Effects of sublingual immunotherapy for multiple or single allergens in polysensitized patients

The KAAACI Guidelines for Sublingual Immunotherapy

Allergen immunotherapy is regarded as the only disease-modifying treatment option for various allergic conditions, including allergic rhinitis and asthma. Among the routes of administration of allergens, sublingual immunotherapy (SLIT) has gained clinical interest recently, and the prescription of SLIT is increasing among patients with allergies. After 30 years of SLIT use, numerous pieces of evidence supporting its efficacy, safety, and mechanism allows SLIT to be considered as an alternative option to subcutaneous immunotherapy. Based on the progressive development of SLIT, the current guideline from the Korean Academy of Asthma, Allergy, and Clinical Immunology aims to provide an expert opinion by allergy, pediatrics, and otorhinolaryngology specialists with an extensive literature review. This guideline addresses the use of SLIT, including 1) mechanisms of action, 2) appropriate patient selection for SLIT, 3) the currently available SLIT products in Korea, and 4) updated information on its efficacy and safety. This guideline will facilitate a better understanding of practical considerations for SLIT.

The Art of Immunotherapy

Selection of a patient with rhinitis/conjunctivitis or asthma for allergy immunotherapy (AIT) requires several decisions. First, does the patient's sensitization, pattern of exposure to an allergen, and degree of exposure to that allergen reasonably suggest a causal relationship? Does the level and duration of symptoms warrant the cost and inconvenience of immunotherapy, or is the patient motivated by the disease-modifying potential of AIT? If AIT is selected, is the choice to be greater safety and convenience with sublingual immunotherapy (SLIT) tablets, but with treatment probably limited to 2 or 3 allergens, or for subcutaneous immunotherapy where multiple allergen therapy is the rule and efficacy may be somewhat greater, at least initially, or does the physician go off-label into the unknowns of liquid SLIT? Are there extracts of sufficient potency to achieve likely effective doses? How does the physician deal with large local or systemic reactions, with gaps in treatment, with pollen seasons, and the use of premedication or cautionary prescription of epinephrine autoinjectors? How can adherence to AIT be improved? These and other questions are addressed in this paper.

Efficacy of dual sublingual immunotherapy with Japanese cedar pollen and house dust mite allergens in patients with allergic rhinitis sensitized to multiple allergens

OBJECTIVE

In the present study, we examined the effects of dual sublingual immunotherapy (SLIT) with Japanese cedar pollen (JCP) and house dust mite (HDM) allergens on nasal symptoms during the peak pollen period (PPP) and in late fall (LF) in patients with allergic rhinitis (AR) sensitized to both JCP and HDM. We then compared the efficacy of dual-SLIT with JCP and HDM to that of mono-SLIT with JCP at PPP.

METHODS

Twenty-five bisensitized patients with AR who showed positive serum specific immunoglobulin E (IgE) against both JCP and HDM were enrolled. In dual-SLIT, 16 patients received JCP drops/tablets and HDM tablets concurrently. In mono-SLIT with JCP, nine patients received JCP drops/tablets. Nasal symptoms were scored on a 0-4 point scale.

RESULTS

The nasal scores at PPP and in LF in the bisensitized patients with AR who received dual-SLIT with JCP and HDM in 2019 were significantly lower than those in the same patients who received antihistamines only in 2018. The decrease in scores of nasal obstruction at PPP from 2018 to 2019 in patients who received dual-SLIT was significantly greater than those in patients who received mono-SLIT with JCP. Dual-SLIT was well tolerated and only had mild adverse effects.

CONCLUSION

These findings suggest that dual-SLIT suppressed both JCP-induced seasonal and HDM-induced perennial nasal symptoms in bisensitized patients with AR. Dual-SLIT was more effective in suppressing nasal obstruction at PPP than mono-SLIT with JCP with limitation of baseline characteristics not to be controlled between the two groups, suggesting that dual-SLIT suppressed HDM-induced priming effects, thus resulting in further suppression of nasal obstruction at PPP.

LEVEL OF EVIDENCE

3b, a case-controlled study.

To mix or not to mix in allergy immunotherapy vaccines

PURPOSE OF REVIEW

European and US allergists generally do not agree on the approach to subcutaneous allergy immunotherapy in patients with multiple allergies. The North American approach is to treat with a mixture that contains all the allergen extracts to which the patient has evident clinical sensitivity, whereas the European approach is to select for treatment the one or at the most two allergens that are clinically most important for the patient.

RECENT FINDINGS

Recent society guidelines continue to recommend these differing practices of treating the polyallergic patient and reviews of prescribing practices indicate these divergent recommendations are followed in Europe and the USA.

SUMMARY

The objections by European allergists to the practice by US allergists are that multiallergen immunotherapy leads to dilution of allergens to less than effective doses, that proteases in some extracts can degrade allergens in other extracts, that there is a problem of safety and inability to determine which component extract caused a systemic reaction, and finally that there is alack of convincing studies demonstrating efficacy of multiallergen mixtures. Each of these contentions is addressed.

Clinical effectiveness of house dust mite immunotherapy in mono- versus poly-sensitised patients with allergic rhinitis: a systematic review and meta-analysis

Selecting an appropriate allergen-specific immunotherapy (AIT) regimen for polysensitised allergic rhinitis (AR) patients is challenging for clinicians. Although previous studies showed comparable effectiveness of single-allergen AIT with house dust mite (HDM) extract between monosensitised and polysensitised AR patients, there is no systematic review and meta-analysis demonstrating the comparable effectiveness of HDM AIT. In this meta-analysis, we analysed nine studies to compare the clinical effectiveness of HDM AIT. The primary outcome was nasal symptom score and secondary outcomes were medication and quality of life scores. The changes in nasal symptom score after HDM AIT did not significantly differ between monosensitised and polysensitised patients. The clinical effectiveness of HDM AIT regarding medication and quality of life score was not significantly different between monosensitised and polysensitised patients). In conclusion, single-allergen AIT with HDM extract showed comparable clinical effectiveness between polysensitised and monosensitised patients with AR.

