Phase 3 Trial of Epicutaneous Immunotherapy in Toddlers with Peanut Allergy

BACKGROUND

No approved treatment for peanut allergy exists for children younger than 4 years of age, and the efficacy and safety of epicutaneous immunotherapy with a peanut patch in toddlers with peanut allergy are unknown.

METHODS

We conducted this phase 3, multicenter, double-blind, randomized, placebo-controlled trial involving children 1 to 3 years of age with peanut allergy confirmed by a double-blind, placebo-controlled food challenge. Patients who had an eliciting dose (the dose necessary to elicit an allergic reaction) of 300 mg or less of peanut protein were assigned in a 2:1 ratio to receive epicutaneous immunotherapy delivered by means of a peanut patch (intervention group) or to receive placebo administered daily for 12 months. The primary end point was a treatment response as measured by the eliciting dose of peanut protein at 12 months. Safety was assessed according to the occurrence of adverse events during the use of the peanut patch or placebo.

RESULTS

Of the 362 patients who underwent randomization, 84.8% completed the trial. The primary efficacy end point result was observed in 67.0% of children in the intervention group as compared with 33.5% of those in the placebo group (risk difference, 33.4 percentage points; 95% confidence interval, 22.4 to 44.5; P<0.001). Adverse events that occurred during the use of the intervention or placebo, irrespective of relatedness, were observed in 100% of the patients in the intervention group and 99.2% in the placebo group. Serious adverse events occurred in 8.6% of the patients in the intervention group and 2.5% of those in the placebo group; anaphylaxis occurred in 7.8% and 3.4%, respectively. Serious treatment-related adverse events occurred in 0.4% of patients in the intervention group and none in the placebo group. Treatment-related anaphylaxis occurred in 1.6% in the intervention group and none in the placebo group.

CONCLUSIONS

In this trial involving children 1 to 3 years of age with peanut allergy, epicutaneous immunotherapy for 12 months was superior to placebo in desensitizing children to peanuts and increasing the peanut dose that triggered allergic symptoms. (Funded by DBV Technologies; EPITOPE ClinicalTrials.gov number, NCT03211247.).

Efficacy and safety of peanut epicutaneous immunotherapy in patients with atopic comorbidities

Background

Co-occurring atopic conditions are common in children with peanut allergy. As such, it is important to examine the safety and efficacy of epicutaneous immunotherapy with Viaskin Peanut 250 μg patch (VP250) in peanut-allergic children with these conditions.

Objective

We sought to compare efficacy and safety of VP250 versus placebo in peanut-allergic children with/without ongoing atopic conditions at baseline, including asthma, atopic dermatitis/eczema, or concomitant food allergy.

Methods

A subgroup analysis of peanut-allergic children aged 4 to 11 years enrolled in PEPITES (12 months) and REALISE (6 months) randomized, placebo-controlled, phase 3 trials was conducted. The efficacy outcome measure was the difference in prespecified responder rate between placebo and VP250 groups at month 12 based on eliciting dose of peanut protein using double-blind, placebo-controlled food challenge in PEPITES. Safety profiles were evaluated by baseline concomitant disease subgroup in all randomized subjects who received 1 or more dose of the study drug in PEPITES and REALISE pooled data.

Results

Responder rates were significantly (P < .05, all comparisons) greater with VP250 compared with placebo treatment regardless of whether subjects had other atopic conditions. Safety and tolerability profiles were generally similar across subgroups, with no new safety concerns detected. A trend for both higher responder rates and rates of local reactions was observed in subjects with baseline atopic dermatitis versus those without. In subjects with concomitant food allergy at baseline, higher rates of treatment-emergent adverse events, but not study discontinuations or overall rates of anaphylaxis, were observed.

Conclusions

The results support the safety and efficacy of VP250 for treating peanut-allergic children with or without concomitant atopic conditions.

Associations between outdoor air pollutants and non-viral asthma exacerbations and airway inflammatory responses in children and adolescents living in urban areas in the USA: a retrospective secondary analysis

BACKGROUND

Asthma prevalence and severity have markedly increased with urbanisation, and children in low-income urban centres have among the greatest asthma morbidity. Outdoor air pollution has been associated with adverse respiratory effects in children with asthma. However, the mechanisms by which air pollution exposure exacerbates asthma, and how these mechanisms compare with exacerbations induced by respiratory viruses, are poorly understood. We aimed to investigate the associations between regional air pollutant concentrations, respiratory illnesses, lung function, and upper airway transcriptional signatures in children with asthma, with particular focus on asthma exacerbations occurring in the absence of respiratory virus.

METHODS

We performed a retrospective analysis of data from the MUPPITS1 cohort and validated our findings in the ICATA cohort. The MUPPITS1 cohort recruited 208 children aged 6-17 years living in urban areas across nine US cities with exacerbation-prone asthma between Oct 7, 2015, and Oct 18, 2016, and monitored them during reported respiratory illnesses. The last MUPPITS1 study visit occurred on Jan 6, 2017. The ICATA cohort recruited 419 participants aged 6-20 years with persistent allergic asthma living in urban sites across eight US cities between Oct 23, 2006, and March 25, 2008, and the last study visit occurred on Dec 30, 2009. We included participants from the MUPPITS1 cohort who reported a respiratory illness at some point during the follow-up and participants from the ICATA cohort who had nasal samples collected during respiratory illness or at a scheduled visit. We used air quality index values and air pollutant concentrations for PM2·5, PM10, O3, NO2, SO2, CO, and Pb from the US Environmental Protection Agency spanning the years of both cohorts, and matched values and concentrations to each illness for each participant. We investigated the associations between regional air pollutant concentrations and respiratory illnesses and asthma exacerbations, pulmonary function, and upper airway transcriptional signatures by use of a combination of generalised additive models, case crossover analyses, and generalised linear mixed-effects models.

FINDINGS

Of the 208 participants from the MUPPITS1 cohort and 419 participants from the ICATA cohort, 168 participants in the MUPPITS1 cohort (98 male participants and 70 female participants) and 189 participants in the ICATA cohort (115 male participants and 74 female participants) were included in our analysis. We identified that increased air quality index values, driven predominantly by increased PM2·5 and O3 concentrations, were significantly associated with asthma exacerbations and decreases in pulmonary function that occurred in the absence of a provoking viral infection. Moreover, individual pollutants were significantly associated with altered gene expression in coordinated inflammatory pathways, including PM2·5 with increased epithelial induction of tissue kallikreins, mucus hypersecretion, and barrier functions and O3 with increased type-2 inflammation.

INTERPRETATION

Our findings suggest that air pollution is an important independent risk factor for asthma exacerbations in children living in urban areas and is potentially linked to exacerbations through specific inflammatory pathways in the airway. Further investigation of these potential mechanistic pathways could inform asthma prevention and management approaches.

FUNDING

National Institutes of Health, National Institute of Allergy and Infectious Diseases.

Mepolizumab for urban children with exacerbation-prone eosinophilic asthma in the USA (MUPPITS-2): a randomised, double-blind, placebo-controlled, parallel-group trial

BACKGROUND

Black and Hispanic children living in urban environments in the USA have an excess burden of morbidity and mortality from asthma. Therapies directed at the eosinophilic phenotype reduce asthma exacerbations in adults, but few data are available in children and diverse populations. Furthermore, the molecular mechanisms that underlie exacerbations either being prevented by, or persisting despite, immune-based therapies are not well understood. We aimed to determine whether mepolizumab, added to guidelines-based care, reduced the number of asthma exacerbations during a 52-week period compared with guidelines-based care alone.

METHODS

This is a randomised, double-blind, placebo-controlled, parallel-group trial done at nine urban medical centres in the USA. Children and adolescents aged 6-17 years, who lived in socioeconomically disadvantaged neighbourhoods and had exacerbation-prone asthma (defined as ≥two exacerbations in the previous year) and blood eosinophils of at least 150 cells per μL were randomly assigned 1:1 to mepolizumab (6-11 years: 40 mg; 12-17 years: 100 mg) or placebo injections once every 4 weeks, plus guideline-based care, for 52 weeks. Randomisation was done using a validated automated system. Participants, investigators, and the research staff who collected outcome measures remained masked to group assignments. The primary outcome was the number of asthma exacerbations that were treated with systemic corticosteroids during 52 weeks in the intention-to-treat population. The mechanisms of treatment response were assessed by study investigators using nasal transcriptomic modular analysis. Safety was assessed in the intention-to-treat population. This trial is registered with ClinicalTrials.gov, NCT03292588.

