Background: Oak and birch pollens are strongly cross-reactive. It is unknown how robust this cross-reactivity is in patients without natural exposure to pollen of both trees. We assessed the symptom response to birch pollen in subjects with skin-prick test (SPT) results positive to oak and birch but only naturally exposed to oak by using an allergen challenge chamber. Methods: The subjects with SPT results positive to oak and birch had their serum-specific immunoglobulin E (ssIgE) to oak and birch antigens measured. Residential historical data were obtained. The subjects were exposed to birch pollen (3500 ± 700 grains/m³) in two consecutive 3-hour challenges. Symptoms were recorded at baseline and 30-minute intervals. Results: Twenty-four subjects, 12 men; ages 20-58 years, completed the study. Sixteen subjects (66.7%) responded with high Total Symptom Scores (TSS) ≥10 of a maximum 21. Twelve subjects (50%) had ssIgE values ≥0.70 kU/L to oak, 10 of whom had ssIgE values ≥0.70 kU/L to birch. These 10 subjects had a significantly higher maximum TSS than the rest. Also, 15 subjects without a previous natural exposure to birch pollen responded with TSS equivalent to the 9 subjects with previous exposure. Conclusion: Virginia live oak ssIgE levels of patients allergic to oak and birch correlated with the symptom response to birch pollen exposure, even without previous natural exposure to birch. The subjects naive to birch pollen responded to birch pollen exposure with symptoms comparable with both those with previous sustained exposure and also those who resided in endemic areas, as reported by other researchers.

Allergen exposure chambers (AECs) can be used for controlled exposure to allergenic and non-allergenic airborne particles in an enclosed environment, in order to (i) characterize the pathological features of respiratory diseases and (ii) contribute to and accelerate the clinical development of pharmacological treatments and allergen immunotherapy for allergic disease of the respiratory tract (such as allergic rhinitis, allergic rhinoconjunctivitis, and allergic asthma). In the guidelines of the European Medicines Agency for the clinical development of products for allergen immunotherapy (AIT), the role of AECs in determining primary endpoints in dose-finding Phase II trials is emphasized. Although methodologically insulated from the variability of natural pollen exposure, chamber models remain confined to supporting secondary, rather than primary, endpoints in Phase III registration trials. The need for further validation in comparison with field exposure is clearly mandated. On this basis, the European Academy of Allergy and Clinical Immunology (EAACI) initiated a Task Force in 2015 charged to gain a better understanding of how AECs can generate knowledge about respiratory allergies and can contribute to the clinical development of treatments. Researchers working with AECs worldwide were asked to provide technical information in eight sections: (i) dimensions and structure of the AEC, (ii) AEC staff, (iii) airflow, air processing, and operating conditions, (iv) particle dispersal, (v) pollen/particle counting, (vi) safety and non-contamination measures, (vii) procedures for symptom assessments, (viii) tested allergens/substances and validation procedures. On this basis, a minimal set of technical requirements for AECs applied to the field of allergology is proposed.

BACKGROUND:Allergic asthma (AA) and allergic rhinoconjunctivitis (ARC) are common comorbid environmentally triggered diseases. We hypothesized that severe AA/ARC reflects a maladaptive or unrestrained response to ubiquitous aeroallergens. METHODS:We performed provocation studies wherein six separate cohorts of persons (total n = 217) with ARC, with or without AA, were challenged once or more with fixed concentrations of seasonal or perennial aeroallergens in an aeroallergen challenge chamber (ACC). RESULTS:Aeroallergen challenges elicited fully or partially restrained vs. unrestrained evoked symptom responsiveness, corresponding to the resilient and adaptive vs. maladaptive AA/ARC phenotypes, respectively. The maladaptive phenotype was evoked more commonly during challenge with a non-endemic versus endemic seasonal aeroallergen. In an AA cohort, symptom responses evoked after house dust mite (HDM) challenges vs. recorded in the natural environment were more accurate and precise predictors of asthma severity and control, lung function (FEV1), and mechanistic correlates of maladaptation. Correlates included elevated levels of peripheral blood CD4+ and CD8+ T-cells, eosinophils, and T-cell activation, as well as gene expression proxies for ineffectual epithelial injury/repair responses. Evoked symptom severity after HDM challenge appeared to be more closely related to levels of CD4+ and CD8+ T-cells than eosinophils, neutrophils, or HDM-specific IgE. CONCLUSIONS:Provocation studies support the concept that resilience, adaptation, and maladaptation to environmental disease triggers calibrate AA/ARC severity. Despite the ubiquity of aeroallergens, in response to these disease triggers in controlled settings (ie, ACC), most atopic persons manifest the resilient or adaptive phenotype. Thus, ARC/AA disease progression may reflect the failure to preserve the resilient or adaptive phenotype. The triangulation of CD8+ T-cell activation, airway epithelial injury/repair processes and maladaptation in mediating AA disease severity needs more investigation.

BACKGROUND:Signifying the 2-compartments/1-disease paradigm, allergic rhinoconjunctivitis (ARC) and asthma (AA) are prevalent, comorbid conditions triggered by environmental factors (eg, house dust mites [HDMs]). However, despite the ubiquity of triggers, progression to severe ARC/AA is infrequent, suggesting either resilience or adaptation.OBJECTIVE:We sought to determine whether ARC/AA severity relates to maladaptive responses to disease triggers.METHODS:Adults with HDM-associated ARC were challenged repetitively with HDMs in an aeroallergen challenge chamber. Mechanistic traits associated with disease severity were identified.RESULTS:HDM challenges evoked maladaptive (persistently higher ARC symptoms), adaptive (progressive symptom reduction), and resilient (resistance to symptom induction) phenotypes. Symptom severity in the natural environment was an imprecise correlate of the phenotypes. Nasal airway traits, defined by low inflammation-effectual epithelial integrity, moderate inflammation-effectual epithelial integrity, and higher inflammation-ineffectual epithelial integrity, were hallmarks of the resilient, adaptive, and maladaptive evoked phenotypes, respectively. Highlighting a crosstalk mechanism, peripheral blood inflammatory tone calibrated these traits: ineffectual epithelial integrity associated with CD8+ T cells, whereas airway inflammation associated with both CD8+ T cells and eosinophils. Hallmark peripheral blood maladaptive traits were increased natural killer and CD8+ T cells, lower CD4+ mucosal-associated invariant T cells, and deficiencies along the TLR-IRF-IFN antiviral pathway. Maladaptive traits tracking HDM-associated ARC also contributed to AA risk and severity models.CONCLUSIONS:Repetitive challenges with HDMs revealed that maladaptation to disease triggers may underpin ARC/AA disease severity. A combinatorial therapeutic approach may involve reversal of loss-of-beneficial-function traits (ineffectual epithelial integrity, TLR-IRF-IFN deficiencies), mitigation of gain-of-adverse-function traits (inflammation), and blocking of a detrimental crosstalk between the peripheral blood and airway compartments.