Recent Advances in Allergen-Specific Immunotherapy as Treatment for Allergic Asthma: A Practical Overview

The Global Initiative for Asthma Report updated in 2019 stated that potential benefits of allergen immunotherapy (AIT), compared to pharmacological and avoidance options, must be weighed against the risk of adverse effects and the inconvenience and cost of the prolonged course of therapy in asthma. Thus, with the aim of clarifying some aspects with regard to the possible use of AIT in allergic asthma treatment armamentarium, a group of expert allergists from the Spanish Allergy and Clinical Immunology Scientific Society (SEAIC), particularly from the Immunotherapy and Asthma Interest Groups developed a frequently asked questions in clinical practice. This document updates relevant topics on the use of AIT in asthma and could facilitate physician clinical decisions and improve health outcomes for individual patients.

Preference for Immunotherapy with Tablets by People with Allergic Rhinitis

BACKGROUND

People with allergic rhinitis (AR) who are not controlled on conventional therapy can be treated using allergy immunotherapy (AIT) administered as tablets, injections or drops. In the US, the use of sublingual immunotherapy as tablets (SLIT-tablets) is limited in comparison to subcutaneous immunotherapy (SCIT).

OBJECTIVE

This study investigated patients' preference for SLIT-tablets vs monthly or weekly SCIT from a US patient perspective.

METHODS

We carried out a discrete choice experiment (DCE) consisting of two blocks with eight choice sets. Adults and caregivers of children with moderate-to-severe AR were included if they had not previously or were not currently receiving AIT. Three attributes were included in the design: the mode and frequency of administration, the risk of systemic reactions and the co-payment.

RESULTS

A total of 724 adults with AR and 665 caregivers of children with AR were included in the study. Both adults and caregivers had a significant preference for SLIT-tablets compared with both weekly and monthly injections and for less risk of anaphylactic shock. Caregivers were more risk-averse than adults when choosing their treatment, and the younger the child, the more risk-averse the caregiver. The preference for SLIT-tablets was found for both monoallergic and polyallergic adults and caregivers of monoallergic and polyallergic children. Respondents not wanting AIT for free were more risk-averse than those indicating that they wanted AIT for free.

CONCLUSION

Our findings suggest that SLIT-tablets is the preferred route of administration for AIT among adults and caregivers of children with AR.

The evolution of allergy immunotherapy

OBJECTIVE

The objective of this review is to trace the evolution of the art and science of allergy immunotherapy (AIT).

DATA SOURCES

Original reports relating to the evolution of the concept of respiratory allergy and its specific treatment were identified by following references in journal articles, review articles, and allergy textbooks from the mid-20th century to the present.

STUDY SELECTIONS

Studies highlighting substantial milestones in the evolution of the practice of allergy immunotherapy were included.

RESULTS

The story of AIT begins with the recognition of hay fever as a distinct entity and subsequent studies that established grass pollen as one of the causes. This knowledge led several investigators, most notable Leonard Noon and John Freeman who worked at St. Mary's Hospital in London, to attempt to induce tolerance giving grass pollen extract by injection to their patients. After the publication of the work of Noon and Freeman in 1911, the practice of AIT spread rapidly and was applied to many other pollen allergens besides grass and for perennial rhinitis and asthma. The early studies were largely anecdotal, but over the past 60 to 70 years, studies of AIT have been conducted with increasingly sophisticated scientific methods. Nowadays, not only is the practice of AIT based on carefully conducted studies, but the underlying immunologic basis of allergy and the response to AIT have also been and still are being firmly established.

CONCLUSION

Both the art and the science behind the practice of AIT have been established by a solid base of clinical and immunologic studies.

Compromising between European and US allergen immunotherapy schools: Discussions from GUIMIT, the Mexican immunotherapy guidelines

Background

Allergen immunotherapy (AIT) has a longstanding history and still remains the only disease-changing treatment for allergic rhinitis and asthma. Over the years 2 different schools have developed their strategies: the United States (US) and the European. Allergen extracts available in these regions are adapted to local practice. In other parts of the world, extracts from both regions and local ones are commercialized, as in Mexico. Here, local experts developed a national AIT guideline (GUIMIT 2019) searching for compromises between both schools.

Methods

Using ADAPTE methodology for transculturizing guidelines and AGREE-II for evaluating guideline quality, GUIMIT selected 3 high-quality Main Reference Guidelines (MRGs): the European Academy of Allergy, Asthma and Immunology (EAACI) guideines, the S2k guideline of various German-speaking medical societies (2014), and the US Practice Parameters on Allergen Immunotherapy 2011. We formulated clinical questions and based responses on the fused evidence available in the MRGs, combined with local possibilities, patient's preference, and costs. We came across several issues on which the MRGs disagreed. These are presented here along with arguments of GUIMIT members to resolve them. GUIMIT (for a complete English version, Supplementary data) concluded the following.

Results

Related to the diagnosis of IgE-mediated respiratory allergy, apart from skin prick testing complementary tests (challenges, in vitro testing and molecular such as species-specific allergens) might be useful in selected cases to inform AIT composition. AIT is indicated in allergic rhinitis and suggested in allergic asthma (once controlled) and IgE-mediated atopic dermatitis. Concerning the correct subcutaneous AIT dose for compounding vials according to the US school: dosing tables and formula are given; up to 4 non-related allergens can be mixed, refraining from mixing high with low protease extracts. When using European extracts: the manufacturer's indications should be followed; in multi-allergic patients 2 simultaneous injections can be given (100% consensus); mixing is discouraged. In Mexico only allergoid tablets are available; based on doses used in all sublingual immunotherapy (SLIT) publications referenced in MRGs, GUIMIT suggests a probable effective dose related to subcutaneous immunotherapy (SCIT) might be: 50-200% of the monthly SCIT dose given daily, maximum mixing 4 allergens. Also, a table with practical suggestions on non-evidence-existing issues, developed with a simplified Delphi method, is added. Finally, dissemination and implementation of guidelines is briefly discussed, explaining how we used online tools for this in Mexico.

Conclusions

Countries where European and American AIT extracts are available should adjust AIT according to which school is followed.

Planning and approach to allergen-specific immunotherapy in polyallergic patients

Allergy immunotherapy (AIT) is currently the only disease-modifying treatment for allergic-respiratory diseases. Polysensitization may increase the severity of current disease resulting in subsequent asthma development in patients with allergic rhinitis. Due to the absence of general recommendations for the practical approach to polysensitized patients, clinical management is not standardized. The correlation between sensitizations and clinical symptoms, elimination of possible pollen cross-reactivities and principles of homologous allergen groups will guide the allergists to deduce the most relevant allergens for AIT. In the highlight of the previously proposed approach strategies to polyallergic patients, hereby we propose a revised practical stepwise approach based on the current European Medicine Agency (EMA) guidelines. However, more supporting data from well-designed, controlled, future studies are needed to improve clinical management recommendations for AIT in polyallergic patients.