FINDINGS

Between Nov 1, 2017, and Mar 12, 2020, we recruited 585 children and adolescents. We screened 390 individuals, of whom 335 met the inclusion criteria and were enrolled. 290 met the randomisation criteria, were randomly assigned to mepolizumab (n=146) or placebo (n=144), and were included in the intention-to-treat analysis. 248 completed the study. The mean number of asthma exacerbations within the 52-week study period was 0·96 (95% CI 0·78-1·17) with mepolizumab and 1·30 (1·08-1·57) with placebo (rate ratio 0·73; 0·56-0·96; p=0·027). Treatment-emergent adverse events occurred in 42 (29%) of 146 participants in the mepolizumab group versus 16 (11%) of 144 participants in the placebo group. No deaths were attributed to mepolizumab.

INTERPRETATION

Phenotype-directed therapy with mepolizumab in urban children with exacerbation-prone eosinophilic asthma reduced the number of exacerbations.

FUNDING

US National Institute of Allergy and Infectious Diseases and GlaxoSmithKline.

Safety of Epicutaneous Immunotherapy in Peanut-Allergic Children: REALISE Randomized Clinical Trial Results

BACKGROUND

Treatment options for peanut allergy are limited. In previous clinical trials, epicutaneous immunotherapy with a patch containing 250-μg peanut protein (Viaskin Peanut 250 μg [VP250]) was well tolerated and statistically superior to placebo in desensitizing peanut-allergic children.

OBJECTIVE

To examine the safety of VP250 in children, using a study design approximating potential real-world use.

METHODS

REAL LIfe Use and Safety of EPIT (REALISE) is a phase 3 multicenter study consisting of a 6-month, randomized, double-blind, placebo-controlled period followed by open-label active treatment. Children aged 4 to 11 years with physician diagnosis of peanut allergy received daily treatment with placebo (6 months) or VP250 (up to 36 months). Data from the 6-month, randomized, controlled phase of REALISE are reported.

RESULTS

Three hundred ninety-three children were randomized 3:1 to receive VP250 (n = 294) or placebo (n = 99) for 6 months; 284 (72.3%) children had a history of peanut anaphylaxis. According to parent diary, all participants receiving VP250 and 83.8% receiving placebo reported at least 1 episode of local skin reaction, with frequency decreasing over time. Only 4 participants (1.4%) receiving VP250 discontinued because of adverse events (AEs). Epinephrine was administered for allergic reactions attributed to VP250 in 7 children (2.4%), of whom 5 remained in the study; none involved severe anaphylaxis. Overall, AE rates were similar among participants with and without a history of peanut anaphylaxis.

CONCLUSIONS

In a study designed to mirror real-world use, VP250 was observed to be well tolerated in peanut-allergic children, consistent with previous phase 2b and 3 studies.

Seasonal airway microbiome and transcriptome interactions promote childhood asthma exacerbations

BACKGROUND

Seasonal variation in respiratory illnesses and exacerbations in pediatric populations with asthma is well described, though whether upper airway microbes play season-specific roles in these events is unknown.

OBJECTIVE

We hypothesized that nasal microbiota composition is seasonally dynamic and that discrete microbe-host interactions modify risk of asthma exacerbation in a season-specific manner.

METHODS

Repeated nasal samples from children with exacerbation-prone asthma collected during periods of respiratory health (baseline; n = 181 samples) or first captured respiratory illness (n = 97) across all seasons, underwent bacterial (16S ribosomal RNA gene) and fungal (internal transcribed spacer region 2) biomarker sequencing. Virus detection was performed by multiplex PCR. Paired nasal transcriptome data were examined for seasonal dynamics and integrative analyses.

RESULTS

Upper airway bacterial and fungal microbiota and rhinovirus detection exhibited significant seasonal dynamics. In seasonally adjusted analysis, variation in both baseline and respiratory illness microbiota related to subsequent exacerbation. Specifically, in the fall, when respiratory illness and exacerbation events were most frequent, several Moraxella and Haemophilus members were enriched both in virus-positive respiratory illnesses and those that progressed to exacerbations. The abundance of 2 discrete bacterial networks, characteristically comprising either Streptococcus or Staphylococcus, exhibited opposing interactions with an exacerbation-associated SMAD3 nasal epithelial transcriptional module to significantly increase the odds of subsequent exacerbation (odds ratio = 14.7, 95% confidence interval = 1.50-144, P = .02; odds ratio = 39.17, 95% confidence interval = 2.44-626, P = .008, respectively).

CONCLUSIONS

Upper airway microbiomes covary with season and with seasonal trends in respiratory illnesses and asthma exacerbations. Seasonally adjusted analyses reveal specific bacteria-host interactions that significantly increase risk of asthma exacerbation in these children.

Real world use of peanut component testing among children in the Chicago metropolitan area

Background: Peanut component tests (PCT) have become important in the evaluation of peanut allergy. There remains a paucity of research across the United States in investigating the utility of PCT in clinical practice in conjunction with current standards of care. Objective: The primary aims were to evaluate the performance and sensitization patterns of PCT in clinical practice when first available at our institution. Methods: We performed a retrospective chart review of 184 children with PCT and oral food challenge (OFC) results between 2012 and 2017. Simple logistic regression models assessed the associations between PCT and OFC outcomes. Receiver operator characteristic curves were constructed, and a predicted probability curve was derived for Ara h2. Results: The median (interquartile range [IQR]) age at OFC was 4 years (2-7 years), and 111 patients (60%) were boys. Ara h 2 was the most commonly sensitized PCT. Sixty-one patients (33%) reacted at OFC. Ara h 2 specific immunoglobulin E (sIgE) ≥ 0.35 kU_A/L was associated with increased odds of reacting at OFC (odds ratio 5.91 95% confidence interval, 2.93-11.89; p < 0.001); however, 19 patients (37%) positive for Ara h 2 did not react. Ara h 2 sIgE of 0.49 kU_A/L and 4.58 kU_A/L were associated with 50% and 90% probability, respectively, of reacting at OFC. Among those sensitized only to Ara h 8 or 9 (n = 21), 86% had no reaction. There was no statistically significant association with polysensitization to Ara h 1, 2, and 3, and peanut OFC outcome. Conclusion: Although the Ara h 2 sIgE value was associated with clinical reactivity, a significant proportion of the patients sensitized to Ara h 2 tolerated peanut. OFC remains an important tool in the evaluation of peanut allergy.

Association of mold levels in urban children's homes with difficult-to-control asthma

BACKGROUND

Mold sensitization and exposure are associated with asthma severity, but the specific species that contribute to difficult-to-control (DTC) asthma are unknown.

OBJECTIVE

We sought to determine the association between overall and specific mold levels in the homes of urban children and DTC asthma.

METHODS

The Asthma Phenotypes in the Inner-City study recruited participants, aged 6 to 17 years, from 8 US cities and classified each participant as having either DTC asthma or easy-to-control (ETC) asthma on the basis of treatment step level. Dust samples had been collected in each participant's home (n = 485), and any dust remaining (n = 265 samples), after other analyses, was frozen at -20^oC. The dust samples (n = 265) were analyzed using quantitative PCR to determine the concentrations of the 36 molds in the Environmental Relative Moldiness Index. Logistic regression was performed to discriminate specific mold content of dust from homes of children with DTC versus ETC asthma.

RESULTS

Frozen-dust samples were available from 54% of homes of children with DTC (139 of 253) and ETC asthma (126 of 232). Only the average concentration of the mold Mucor was significantly (P < .001) greater in homes of children with DTC asthma. In homes with window air-conditioning units, the Mucor concentration contributed about a 22% increase (1.6 odds ratio; 95% CI, 1.2-2.2) in the ability to discriminate between cases of DTC and ETC asthma.

CONCLUSIONS

Mucor levels in the homes of urban youth were a predictor of DTC asthma, and these higher Mucor levels were more likely in homes with a window air-conditioner.

Interactive Inpatient Asthma Education: A Randomized Controlled Trial

BACKGROUND AND OBJECTIVES

Inpatient asthma education interventions provide benefit compared with usual care, but evaluation of the most effective educational model is needed. We compared the impact of interactive versus didactic inpatient pediatric asthma education on subsequent emergency department (ED) visits and hospitalizations.

