Clinical Efficacy of Subcutaneous Allergen Immunotherapy in Patients with Atopic Dermatitis

Advancements in Allergen Immunotherapy for the Treatment of Atopic Dermatitis

Atopic dermatitis (AD) is a chronic inflammatory skin condition that affects individuals of all age groups, manifesting as a spectrum of symptoms varying from mild to severe. Allergen immunotherapy (AIT) involves the administration of allergen extracts and has emerged as a potential treatment strategy for modifying immune responses. Its pathogenesis involves epidermal barrier dysfunction, microbiome imbalance, immune dysregulation, and environmental factors. Existing treatment strategies encompass topical steroids to systemic agents, while AIT is under investigation as a potential immune-modifying alternative. Several studies have shown reductions in the severity scoring of atopic dermatitis (SCORAD) scores, daily rescue medication use, and visual analog scale (VAS) scores following AIT. Biomarker changes include increased IgG4 levels and decreased eosinophil counts. This review provides valuable insights for future research and clinical practice, exploring AIT as a viable option for the management of AD.

Allergen immunotherapy in China

Allergen immunotherapy (AIT) is an etiological treatment strategy that involves administering escalating doses of clinically relevant allergens to desensitize the immune system. It has shown encouraging results in reducing allergy symptoms and enhancing patients' quality of life. In this review, we offer a thorough overview of AIT in China, examining its efficacy, safety, current practices, and prospects. We further underscore the progress made in AIT research and clinical applications, as well as the distinct challenges and opportunities that China faces in this area.

Molecular profiling of allergen-antibody IgE might decide about the efficacy of allergen immunotherapy in a patient with atopic dermatitis and allergy to house dust mites

Introduction

Allergen immunotherapy (AIT) has no clear recommendation for atopic dermatitis (AD).

Aim

To evaluate the effect of AIT on house dust mites (HDM) in AD patients sensitised to HDM with different baseline molecular profiles of antigens.

Material and methods

In this placebo-controlled study, 61 patients with moderate-to-severe AD allergy symptoms and HDM allergy were included. They received a 12 months' AIT with the use of HDM allergen extract or placebo. The authors adopted their AD improvement criterion after 1 year of AIT as a reduction of all examined indicators by at least 50% from the baseline for %BSA, TMS, and EASI scores. Additionally, the influence of individual HDM molecules on the final AIT effect was analysed.

Results

Finally, from the 24 desensitised patients, 15 achieved a positive expected effect after 12 months of HDM AIT. None of the patients who received a placebo had an improvement in AD of at least 50% after 1 year of follow-up. Patients with polysensitisation less frequently achieved the expected HDM AIT effect than patients monosensitised to mites (p < 0.05). The presence of sensitisation to rDer p 1 (odds ratio = 4.35, 95% CI: 4.01-4.56) and/or rDer p 2 (OR = 2.16, 95% CI: 1.98-2.33) and/or rDer f 2 (OR = 1.41, 95% CI: 1.55-1.78) molecules significantly increased the efficacy of AIT. HDM AIT could be helpful for patients with moderate-to-severe AD and sensitised to HDM as an add-on therapy. Various HDM molecules may affect the effectiveness of the expected AIT effect. The presence of sensitisation to rDer p 1 (OR = 4.35, 95% CI: 4.01-4.56) and/or rDer p 2 (OR = 2.16, 95% CI: 1.98-2.33) and/or rDer f 2 (OR = 1.41, 95% CI: 1.55-1.78) molecules significantly increased the efficacy of AIT.

Conclusions

HDM AIT could be helpful for patients with moderate-to-severe AD and sensitised to HDM as an add-on therapy. Various HDM molecules may affect the effectiveness of the expected AIT.