30 years of sublingual immunotherapy

Allergen Immunotherapy (AIT) was introduced in clinical practice on an empirical basis more than 100 years ago. Since the first attempts, AIT was administered subcutaneously. Indeed, other routes of administration were proposed and studied, in particular to improve the safety, but only the sublingual route (SLIT) achieved a credibility based on evidence and was then accepted as a viable "alternative" option to the subcutaneous route. SLIT was largely used in clinical trials and clinical practice in this last 30 years. Thus, a large amount of data is available, coming from either controlled trials and postmarketing surveillance studies. It is clear that SLIT is overall effective, but it is also clear that the efficacy is not "class-related," as derived from meta-analyses, but restricted to each specific product. The 30-year lasting use of SLIT allowed to clarify many clinical aspects, such as efficacy, safety, use in asthma, regimens of administration, and optimal doses. In parallel, the mechanisms of action of AIT were elucidated, and new indications were proposed (eg food allergy, atopic dermatitis). In addition, the introduction of molecular-based diagnosis, allowed to better refine the prescription of SLIT, based on specific sensitization profiles. The present article will describe the origin and evolution of SLIT for respiratory allergy, taking into account the clinical context that suggested this form of treatment, the recently developed aspects, the future perspectives and unmet needs, This is not, therefore, a systematic review, rather a narrative historical description of the past history, and a look forward to the future opportunities.

[Effect of sublingual immunotherapy on patients with allergic rhinitis]

Objective:Study the efficacy of sublingual immunotherapy （SLIT） for monosensitized and polysensitized allergic rhinitis patients of different severity. Method:According to the results of intradermal experiments, 186 patients with AR who were treated with standardized dust mites SLIT for 2 years. These patients have been divided into mild monosensitized group and mild polysensitized group, moderate monosensitized group and moderate polysensitized group, severe monosensitized group and severe polysensitized group. Statistics and analysis of total nasal symptom score （TNSS）, total medication score （TMS） , visual analog scale （VAS） about before and after SLIT treatment. Result:Before SLIT treatment and after 2 years, the TNSS: Mild monosensitized group （5. 58±1. 68）（0. 58±0. 75）, mild polysensitized group（5. 34±1. 49）（0. 93±0. 75）;moderate monosensitized group （4. 68±1. 55）（0. 32±0. 63）, moderate polysensitized group（6. 26±1. 46）（0. 61±0. 67）,which have showed a statistically significant difference（P<0.05）,between the two groups have no significant difference （P>0.05）. Severe monosensitized group（6. 26±0. 73）（1. 16±1. 13）, severe polysensitized group（6. 49±1. 04）（1. 89±1. 07）, which have showed a statistically significant difference（P<0.05）, between the two groups have a statistically significant difference（P<0.05）. The VAS:Mild monosensitized group （6. 09±1. 23）（1. 52±1. 25）, mild polysensitized group（6. 21±0. 90）（1. 97±1. 18）,moderate monosensitized group（6. 12±0. 53）（1. 16±1. 03）, moderate polysensitized group（6. 65±1. 08）（1. 65±0. 98）,which have showed a statistically significant difference（P<0.05）,between the two groups have no significant difference （P>0.05）. Severe monosensitized group（6. 26±0. 73）（1. 16±1. 13）, severe polysensitized group（6. 49±1. 04）（1. 89±1. 07）, which have showed a statistically significant difference（P<0.05）, between the two groups have a statistically significant difference（P<0.05）. The TMS:These have showed a statistically significant difference（P<0.05）with same group,between all groups have no significant difference （P>0.05）. Conclusion:Dust mites under the SLIT are effective for monosensitized and polysensitized allergic patients. For patients with severe polysensitized , it is necessary to extend the treatment time （>2 years）.

Efficacy and safety of sublingual dust mite drops in children with mono- or polysensitized allergic rhinitis

OBJECTIVE

To explore the efficacy and safety of sublingual house dust mite (HDM) drops in children with mono- or polysensitized allergic rhinitis.

METHODS

We conducted a retrospective cohort study of 65 children with monosensitized AR and 118 children with polysensitized AR who were scheduled for sublingual administration of HDM drops from January 2015 to June 2016. Interleukin (IL)-2, IL-4, and IL-17α, transforming growth factor-β1 (TGF-β1), specific immunoglobulin E (IgE), and specific IgG4 were detected by ELISA. The efficacies were assessed using symptoms score and medication score. All the outcomes were measured 1 month before the study and 1 month after the end of the 2-year treatment.

RESULTS

The total nasal symptoms score (TNSS) decreased significantly from 11.27 (9.81 ± 12.73) at baseline to 3.48(1.98 ± 4.98) at the end of sublingual treatment for the monosensitized AP group (t = 30.00, P < 0.01), and from 11.54(10.04 ± 13.04) to 3.56 (2.00 ± 5.16) for the polysensitized AR group (t = 40.05, P < 0.01), respectively. IL-2 and TGF-β1 increased significantly after treatment in contrast with before treatment in both the monosensitized group and the polysensitized group (both P < 0.01). In contrast, IL-4 and IL-17α decreased significantly after treatment compared with the baseline in both groups (both P < 0.01). Sublingual HDM drops were generally safe and well tolerant in both groups.

CONCLUSIONS

This study confirmed the efficacy and safety of sublingual AIT in both monosensitized and polysensitized AR patients (Chinese children).

SCIT Versus SLIT: Which One Do You Recommend, Doc?

Allergic rhinitis is a prevalent condition that has a significant impact on the quality of life of many patients. When initial therapy fails to control the symptoms, allergen immunotherapy (AIT) has been suggested as an option by the Joint Task Force on Practice Parameters. The 2 main forms of AIT are via subcutaneous and sublingual routes, called subcutaneous immunotherapy and sublingual immunotherapy, respectively. There is debate about which is the better option for patients with each method offering its own pros and cons. We present 2 patients with allergic rhinitisAR that were deemed good candidates for AIT and explore current evidence for both subcutaneous immunotherapy and sublingual immunotherapy. The advantages and disadvantages of each method are discussed with the goal of providing a framework for the physician when deciding on AIT for their patients. In addition, we explore the use of AIT in patients with asthma and atopic dermatitis as potential patient populations that may benefit from the treatment. We use the discussion to provide recommendations regarding which method of AIT is best suited for both our patients.