Challenge of mice with ragweed pollen extract (RWPE) stimulates TLR4-mediated innate neutrophil recruitment. Adoptive transfer of neutrophils into the airways of Tlr4 KO mice reconstitutes RWPE-induced allergic airway inflammation and IL-33 secretion (PMID 26086549). Here we test the hypothesis that exposure of allergic human subjects to ragweed pollen stimulates recruitment of neutrophils that stimulate IL-33 secretion from airway epithelial cells. Ten healthy non-allergic subjects and 18 ragweed allergic responder subjects with allergic rhinitis were exposed to ragweed pollens in a pollen exposure chamber (PEC) for three hours, and allergic symptoms scores were recorded (IRB Protocol Number: 1.2016). Blood neutrophils were isolated from four healthy and four allergic subjects at baseline and at 3h after start of pollen exposure, and cocultured with human bronchial epithelial cells (HBEC) for 24 hours. IL-33 levels were measured in cell supernatants. Exposure of allergic but not healthy non-allergic subjects to ragweed pollen increased naso-ocular symptom scores in 30 mins that peaked at 3 hours, and increased the numbers of blood neutrophils. Culture of neutrophils obtained from allergic and healthy human subjects at baseline stimulated secretion of IL-33 secretion. Neutrophils obtained three hours post ragweed exposure stimulated even greater IL-33 secretion. Exposure of allergic human subjects to ragweed pollen in PEC stimulates neutrophil recruitment into the blood. Neutrophils obtained from subjects after ragweed exposure stimulates greater IL-33 secretion than those obtained at baseline. We suggest that pollen exposure stimulates neutrophil recruitment, and these neutrophils facilitate allergic inflammation by stimulating IL-33 secretion from airway epithelial cells.

Background: GSP301 is an investigational fixed-dose combination nasal spray that contains the antihistamine, olopatadine hydrochloride (HCl), and the corticosteroid, mometasone furoate. Objective: To evaluate the efficacy and safety of GSP301 in patients with seasonal allergic rhinitis (SAR). Methods: In this double-blind, randomized, parallel-group study, patients (≥12 years of age) with SAR were equally randomized to intranasal GSP301 (olopatadine 665 μg and mometasone 25 μg), olopatadine HCl (665 μg), mometasone furoate (25 μg), or placebo for 14 days of twice-daily treatment. The primary end point was the mean change from baseline in the average A.M. and P.M. 12-hour reflective Total Nasal Symptom Score (rTNSS) analyzed by using mixed-effect model repeated measures (p < 0.05 indicates statistical significance). Additional assessments included instantaneous TNSS (iTNSS), individual nasal symptoms, reflective Total Ocular Symptom Score (rTOSS) and instantaneous Total Ocular Symptom Score (iTOSS), onset of action, Physician-assessed Nasal Symptom Score (PNSS), quality of life, and adverse events (AE). Results: A total of 1180 patients were randomized. Over 14 days of treatment, GSP301 significantly improved average A.M. and P.M. rTNSS versus placebo (least squares mean difference -0.98 [95% confidence interval, -1.38 to -0.57]; p < 0.001) and versus olopatadine (p = 0.003), and approached statistical significance versus mometasone (p = 0.059). GSP301 also significantly improved average A.M. and P.M. iTNSS versus placebo and both monotherapies (p < 0.05, all). Further, GSP301 significantly improved individual nasal symptoms, overall ocular symptoms (rTOSS and iTOSS), and overall quality of life versus placebo (p < 0.01, all). Onset of action for GSP301 was observed within 15 minutes and was maintained at all subsequent time points assessed. Results for the PNSS also were significant for GSP301 versus placebo (p < 0.001). The percentages of patients with treatment-emergent AEs treated with GSP301, olopatadine, mometasone, and placebo were 12.9, 12.5, 7.1, and 9.4%, respectively. Conclusion: GSP301 was efficacious and well tolerated for the treatment of SAR symptoms compared with placebo, with a rapid onset of action of 15 minutes in patients ≥12 years of age.Clinical trial NCT02631551, www.clinicaltrials.gov.

Background: A variety of antigens have been identified as causative of hypersensitivity pneumonitis (HP), which is characterized by inflammation to the lung parenchyma that is induced by exposure. Goose and duck down (GDD) bedding is often overlooked by physicians as a potential cause, yet the use of GDD has markedly increased in recent years, paralleling an increased frequency of reports of GDD-induced HP. Objective: To determine the frequency of GDD as the causative antigen in patients with HP who use bedding that contains GDD. Methods: Patients referred with a working diagnosis of HP underwent a detailed environmental history. Those who were using GDD were asked to remove it as an avoidance procedure. Signs, symptoms, spirometry, and inflammatory markers were followed up at weekly intervals for up to 1 month to determine the effect of remediation. Results: Eighty patients with HP were seen during an 8-year period. Thirty-two patients (40%) were using GDD bedding. Of these 32 patients, 12 (37.5% of those exposed and 15% of the total HP population experienced remission (or nonprogression) of disease by simply avoiding GDD bedding. Eleven (92%) of these 12 patients were female. In patients with GDD-induced HP, lung biopsy patterns were varied. Conclusion: Approximately one-third of patients with HP, who slept with GDD, had persistent improvement or remission with simple avoidance. The higher incidence of GDD-induced HP in females may be hormonal and/or sociocultural related. Lung biopsy findings were across the spectrum of histopathologic patterns. Avoidance-challenge techniques were effective in confirming diagnoses and causation and mitigating the need for additional remediation. (C) 2019 American College of Allergy, Asthma & Immunology. Published by Elsevier Inc. All rights reserved.