The Effectiveness of Allergen Immunotherapy in Adult Patients with Atopic Dermatitis Allergic to House Dust Mites

Background and objectives: Allergen immunotherapy (AIT) is not a first-line therapy in atopic dermatitis (AD) and its effectiveness has been criticised. Objectives: The efficacy and safety of AIT in adult patients with AD and monosensitisation to house dust mites (HDMs) were investigated. Materials and Methods: A total of 37 patients were included in this double-blind, placebo-controlled study. Patients were eligible if they were diagnosed with AD; had moderate-to-severe AD according to the Eczema Area and Severity Index (EASI) with at least 7.1 points, the % BSA (body surface area) scale with at least 16 points, and the IsGA (investigator global assessment) scale with 3 points; had positive skin prick tests (SPTs); and were positive for the specific immunoglobulin E (sIgE) response to D. pteronyssinus and D. farinae extracts, as well as Der p 1 and Der f1. The patients received Purethal mites (20,000 AUeq/mL, HAL Allergy, Leiden, The Netherlands) with the extract allergens D. pteronyssinus and D. farinae (50/50%) or a placebo for 12 months. The primary outcomes included changes in EASI, % BSA, and IsGA due to SCIT between the start and after 12 months of therapy. Results: In the study group, significant improvement was observed in terms of the EASI score from 43 ± 8.2 to 21 ± 5.9 points, % BSA from 72 ± 18 to 28 ± 11 points, and IsGA from 4.5 ± 0.5 to 1.5 ± 0.5 points in comparison with the placebo after 1 year of AIT. Additionally, the proportion of patients who achieved success in the IsGA (IsGA < 2) was significantly better in comparison to the placebo with 13/20 (65%) vs. 4/14 (29%), respectively (p < 0.05). Conclusions: HDM-AIT effectively improved atopic dermatitis in patients that strictly qualified for desensitisation with a confirmed monovalent mite allergy.

[Retrospective Study of Mite-Specific Subcutaneous Immunotherapy in Children]

OBJECTIVE

To explore the clinical efficacy and influencing factors of children receiving mite-specific subcutaneous immunotherapy (SCIT).

METHODS

We retrospectively analyzed the data of children who had received mite SCIT for 3 years at the Desensitization Center of our hospital. We used the daily medication score (DMS) to evaluate the medication use status (the higher the score, the higher the amount of medications given and the less satisfactorily was the primary disease controlled) and we used the visual analogue scale (VAS) to evaluate clinical symptoms (the higher the score, the more severe the symptoms). Evaluation was performed after the first SCIT treatment and after treatment was given for 3 months, 4 months, 12 months, and 3 years. According to whether medication for the primary disease was stopped after 3 years, the patients were divided into two groups, the discontinued medication group (discontinued group) and the continued medication group (continued group). The general data, DMS, VAS and the decline rate of the two groups were compared, and logistic regression was performed to analyze the influencing factors of the outcome.

RESULTS

A total of 711 children were enrolled in the study, with an average age of 8.38 years at the time of the first visit to the hospital. There were 442 males and 269 females. Skin prick test showed that 445 cases only had mite allergy, and 266 cases had mite allergy combined with other allergies. 360 cases have discontinued the medication for the primary disease after 3 years, and 351 cases had relieved symptoms, but still needed to continue with the medication. At the beginning of SCIT treatment, the DMS and VAS of the discontinued group were lower than those of the continued group ( P<0.05). Evaluations from 3 months to 3 years showed that both DMS and VAS continued to decrease compared with those from the beginning, and the decline rate of DMS and VAS of the discontinued group was higher than that of the continued group after 3 years of SCIT ( P<0.05). After 3 months of SCIT, the positive rates of nasal and ocular symptoms in the discontinued group were lower than those in the continued group ( P<0.05). After 3 years of SCIT, the positive rates of nasal, ocular, and chest symptoms in the discontinued group were lower than those in the continued group ( P<0.05). Univariate analysis combined with multivariate logistic regression showed that initial DMS>4 points and initial VAS>3.5 points were protective factors for the discontinuation of the medication for the primary disease at the end of 3 years of SCIT, while the female sex and DMS reduction rate after 12 months of treatment>50% were risk factors for discontinuation.

CONCLUSIONS

Mite SCIT can help relieve clinical symptoms and reduce the use of medication for symptomatic treatment. Symptoms can be improved after 3 months of SCIT, with the fastest improvement shown in nasal and eye symptoms. It is not recommended to discontinue the medication for the primary disease for too much after 1 year of treatment.