Mind the gaps: Clinical trial concepts to address unanswered questions in aeroallergen immunotherapy-An NIAID/AHRQ Workshop

The Agency for Healthcare Research and Quality and the National Institute of Allergy and Infectious Diseases organized a workshop to develop trial concepts that could improve the use and effectiveness of aeroallergen immunotherapy (AAIT). Expert groups were formed to accomplish the following tasks: (1) propose a study design to compare the effectiveness and safety of subcutaneous versus sublingual AAIT; (2) propose a study design to compare the effectiveness and safety of AAIT by using 1 or a few allergens versus all or most allergens to which a patient is sensitized; (3) propose a study design to determine whether AAIT can alter the progression of childhood allergic airways disease; and (4) propose a study design to determine the optimal dose and duration of AAIT to achieve maximal effectiveness with acceptable safety. Study designs were presented by the workgroups, extensively discussed at the workshop, and revised for this report. The proposed trials would be of long duration and require large highly characterized patient populations. Scientific caveats and feasibility matters are discussed. These concepts are intended to help the development of clinical trials that can address some of the major questions related to the practice of AAIT for the management and prevention of allergic airways disease.

Clinical Response to Subcutaneous Dermatophagoides pteronyssinus Immunotherapy in Children with Allergic Rhinitis and Asthma Is Independent of Sensitization to Blomia tropicalis Allergens

BACKGROUND

Dermatophagoides pteronyssinus (DP) and Blomia tropicalis (BT) are the dominant house dust mites inducing allergic diseases in tropical climates. It is not known whether the efficacy of DP subcutaneous immunotherapy (SCIT) is similar in patients sensitized to DP alone or to both DP and BT.

METHOD

Ninety-five children (5-17 years old) affected by asthma with rhinitis and sensitized to both DP and BT received 3 years of DP-SCIT. Clinical symptom and medication scores, serum-specific IgE and IgG4 were evaluated during DP-SCIT. Patients were grouped based on DP and BT co-sensitization or cross-reactivity, according to positive or negative IgE to BT major allergen (BTMA).

RESULTS

After 3 years of DP-SCIT, all patients had significant reductions in symptoms and medication use. In all, 65% of the patients were free of asthma symptoms and medication use; in addition, 3% was free of rhinitis symptoms. FEV1 in all patients were greater than 95% of predicted. DP-SCIT induced significant increases in DP- and BT-specific IgG4. In 50% of patients, DP-specific IgG4 increased more than 67-fold. BT-specific IgG4 increased more than 2.5 fold. A moderate correlation (r = 0.48-0.61, p < 0.01) was found between specific IgE against DP and BT in the BTMA- group (n = 34) before and after DP-SCIT, whereas no correlation was found in the BTMA+ group (n = 61). The 2 BTMA groups responded similarly with regard to clinical improvement and increase in specific IgG4 to both DP and BT. No safety finding of concern were reported in either group.

CONCLUSION

DP-SCIT may be of clinical benefit to patients with IgE sensitizations to both DP and BT. DP-SCIT induces IgG4 that cross-react with BT allergens.

Ragweed allergy immunotherapy tablet MK-3641 (Ragwitek®) for the treatment of allergic rhinitis

INTRODUCTION

Allergic rhinitis (AR) is among the most common chronic conditions affecting both children and adults. It is the cause of significant morbidity from the symptoms and interference with sleep. It results in major impairment of performance both at school and at work. In the U.S. and certain parts of Europe, ragweed pollen is a major cause of seasonal AR. In 2014, the U.S. Food and Drug Administration (FDA) approved a sublingual ragweed tablet (MK-3641) for use in adults with ragweed-induced AR. Areas covered: This paper will review the impact of ragweed-induced AR and available treatments including subcutaneous immunotherapy and studies with MK-3641. The principal search method was PubMed. Expert commentary: One dosing finding, two 28-day safety and two 52-week safety and efficacy studies have been conducted with MK-3641. The 12-U (12μg Amb a 1) tablet was the most effective. Local application site reactions were common but usually not serious. Only one, non-serious systemic reaction was reported in four safety studies. MK-3641 is a safe and effective treatment for ragweed-pollen-induced AR when treatment is initiated ≥ 12 weeks prior to the onset of the ragweed pollen season.

Efficacy of add-on sublingual immunotherapy for adults with asthma: A meta-analysis and systematic review

BACKGROUND

Sublingual immunotherapy (SLIT) reduces symptom scores and the use of rescue medication in children with allergic asthma, but the effect of SLIT therapy in adult patients has not been reported.

OBJECTIVE

To examine the efficacy and adverse effects of SLIT add-on vs conventional medication in adult patients with mild to moderate asthma.

METHODS

We systematically searched the MEDLINE, Embase, Cochrane, and Central databases. Eligible studies included adult patients with allergic asthma who received either SLIT or standard care. Standard mean differences were used as measures of efficacy in a random-effects model.

RESULTS

Twenty trials that included 2,288 patients in the SLIT add-on group and 1,268 patients in the traditional therapy group were identified as eligible for final analysis. Compared with traditional therapy, SLIT add-on therapy was associated with significant improvements in lower and upper airway scores, a higher forced expiratory volume in 1 second, and maximal expiratory flow at 25% of forced vital capacity, and improved bronchial reactivity. Drug consumptions were significantly decreased as well. Airway inflammatory parameters, such as nasal eosinophil infiltration, were markedly improved.

CONCLUSION

The findings of this study suggested that long-term SLIT add-on therapy is a complementary treatment for adults with asthma in addition to conventional medicine. It not only reduces symptom scores but also improves lung function and airway inflammation.

Immunotherapy: Treating with Fewer Allergens?