Background: Controlled allergen challenge facilities (CACF), in disparate geographic regions with dissimilar engineering and base populations, have historically functioned as single, independent sites in clinical allergy trials. We aimed to demonstrate "between-unit reproducibility" to allow controlled challenge trials of participants using 2 CACFs. Objective: To compare and standardize 2 CACFs located in Kingston, Ontario, Canada, and San Antonio, Texas, by examining participant-reported symptom severity during qualifying and treatment visits and evaluating response to treatment, while using the same allergen. Methods: At 2 different CACFs, participants were enrolled in a double-blind, placebo-controlled, crossover intervention trial with cetirizine 10 mg. Different distribution devices delivered common short ragweed pollen via laminar air flow and maintained an airborne concentration of 3500 +/- 700 grains/m(3) in both facilities. A 1-hour "sham" run with no pollen release preceded a priming exposure of 3 hours and was followed 3 days later by a qualifying/treatment 5-hour exposure. At least 14 days later, another priming exposure was followed by the crossover exposure and treatment. Results: Forty-eight and 43 subjects completed the study at Kingston and San Antonio, respectively. Demographics were similar. Fewer than 10% exhibited symptoms with sham exposure. No significant differences were found between the 2 facilities in maximal total rhinoconjunctivitis symptom score, total nasal symptom score, and total ocular symptom score, nor in areas under the curve. In both facilities, no significant effects of cetirizine 10 mg over placebo were detected. Conclusion: The results were equivalent, demonstrating that the 2 CACFs can be used together in dual-center clinical trials and show the possibility of multicenter trials involving multiple CACFs. (C) 2019 American College of Allergy, Asthma & Immunology. Published by Elsevier Inc. All rights reserved.

Combining an intranasal antihistamine with an intranasal corticosteroid for the treatment of allergic rhinitis (AR) may provide improved symptom relief over monotherapy treatment. GSP301 nasal spray is a fixed-dose combination of the antihistamine olopatadine hydrochloride and the corticosteroid mometasone furoate. The efficacy and safety of GSP301 were evaluated in a large, phase 3 seasonal AR (SAR) study. In this double-blind, randomized, parallel-group study [NCT02631551], patients (≥12 years) with SAR were equally randomized to twice-daily GSP301 (olopatadine 665μg/mometasone 25μg BID), olopatadine HCl (665μg BID), mometasone furoate (25μg BID), or placebo (BID) for 14 days. The primary efficacy endpoint was the mean change from baseline in AM and PM reflective total nasal symptom scores (rTNSS), analyzed using mixed-effect model repeated measures. Adverse events (AEs) were also assessed. A total of 1,180 patients were randomized. GSP301 significantly improved rTNSS versus placebo (least squares mean difference [95% CI]: -0.98 [-1.38, -0.57], P<0.001) and versus olopatadine (-0.61 [-1.01, -0.21]; P=0.003). A clinically meaningful, numerical improvement in rTNSS that approached significance was observed with GSP301 versus mometasone (-0.39 [-0.79, 0.01], P=0.059). Compared with placebo, mometasone monotherapy significantly improved rTNSS (-0.59 [-1.00, -0.19]; P=0.004), but olopatadine monotherapy was not significant (-0.37 [-0.78, 0.04]; P=0.076). Additionally, the percentages of patients with treatment-emergent AEs were similar across treatment groups: 12.9%, 12.5%, 7.1% and 9.4% in the GSP301, olopatadine, mometasone, and placebo groups, respectively. In this study, twice-daily GSP301 treatment provided significant and clinically meaningful improvements in SAR nasal symptoms versus placebo and was well tolerated.

Repair of oxidatively-induced DNA base lesions can stimulate innate and allergic airway inflammation. Specific allergenic extracts like ragweed pollen extract and cat dander extract (CDE) induce TLR4-dependent oxidative stress and DNA damage. These studies suggest that stimulation of an innate receptor/adaptor by allergenic extracts initiates excision of a set of DNA-base lesions. The extent of DNA damage in the genome of nasal epithelial cells of human subjects has not been reported. Wild-type (WT) and Myd88KO naïve mice were intranasally challenged once with CDE, and oxidatively-induced DNA base lesions in lung genomic DNA was quantified by GC-MS/MS Genomic DNA was isolated from Rhinoprobe nasal curettes samples collected from eight human subjects with asymptomatic allergic rhinitis (AAR) and four healthy human nonallergic control subjects (NC), and long-run real-time PCR technique for DNA-damage quantification (LORD-Q) assay was performed to quantify total damage to genomic DNA in these samples. CDE challenge stimulated MyD88-dependent excision of DNA base lesions 5-OH-Cyt, FapyAde and FapyGua from the lung genome of mice and innate and allergic airway inflammation. The level of DNA damage in nasal epithelial cells was lower in AAR human subjects compared to NC human subjects. These data suggest that repair and reduction of DNA base lesions in genomic DNA is associated with increased airway inflammation, whereas low levels of DNA damage is associated with an asymptomatic state in human subjects with allergic rhinitis.