METHODS

Children (aged 2‒16) with asthma admitted to a tertiary care children's hospital with an asthma exacerbation between October 2016 and June 2017 were randomly assigned to interactive or didactic (control) asthma education. The primary outcome was asthma ED visits at 6 and 12 months; secondary outcomes included hospitalizations (6 and 12 months), inhaler technique, asthma knowledge, symptoms, quality of life, and parental management skills at baseline, discharge, and/or 12 months.

RESULTS

One hundred forty participants (69 interactive, 71 control) completed the study. There were no differences in ED visits at 6 or 12 months. Compared to controls, the interactive group had fewer hospitalizations (10.1% vs 22.5%; P = .04) at 6 months. Inhaler technique in the interactive group improved at discharge (mean change 4.07 [95% confidence interval (CI): 3.21-4.94]) and remained increased at 12 months (P = .03). Patient-reported asthma symptoms and quality of life were similar in both groups at baseline (19.9 vs 20.62, best possible score 8) and significantly improved in the interactive group at 12 months (least square mean change, 3.52 vs -1.75; P < .01).

CONCLUSIONS

There were no differences in ED visits; however, the interactive education reduced asthma hospitalizations over a 6-month period. These findings demonstrate that educational delivery methods can play a role in improving clinical outcomes for asthma.

Pharmacogenetic studies of long-acting beta agonist and inhaled corticosteroid responsiveness in randomised controlled trials of individuals of African descent with asthma

BACKGROUND

Pharmacogenetic studies in asthma cohorts, primarily made up of White people of European descent, have identified loci associated with response to inhaled beta agonists and corticosteroids (ICSs). Differences exist in how individuals from different ancestral backgrounds respond to long-acting beta agonist (LABA) and ICSs. Therefore, we sought to understand the pharmacogenetic mechanisms regulating therapeutic responsiveness in individuals of African descent.

METHODS

We did ancestry-based pharmacogenetic studies of children (aged 5-11 years) and adolescents and adults (aged 12-69 years) from the Best African Response to Drug (BARD) trials, in which participants with asthma uncontrolled with low-dose ICS (fluticasone propionate 50 μg in children, 100 μg in adolescents and adults) received different step-up combination therapies. The hierarchal composite outcome of pairwise superior responsiveness in BARD was based on asthma exacerbations, a 31-day difference in annualised asthma-control days, or a 5% difference in percentage predicted FEV₁. We did whole-genome admixture mapping of 15 159 ancestral segments within 312 independent regions, stratified by the two age groups. The two co-primary outcome comparisons were the step up from low-dose ICS to the quintuple dose of ICS (5 × ICS: 250 μg twice daily in children and 500 μg twice daily in adolescents and adults) versus double dose (2-2·5 × ICS: 100 μg twice daily in children, 250 μg twice daily in adolescents and adults), and 5 × ICS versus 100 μg fluticasone plus a LABA (salmeterol 50 μg twice daily). We used a genome-wide significance threshold of p<1·6 × 10^-4, and tested for replication using independent cohorts of individuals of African descent with asthma.

FINDINGS

We included 249 unrelated children and 267 unrelated adolescents and adults in the BARD pharmacogenetic analysis. In children, we identified a significant admixture mapping peak for superior responsiveness to 5 × ICS versus 100 μg fluticasone plus salmeterol on chromosome 12 (odds ratio [OR_{local African}] 3·95, 95% CI 2·02-7·72, p=6·1 × 10^-5) fine mapped to a locus adjacent to RNFT2 and NOS1 (rs73399224, OR_{allele dose} 0·17, 95% CI 0·07-0·42, p=8·4 × 10^-5). In adolescents and adults, we identified a peak for superior responsiveness to 5 × ICS versus 2·5 × ICS on chromosome 22 (OR_{local African} 3·35, 1·98-5·67, p=6·8 × 10^-6) containing a locus adjacent to TPST2 (rs5752429, OR_{allele dose} 0·21, 0·09-0·52, p=5·7 × 10^-4). We replicated rs5752429 and nominally replicated rs73399224 in independent African American cohorts.

INTERPRETATION

BARD is the first genome-wide pharmacogenetic study of LABA and ICS response in clinical trials of individuals of African descent to detect and replicate genome-wide significant loci. Admixture mapping of the composite BARD trial outcome enabled the identification of novel pharmacogenetic variation accounting for differential therapeutic responses in people of African descent with asthma.

FUNDING

National Institutes of Health, National Heart, Lung, and Blood Institute.

High-resolution epitope mapping by AllerScan reveals relationships between IgE and IgG repertoires during peanut oral immunotherapy

Peanut allergy can result in life-threatening reactions and is a major public health concern. Oral immunotherapy (OIT) induces desensitization to food allergens through administration of increasing amounts of allergen. To dissect peanut-specific immunoglobulin E (IgE) and IgG responses in subjects undergoing OIT, we have developed AllerScan, a method that leverages phage-display and next-generation sequencing to identify the epitope targets of peanut-specific antibodies. We observe a striking diversification and boosting of the peanut-specific IgG repertoire after OIT and a reduction in pre-existing IgE levels against individual epitopes. High-resolution epitope mapping reveals shared recognition of public epitopes in Ara h 1, 2, 3, and 7. In individual subjects, OIT-induced IgG specificities overlap extensively with IgE and exhibit strikingly similar antibody footprints, suggesting related clonal lineages or convergent evolution of peanut-specific IgE and IgG B cells. Individual differences in epitope recognition identified via AllerScan could inform safer and more effective personalized immunotherapy.

Exploration of parent-reported food allergy symptoms via breastmilk exposures and likelihood to develop tolerance

BACKGROUND

Knowledge is limited about the relationship between clinical reactivity to foods through breastfeeding and long-term food allergy outcomes. We explored parent-perceived symptoms of food allergy via breastfeeding and the association with future tolerance.

METHODS

Subjects identified from the Chicago Food Allergy Study (2005-2011) were categorized by parent-reported reactions to maternally ingested foods via breastfeeding (50/898 peanut-allergic, 69/620 egg-allergic, and 153/589 milk-allergic). The primary outcome was tolerance [passed oral food challenge (OFC) or consumption of previously implicated food]. Secondary outcomes included severe reactions (anaphylaxis and/or cardiovascular/respiratory symptoms) and additional concomitant food allergies. Univariate chi-square analyses were performed to assess for association between variables, followed by logistic regression models.

RESULTS

Of the 50 subjects with parent-reported peanut-associated symptoms with breastfeeding, none gained tolerance. There were no significant associations between parent-reported breastfeeding symptoms and development of tolerance for egg and milk (egg: OR 0.46, 95% CI 0.21-1.01, p = 0.053; milk: OR 1.13, 95% CI 0.70-1.81, p = 0.614). All egg-allergic subjects with parent-perceived symptoms while breastfeeding also reported multiple food allergies (n = 69), but milk- and peanut-allergic subjects were not more likely to have multiple allergies (milk: OR 1.89, 95% CI 0.88-4.02, p = 0.10; peanut: OR 2.36, 95% CI 0.72-7.76, p = 0.16). There were no significant associations between parent-reported breastfeeding symptoms and subsequent reaction severity.

CONCLUSIONS

A significant proportion of parents perceive symptoms of food allergy attributable to indirect breastfeeding exposures. Our exploratory analysis suggests that infants with parent-perceived clinical reactivity to peanut via breastmilk may be less likely to gain tolerance. Infants with parent-reported reactivity to egg via breastmilk exposure were more likely to report multiple food allergies. Further rigorous prospective studies are needed to clarify the true prevalence of IgE-mediated food allergy symptoms attributable to indirect breastfeeding exposures and the association with development of tolerance.

Heterogeneity of magnitude, allergen immunodominance, and cytokine polarization of cockroach allergen-specific T cell responses in allergic sensitized children

BACKGROUND

Characterization of allergic responses to cockroach (CR), a common aeroallergen associated with asthma, has focused mainly on IgE reactivity, but little is known about T cell responses, particularly in children. We conducted a functional evaluation of CR allergen-specific T cell reactivity in a cohort of CR allergic children with asthma.

METHODS

Peripheral blood mononuclear cells (PBMCs) were obtained from 71 children, with mild-to-moderate asthma who were enrolled in a CR immunotherapy (IT) clinical trial, prior to treatment initiation. PBMC were stimulated with peptide pools derived from 11 CR allergens, and CD4+ T cell responses assessed by intracellular cytokine staining.