Polysensitization, sensitization to more than one allergen, is a common feature of patients with allergic rhinitis, and may be a risk factor for subsequent development of allergic diseases, especially allergic asthma. However, a polysensitized patient does not necessarily have polyallergy, a documented, causal relationship between exposure to 2 or more specific, sensitizing allergens and the subsequent occurrence of relevant clinical symptoms of allergy. Allergen immunotherapy treatment strategy for the polysensitized patient in Europe is to treat the single or 2 most clinically relevant allergen(s), whereas patients in the United States are usually treated for all potential clinically relevant allergens.

Effectiveness of regionally-specific immunotherapy for the management of canine atopic dermatitis

Background

Canine atopic dermatitis is a common pruritic skin disease often treated with allergen immunotherapy (AIT). AIT in dogs traditionally begins with attempting to identify clinically relevant environmental allergens. Current allergen testing methodologies and immunotherapy techniques in dogs are not standardized. Immunotherapy with a mixture of allergenic extracts selected based on regional aerobiology rather than intradermal tests or serum IgE assays has been described. The objective of this study was to evaluate the effectiveness of regionally-specific immunotherapy in dogs with atopic dermatitis. The medical records of a veterinary dermatology referral clinic were searched for dogs with atopic dermatitis that began regionally-specific subcutaneous immunotherapy from June, 2010 to May, 2013. An overall assessment of treatment effectiveness (excellent, good, fair, or poor) was assigned based upon changes in pruritus severity, lesion severity, and the reduction in concurrent medication(s) during a follow-up period of at least 270 days. Baseline characteristics that might predict treatment success were analyzed with the Spearman’s correlation and the Kruskal-Wallis tests.

Results

Of the 286 dogs that began regionally-specific immunotherapy (RESPIT) during a 3 year period, 103 met the inclusion criteria. The overall response to RESPIT was classified as excellent in 19%, good in 38%, fair in 25%, and poor in 18% of dogs. The response classification correlated significantly with a reduction in pruritus severity (r = 0.72, p < 0.001) and lesion severity (r = 0.54, p < 0.001), but not with the dogs’ baseline characteristics. Adverse reactions were reported in 7/286 (2.4%) of treated dogs.

Conclusions

Under the conditions of this study, RESPIT was safe and effective for the treatment of atopic dermatitis in dogs.

Current Evidence on Safety and Practical Considerations for Administration of Sublingual Allergen Immunotherapy (SLIT) in the United States

Liquid sublingual allergen immunotherapy (SLIT) has been used off-label for decades, and Food and Drug Administration (FDA)-approved grass and ragweed SLIT tablets have been available in the United States since 2014. Potentially life-threatening events from SLIT do occur, although they appear to be very rare, especially for FDA-approved products. Practice guidelines that incorporate safety precautions regarding the use of SLIT in the United States are needed. This clinical commentary attempts to address unresolved issues including controversy regarding the FDA mandate for the prescription of epinephrine autoinjectors for patients on SLIT; how to approach polysensitized patients; optimal timing and duration of SLIT administration; how to address gaps in therapy; whether antihistamines can prevent local reactions, if certain patient populations (such as persistent asthmatics) should not receive SLIT; and when to instruct patients to self-administer epinephrine. Key points are that physicians should focus on educating patients regarding: (1) when not to administer SLIT; (2) how to recognize a potentially serious allergic reaction to SLIT; and (3) when to administer epinephrine and seek emergency care.

Allergen immunotherapy (AIT) for the multiple-pollen sensitive patient

INTRODUCTION

The majority of allergic subjects are polysensitized. In Europe, allergy immunotherapy (AIT) in these patients is usually limited to their single clinically most troublesome allergy while in the U.S. the immunotherapy prescription usually includes all allergen extracts to which the patient has evidence of clinical sensitivity. Areas covered: This article will review the evidence supporting the U.S. practice. It will also review the major new development in the management of polysensitized patients, the introduction of component-resolved diagnosis (CRD). Expert commentary: This allows, in many cases, distinguishing in polysensitized patients between sensitization to the major allergens of several unrelated allergen extracts and to panallergens that cause broad patterns of cross-reactivity.

Subcutaneous Immunotherapy and Sublingual Immunotherapy: Comparative Efficacy, Current and Potential Indications, and Warnings--United States Versus Europe

Subcutaneous immunotherapy and sublingual immunotherapy are effective for allergic rhinitis and allergic asthma and with some support for use in selected patients with atopic dermatitis. The sequence of immunologic responses is the same, irrespective of the route of administration, and similar disease modification has been demonstrated. However, there are differences between the two approaches. The most important is the greatly reduced likelihood of sublingual immunotherapy producing systemic reactions. There are major drawbacks for sublingual immunotherapy in regard to dosing. Finally, there is the question of relative clinical efficacy, with the currently available data favoring subcutaneous immunotherapy.

Patient selection for subcutaneous versus sublingual immunotherapy

PURPOSE OF REVIEW

With the Food and Drug Administration's approval of sublingual allergen-specific immunotherapy (SL-AIT) tablets for grass and ragweed pollen, SL-AIT is progressively gathering importance not only in Europe, but also in the United States and other parts of the world. We reviewed issues related to the selection of patients for the sublingual or the subcutaneous route for allergic patients, based on what has been published since January 2014 on subcutaneous-versus-SL-AIT efficacy, safety and other issues. (Figure is included in full-text article.)

RECENT FINDINGS

As patient's adherence seems one of the major problems in real-life AIT, investigators have sought how to enhance AIT simplicity by changing the route to home-administrated SL-AIT, and by shortening the subcutaneous-allergen-specific immunotherapy (SC-AIT) build-up or maintenance phase. The latter was safe with several hypoallergenic extracts. As for SL-AIT, double blind placebo-controlled large trials in patients with allergic rhinitis and asthma have shown the efficacy and safety of ragweed pollen and house dust mite SLIT tablets and highly concentrated liquid formulations, primarily in adults. A large trial with SLIT in 3-year-old children was effective.

SUMMARY

With the improvement of SL-AIT efficacy, the selection of SC-versus-SL-AIT will probably increasingly be based not on efficacy, but on practical aspects, without losing sight of which SL-AIT products have proven efficacy.

Sublingual Immunotherapy: A Useful Tool for the Allergist in Private Practice

This is a review of the author's experience with Sublingual Immunotherapy in a private office setting. Sublingual Immunotherapy should be considered by any allergy practitioner as a useful tool. Sublingual Immunotherapy is safe while at the same time it is effective. It enables the practitioner to treat asthmatics and young children without the concerns implicit with allergy injections.