Efficacy of transdermal immunotherapy with biodegradable microneedle patches in a murine asthma model

BACKGROUND

House dust mite (HDM) is a well-known cause of asthma. Allergen-specific immunotherapy (AIT) can only modify the natural course of the disease. Conventional routes of HDM AIT are subcutaneous or sublingual. Subcutaneous immunotherapy (SCIT) has a disadvantage of systemic hypersensitive reaction, and the sublingual immunotherapy has a disadvantage of local allergic reaction and low drug adherence.

OBJECTIVE

To overcome the weak points of conventional AIT, we developed a HDM loaded biodegradable microneedle patch (MNP) for transdermal immunotherapy (TDIT). We aim to demonstrate the efficacy of TDIT in murine asthma model triggered by HDM compared with conventional SCIT.

METHODS

To make HDM asthma mouse model, 5-week-old BALB/c female mice were sensitized and challenged by intranasal administration of HDM. The mice were divided into 5 groups: sham, asthma, low (10 µg) and high dose (100 µg) SCIT, and TDIT (10 µg). To make HDM loaded MNP, droplet-born air blowing method was used. Airway hyperresponsiveness and allergic inflammation markers were analysed by bronchoalveolar lavage fluid, immunohistochemistry, serum immunoglobulin (Ig) analysis, and lung cytokine assays.

RESULTS

Airway hyperresponsiveness was ameliorated by TDIT. Eosinophilic inflammation in bronchoalveolar lavage was improved without adverse reactions. Reduction of Th2 (IL-4, IL-5, and IL-13) cytokines, and HDM-specific IgE, induction of Treg (IL-10, TGF-β), Th1 (IFN-γ) cytokines were observed. Eosinophilic infiltration, goblet cell hyperplasia, and subepithelial fibrosis were also alleviated by TDIT. These changes were more significant in the TDIT group than in subcutaneous AIT group.

CONCLUSION

In conclusion, HDM loaded biodegradable TDIT is a novel treatment option to treat asthma which showed more effectiveness and may have better safety profiles than conventional SCIT.

Principles of Allergen Immunotherapy and Its Clinical Application in China: Contrasts and Comparisons with the USA

Allergen immunotherapy (AIT) for allergic rhinitis (AR), asthma, and other allergic diseases has developed quickly. House dust mite (HDM), Artemisia (wormwood), Humulus japonicus (Japanese hop), Alternaria alternata, and Cladosporium herbarum are the five most common inhalant allergens in China. AIT has been performed in China for over 60 years. With the support of the Chinese Medical Association (CMA) and the Chinese Medical Doctors Association (CMDA), the Chinese College of Allergy and Asthma (CCAA) was established in 2016 as a specialized branch of CDMA and is the main certification authority for AIT. Chinese allergists and scientists have made tremendous progress in the development of AIT. There have been many publications by Chinese allergists and scientists worldwide encompassing original research studies, systematic reviews, case studies, and clinical trials. Currently, conventional subcutaneous immunotherapy (SCIT) is the preferred AIT in China, but sublingual immunotherapy (SLIT) is beginning to gain recognition. An increasing number of clinical trials have been conducted to investigate the clinical efficacy and side effects of SLIT and SCIT. In China, HDM is the only commercial standardized allergen extracts in clinical use, whereas the others are crude allergen extracts. Besides standardized allergen extracts, other forms of hypoallergenic extracts are still being investigated and developed in China. Immunotherapy in China is similar to that in the USA in which allergen extracts can be mixed for SCIT. However, allergen extracts cannot be mixed for SCIT in Europe.

Safety of Ultra-rush Schedule of Subcutaneous Allergen Immunotherapy With House Dust Mite Extract Conducted in an Outpatient Clinic in Patients With Atopic Dermatitis and Allergic Rhinitis

PURPOSE

Ultra-rush schedule of subcutaneous allergen immunotherapy (UR-SCIT) administering maximum maintenance dose of allergen extract within one day can save time and effort for allergen immunotherapy in patients with allergic disease. However, UR-SCIT is associated with an increased risk of systemic reaction (SR) and typically has been conducted in a hospital admission setting. To overcome disadvantages of UR-SCIT, we evaluated the safety of UR-SCIT conducted in an outpatient clinic in patients with atopic dermatitis (AD) and allergic rhinitis (AR).