RESULTS

Highly heterogeneous responses in T cell reactivity were observed among participants, both in terms of the magnitude of cytokine response and allergen immunodominance. Reactivity against Bla g 9 and Bla g 5 was most frequent. The phenotype of the T cell response was dominated by IL-4 production and a Th2 polarized profile in 54.9% of participants, but IFNγ production and Th1 polarization was observed in 25.3% of the participants. The numbers of regulatory CD4+ T cells were also highly variable and the magnitude of effector responses and Th2 polarization were positively correlated with serum IgE levels specific to a clinical CR extract.

CONCLUSIONS

Our results demonstrate that in children with mild-to-moderate asthma, CR-specific T cell responses display a wide range of magnitude, allergen dominance, and polarization. These results will enable examination of whether any of the variables measured are affected by IT and/or are predictive of clinical outcomes.

African American Children Are More Likely to Be Allergic to Shellfish and Finfish: Findings from FORWARD, a Multisite Cohort Study

BACKGROUND

Despite major differences in health profiles and rates of health care utilization between African American and White children with food allergy (FA), the detailed phenotypic variables that can potentially impact these outcomes have not been thoroughly studied.

OBJECTIVE

We aimed to characterize phenotypic differences such as allergies to different foods and allergic comorbidities between African American and White children with FA enrolled in the Food Allergy Outcomes Related to White and African American Racial Differences study.

METHODS

Our active, prospective, multicenter cohort study is currently enrolling African American and White children aged 0 to 12 years diagnosed with FA and followed by allergy/immunology clinics at 4 urban tertiary centers in the United States. To evaluate associations between race and phenotypic variables, we used multivariable logistic regression, adjusting for important demographic and confounding factors, as well as potential household clustering.

RESULTS

As of May 2020, there were 239 African Americans and 425 Whites with complete intake information enrolled in the study. In comparison with Whites, we found that African Americans had significantly higher adjusted odds of allergy to finfish (odds ratio [OR]: 2.54, P < .01) and shellfish (OR: 3.10, P < .001). African Americans also had higher adjusted odds of asthma than Whites (asthma prevalence of 60.5% in African Americans and 27.2% in Whites; OR: 2.70, P < .001). In addition, shellfish allergy was associated with asthma, after controlling for race.

CONCLUSION

Among a diverse cohort of children with physician-diagnosed FA, we observed that African American children had higher odds of allergy to shellfish and finfish, and higher rates of asthma. Interestingly, having asthma was independently associated with allergy to shellfish, after controlling for race.

Inducible expression quantitative trait locus analysis of the MUC5AC gene in asthma in urban populations of children

BACKGROUND

Mucus plugging can worsen asthma control, lead to reduced lung function and fatal exacerbations. MUC5AC is the secretory mucin implicated in mucus plugging, and MUC5AC gene expression has been associated with development of airway obstruction and asthma exacerbations in urban children with asthma. However, the genetic determinants of MUC5AC expression are not established.

OBJECTIVES

This study sought to assess single-nucleotide polymorphisms (SNPs) that influence MUC5AC expression and relate to pulmonary functions in childhood asthma.

METHODS

This study used RNA-sequencing data from upper airway samples and performed cis-expression quantitative trait loci (eQTL) and allele-specific expression analyses in 2 cohorts of predominantly Black and Hispanic urban children, a high asthma-risk birth cohort, and an exacerbation-prone asthma cohort. Inducible MUC5AC eQTLs were further investigated during incipient asthma exacerbations. Significant eQTLs SNPs were tested for associations with lung function measurements and their functional consequences were investigated in DNA regulatory databases.

RESULTS

Two independent groups of SNPs in the MUC5AC gene that were significantly associated with MUC5AC expression were identified. Moreover, these SNPs showed stronger eQTL associations with MUC5AC expression during asthma exacerbations, which is consistent with inducible expression. SNPs in 1 group also showed significant association with decreased pulmonary functions. These SNPs included multiple EGR1 transcription factor binding sites, suggesting a mechanism of effect.

CONCLUSIONS

These findings demonstrate the applicability of organ-specific RNA-sequencing data to determine genetic factors contributing to a key disease pathway. Specifically, they suggest important genetic variations that may underlie propensity to mucus plugging in asthma and could be important in targeted asthma phenotyping and disease management strategies.

AAAAI Work Group Report: Trends in Oral Food Challenge Practices Among Allergists in the United States

The oral food challenge (OFC) is the criterion standard for diagnosing food allergy, but prior studies indicate many allergists may not be using OFCs for various reasons. To better understand current OFC trends, practices, and barriers, the American Academy of Allergy Asthma and Immunology (AAAAI) Adverse Reactions to Foods Committee subcommittee updated a 19-item survey (previously administered in 2009) and sent it to AAAAI and American College of Allergy, Asthma, and Immunology (ACAAI) membership. There were a total of 546 respondents who represented approximately a 10% response rate. Among the 546 respondents, compared with 2009, significantly more providers offer OFCs (95% vs 84.5%), offer >10 OFCs per month (17% vs 5.6%), obtain informed consent (82.2% vs 53.6%), and performed OFCs in fellowship (71% vs 45%) (all P < .001). Fellowship OFC training was limited, with 56% performing <10 OFCs in fellowship and 29% performing none. Although 94% see patients <12 months of age, 35.5% do not offer OFCs for early peanut introduction. Although 79% dedicate a supervising medical provider (MD, NP, PA) and 86% have a written OFC protocol, only 60% had a standardized reaction treatment protocol and 56% prepared emergency medications before OFC. Compared with 2009, there was significant worsening of perceived barriers to performing OFCs, including time (65.6% vs 55%), space (55.3% vs 27.1%), staffing (59.6% vs 44.3%), experience (16.9% vs 11.5%), and hospital proximity (10.9% vs 7.9%), though reimbursement as a barrier improved (45.9% vs 53.7%) (all P < .01). Compared with 2009, although more providers offer OFCs, multiple perceived barriers to performing OFCs have worsened. Hesitancy to challenge infants and emergency preparedness issues are emerging potential concerns.

Coconut allergy: Characteristics of reactions and diagnostic predictors in a pediatric tertiary care center

BACKGROUND

Little is known on the clinical manifestations of coconut allergy. Our knowledge to date is mainly based on case reports.

OBJECTIVE

To characterize the allergic reactions to coconut and suggest diagnostic cutoffs for specific immunoglobulin E (sIgE) and skin prick testing (SPT) to predict clinically reactive coconut allergy.

METHODS

Methods include retrospective chart review at an urban tertiary care center of patients with positive testing result for coconut. Probability curves were computed by logistic regression for SPT and coconut sIgE.

RESULTS

Of 275 records reviewed, 69 patients reported coconut reactions and 206 were sensitized only or nonallergic. The reactions occurred with breastfeeding (n = 2), contact (n = 10), or oral ingestion (n = 57). Approximately 50% of oral ingestion reactions were associated with mild/moderate anaphylaxis. Clinical reactivity vs sensitization was more common in topical coconut users (2-fold) (P = .02). Although not statistically significant, there was a trend toward more coconut allergy vs sensitization in Asian and African American patients. The probability of allergy with positive SPT result was approximately 50% and with sIgE was approximately 60%. At an SPT of 9 mm wheal or sIgE of 58 kU of allergen/L, there is a 95% probability of reaction. Cosensitization with tree nuts, legumes, and seeds was common. Macadamia nut had the strongest correlation with coconut (r = 0.81, P < .001, n = 101).

CONCLUSION

Although the rate of reactivity to coconut in sensitized individuals is low, half of the reactions from consumption met the criteria for anaphylaxis. Clinicians should be aware of the spectrum of reactions and diagnostic use of sIgE and SPT.

Preventing asthma in high risk kids (PARK) with omalizumab: Design, rationale, methods, lessons learned and adaptation

Asthma remains one of the most important challenges to pediatric public health in the US. A large majority of children with persistent and chronic asthma demonstrate aeroallergen sensitization, which remains a pivotal risk factor associated with the development of persistent, progressive asthma throughout life. In individuals with a tendency toward Type 2 inflammation, sensitization and exposure to high concentrations of offending allergens is associated with increased risk for development of, and impairment from, asthma. The cascade of biological responses to allergens is primarily mediated through IgE antibodies and their production is further stimulated by IgE responses to antigen exposure. In addition, circulating IgE impairs innate anti-viral immune responses. The latter effect could magnify the effects of another early life exposure associated with increased risk of the development of asthma - viral infections. Omalizumab binds to circulating IgE and thus ablates antigen signaling through IgE-related mechanisms. Further, it has been shown restore IFN-α response to rhinovirus and to reduce asthma exacerbations during the viral season. We therefore hypothesized that early blockade of IgE and IgE mediated responses with omalizumab would prevent the development and reduce the severity of asthma in those at high risk for developing asthma. Herein, we describe a double-blind, placebo-controlled trial of omalizumab in 2-3 year old children at high risk for development of asthma to prevent the development and reduce the severity of asthma. We describe the rationale, methods, and lessons learned in implementing this potentially transformative trial aimed at prevention of asthma.