Optimum treatment strategies for polyallergic patients - analysis of a large observational trial

OBJECTIVES

To document the effectiveness and safety of sublingual allergen immunotherapy (SLIT) with a five-grass pollen tablet (Oralair ) and compare different treatment options in a broad, non-selected population of patients in a real-world clinical setting.

RESEARCH DESIGN AND METHODS

This was a 2 year, open, prospective, multicenter, single-arm, non-interventional study. Patients with a history of clinically relevant allergic symptoms caused by grass pollen, confirmed by skin prick testing, received treatment with the five-grass pollen tablet. Concomitant treatment with symptomatic medication and/or additional SLIT or subcutaneous immunotherapy (SCIT) was permitted. Twelve-month data are presented here. Effectiveness was assessed comparing a combined rhinoconjunctivitis (RC) score derived from the severity of rhinitis and conjunctivitis symptoms under treatment with retrospective data of the previous year.

RESULTS

A total of 1408 patients participated in the study, of whom 434 were children/adolescents and 962 polyallergic. Compared with the grass pollen season preceding five-grass pollen tablet treatment, a statistically significant reduction of 49.9% was achieved in RC score for the total population (p < 0.001), and an improvement in overall health was perceived by 90.9% of patients. The overall population of polyallergic patients derived similar benefits from treatment with the five-grass pollen tablet as monoallergic patients. The percentage reduction in RC score was larger in polyallergic patients taking no additional therapy (60.2%) than in those taking concomitant symptomatic medication (38.1%) or allergen immunotherapy (AIT) (50.8%). Within the last of these groups, RC score improved by 47.6% among patients receiving additional SCIT, versus 54.8% with additional SLIT. Adverse drug reactions, reported in 15.3% of study participants, were mostly local in nature and mild or moderate in intensity.

CONCLUSIONS

After 1 year of treatment, polyallergic patients responded similarly to the five-grass pollen tablet as monoallergic patients. For polyallergic patients in whom additional treatment was needed, a second SLIT may be more beneficial than a SCIT or symptomatic co-medication.

Management of polysensitized patient: from molecular diagnostics to biomolecular immunotherapy

A panel of Italian allergists gathered to discuss the issue concerning the management of polysensitized patients. The main conclusions were as follows: polysensitization is a relevant clinical characteristic as it affects about 70-80% of the global allergic population; the diagnostic pathway needs the use of an adequate and thorough methodology, based on the demonstration of consistency between history and documented sensitization; polysensitization and polyallergy are not synonymous: true allergy should always be demonstrated; polysensitization does not constitute a limitation to allergen immunotherapy prescription, as 1-2 allergen extracts could be effective in polysensitized patients; the allergen immunotherapy product characteristics should include the following: high efficacy and optimal safety profile, standardized production, and documented presence and titration of the major allergen.

Selection of patients for sublingual versus subcutaneous immunotherapy

Allergen immunotherapy is the sole treatment for IgE-mediated allergic diseases directed at the underlying mechanism. The two widely accepted administration routes are sublingual (SLIT) and subcutaneous (SCIT). We reviewed how patients should best be selected for immunotherapy and how the optimal administration route can be defined. Before deciding SCIT or SLIT, appropriate selection of patients for allergen immunotherapy (AIT) is mandatory. To be eligible for AIT, subjects must have a clear medical history of allergic disease, with exacerbation of symptoms on exposure to one or more allergens and a corresponding positive skin or in vitro test. Then the route of administration should be based on: published evidence of clinical and immunologic efficacy (which varies per allergic disease and per allergen); mono- or multi-allergen immunotherapy, for SLIT multi-allergen immunotherapy was not effective; safety: adverse events with SLIT are more frequent, but less severe; and, costs and patient preferences, closely related to adherence issues. All these are discussed in the article.

Dosing of sublingual immunotherapy for allergic rhinitis: evidence-based review with recommendations

BACKGROUND

Since the mid 1980s, the clinical use of sublingual immunotherapy (SLIT) has dramatically increased. However, 1 of the primary barriers to providing SLIT is lack of a published dosing recommendations. The purpose of this work is to provide a range of effective SLIT dosing based upon a rigorous review of the existing evidence base. An appendix with SLIT dosing recommendations is also included.

METHODS

A comprehensive search of the past 25 years of the medical literature using PubMed was performed for specific antigens. Inclusion criteria for articles included: randomized, placebo-controlled studies of SLIT, studies with clinical allergic rhinitis outcomes, and dosing units available to determine the micrograms per month of major allergen administered. The extracted data was used to compile a range of effective SLIT dosing for individual antigens.

RESULTS

Seventy-five articles met the inclusion criteria, providing a range of effective dosing for some allergens. There was commonly a wide range in doses for particular antigens between the individual studies. For some antigens, there was significant overlap in dosage amount between studies showing efficacy and lack of efficacy. Clinical trials meeting inclusion criteria are not available for many allergens.

CONCLUSION

This study provided a comprehensive review of the published sublingual dosing ranges for specific antigens. The review provided a range of effective sublingual doses for some allergens, whereas for other allergens there was insufficient published data to determine specific doses. Recommendations for SLIT dosing were produced based on the data revealed in the review and expert opinion.

Immunotherapy in all aspects

Allergen immunotherapy is a form of long-term treatment that decreases symptoms for many people with allergic rhinitis, allergic asthma, conjunctivitis (eye allergy) or stinging insect allergy. In this review, we presented the important topics in immunotherapy. The important aspects of immunotherapy are considered to be "Immunologıcal responses to immunotherapy"; "The principal types of immunotherapy"; "Effectiveness"; "Indications"; "Contraindications"; "Allergen immunotherapy in children"; "Safety"; and "Anaphylactic reactions after immunotherapy". The principal types of immunotherapy are subcutaneous immunotherapy (SCIT) and sublingual immunotherapy. Both of them can be used in indicated cases. When using SCIT, physicians must be more careful because of reported rare fatal cases. The risks and benefits of continuing allergen immunotherapy in patients who have experienced severe systemic reactions should be carefully considered.