METHODS

UR-SCIT was performed in 538 patients with AD and/or AR sensitized to house dust mite (HDM). A maximum maintenance dose of tyrosine-adsorbed HDM extract (1 mL of maintenance concentration) was divided into 4 increasing doses (0.1, 0.2, 0.3, and 0.4 mL) and administered to the patients by subcutaneous injection at 2-hour intervals for 8 hours in an outpatient clinic. SRs associated with UR-SCIT were classified according to the World Allergy Organization grading system.

RESULTS

SR was observed in 12 of 538 patients (2.2%) with AD and/or AR during UR-SCIT. The severity grades of the observed SRs were mild-to-moderate (grade 1 in 7 patients, grade 2 in 4 patients, and grade 3 in 1 patient). The scheduled 4 increasing doses of HDM extract could be administered in 535 of 538 patients (99.4%) except 3 patients who experienced SR before administration of the last scheduled dose. SR was observed within 2 hours in 11 patients after administration of the scheduled doses of HDM extract except one patient who experienced a grade 2 SR at 5.5 hours after administration of the last scheduled dose.

CONCLUSIONS

UR-SCIT with tyrosine-adsorbed HDM extract conducted in an outpatient clinic was tolerable in patients with AD and AR. UR-SCIT can be a useful method to start a SCIT in patients with AD and AR.

A Systematic Scoping Literature Review of Publications Supporting Treatment Guidelines for Pediatric Atopic Dermatitis in Contrast to Clinical Practice Patterns

INTRODUCTION

Treatment guidelines endorse a variety of strategies for atopic dermatitis (AD) which may vary from published data and clinical practice patterns. The objective of this review was to quantify the volume of available medical literature supporting pediatric AD treatments and compare these patterns to those recommended by published guidelines and/or clinical practice patterns.

METHODS

Searches of Embase (2005-2016) and abstracts from selected meetings (2014-2016) related to AD treatment in patients younger than 17 years of age yielded references that were assessed by study design, primary treatment, age groups, and AD severity.

RESULTS

Published literature partially supports clinical guidelines, with emollients and topical medications being the most investigated. There were disproportionately more publications for topical calcineurin inhibitors (TCI) compared with topical corticosteroids (TCS); however, the search interval may have biased the results toward treatments approved near the beginning of the time frame. In contrast, publications documenting clinical practice patterns reflect greater use of emollients and TCS (over TCI), as well as systemic corticosteroids. Data is relatively limited for long-term and combination treatment, treatment of severe AD, and patients younger than 2 years of age, and completely lacking for systemic corticosteroids.

CONCLUSION

This scoping review demonstrates that available medical literature largely supports published guidelines for topical therapy; however, clinical practice patterns are less aligned. There is a lack of data for older, more frequently used generic treatments, including oral antihistamines, oral antibiotics, and systemic corticosteroids. Overall, literature is lacking for long-term treatment, treatment for patients younger than 2 years of age, and for systemic treatment for severe disease.

FUNDING

Regeneron Pharmaceuticals Inc.

Efficacy and safety of fezakinumab (an IL-22 monoclonal antibody) in adults with moderate-to-severe atopic dermatitis inadequately controlled by conventional treatments: A randomized, double-blind, phase 2a trial

BACKGROUND

Interleukin 22 promotes epidermal hyperplasia and inhibits skin barrier function.

OBJECTIVE

Evaluate interleukin 22 blockade in adults with moderate-to-severe atopic dermatitis (AD).

METHODS

We performed a randomized, double-blind, placebo-controlled trial with intravenous fezakinumab monotherapy every 2 weeks for 10 weeks, with follow-up assessments until 20 weeks. The change in SCOring AD (SCORAD) score from baseline at 12 weeks served as the primary end point.