Controlled allergen challenge facilities(CACF), in disparate geographic regions with dissimilar engineering and base-populations, have historically functioned as single, independent sites in clinical allergy trials. Natural setting trials, involving multiple sites, introduce many uncontrolled variables. We aimed to demonstrate site equivalency, or “between-unit reproducibility” to allow controlled challenge trials of large numbers of participants, utilizing two CACFs, facilitating efficacy evaluations of novel interventions. At two different CACFs, participants were enrolled in a double-blind, placebo-controlled, crossover intervention trial with cetirizine. Different distribution devices delivered ragweed pollen at 3500 (±700) grains/m3 via laminar air flow at both sites. A series of Rotorod®s were utilized at site 1(S1) and the Allergenco cassette system at site 2(S2). A one hour “sham” run with no pollen release preceded a priming exposure of three hours followed 3 days later by a qualifying/treatment exposure of 5 hours. Another priming exposure at least 14 days later was followed in 3 days by the cross-over exposure and treatment. Forty-seven and 43 subjects completed the study at S1 and S2, respectively. Demographics were similar. Less than 10% exhibited symptoms with sham exposure. There were no significant differences between the two facilities in maximal total rhinoconjunctivitis symptom score, total nasal symptom score, and total ocular symptom score, nor in terms of the area under the curve for mean responses. Responses to cetirizine and placebo were statistically similar. Despite engineering differences between the two CACFs, there were equivalent results demonstrating that these facilities can be utilized with confidence for a single clinical trial.

Background: An emerging paradigm holds that resistance to the development of allergic diseases, including allergic rhinoconjunctivitis, relates to an intact epithelial/epidermal barrier during early childhood. Conceivably, the immunologic and genomic footprint of this resistance is preserved in nonatopic, nonallergic adults and is unmasked during exposure to an aeroallergen.Objective: The aim of this study was to obtain direct support of the epithelial/epidermal barrier model for allergic rhinoconjunctivitis.Methods: Twenty-three adults allergic to house dust mites (HDMs) (M+) and 15 nonsensitive, nonallergic (M-) participants completed 3-hour exposures to aerosolized HDM (Dermatophagoides pteronyssinus) powder on 4 consecutive days in an allergen challenge chamber. We analyzed: (1) peripheral blood leukocyte levels and immune responses; and (2) RNA sequencing-derived expression profiles of nasal cells, before and after HDM exposure.Results: On HDM challenge: (1) onlyM+ persons developed allergic rhinoconjunctivitis symptoms; and (2) peripheral blood leukocyte levels/responses and gene expression patterns in nasal cells were largely concordant between M+ and M- participants; gross differences in these parameters were not observed at baseline (pre-exposure). Two key differences were observed. First, peripheral blood CD4(+) and CD8(+) T-cell activation levels initially decreased in M- participants versus increased in M+ participants. Second, in M-compared with M+ participants, genes that promoted epidermal/epithelial barrier function (eg, filament- aggregating protein [filaggrin]) versus inflammation (eg, chemokines) and innate immunity (interferon) were upregulated versus muted, respectively.Conclusion: An imprint of resistance to HDM challenge in nonatopic, nonallergic adults was muted T-cell activation in the peripheral blood and inflammatory response in the nasal compartment, coupled with upregulation of genes that promote epidermal/epithelial cell barrier function.

BACKGROUND:There are few direct data concerning symptom dynamics of allergic conjunctivitis (AC) in an allergen challenge chamber (ACC).OBJECTIVE:To determine the AC dynamics on subsequent exposures to ragweed pollen (RW) in individuals with allergic rhinitis in an ACC. To determine whether consecutive exposures in an ACC have any persistent detrimental ocular physical effects.METHODS:Participants underwent 3 exposures to RW in an ACC. Ocular symptoms of itching and tearing were self-assessed. Ocular redness and lid swelling were assessed by trained ophthalmic technicians. Complete ophthalmic examinations (COEs) were performed by an ophthalmologist.RESULTS:A total of 188 of 201 participants (93%) developed an ocular redness score of 2 or more in each eye in ACC exposure 1. Reproducibility of redness occurred in approximately 70% of individuals completing ACC exposures 1 through 3. There were no significant changes between baseline COE and end of study COE. Phenotypes were identified by redness responses during and after exposure. Baseline total ocular symptom scores, at 24 hours after a priming exposure, were identified as late-phase reactions rather than enhanced sensitivity.CONCLUSION:When assessed by trained professionals, AC was present with a very high frequency in selected individuals allergic to RW monitored in an ACC. Intrasubject reproducibility of redness was consistent across 3 ACC allergen exposures. Phenotypes were identified as early-phase responses, protracted early-phase responses, dual responses, and late-phase responses.TRIAL REGISTRATION:clinicaltrials.gov Identifier: NCT02079649.

Hypersensitivity pneumonitis (HP) is an inflammatory lung disorder caused by the inhalation of an organic antigen in predisposed patients. Activation of the immune system, directed toward the antigen, leads to recruitment of inflammatory cells resulting in insult to respiratory dynamics. There are 3 temporal patterns of HP based on the history of symptoms and the course of the disease: acute, subacute, and chronic.1 Exacerbations may occur in all 3 forms depending on levels of exposure.1 Many cases can quickly be diagnosed using somewhat antiquated criteria.