Sublingual immunotherapy in allergic rhinitis: efficacy, safety, adherence and guidelines

Allergic rhinitis (AR) is a globally increasing health problem affecting the quality of life. Specific immunotherapy is an available causal treatment changing the basic allergic mechanisms of the disease. Over one hundred years, subcutaneous immunotherapy (SCIT) was developed and proved its efficacy but many adverse effects were recorded including anaphylaxis. In 1986, sublingual immunotherapy (SLIT) was introduced as an alternative solution to solve this problem. Our study aims to discuss SLIT from the points of efficacy, safety, adherence and guidelines developed. A literature search was conducted in Medline/PubMed and the Cochrane Library in January 2013 using the keywords "allergic rhinitis, sublingual immunotherapy, efficacy, safety, compliance, adherence, guidelines." All types of publications were included. We augmented our study by searching the reference lists of identified reviews. SLIT has been established in many guidelines as an evidence-based effective treatment in AR with safer profile than SCIT. The meta-analyses confirmed its efficacy and showed a significant reduction in both symptoms and medication scores. The most common recorded adverse effects were minor local effects in the mouth, gastrointestinal reactions with few cases of anaphylaxis and no fatality. Adherence is more favorable for SLIT mainly because it is safe, noninvasive and easily taken at home. We support the call to conduct large multi-centric studies to gain more statistical power and overcome the problem of heterogeneity observed in the meta-analyses.

Efficacy and safety of house dust mite sublingual immunotherapy in monosensitized and polysensitized children with respiratory allergic diseases

BACKGROUND

The efficacy of single-allergen-specific immunotherapy in polysensitized subjects is a matter of debate. This study aimed to investigate the efficacy of house dust mite (HDM) sublingual immunotherapy (SLIT) in monosensitized and polysensitized children.

METHODS

A total of 112 children, aged 4 to 13 years old, with HDM-induced respiratory allergic diseases were allocated to a monosensitized group (n = 56) or a polysensitized group (n = 56). Both groups were treated by standard pharmacotherapy and SLIT with Dermatophagoides farinae (American HDM) extracts for 52 weeks. Symptoms, medications, visual analogue scale (VAS), and presence of adverse events (AEs) were assessed once a month. Skin-prick test (SPT) was done before and after treatment. After treatment, subjects in the polysensitized group who completed the study were further analyzed as subgroup 1 (n = 20) and subgroup 2 (n = 15) according to the number of coexisting allergens.

RESULTS

Forty-one subjects in the monosensitized group and 35 subjects in the polysensitized group completed the study. The global clinical parameters had significantly improved after treatment, with no significant difference between the monosensitized and polysensitized group throughout this period (all p > 0.05). The comparison among the monosensitized group, subgroup 1, and subgroup 2 indicated that there was no significant difference in symptoms scores and VAS at each scheduled follow-up visit. There was also no significant difference in total medications score (TMS) in the monosensitized group, subgroup 1, and subgroup 2 after week 24 (all p > 0.05). No severe systemic AEs were reported.

CONCLUSION

No significant difference was observed in the clinical effects of HDM SLIT between polysensitized and monosensitized children with respiratory allergic diseases.

New developments in the treatment of pediatric allergic rhinitis and conjunctivitis

The primary care physician is the first line of treatment for allergic rhinitis, which affects approximately one-fourth of children in the United States. There is an increasing trend toward self-management by patients or parents due to high-deductible insurance plans and the over-the-counter availability of allergy medications. The primary care physician can offer guidance on appropriate selection of medications and potential adverse effects. Vitamin D deficiency has been proposed as a potential contributing factor in patients with allergic diseases, and studies are underway to determine whether supplementation with vitamin D is helpful for these conditions. Sublingual immunotherapy has recently received US Food and Drug Administration approval for grass and ragweed allergens; many children will be interested in this alternative to allergy shots. The relative advantages and disadvantages of sublingual vs subcutaneous immunotherapy are discussed.

Sublingual immunotherapy: the U.S. experience

PURPOSE OF REVIEW

It is likely that approval of allergen preparations for sublingual immunotherapy (SLIT) will soon occur in the United States. This article reviews experience with SLIT in this country, concentrating on the large, multicenter trials that will provide the evidence of safety and efficacy necessary to obtain that approval.

RECENT FINDINGS

Large multicenter trials have been conducted with both grass and short ragweed. In five single-season studies with sublingual grass tablets, usually starting 4 months prior to and continuing through the pollen season, the combined symptom medication score was improved 20-28% relative to placebo-treated individuals. Short ragweed tablets, initiated 4 months prior to and continued through the pollen season, reduced symptom/medication scores by 24-26%. Similar results have been reported with short ragweed aqueous extract administered sublingually. To date, there has been only one small study each with house dust mite and cat allergen extracts. All of these studies were conducted with a single allergen. One small study, comparing timothy alone to the same dose of timothy combined with nine other pollen extracts, raised still unanswered questions regarding the efficacy of SLIT with multiple allergen mixes.

SUMMARY

SLIT is coming to the United States. There will be approved allergen preparations for which the appropriate dosing for efficacy and safety has been established. It would be inappropriate to use the evidence generated by these large studies to justify off-label use of allergen extracts approved for injection or the administration of multiple allergen preparations sublingually.

Subcutaneous immunotherapy versus sublingual immunotherapy: which is more effective?

Subcutaneous immunotherapy (SCIT) and sublingual immunotherapy (SLIT) are both effective treatments for allergic rhinitis and allergic asthma, both show clinical evidence of disease modification by decreasing new sensitizations in individuals who were monosensitized, by reducing the development of asthma in patients with allergic rhinitis, and by inducing clinical improvement that persists for years after discontinuation of a successful course of treatment. Initiation of SLIT is accompanied by a high incidence of local symptoms, but these are generally mild and do not usually persist beyond the first few weeks. Systemic reactions do occasionally occur with SLIT but much less frequently than with SCIT, and, to date, no fatal or near fatal reactions have been reported. Effective doses have been defined for many allergens for SCIT and are now being defined for SLIT. There remains the unanswered question of the effectiveness of SLIT with multiple allergen extracts. The relative clinical efficacy of SCIT and SLIT remains to be defined. When each is compared with placebo, results of meta-analyses suggest greater efficacy of SCIT. In the limited number of randomized, head-to-head studies, SCIT has more often provided greater clinical and immunologic responses. However, head-to-head studies with well-defined effective doses by the 2 routes are urgently needed.