RESULTS

At 12 weeks, the mean declines in SCORAD for the entire study population were 13.8 ± 2.7 in the fezakinumab arm and 8.0 ± 3.1 in the placebo arm (P = .134). In the severe AD patient subset (with a baseline SCORAD of ≥50), SCORAD decline was significantly stronger in the drug-treated patients than placebo-treated patients at 12 weeks (21.6 ± 3.8 vs 9.6 ± 4.2, P = .029) and 20 weeks (27.4 ± 3.9 vs 11.5 ± 5.1, P = .010). At 12 weeks, improvements in body surface area involvement in the entire population were significantly stronger in the drug-treated than placebo-treated patients (12.4% ± 2.4 vs 6.2% ± 2.7; P = .009), and in the severe AD subset, the decline in Investigator Global Assessment was significantly higher in the drug-treated than placebo-treated patients (0.7 ± 0.2 vs 0.3 ± 0.1; P = .034). All scores showed progressive improvements after last dosing (10 weeks) until end of study (20 weeks). Common adverse events were upper respiratory tract infections.

LIMITATIONS

The limited sample size and lack of assessment with Eczema Area and Severity Index and a pruritus numerical rating scale were limiting factors. Significance was primarily obtained in severe AD.

CONCLUSION

Fezakinumab was well-tolerated, with sustained clinical improvements after last drug dosing.

Immunomodulatory effects induced by intramuscular administration of autologous total immunoglobulin G in patients with atopic dermatitis

BACKGROUND

Polyvalent human immunoglobulin G (IgG) preparations produced from the plasma pools of healthy blood donors have been used for the treatment of various autoimmune diseases and allergic diseases because of their anti-inflammatory and immunomodulatory effects. We hypothesized that intramuscular administration of autologous total IgG would induce immunomodulatory effects in patients with allergic diseases, based on the clinical efficacy of autologous blood therapy in patients with atopic dermatitis (AD).

METHODS

Sixteen adult AD patients with IgE-mediated sensitization to the house dust mite (Dermatophagoides farinae) received intramuscular injections of 50 mg autologous total IgG twice a week for 4 weeks. The serum levels of IgE, IgG, and IgG4 antibodies to the recombinant group 2 major allergen of Dermatophagoides farinae (Der f 2) and serum levels of interleukin (IL)-10, IL-4, IL-12, and interferon gamma (IFN-γ) were measured by enzyme-linked immunosorbent assay at baseline and at weeks 4, 8, and 12.

RESULTS

The serum level of IgE antibodies to Der f 2 was significantly decreased at 12 weeks compared with baseline (p<0.005). The serum levels of IgG and IgG4 antibodies to Der f 2 were significantly increased at 4, 8, and 12 weeks compared with baseline (p<0.05). The serum levels of IL-10 and IFN-γ were significantly increased at 4, 8, and 12 weeks compared with baseline (p<0.05). There were no significant differences in the serum levels of IL-4 or IL-12 before and after intramuscular administrations of autologous total IgG (p>0.05).

CONCLUSION

Intramuscular administration of autologous total IgG induced anti-allergic immunomodulatory effects in AD patients. Further studies are required to evaluate the detailed immunological mechanism underlying these effects.

Clinical Diversity of Atopic Dermatitis: A Review of 5,000 Patients at a Single Institute

PURPOSE

Atopic dermatitis (AD) is a chronic eczematous dermatitis that has a high prevalence and diverse clinical features. Although several hypotheses about its multifactorial pathogenesis have been suggested, the cause is not yet fully understood. A better understanding of the clinical features may helpful inelucidating the pathogenesis of AD.

METHODS

This retrospective study analyzed the questionnaires, medical charts, and laboratory examination results of 5,000 patients diagnosed with AD at a single tertiary hospital in Korea.

RESULTS

The demographics, allergic comorbidities, family history, severity, and treatment experiences of the patients were analyzed. Most of the patients were adults, 76.3% of whom were classified as havingan extrinsic type of AD. The mean eczema area and severity index (EASI) score was found to be 13.68, and adult patients were found to have higher severity than the other age groups. The anatomical involvements were different among the age groups, with more involvements of the head and neck in adults. The patients reported seasonal changes and stress as the factors that aggravated their symptoms the most. Topical steroids and oral cyclosporine were the most used medications at our clinic, whereas 10.1% of the patients underwent allergen-specific immunotherapy.

CONCLUSIONS

This analysis of 5,000 patients would lead to a better understanding of various subtypes and diverse clinical features of AD in Koreans. Distinct characteristics were observed among different age groups; thus, treatment strategies may need to be differentiated accordingly.