The proceedings of a National Institutes of Health workshop and a meeting of an Advisory Committee of the US Food and Drug Administration,1U.S. Food and Drug Administration Center for Biologics Evaluation and Research: Allergenic Products Advisory Committee, May 12, 2011. Available at: http://www.fda.gov/downloads/AdvisoryCommittees/CommitteesMeetingMaterials/BloodVaccinesandOtherBiologics/AllergenicProductsAdvisoryCommittee/UCM258587.pdf. Accessed May 28, 2014.Google Scholar, 2Togias A. Asthma, Allergy, and Inflammation Branch, Division of Allergy, Immunology and Transplantation, NIAID/NIHEnvironmental exposure units: clinical trial design for validation. National Institute for Allergy and Infectious Diseases/National Institutes of Health, Bethesda2010: 1-12Google Scholar as well as related commentaries,3Bernstein J.A. Correlation between a pollen challenge chamber and a natural allergen exposure study design for eliciting ocular and nasal symptoms: early evidence supporting a paradigm shift in drug investigation?.J Allergy Clin Immunol. 2012; 130: 128-129Abstract Full Text Full Text PDF PubMed Scopus (16) Google Scholar, 4Devillier P. Le Gall M. Horak F. The allergen challenge chamber: a valuable tool for optimizing the clinical development of pollen immunotherapy.Allergy. 2011; 66: 163-169Crossref PubMed Scopus (48) Google Scholar highlight the utility of an allergen challenge chamber (ACC) for conducting clinical trials for allergic rhinoconjunctivitis (AR). Mitigation of factors that might confound the design, analysis, and interpretation of these trials requires a systematic comparison of symptoms present in the natural setting versus those elicited after exposure to aeroallergens in an ACC. In prior studies we conducted out-of-season challenges with 3 separate pollens in patients with seasonal allergy.5Jacobs R.L. Harper N. He W. Andrews C.P. Rather C.G. Ramirez D.A. et al.Responses to ragweed pollen in a pollen challenge chamber versus seasonal exposure identify allergic rhinoconjunctivitis endotypes.J Allergy Clin Immunol. 2012; 130: 122-127.e8Abstract Full Text Full Text PDF PubMed Scopus (50) Google Scholar, 6Jacobs R.L. Harper N. He W. Andrews C.P. Rather C.G. Ramirez D.A. et al.Effect of confounding cofactors on responses to pollens during natural season versus pollen challenge chamber exposure.J Allergy Clin Immunol. 2014; 133 (e1-7): 1340-1346Abstract Full Text Full Text PDF PubMed Scopus (25) Google Scholar Although there was high correlation in symptom scores in the natural pollination seasons and ACC, competing environmental influences (eg, mold) in the natural setting blunted the responsiveness to these pollens, whereas this confounder was not present in the ACC.5Jacobs R.L. Harper N. He W. Andrews C.P. Rather C.G. Ramirez D.A. et al.Responses to ragweed pollen in a pollen challenge chamber versus seasonal exposure identify allergic rhinoconjunctivitis endotypes.J Allergy Clin Immunol. 2012; 130: 122-127.e8Abstract Full Text Full Text PDF PubMed Scopus (50) Google Scholar, 6Jacobs R.L. Harper N. He W. Andrews C.P. Rather C.G. Ramirez D.A. et al.Effect of confounding cofactors on responses to pollens during natural season versus pollen challenge chamber exposure.J Allergy Clin Immunol. 2014; 133 (e1-7): 1340-1346Abstract Full Text Full Text PDF PubMed Scopus (25) Google Scholar However, most patients with allergy are polysensitized to outdoor (eg, pollens) and indoor (eg, house dust mite [HDM]) aeroallergens. HDM exposure is common, associated with perennial allergy, and a significant risk factor for AR and asthma. Here we compared the symptom dynamics in the natural setting versus the ACC in HDM-sensitive (M+) and nonsensitive (M−) participants meeting the inclusion/exclusion criteria shown in Table E1 in this article's Online Repository at www.jacionline.org. M− subjects lacked both a history of AR and skin prick test (SPT) wheal reactivity (≥5 mm) to 17 allergens, including HDM (see Table E2 in this article's Online Repository at www.jacionline.org). The study comprised 4 study phases: a 4-day run-in phase followed by 2 ACC exposure phases (ACC-I and ACC-II) with an intervening 38-day observation phase (Fig 1, A). This design allowed for evaluation of the reproducibility of symptom responses and factors that could potentially confound clinical trials in the ACC, including mediators of nocebo effects,7Bingel U. Avoiding nocebo effects to optimize treatment outcome.JAMA. 2014; 312: 693-694Crossref PubMed Scopus (141) Google Scholar as discussed in the Methods section in this article's Online Repository at www.jacionline.org. The study was conducted in the early fall, when only weed pollens were detected in San Antonio, Texas (Fig 1, A and B).6Jacobs R.L. Harper N. He W. Andrews C.P. Rather C.G. Ramirez D.A. et al.Effect of confounding cofactors on responses to pollens during natural season versus pollen challenge chamber exposure.J Allergy Clin Immunol. 2014; 133 (e1-7): 1340-1346Abstract Full Text Full Text PDF PubMed Scopus (25) Google Scholar To mitigate this confounding factor, we selected M+ participants with negative SPT responses for weed pollens (see Table E2). All participants were allergy drug free throughout the study (see Table E3 in this article's Online Repository at www.jacionline.org). Each ACC phase comprised exposure for 3 hours on 4 consecutive days to a purified mite body powder of Dermatophagoides pteronyssinus (Fig 1, A and B, and see the Methods section in this article's Online Repository). The end point we targeted was an increase in instantaneous total symptom scores (iTSSs) of at least 6 units in 50% of participants from baseline levels. To achieve this goal, the ACC was calibrated to deliver 70 to 110 ng/m3 HDM Der p 1 antigen, as measured by means of ELISA (see Table E4 and the Methods section in this article's Online Repository at www.jacionline.org). iTSSs in the ACC and reflective total symptom scores (rTSSs) in the natural setting were recorded by using a 5-point Likert scale (see Table E5 in this article's Online Repository at www.jacionline.org). Of the 40 participants meeting inclusion criteria, 35 (21 M+ and 14 M− participants) completed all 4 study phases, and of these, 13 M+ participants and 1 M− participant had detectable (≥0.35 kU/L) serum specific IgE (ssIgE) to D pteronyssinus. This dichotomy between SPT reactivity but undetectable ssIgE has been reported for many allergens (see the Discussion section in this article's Online Repository at www.jacionline.org).8de Vos G. Skin testing versus serum-specific IgE testing: which is better for diagnosing aeroallergen sensitization and predicting clinical allergy?.Curr Allergy Asthma Rep. 2014; 14: 430Crossref PubMed Scopus (50) Google Scholar There were no differences in the key demographic characteristics between M+ and M− participants (see Table E6 in this article's Online Repository at www.jacionline.org). Five participants withdrew from the study for nonmedical reasons. M− participants had minimal symptoms in the ACC (mean iTSS, <1; Fig 1, B). In contrast, M+ participants experienced a mean increase of 3 units in the iTSS within 30 minutes of HDM challenge, and iTSSs reached a plateau after approximately 120 minutes (Fig 1, B). There was a high degree of concordance in symptom responses in M+ participants in the ACC recorded by using the Likert and visual analog scales (see Fig E1 in this article's Online Repository at www.jacionline.org). Eleven episodes of bronchospasm occurred in 5 M+ participants, a rate consistent with prior findings.9Horak F. Toth J. Marks B. Stubner U.P. Berger U.E. Jager S. et al.Efficacy and safety relative to placebo of an oral formulation of cetirizine and sustained-release pseudoephedrine in the management of nasal congestion.Allergy. 1998; 53: 849-856Crossref PubMed Scopus (43) Google Scholar These participants exhibited slightly higher total symptom scores (TSSs; see Fig E2 in this article's Online Repository at www.jacionline.org), had greater than 15% improvement in FEV1.0 after treatment with nebulized albuterol, and returned to the ACC without additional exacerbations (see the Discussion section in this article's Online Repository). These findings suggest that M+ participants with mild intermittent asthma can be safely evaluated within ACCs. The concordance in symptom responses during and between ACC-I and ACC-II was high (Fig 1, C, and see Table E7 in this article's Online Repository at www.jacionline.org). In contrast, the correlations between rTSSs recorded in the run-in versus observation phases or between rTSSs versus iTSSs were much lower (see Fig E3 in this article's Online Repository at www.jacionline.org). During ACC-I and ACC-II, an increase in iTSSs of 6 or greater from baseline (pre-exposure) was experienced in greater than 55% of participants (Fig 1, D). While less than 10% of participants had iTSSs of 15 or greater at baseline, 67% and 57% of M+ participants achieved iTSSs of 15 or greater in ACC-I and ACC-II, respectively (Fig 1, E). Substantial data indicate that ssIgE levels to allergens might serve as biomarkers for symptom severity.10Ciprandi G. Tosca M.A. Silvestri M. The practical role of serum allergen-specific IgE as potential biomarker for predicting responder to allergen immunotherapy.Expert Rev Clin Immunol. 2014; 10: 321-324Crossref PubMed Scopus (11) Google Scholar Accordingly, TSSs were greater in M+ participants with a detectable ssIgE level for D pteronyssinus in the ACC (Fig 2, A and B). The failure to detect such an association in the natural setting (Fig 2, A and B) might relate to variable HDM levels measured in dust from mattresses in the participants' homes (see Fig E4 and the Methods section in this article's Online Repository at www.jacionline.org). Pollen SPT reactivity (P+) stratified TSSs, with M+P+ participants having higher rTSSs and iTSSs when compared with those of M+P− participants (Fig 2, C). Levels of T-cell activation were greater in M+P+ participants compared with those seen in M+P− participants before and during ACCs (Fig 2, D, and see Fig E5 and the Methods section in this article's Online Repository at www.jacionline.org). Notably, T-cell activation has been associated with symptom responses during allergy.11Majori M. Piccoli M.L. Melej R. Pileggi V. Pesci A. Lymphocyte activation markers in peripheral blood before and after natural exposure to allergen in asthmatic patients.Respiration. 1997; 64: 45-49Crossref PubMed Scopus (7) Google Scholar Thus exposure to pollens in the months preceding the ACC exposures might have rendered M+P+ participants constitutively "primed," serving as a basis for the higher T-cell activation and symptoms in the natural and ACC settings (Fig 2, C and D). In the ACC phases the effects of pollen sensitization and ssIgE status were additive, with M+IgE+P+ participants manifesting maximal responsiveness after HDM exposure (Fig 2, E). The trigger for the constitutive priming could be winter and spring tree pollens because all M+P+ participants were reactive based on SPT reactivity to tree pollens (see Table E2). Moreover, the extended tree pollination season, which terminated a few months before the start of the ACC exposures, is typically associated with intense symptoms.6Jacobs R.L. Harper N. He W. Andrews C.P. Rather C.G. Ramirez D.A. et al.Effect of confounding cofactors on responses to pollens during natural season versus pollen challenge chamber exposure.J Allergy Clin Immunol. 2014; 133 (e1-7): 1340-1346Abstract Full Text Full Text PDF PubMed Scopus (25) Google Scholar At the 2 transition points from the natural settings to the ACC (run-in → ACC-I and observation phase → ACC-II), there was a decrease in TSSs (Fig 1, Fig 2, A). This decrease was greater in those with more symptoms (ie, higher in M+P+ participants than in M+P− participants [Fig 2, F] and higher in M+IgE+ participants than in M+IgE− participants [data not shown]). This decrease might relate to (1) differences in how TSSs were recorded in the natural versus ACC settings (reflective vs instantaneous scoring, respectively); (2) learned responses secondary to increased emphasis/education by research staff in the ACC on how to accurately record TSSs; and (3) the controlled environment in the ACC (see the Discussion in this article's Online Repository). Inspection of the overall TSS trajectory indicated that after initiation of ACC exposures, there was a downward shift in the TSS (Fig 1, B). The baseline (pre-ACC) iTSS recorded before commencing challenge 1 was higher than the baseline iTSS recorded before challenges 2 and 3, and the baseline iTSS before challenges 4 through 8 were similar (Fig 1, B). Furthermore, the rTSS in the observation phase was lower than the rTSS in the run-in phase (Fig 1, B). This downward shift in baseline iTSS would give the mistaken impression that responsiveness was greater in challenges 2 and 3 and lower thereafter, when in fact the responsiveness in exposures 1 and 4 through 8 was similar (Fig 2, G). These downward shifts in TSSs did not differ by pollen SPT or ssIgE status (data not shown), and we surmise this might relate to a combination of factors: learned responses (secondary to education in the ACC) and partial clinical tolerance akin to what has been observed after repetitive exposure to allergens, including HDM (see the Discussion section in this article's Online Repository).12Woodfolk J.A. High-dose allergen exposure leads to tolerance.Clin Rev Allergy Immunol. 2005; 28: 43-58Crossref PubMed Google Scholar, 13Liu L.Y. Swenson C.A. Kelly E.A. Kita H. Jarjour N.N. Busse W.W. Comparison of the effects of repetitive low-dose and single-dose antigen challenge on airway inflammation.J Allergy Clin Immunol. 2003; 111: 818-825Abstract Full Text Full Text PDF PubMed Scopus (17) Google Scholar In this study exposure to HDM concentrations used in the ACC was associated with reliable and reproducible elicitation of symptoms. SPT reactivity to pollen, which was associated with increased inflammatory status, and ssIgE levels to HDM were biological markers that correlated with symptom responses in the ACC. These 2 biomarkers stratified M+ participants as higher versus lower responders in the ACC, whereas this stratification is obscured in the natural settings. Therefore we suggest that out-of-pollination season challenges with HDM in the ACC might help mitigate the confounding of factors present in the natural setting: variable or low exposure to HDM, lack of association of ssIgE levels with rTSSs, and effects of competing environmental influences in a primed polysensitized subject. We also suggest that the other factors that could potentially confound clinical trials in an ACC (and natural setting) are nocebo7Bingel U. Avoiding nocebo effects to optimize treatment outcome.JAMA. 2014; 312: 693-694Crossref PubMed Scopus (141) Google Scholar and placebo14Enck P. Bingel U. Schedlowski M. Rief W. The placebo response in medicine: minimize, maximize or personalize?.Nat Rev Drug Discov. 2013; 12: 191-204Crossref PubMed Scopus (476) Google Scholar effects (expectations, learning process, and participant-physician communication). Confounding could occur by (1) misattribution of positive therapy effects to decrease symptom scores related to more precise symptom scoring (because of learned behavior) and/or partial clinical tolerance (because of repetitive exposure) and (2) imbalance in the proportion of high versus low responders in the treatment versus placebo arms. An example that highlights the potential for this imbalance is the observation that the effectiveness of anti-IgE therapy for asthma differed by the overall sensitization status of the trial participants.15Busse W.W. Morgan W.J. Gergen P.J. Mitchell H.E. Gern J.E. Liu A.H. et al.Randomized trial of omalizumab (anti-IgE) for asthma in inner-city children.N Engl J Med. 2011; 364: 1005-1015Crossref PubMed Scopus (732) Google Scholar Therapies might be more effective in patients with greater responsiveness to allergen exposure, a trait that can be readily identified in an ACC. Thus we surmise that mindfulness of the abovementioned confounders and use of an ACC might together facilitate detection of differences in the effects of placebo versus therapy in clinical trials, especially in exploratory studies with novel therapeutic agents when both the participant numbers and therapy effect sizes might be modest. Download .docx (.23 MB) Help with docx files Online Repository Data Download .pdf (.39 MB) Help with pdf files Fig E1 Download .pdf (.16 MB) Help with pdf files Fig E2 Download .pdf (.4 MB) Help with pdf files Fig E3 Download .pdf (.37 MB) Help with pdf files Fig E4 Download .pdf (.68 MB) Help with pdf files Fig E5