Continuous and Daily Oral Immunotherapy for Peanut Allergy: Results from a 2-Year Open-Label Follow-On Study

BACKGROUND

The randomized, controlled PALISADE trial demonstrated the benefit of daily oral immunotherapy with Peanut (Arachis Hypogaea) allergen powder-dnfp (PTAH, formerly AR101) in peanut-allergic children and adolescents.

OBJECTIVE

ARC004, the open-label follow-on study to PALISADE, used 5 dosing cohorts to explore PTAH treatment beyond 1 year and alternative dosing regimens in peanut-allergic individuals.

METHODS

Active arm (PTAH-continuing) PALISADE participants who tolerated 300-mg peanut protein at the exit double-blind placebo-controlled food challenge and placebo arm (PTAH-naive) participants could enter ARC004. PTAH-continuing participants were assigned to receive daily (cohorts 1 and 3A) or non-daily (cohorts 2, 3B, and 3C) dosing regimens; PTAH-naive participants were built up to 300 mg/d PTAH, followed by maintenance dosing. At study completion, participants underwent an exit double-blind placebo-controlled food challenge with doses up to 2000 mg peanut protein. Data were assessed using descriptive statistics.

RESULTS

Overall, 358 (87.5%) eligible participants (4-17 years) entered ARC004 (PTAH-continuing, n = 256; PTAH-naive, n = 102). Among PTAH-continuing participants, exposure-adjusted adverse event rates were 12.94 to 17.54/participant-year and 25.95 to 42.49/participant-year in daily and non-daily dosing cohorts, respectively; most participants (83%) experienced mild or moderate adverse events. Daily dosing cohorts appeared to have higher desensitization rates than non-daily dosing cohorts. Of all PTAH-continuing cohorts, cohort 3A had the longest daily dosing duration and the highest desensitization rates. Changes in immune markers with PTAH continuation demonstrated ongoing immunomodulation. Outcomes in PTAH-naive participants mirrored those of the PALISADE active arm.

CONCLUSIONS

Continued daily PTAH treatment beyond 1 year showed sustained safety and efficacy. Ongoing immunomodulation was observed during the second year of treatment.

Food allergy-related bullying and associated peer dynamics among Black and White children in the FORWARD study

BACKGROUND

The experiences of Black children with food allergy (FA) are not well characterized, particularly with respect to bullying victimization and other psychosocial outcomes.

OBJECTIVE

To evaluate bullying experiences of Black and White children with FA, including associations with peer relationships, anxiety, and school policies.

METHODS

Surveys were administered to parents of 252 children with physician-diagnosed FA enrolled in the multisite FORWARD cohort. The surveys assessed demographics, atopic disease, bullying victimization, and school FA management practices and policies. Descriptive statistics of bullying by race were compared by χ² tests. Multiple logistic regression analyses adjusting for race, age, parental education, household income, child sex, and multi-FA compared adjusted probabilities of bullying victimization by school policies.

RESULTS

Nearly 20% of school-aged children were bullied for FA with no substantial racial differences overall, though for children ages 11 years and up, White children reported higher rates of bullying. However, Black children experienced non-FA-related bullying twice as frequently as White children (38.6% vs 17.7%; P = .002). Most of the caregivers (85.7%) who intervened in their child's bullying reported that it was helpful. Among parents, 17.3% reported that they were teased or bullied owing to their child's FA. More than half of the respondents (54.8%) reported that some allergens are banned from their child's school, most typically peanut. In schools banning peanuts, FA-related bullying was less frequently reported by all students who have food allergy.

CONCLUSION

Bullying owing to FA is common, and caregivers, medical professionals, and school administrators can help reduce bullying by screening for bullying and supporting and educating school policies.

Long-term, open-label extension study of the efficacy and safety of epicutaneous immunotherapy for peanut allergy in children: PEOPLE 3-year results

BACKGROUND

The PEPITES (Peanut EPIT Efficacy and Safety) trial, a 12-month randomized controlled study of children with peanut allergy and 4 to 11 years old, previously reported the safety and efficacy of epicutaneous immunotherapy (EPIT) for peanut allergy (250 μg, daily epicutaneous peanut protein; DBV712 250 μg).

OBJECTIVE

We sought to assess interim safety and efficacy of an additional 2 years of EPIT from the ongoing (5-year treatment) PEOPLE (PEPITES Open-Label Extension) study.

METHODS

Subjects who completed PEPITES were offered enrollment in PEOPLE. Following an additional 2 years of daily DBV712 250 μg, subjects who had received DBV712 250 μg in PEPITES underwent month-36 double-blind, placebo-controlled food challenge with an optional month-38 sustained unresponsiveness assessment.

RESULTS

Of 213 eligible subjects who had received DBV712 250 μg in PEPITES, 198 (93%) entered PEOPLE, of whom 141 (71%) had assessable double-blind, placebo-controlled food challenge at month 36. At month 36, 51.8% of subjects (73 of 141) reached an eliciting dose of ≥1000 mg, compared with 40.4% (57 of 141) at month 12; 75.9% (107 of 141) demonstrated increased eliciting dose compared with baseline; and 13.5% (19 of 141) tolerated the full double-blind, placebo-controlled food challenge of 5444 mg. Median cumulative reactive dose increased from 144 to 944 mg. Eighteen subjects underwent an optional sustained unresponsiveness assessment; 14 of those (77.8%) maintained an eliciting dose of ≥1000 mg at month 38. Local patch-site skin reactions were common but decreased over time. There was no treatment-related epinephrine use in years 2 or 3. Compliance was high (96.9%), and withdrawals due to treatment-related adverse events were low (1%).

CONCLUSIONS

These results demonstrate that daily EPIT treatment for peanut allergy beyond 1 year leads to continued response from a well-tolerated, simple-to-use regimen.

Heterogeneity of Mild to Moderate Persistent Asthma in Children: Confirmation by Latent Class Analysis and Association with 1-Year Outcomes

BACKGROUND

Compared with adults, phenotypic characterization of children with asthma is still limited and it remains difficult to predict which children with asthma are at highest risk for poor outcomes.

OBJECTIVE

To identify latent classes in a large population of treatment-adherent children with mild to moderate asthma enrolled in clinical trials and determine whether latent class assignment predicts future lung function abnormalities and exacerbation rate.

METHODS

Latent class analysis was performed on 2593 children with mild to moderate asthma aged 5 18 years, with 19 variables encompassing demographic characteristics, medical history, symptoms, lung function, allergic sensitization, and type 2 inflammation. Outcomes included lung function and the annualized exacerbation rate at 12 months of follow-up.

RESULTS

Five latent classes were identified with differing demographic features, asthma control, sensitization, type 2 inflammatory markers, and lung function. Exacerbation rates were 1.30 ± 0.12 for class 1 (multiple sensitization with partially reversible airflow limitation), 0.90 ± 0.05 for class 2 (multiple sensitization with reversible airflow limitation), 0.87 ± 0.08 for class 3 (lesser sensitization with reversible airflow limitation), 0.87 ± 0.05 for class 4 (multiple sensitization with normal lung function), and 0.71 ± 0.06 for class 5 (lesser sensitization with normal lung function). Lung function abnormalities persisted in class 1 at 12 months.

CONCLUSIONS

Children with mild to moderate asthma are a heterogeneous group. Allergic sensitization and lung function may be particularly useful in identifying children at the greatest risk for future exacerbation. Additional studies are needed to determine whether latent classes correspond to meaningful phenotypes for the purpose of personalized treatment.

