGISTRATION: NCT03838731. RESULTS: Single-dose REGN1908/1909 significantly prevented reductions in FEV1 on days 8, 29, 57, and 85. Most REGN1908/1909 patients did not have an EAR by 4 hours (the last time point tested). In contrast, placebo-treated patients experienced a ≥20% mean FEV1 reduction on days 8, 29, 57, and 85 after dosing, with most experiencing an EAR within 1 hour. REGN1908/1909-treated patients tolerated 3-fold higher allergen quantities (P < .05 at all time points) versus placebo. REGN1908/1909 substantially reduced skin test reactivity to cat allergen versus placebo at all time points tested (nominal P < .001). REGN1908/1909 was generally well tolerated; no serious adverse events or deaths were reported. CONCLUSION: Single-dose REGN1908/1909 significantly prevented reductions in FEV1 in cat-allergic patients with mild asthma on cat allergen environmental exposure unit exposure at 8 days and up to 85 days after dose.
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Alérgenos , Estado de Salud , Exposición a Riesgos Ambientales/efectos adversosRESUMEN
BACKGROUND: Topical mast cell stabilizers were previously shown to treat the signs and symptoms of seasonal and perennial allergic conjunctivitis safely and effectively in active and placebo-controlled trials. However, mast cell stabilizers have not been compared to topical corticosteroids for efficacy. We tested the non-inferiority of a topical mast cell stabilizer, N-acetyl aspartyl glutamic acid (4.9%, NAAGA), compared to fluorometholone (0.1%, FM) during controlled exposures to the airborne birch pollen allergen, Bet v 1, in an environmental exposure chamber (EEC). METHODS: This randomized, cross-over, investigator-blinded study included 24 patients with a history of birch pollen allergic conjunctivitis. Patients were randomized to 5 days of treatment with NAAGA, then FM (n = 12) or FM, then NAAGA (n = 12). After each treatment, patients were exposed to a fixed airborne concentration of Bet v 1 in ALYATEC EEC. The primary endpoint was the amount of allergen required to trigger a conjunctival response (Abelson score ≥5). Groups were compared with a linear model for cross-over studies. Non-inferiority was assumed, when the lower bound of the risk ratio confidence interval (CI) was >0.5. RESULTS: At screening, the mean time-to-conjunctival response was 72.5 ± 35.9 min. NAAGA and FM extended the response time to 114.8 ± 55.0 and 116.6 ± 51.5 min respectively. The mean amounts of allergen required to trigger a conjunctival response were 1.165 ng after NAAGA and 1.193 ng after FM treatment. The risk ratio for the conjunctival response was 0.977 (95% CI: 0.812; 1.174), which indicated non-inferiority. Adverse events occurred less frequently with NAAGA (29.2%) than with FM (58.3%). CONCLUSION: In patients with allergic conjunctivitis to birch pollen, NAAGA was non-inferior to FM in exposures to airborne Bet v 1. The EEC was a good model for simulating real-life airborne allergen exposure and for demonstrating the efficacy and safety of eye drops for treating allergic conjunctivitis. TRIAL REGISTRATION: Not registered.