BACKGROUND:Modifiers of symptom severity in patients with allergic rhinoconjunctivitis (AR) are imprecisely characterized. The hygiene hypothesis implicates childhood microbial exposure as a protective factor. Cockroach sensitization (C+) might be a proxy for microbial exposure. OBJECTIVE:We sought to determine whether C+ assayed by means of skin prick tests influenced AR symptom severity in controlled and natural settings. METHODS:Total symptom scores (TSSs) were recorded by 21 participants with house dust mite allergy (M+) in the natural setting and during repeated exposures of 3 hours per day to house dust mite allergen in an allergen challenge chamber (ACC). In M+ participants the peripheral blood and nasal cells were assayed for T-cell activation and transcriptomic profiles (by using RNA sequencing), respectively. Participants allergic to mountain cedar (n = 21), oak (n = 34), and ragweed (n = 23) recorded TSSs during separate out-of-season exposures to these pollens (any pollen sensitization [P+]) in the ACC; a subset recorded TSSs in the pollination seasons. RESULTS:The hierarchy of TSSs (highest to lowest) among M+ participants tracked the following skin prick test sensitization statuses: M+P+C- > M+P+C+ > M+P-C- > M+P-C+. In nasal cells and peripheral blood the immune/inflammatory responses were rapidly resolved in M+P+C+ compared with M+P+C- participants. Among those allergic to pollen, C+ was associated with a lower TSS during pollen challenges and the pollination season. After aggregated analysis of all 4 ACC studies, C+ status was associated with a 2.8-fold greater likelihood of a lower TSS compared with C- status (odds ratio, 2.78; 95% CI, 1.18-6.67; P = .02). CONCLUSIONS:C+ status is associated with mitigation of AR symptom severity in adults with AR.