Food allergy: Diagnosis and treatment

Immunoglobulin E-mediated food reactions usually develop within minutes of food ingestion. Although most reactions are not life-threatening, fatalities do occur. Risk factors for fatal food-induced anaphylaxis include the presence of asthma (a risk factor for anaphylaxis in general), failure to use epinephrine autoinjectors promptly, a history of severe reactions, known food allergy, denial of symptoms, and adolescent and young adult age. The most commonly implicated foods are cow's milk, egg, peanut, soy, tree nuts, fish, shellfish, and wheat. Peanut, tree nuts, and seafood are the most common food allergens in adults, whereas cow's milk, peanut, egg, soy, and wheat are more common in children. The major food allergens are glycoproteins, which are generally water soluble and stable to the effects of heat, proteases, and acids. Recent studies showed that natural tolerance can be acquired at a later age than previously thought, even during adolescence. Allergies to peanut, tree nuts, and seafood are frequently life-long. Patients and their caregivers should be taught when and how to administer injectable epinephrine. In terms of primary prevention, there is evidence that early introduction, followed by ongoing regular consumption of peanut has a protective effect on the development of peanut allergy.

Hereditary and acquired angioedema

Hereditary angioedema (HAE) is an autosomal dominant disorder defined by a deficiency of functional C1 esterase inhibitor (C1-INH). Acquired angioedema is due to either consumption (type 1) or inactivation (type 2) of CI-INH. Both HAE and acquired angioedema can be life-threatening. Of the three types of HAE, type 1 is most common, occurring in approximately 85% of patients and characterized by decreased production of C1-INH, which results in reduced functional activity to 5-40% of normal. Type 2 occurs in 15% of cases; C1-INH is detectable in normal or elevated quantities but is dysfunctional. Also, HAE with normal CI-INH (previously called type 3 HAE) is rare and characterized by normal complement studies. Specific genetic mutations have been linked to factor XII, angiopoietin-1, and plasminogen gene. Patients with unknown mutations are classified as unknown. The screening test for types 1 and 2 is complement component C4, which is low to absent at times of angioedema and during quiescent periods. A useful test to differentiate HAE from acquired angioedema is C1q protein, which is normal in HAE and low in acquired angioedema. The management of HAE has been transformed with the advent of disease-specific therapies. On-demand therapy options include plasma and recombinant C1-INH for intravenous infusion; ecallantide, an inhibitor of kallikrein; and icatibant, a bradykinin β₂ receptor antagonist, both administered subcutaneously. For long-term prophylaxis, intravenous or subcutaneous C1-INH enzyme replacement and lanadelumab, a monoclonal antibody against kallikrein that is administered subcutaneously, are effective agents.

Step-Up Therapy in Black Children and Adults with Poorly Controlled Asthma

BACKGROUND

Morbidity from asthma is disproportionately higher among black patients than among white patients, and black patients constitute the minority of participants in trials informing treatment. Data indicate that patients with inadequately controlled asthma benefit more from addition of a long-acting beta-agonist (LABA) than from increased glucocorticoids; however, these data may not be informative for treatment in black patients.

METHODS

We conducted two prospective, randomized, double-blind trials: one involving children and the other involving adolescents and adults. In both trials, the patients had at least one grandparent who identified as black and had asthma that was inadequately controlled with low-dose inhaled glucocorticoids. We compared combinations of therapy, which included the addition of a LABA (salmeterol) to an inhaled glucocorticoid (fluticasone propionate), a step-up to double to quintuple the dose of fluticasone, or both. The treatments were compared with the use of a composite measure that evaluated asthma exacerbations, asthma-control days, and lung function; data were stratified according to genotypic African ancestry.

RESULTS

When quintupling the dose of fluticasone (to 250 μg twice a day) was compared with adding salmeterol (50 μg twice a day) and doubling the fluticasone (to 100 μg twice a day), a superior response occurred in 46% of the children with quintupling the fluticasone and in 46% of the children with doubling the fluticasone and adding salmeterol (P = 0.99). In contrast, more adolescents and adults had a superior response to added salmeterol than to an increase in fluticasone (salmeterol-low-dose fluticasone vs. medium-dose fluticasone, 49% vs. 28% [P = 0.003]; salmeterol-medium-dose fluticasone vs. high-dose fluticasone, 49% vs. 31% [P = 0.02]). Neither the degree of African ancestry nor baseline biomarkers predicted a superior response to specific treatments. The increased dose of inhaled glucocorticoids was associated with a decrease in the ratio of urinary cortisol to creatinine in children younger than 8 years of age.

CONCLUSIONS

In contrast to black adolescents and adults, almost half the black children with poorly controlled asthma had a superior response to an increase in the dose of an inhaled glucocorticoid and almost half had a superior response to the addition of a LABA. (Funded by the National Heart, Lung, and Blood Institute; BARD ClinicalTrials.gov number, NCT01967173.).

Mometasone or Tiotropium in Mild Asthma with a Low Sputum Eosinophil Level

BACKGROUND

In many patients with mild, persistent asthma, the percentage of eosinophils in sputum is less than 2% (low eosinophil level). The appropriate treatment for these patients is unknown.

METHODS

In this 42-week, double-blind, crossover trial, we assigned 295 patients who were at least 12 years of age and who had mild, persistent asthma to receive mometasone (an inhaled glucocorticoid), tiotropium (a long-acting muscarinic antagonist), or placebo. The patients were categorized according to the sputum eosinophil level (<2% or ≥2%). The primary outcome was the response to mometasone as compared with placebo and to tiotropium as compared with placebo among patients with a low sputum eosinophil level who had a prespecified differential response to one of the trial agents. The response was determined according to a hierarchical composite outcome that incorporated treatment failure, asthma control days, and the forced expiratory volume in 1 second; a two-sided P value of less than 0.025 denoted statistical significance. A secondary outcome was a comparison of results in patients with a high sputum eosinophil level and those with a low level.

RESULTS

A total of 73% of the patients had a low eosinophil level; of these patients, 59% had a differential response to a trial agent. However, there was no significant difference in the response to mometasone or tiotropium, as compared with placebo. Among the patients with a low eosinophil level who had a differential treatment response, 57% (95% confidence interval [CI], 48 to 66) had a better response to mometasone, and 43% (95% CI, 34 to 52) had a better response to placebo (P = 0.14). In contrast 60% (95% CI, 51 to 68) had a better response to tiotropium, whereas 40% (95% CI, 32 to 49) had a better response to placebo (P = 0.029). Among patients with a high eosinophil level, the response to mometasone was significantly better than the response to placebo (74% vs. 26%) but the response to tiotropium was not (57% vs. 43%).

CONCLUSIONS

The majority of patients with mild, persistent asthma had a low sputum eosinophil level and had no significant difference in their response to either mometasone or tiotropium as compared with placebo. These data provide equipoise for a clinically directive trial to compare an inhaled glucocorticoid with other treatments in patients with a low eosinophil level. (Funded by the National Heart, Lung, and Blood Institute; SIENA ClinicalTrials.gov number, NCT02066298.).

Transcriptome networks identify mechanisms of viral and nonviral asthma exacerbations in children

Respiratory infections are common precursors to asthma exacerbations in children, but molecular immune responses that determine whether and how an infection causes an exacerbation are poorly understood. By using systems-scale network analysis, we identify repertoires of cellular transcriptional pathways that lead to and underlie distinct patterns of asthma exacerbation. Specifically, in both virus-associated and nonviral exacerbations, we demonstrate a set of core exacerbation modules, among which epithelial-associated SMAD3 signaling is upregulated and lymphocyte response pathways are downregulated early in exacerbation, followed by later upregulation of effector pathways including epidermal growth factor receptor signaling, extracellular matrix production, mucus hypersecretion, and eosinophil activation. We show an additional set of multiple inflammatory cell pathways involved in virus-associated exacerbations, in contrast to squamous cell pathways associated with nonviral exacerbations. Our work introduces an in vivo molecular platform to investigate, in a clinical setting, both the mechanisms of disease pathogenesis and therapeutic targets to modify exacerbations.

Effect of Epicutaneous Immunotherapy vs Placebo on Reaction to Peanut Protein Ingestion Among Children With Peanut Allergy: The PEPITES Randomized Clinical Trial

IMPORTANCE

There are currently no approved treatments for peanut allergy.

OBJECTIVE

To assess the efficacy and adverse events of epicutaneous immunotherapy with a peanut patch among peanut-allergic children.

DESIGN, SETTING, AND PARTICIPANTS

Phase 3, randomized, double-blind, placebo-controlled trial conducted at 31 sites in 5 countries between January 8, 2016, and August 18, 2017. Participants included peanut-allergic children (aged 4-11 years [n = 356] without a history of a severe anaphylactic reaction) developing objective symptoms during a double-blind, placebo-controlled food challenge at an eliciting dose of 300 mg or less of peanut protein.

INTERVENTIONS

Daily treatment with peanut patch containing either 250 μg of peanut protein (n = 238) or placebo (n = 118) for 12 months.