Sublingual immunotherapy: World Allergy Organization position paper 2013 update

We have prepared this document, "Sublingual Immunotherapy: World Allergy Organization Position Paper 2013 Update", according to the evidence-based criteria, revising and updating chapters of the originally published paper, "Sublingual Immunotherapy: World Allergy Organization Position Paper 2009", available at http://www.waojournal.org. Namely, these comprise: "Mechanisms of sublingual immunotherapy;" "Clinical efficacy of sublingual immunotherapy" - reporting all the data of all controlled trials published after 2009; "Safety of sublingual immunotherapy" - with the recently published Grading System for adverse reactions; "Impact of sublingual immunotherapy on the natural history of respiratory allergy" - with the relevant evidences published since 2009; "Efficacy of SLIT in children" - with detailed analysis of all the studies; "Definition of SLIT patient selection" - reporting the criteria for eligibility to sublingual immunotherapy; "The future of immunotherapy in the community care setting"; "Methodology of clinical trials according to the current scientific and regulatory standards"; and "Guideline development: from evidence-based medicine to patients' views" - including the evolution of the methods to make clinical recommendations.Additionally, we have added new chapters to cover a few emerging crucial topics: "Practical aspects of schedules and dosages and counseling for adherence" - which is crucial in clinical practice for all treatments; "Perspectives and new approaches" - including recombinant allergens, adjuvants, modified allergens, and the concept of validity of the single products. Furthermore, "Raising public awareness about sublingual immunotherapy", as a need for our patients, and strategies to increase awareness of allergen immunotherapy (AIT) among patients, the medical community, all healthcare stakeholders, and public opinion, are also reported in detail.

Recombinant house dust mite allergens

House dust mites (HDM) are a globally important source of allergen responsible for the sensitization of more than 50% of allergic patients. Specific immunotherapy with HDM extracts is effective but allergen extracts cannot be fully standardized and severe side-effects can occur during the protracted course of treatment. The introduction of molecular biological techniques into allergy research allowed the indentification of more than 20 groups of HDM allergens. Recombinant HDM allergens can be produced in defined concentrations and consistent quality and allow the development of vaccines for HDM allergy with reduced allergenic activity and retained immunogenicity. The immunotherapy trials in pollen allergic patients with recombinant pollen allergens/hypoallergenic allergen derivatives have shown that this treatment is effective and indicated that recombinant HDM vaccines might improve immunotherapy of HDM allergic patients. Here we report the steps for the development of vaccines for HDM allergy. After selection of the most prevalent HDM species, the panel of allergens to be included into a therapeutic vaccine for HDM allergy needs to be determined. HDM allergens with high IgE-binding frequency and clinical relevance will be modified into hypoallergenic variants and evaluated for their allergenic activity and immunogenicity. Derivatives with reduced allergenic activity but with retained immunogenicity would be good candidates for a HDM vaccine for safe and efficient immunotherapy.

Agreement between allergen-specific IgE assays and ensuing immunotherapy recommendations from four commercial laboratories in the USA

BACKGROUND

Canine allergen-specific IgE assays in the USA are not subjected to an independent laboratory reliability monitoring programme.

HYPOTHESIS/OBJECTIVES

The aim of this study was to evaluate the agreement of diagnostic results and treatment recommendations of four serum IgE assays commercially available in the USA.

METHODS

Replicate serum samples from 10 atopic dogs were submitted to each of four laboratories for allergen-specific IgE assays (ACTT(®) , VARL Liquid Gold, ALLERCEPT(®) and Greer(®) Aller-g-complete(®) ). The interlaboratory agreement of standard, regional panels and ensuing treatment recommendations were analysed with the kappa statistic (κ) to account for agreement that might occur merely by chance. Six comparisons of pairs of laboratories and overall agreement among laboratories were analysed for ungrouped allergens (as tested) and also with allergens grouped according to reported cross-reactivity and taxonomy.

RESULTS

The overall chance-corrected agreement of the positive/negative test results for ungrouped and grouped allergens was slight (κ = 0.14 and 0.13, respectively). Subset analysis of the laboratory pair with the highest level of diagnostic agreement (κ = 0.36) found slight agreement (κ = 0.13) for ungrouped plants and fungi, but substantial agreement (κ = 0.71) for ungrouped mites. The overall agreement of the treatment recommendations was slight (κ = 0.11). Altogether, 85.1% of ungrouped allergen treatment recommendations were unique to one laboratory or another.

CONCLUSIONS AND CLINICAL IMPORTANCE

Our study indicated that the choice of IgE assay may have a major influence on the positive/negative results and ensuing treatment recommendations.

Modulation of mucosal/systemic antibody response after sublingual immunotherapy in mite-allergic children

BACKGROUND

There have been no data on sublingual immunotherapy (SLIT) in Brazilian patients sensitized to house dust mites. This study aimed to evaluate the mucosal/systemic antibody response changes and clinical efficacy after SLIT using Dermatophagoides pteronyssinus (Dpt) allergens with or without bacterial extracts in mite-allergic Brazilian children.

METHODS

Patients with allergic rhinitis and asthma were selected for a double-blind, placebo-controlled trial randomized to three groups: DPT (Dpt extract, n = 34), DPT+MRB (Dpt plus mixed respiratory bacterial extracts, n = 36), and Placebo (n = 32). Total symptom and medication scores for rhinitis/asthma, skin prick test (SPT) to Dpt, and measurements of Dpt-, Der p 1-, Der p 2-specific serum IgE, IgG4, IgG1, and specific salivary IgA were evaluated at baseline and after 12 and 18 months of treatment.

RESULTS

A significant long-term decline in total symptom/medication scores was observed only in active groups (DTP and DPT+MRB). There was no significant change in SPT results in all groups. SLIT using Dpt allergen alone induced increased levels of serum IgG4 to Dpt, Der p 1, and Der p 2, serum IgG1 and salivary IgA to Dpt and Der p 1. SLIT with Dpt plus bacterial extracts was able to decrease IgE levels, particularly to Der p 2, to increase salivary IgA levels to Der p 1, but had no changes on specific IgG4 and IgG1 levels.

CONCLUSIONS

All children undergoing SLIT showed clinical improvement, but a long-term reduction in symptom/medication scores with modulation of mucosal/systemic antibody responses were seen only in active groups (DPT and DPT+MRB).