RationaleAttempt to demonstrate nasal fluticasone propionate 200 μg daily (FP200QD) for 14 days is superior to placebo in relieving ocular symptoms.MethodsThis was a randomized, double-blind, parallel group, multicenter study comparing FP200QD with placebo in patients (n = 626, age 12 to 79 years) with seasonal allergic rhinitis. The primary endpoint was change from baseline in patient-rated reflective Total Ocular Symptoms Score (rTOSS). Secondary endpoints included change from baseline in the am and pm rTOSS, end-of-treatment assessment of response, and daily activities impact. Primary analysis was analysis of covariance (linear fixed-effects mode).ResultsFP200QD was more efficacious in ocular symptoms relief than placebo utilizing primary endpoint (difference = -0.36, p = 0.0024). It improved am and pm rTOSS vs placebo (AM: difference = -0.33, p = 0.0057; PM: difference = -0.41, p = 0.0009). More patients on FP200QD reported overall improvement at end of treatment (177 vs 146 in placebo, p = 0.0118). FP200QD significantly improved daily activities as measured by MiniRQLQ (p<0.0001) and was well tolerated.ConclusionsThe study results support that FP200QD relieves ocular symptoms in AR. RationaleAttempt to demonstrate nasal fluticasone propionate 200 μg daily (FP200QD) for 14 days is superior to placebo in relieving ocular symptoms. Attempt to demonstrate nasal fluticasone propionate 200 μg daily (FP200QD) for 14 days is superior to placebo in relieving ocular symptoms. MethodsThis was a randomized, double-blind, parallel group, multicenter study comparing FP200QD with placebo in patients (n = 626, age 12 to 79 years) with seasonal allergic rhinitis. The primary endpoint was change from baseline in patient-rated reflective Total Ocular Symptoms Score (rTOSS). Secondary endpoints included change from baseline in the am and pm rTOSS, end-of-treatment assessment of response, and daily activities impact. Primary analysis was analysis of covariance (linear fixed-effects mode). This was a randomized, double-blind, parallel group, multicenter study comparing FP200QD with placebo in patients (n = 626, age 12 to 79 years) with seasonal allergic rhinitis. The primary endpoint was change from baseline in patient-rated reflective Total Ocular Symptoms Score (rTOSS). Secondary endpoints included change from baseline in the am and pm rTOSS, end-of-treatment assessment of response, and daily activities impact. Primary analysis was analysis of covariance (linear fixed-effects mode). ResultsFP200QD was more efficacious in ocular symptoms relief than placebo utilizing primary endpoint (difference = -0.36, p = 0.0024). It improved am and pm rTOSS vs placebo (AM: difference = -0.33, p = 0.0057; PM: difference = -0.41, p = 0.0009). More patients on FP200QD reported overall improvement at end of treatment (177 vs 146 in placebo, p = 0.0118). FP200QD significantly improved daily activities as measured by MiniRQLQ (p<0.0001) and was well tolerated. FP200QD was more efficacious in ocular symptoms relief than placebo utilizing primary endpoint (difference = -0.36, p = 0.0024). It improved am and pm rTOSS vs placebo (AM: difference = -0.33, p = 0.0057; PM: difference = -0.41, p = 0.0009). More patients on FP200QD reported overall improvement at end of treatment (177 vs 146 in placebo, p = 0.0118). FP200QD significantly improved daily activities as measured by MiniRQLQ (p<0.0001) and was well tolerated. ConclusionsThe study results support that FP200QD relieves ocular symptoms in AR. The study results support that FP200QD relieves ocular symptoms in AR.