MAIN OUTCOMES AND MEASURES

The primary outcome was the percentage difference in responders between the peanut patch and placebo patch based on eliciting dose (highest dose at which objective signs/symptoms of an immediate hypersensitivity reaction developed) determined by food challenges at baseline and month 12. Participants with baseline eliciting dose of 10 mg or less were responders if the posttreatment eliciting dose was 300 mg or more; participants with baseline eliciting dose greater than 10 to 300 mg were responders if the posttreatment eliciting dose was 1000 mg or more. A threshold of 15% or more on the lower bound of a 95% CI around responder rate difference was prespecified to determine a positive trial result. Adverse event evaluation included collection of treatment-emergent adverse events (TEAEs).

RESULTS

Among 356 participants randomized (median age, 7 years; 61.2% male), 89.9% completed the trial; the mean treatment adherence was 98.5%. The responder rate was 35.3% with peanut-patch treatment vs 13.6% with placebo (difference, 21.7% [95% CI, 12.4%-29.8%; P < .001]). The prespecified lower bound of the CI threshold was not met. TEAEs, primarily patch application site reactions, occurred in 95.4% and 89% of active and placebo groups, respectively. The all-causes rate of discontinuation was 10.5% in the peanut-patch group vs 9.3% in the placebo group.

CONCLUSIONS AND RELEVANCE

Among peanut-allergic children aged 4 to 11 years, the percentage difference in responders at 12 months with the 250-μg peanut-patch therapy vs placebo was 21.7% and was statistically significant, but did not meet the prespecified lower bound of the confidence interval criterion for a positive trial result. The clinical relevance of not meeting this lower bound of the confidence interval with respect to the treatment of peanut-allergic children with epicutaneous immunotherapy remains to be determined.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT02636699.

A computerized decision support tool to implement asthma guidelines for children and adolescents

BACKGROUND

Multicenter randomized controlled trials (RCTs) for asthma management that incorporate usual-care regimens could benefit from standardized application of evidence-based guidelines.

OBJECTIVE

We sought to evaluate performance of a computerized decision support tool, the Asthma Control Evaluation and Treatment (ACET) Program, to standardize usual-care regimens for asthma management in RCTs.

METHODS

Children and adolescents with persistent uncontrolled asthma living in urban census tracts were recruited into 3 multicenter RCTs (each with a usual-care arm) between 2004 and 2014. A computerized decision support tool scored asthma control and assigned an appropriate treatment step based on published guidelines. Control-level determinants (symptoms, rescue medication use, pulmonary function measure, and adherence estimates) were collected at visits and entered into the ACET Program. Changes in control levels and treatment steps were examined during the trials.

RESULTS

At screening, more than half of the participants were rated as having symptoms that were not controlled or poorly controlled. The proportion of participants who gained good control between screening and randomization increased significantly in all 3 trials. Between 51% and 70% had symptoms that were well controlled by randomization. The proportion of well-controlled participants remained constant or improved slightly from randomization until the last posttreatment visit. Nighttime symptoms were the most common control-level determinant; there were few (<1%) instances of complete overlap of factors. FEV₁ was the driver of control-level assignment in 30% of determinations.

CONCLUSION

The ACET Program decision support tool facilitated standardized asthma assessment and treatment in multicenter RCTs and was associated with attaining and maintaining good asthma control in most participants.

AR101 Oral Immunotherapy for Peanut Allergy

BACKGROUND

Peanut allergy, for which there are no approved treatment options, affects patients who are at risk for unpredictable and occasionally life-threatening allergic reactions.

METHODS

In a phase 3 trial, we screened participants 4 to 55 years of age with peanut allergy for allergic dose-limiting symptoms at a challenge dose of 100 mg or less of peanut protein (approximately one third of a peanut kernel) in a double-blind, placebo-controlled food challenge. Participants with an allergic response were randomly assigned, in a 3:1 ratio, to receive AR101 (a peanut-derived investigational biologic oral immunotherapy drug) or placebo in an escalating-dose program. Participants who completed the regimen (i.e., received 300 mg per day of the maintenance regimen for approximately 24 weeks) underwent a double-blind, placebo-controlled food challenge at trial exit. The primary efficacy end point was the proportion of participants 4 to 17 years of age who could ingest a challenge dose of 600 mg or more, without dose-limiting symptoms.

RESULTS

Of the 551 participants who received AR101 or placebo, 496 were 4 to 17 years of age; of these, 250 of 372 participants (67.2%) who received active treatment, as compared with 5 of 124 participants (4.0%) who received placebo, were able to ingest a dose of 600 mg or more of peanut protein, without dose-limiting symptoms, at the exit food challenge (difference, 63.2 percentage points; 95% confidence interval, 53.0 to 73.3; P<0.001). During the exit food challenge, the maximum severity of symptoms was moderate in 25% of the participants in the active-drug group and 59% of those in the placebo group and severe in 5% and 11%, respectively. Adverse events during the intervention period affected more than 95% of the participants 4 to 17 years of age. A total of 34.7% of the participants in the active-drug group had mild events, as compared with 50.0% of those in the placebo group; 59.7% and 44.4% of the participants, respectively, had events that were graded as moderate, and 4.3% and 0.8%, respectively, had events that were graded as severe. Efficacy was not shown in the participants 18 years of age or older.

CONCLUSIONS

In this phase 3 trial of oral immunotherapy in children and adolescents who were highly allergic to peanut, treatment with AR101 resulted in higher doses of peanut protein that could be ingested without dose-limiting symptoms and in lower symptom severity during peanut exposure at the exit food challenge than placebo. (Funded by Aimmune Therapeutics; PALISADE ClinicalTrials.gov number, NCT02635776 .).

Multicenter, randomized, double-blind, placebo-controlled clinical trial of vital wheat gluten oral immunotherapy

BACKGROUND

Wheat is a common food allergen that can cause anaphylaxis.

OBJECTIVE

We sought to determine the efficacy and safety of vital wheat gluten (VWG) oral immunotherapy (OIT).

METHODS

After baseline double-blind, placebo-controlled food challenge (DBPCFC), 46 patients with wheat allergy (median age, 8.7 years; range, 4.2-22.3 years) were randomized 1:1 to low-dose VWG OIT or placebo, with biweekly escalation to 1445 mg of wheat protein (WP). After a year 1 DBPCFC, active subjects continued low-dose VWG OIT for another year and underwent a year 2 DBPCFC and, if passed, a subsequent off-therapy DBPCFC. Placebo-treated subjects crossed over to high-dose VWG OIT (maximum, 2748 mg of WP).

RESULTS

The median baseline successfully consumed dose (SCD) was 43 mg of WP in both groups. At year 1, 12 (52.2%) of 23 low-dose VWG OIT-treated and 0 (0%) of 23 placebo-treated subjects achieved the primary end point of an SCD of 4443 mg of WP or greater (P < .0001); median SCDs were 4443 and 143 mg, respectively. At year 2, 7 (30.4%) of 23 low-dose VWG OIT-treated subjects were desensitized to an SCD of 7443 mg of WP; 3 (13%) achieved sustained unresponsiveness 8 to 10 weeks off therapy. Among placebo-treated subjects who crossed over to high-dose VWG OIT, 12 (57.1%) of 21 were desensitized after 1 year (median SCD, 7443 mg of WP; nonsignificant vs low-dose VWG OIT). At year 1, skin prick test responses and wheat- and omega-5 gliadin-specific IgE levels did not differ between groups; the low-dose VWG OIT median specific IgG₄ level was greater than placebo (wheat, P = .0005; omega-5 gliadin, P = .0001). Year 1 SCDs correlated with wheat-specific (rho = 0.55, P = .0003) and omega-5 gliadin-specific (rho = 0.51, P = .001) IgG₄ levels in all subjects. Among 7822 low-dose VWG OIT doses in year 1, 15.4% were associated with adverse reactions: 0.04% were severe, and 0.08% subjects received epinephrine. Among 7921 placebo doses, 5.8% were associated with adverse reactions; none were severe.

CONCLUSIONS

Low- and high-dose VWG OIT induced desensitization in about one half of the subjects after 1 year of treatment. Two years of low-dose VWG OIT resulted in 30% desensitization, and 13% had sustained unresponsiveness.

Obstruction phenotype as a predictor of asthma severity and instability in children

BACKGROUND

Small-airways instability resulting in premature airway closure has been recognized as a risk for asthma severity and poor control. Although spirometry has limited sensitivity for detecting small-airways dysfunction, a focus on the air-trapping component of obstruction might identify a risk factor for asthma instability.

OBJECTIVE

We sought to use spirometric measurements to identify patterns of airway obstruction in children and define obstruction phenotypes that relate to asthma instability.

METHODS

Prebronchodilation and postbronchodilation spirometric data were obtained from 560 children in the Asthma Phenotypes in the Inner City study. An air-trapping obstruction phenotype (A Trpg) was defined as a forced vital capacity (FVC) z score of less than -1.64 or an increase in FVC of 10% of predicted value or greater with bronchodilation. The airflow limitation phenotype (A Limit) had an FEV1/FVC z score of less than -1.64 but not A Trpg. The no airflow limitation or air-trapping criteria (None) phenotype had neither A Trpg nor A Limit. The 3 obstruction phenotypes were assessed as predictors of number of exacerbations, asthma severity, and airway lability.

RESULTS

Patients with the A Trpg phenotype (14% of the cohort) had more exacerbations during the 12-month study compared with those with the A Limit (P < .03) and None (P < .001) phenotypes. Patients with the A Trpg phenotype also had the highest Composite Asthma Severity Index score, the highest asthma treatment step, the greatest variability in FEV1 over time, and the greatest sensitivity to methacholine challenge.

CONCLUSIONS

A Trpg and A Limit patterns of obstruction, as defined by using routine spirometric measurements, can identify obstruction phenotypes that are indicators of risk for asthma severity and instability.

Phenotypes of Recurrent Wheezing in Preschool Children: Identification by Latent Class Analysis and Utility in Prediction of Future Exacerbation

BACKGROUND

Recurrent preschool wheezing is a heterogeneous disorder with significant morbidity, yet little is known about phenotypic determinants and their impact on clinical outcomes.

OBJECTIVE

Latent class analysis (LCA) was used to identify latent classes of recurrent preschool wheeze and their association with future exacerbations and inhaled corticosteroid (ICS) treatment response.

METHODS

Data from 5 clinical trials of 1708 children aged 12 to 71 months with recurrent wheezing were merged. LCA was performed on 10 demographic, exposure, and sensitization variables to determine the optimal number of latent classes. The primary outcome was the annualized rate of wheezing exacerbations requiring systemic corticosteroids during the study intervention period; the secondary outcome was the time to first exacerbation. Exploratory analyses examined the effect of daily ICS treatment on exacerbation outcomes.

RESULTS

Four latent classes of recurrent wheezing were identified; these were not distinguished by current symptoms or historical exacerbations but differed with regard to allergen sensitization and/or exposures. Annualized exacerbation rates (mean ± SEM/year) were 0.65 ± 0.06 for class 1 ("minimal sensitization"), 0.93 ± 0.10 for class 2 ("sensitization with indoor pet exposure"), 0.60 ± 0.07 for class 3 ("sensitization with tobacco smoke exposure"), and 0.81 ± 0.10 for class 4 ("multiple sensitization and eczema") (P < .001). In a research setting of high adherence, daily ICS treatment improved exacerbation rates in classes 2 and 4 but not the other groups.

CONCLUSIONS

Sensitization and exposure assessments are useful in the prediction of future exacerbation and may identify children most likely to respond favorably to daily ICS treatment.

Quintupling Inhaled Glucocorticoids to Prevent Childhood Asthma Exacerbations

BACKGROUND

Asthma exacerbations occur frequently despite the regular use of asthma-controller therapies, such as inhaled glucocorticoids. Clinicians commonly increase the doses of inhaled glucocorticoids at early signs of loss of asthma control. However, data on the safety and efficacy of this strategy in children are limited.

METHODS

We studied 254 children, 5 to 11 years of age, who had mild-to-moderate persistent asthma and had had at least one asthma exacerbation treated with systemic glucocorticoids in the previous year. Children were treated for 48 weeks with maintenance low-dose inhaled glucocorticoids (fluticasone propionate at a dose of 44 μg per inhalation, two inhalations twice daily) and were randomly assigned to either continue the same dose (low-dose group) or use a quintupled dose (high-dose group; fluticasone at a dose of 220 μg per inhalation, two inhalations twice daily) for 7 days at the early signs of loss of asthma control ("yellow zone"). Treatment was provided in a double-blind fashion. The primary outcome was the rate of severe asthma exacerbations treated with systemic glucocorticoids.

RESULTS

The rate of severe asthma exacerbations treated with systemic glucocorticoids did not differ significantly between groups (0.48 exacerbations per year in the high-dose group and 0.37 exacerbations per year in the low-dose group; relative rate, 1.3; 95% confidence interval, 0.8 to 2.1; P=0.30). The time to the first exacerbation, the rate of treatment failure, symptom scores, and albuterol use during yellow-zone episodes did not differ significantly between groups. The total glucocorticoid exposure was 16% higher in the high-dose group than in the low-dose group. The difference in linear growth between the high-dose group and the low-dose group was -0.23 cm per year (P=0.06).

CONCLUSIONS

In children with mild-to-moderate persistent asthma treated with daily inhaled glucocorticoids, quintupling the dose at the early signs of loss of asthma control did not reduce the rate of severe asthma exacerbations or improve other asthma outcomes and may be associated with diminished linear growth. (Funded by the National Heart, Lung, and Blood Institute; STICS ClinicalTrials.gov number, NCT02066129 .).

Genome-wide association study of maternal genetic effects and parent-of-origin effects on food allergy

Previous genetic studies of food allergy (FA) have mainly focused on inherited genotypic effects. The role of parental genotypic effects remains largely unexplored. Leveraging existing genome-wide association study (GWAS) data generated from the Chicago Food Allergy Study, we examined maternal genotypic and parent-of-origin (PO) effects using multinomial likelihood ratio tests in 588 complete and incomplete Caucasian FA trios. We identified 1 single nucleotide polymorphism with significant (P < 5×10) maternal effect on any FA (rs4235235), which is located in a noncoding RNA (LOC101927947) with unknown function. We also identified 3 suggestive (P < 5×10) loci with maternal genetic effects: 1 for any FA (rs976078, in a gene desert region on 13q31.1) and 2 for egg allergy (rs1343795 and rs4572450, in the ZNF652 gene, where genetic variants have been associated with atopic dermatitis). Three suggestive loci with PO effect were observed: 1 for peanut allergy (rs4896888 in the ADGB gene) and 2 for any FA in boys only (rs1036504 and rs2917750 in the IQCE gene). Findings from this family-based GWAS of FA provided some preliminary evidence on maternal genotypic or PO effects on FA. Additional family-based studies are needed to confirm our findings and gain new insight into maternal and paternal genetic contribution to FA.

Overweight/obesity status in preschool children associates with worse asthma but robust improvement on inhaled corticosteroids

BACKGROUND

Overweight/obesity (OW) is linked to worse asthma and poorer inhaled corticosteroid (ICS) response in older children and adults.

OBJECTIVE

We sought to describe the relationships between OW and asthma severity and response to ICS in preschool children.

METHODS

This post hoc study of 3 large multicenter trials involving 2- to 5-year-old children compared annualized asthma symptom days and exacerbations among normal weight (NW) (body mass index: 10th-84th percentiles) versus OW (body mass index: ≥85th percentile) participants. Participants had been randomized to daily ICS, intermittent ICS, or daily placebo. Simple and multivariable linear regression was used to compare body mass index groups.

RESULTS

Within the group not treated with a daily controller, OW children had more asthma symptom days (90.7 vs 53.2, P = .020) and exacerbations (1.4 vs 0.8, P = .009) thanNW children did. Within the ICS-treated groups, OW and NW children had similar asthma symptom days (daily ICS: 47.2 vs 44.0 days, P = .44; short-term ICS: 61.8 vs 52.9 days, P = .46; as-needed ICS: 53.3 vs 47.3 days, P = .53), and similar exacerbations (daily ICS: 0.6 vs 0.8, P = .10; short-term ICS: 1.1 vs 0.8 days, P = .25; as-needed ICS: 1.0 vs 1.1, P = .72). Compared with placebo, daily ICS in OW led to fewer annualized asthma symptom days (90.7 vs 41.2, P = .004) and exacerbations (1.4 vs 0.6, P = .006), while similar protective ICS effects were less apparent among NW.

CONCLUSIONS

In preschool children off controller therapy, OW is associated with greater asthma impairment and exacerbations. However, unlike older asthmatic patients, OW preschool children do not demonstrate reduced responsiveness to ICS therapy.