Background: Allergic rhinitis (AR) is an inflammatory condition of the nasal mucosa characterized by symptoms of nasal discharge, itching, sneezing, and congestion. Ocular symptoms are commonly associated with AR and include itching or burning, tearing or watering, and redness. Intranasal corticosteroids are a mainstay of treatment, and their effect on nasal symptoms is well described.Objective: To demonstrate that a 14-day course of 200 mg/d of nasal fluticasone propionate is superior to placebo in relieving ocular symptoms associated with AR.Methods: This was a randomized, double-blind, parallel group, multicenter study comparing 200 mg/d of fluticasone propionate with placebo in patients with seasonal allergic rhinitis. The primary end point was mean change from baseline in patient-rated reflective total ocular symptom score (rTOSS). Key secondary end points included mean change from baseline in the morning and evening rTOSS, end-of-treatment assessment of response, and effect on activities of daily living. The primary analysis was performed using analysis of covariance with a linear fixed-effects model.Results: Fluticasone was statistically significantly more efficacious in reducing the ocular symptoms of AR than placebo. The least squares mean difference in the change from baseline of rTOSS was -0.36 (P=.002). A statistically significant difference in mean change from baseline was observed in favor of fluticasone for morning and evening rTOSS. Significantly more patients taking fluticasone achieved an overall response compared with placebo. Fluticasone had a significantly greater effect on daily living activities and was well tolerated.Conclusion: This study supports the efficacy of fluticasone in treating ocular symptoms associated with AR. Trial Registration: clinicaltrials.govIdentifier: NCT01817790. (C) 2015 American College of Allergy, Asthma & Immunology. Published by Elsevier Inc. All rights reserved.

Background: Beclomethasone dipropionate (BDP) nasal aerosol (non-aqueous) is approved for management of seasonal and perennial allergic rhinitis (PAR) in adolescents and adults.Objective: To evaluate the efficacy and safety of BDP nasal aerosol at 80 mg/day in children with PAR.Methods: This 12-week, phase 3, double-blinded, placebo-controlled, parallel-group study randomized 547 children (4-11 years old) with PAR to once-daily BDP nasal aerosol at 80 mg/day or placebo. The primary end point was change from baseline in average morning and evening reflective total nasal symptom score (rTNSS) during the first 6 weeks of treatment in patients 6 to 11 years old. Changes from baseline in average morning and evening instantaneous TNSS (iTNSS) in children 6 to 11 years old and average rTNSS and iTNSS in children 4 to 11 years old were assessed during the first 6 weeks of treatment.Results: Improvements were significantly greater with BDP nasal aerosol than with placebo during the first 6 weeks of treatment in children 6 to 11 years old in average morning and evening rTNSS and iTNSS (mean treatment difference -0.66 [ P = .002] and -0.58 [ P = .004], respectively). Improvements in average morning and evening rTNSS and iTNSS also were significantly greater in patients 4 to 11 years receiving BDP nasal aerosol than with placebo during the first 6 weeks of treatment (P - .002 and P - .004, respectively). Similar improvements were seen during 12 weeks of treatment. The safety profile of BDP nasal aerosol was comparable to that of placebo.Conclusion: The BDP nasal aerosol at 80 mg/day in children 4 to 11 years old was well tolerated and effective in controlling nasal symptoms of PAR. (C) 2015 American College of Allergy, Asthma & Immunology. Published by Elsevier Inc.