Safety profile and immunological response of dual sublingual immunotherapy with house dust mite tablet and Japanese cedar pollen tablet

Investigating Experimental Treatments for Rhinitis: A State-of-the-Art Systematic Review

Background: Rhinitis is a common inflammatory condition that affects the nasal passages, significantly impacting quality of life and placing a considerable burden on healthcare systems. While traditional treatments offer limited relief, there is a growing interest in novel therapies. This systematic review aims to analyze investigational new treatments for rhinitis. Methods: A search was conducted in ClinicalTrials.gov, the World Health Organization International Clinical Trials Registry Platform, and the European Union Clinical Trials Register, as well as PubMed, Web of Science, and the Cochrane Library. Both ongoing and completed clinical trials exploring innovative therapies for rhinitis, including immunotherapy, probiotics, and stem cell therapy, were included. Results: This systematic review compiled information from 74 clinical trials-51 completed and 23 ongoing-focused on new treatments for rhinitis. A significant portion of the completed studies (44) focused on various forms of immunotherapy, which showed potential for long-term effectiveness and had a high safety profile. Another seven completed trials investigated probiotics as a treatment method, yielding mixed results, though they did show promise in managing symptoms, particularly when combined with other treatments. The ongoing trials are primarily investigating immunotherapy, with a smaller number looking at probiotics and stem cell therapy. This shows a continued exploration of innovative and diverse therapies for managing rhinitis. Conclusion: This study highlights the potential of emerging rhinitis therapies to improve patient outcomes and enhance quality of life. Continued research is recommended for developing more effective, personalized, and targeted therapeutic strategies for rhinitis.

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.

The Art of Dosing for Subcutaneous Immunotherapy in North America

Subcutaneous immunotherapy (SCIT) is a long-established treatment option for allergic rhinoconjunctivitis. Proper dosing of the allergens is critical for the efficacy and safety of SCIT. Of the hundreds of liquid allergen extracts in the United States, effective and well-tolerated SCIT dosing has only been established for a small number. Thus, SCIT dosing remains largely empiric and continues to be, by necessity, an art. To highlight the complexity of SCIT dosing, this review summarizes the historical and current landscape of U.S. allergen extracts, differences among U.S. and European allergen extracts, allergen selection for SCIT, considerations for compounding of allergen extract mixtures, and recommended dosing. As of 2021, 18 standardized allergen extracts are available in the United States; all other extracts remain unstandardized without characterization of allergen content or potency. U.S. allergen extracts differ from European extracts in formulation and potency characterization. There is no standardized methodology for SCIT allergen selection, and interpretation of allergen sensitization is not straightforward. Compounding of SCIT mixtures requires consideration of potential dilution effects, allergen cross-reactivity, proteolytic activity, and additives. Probable effective dose ranges for SCIT are recommended in U.S. allergy immunotherapy practice parameters, although there are few studies using U.S. extracts supporting these doses as therapeutic. In contrast, optimized doses of sublingual immunotherapy tablets have been confirmed in North American phase 3 trials. The SCIT dosing for each patient remains an art that requires clinical experience and consideration of polysensitization, tolerability, compounding of allergen extract mixtures, and the range of recommended doses within the context of extract potency variability.

Increase in the prevalence of follicular regulatory T cells correlates with clinical efficacy of sublingual immunotherapy with house dust mites

BACKGROUND

Allergic rhinitis (AR) impairs quality of life and affects nearly 40% of the Japanese population. Sublingual immunotherapy (SLIT) is the disease-modifying treatment for AR, but requires the selection of a biomarker associate with clinical efficacy in patients with AR who are treated with SLIT. The present study sought to examine objective biomarkers used for assessing the clinical efficacy of SLIT.

METHODS

The authors examined the effects of 1 year of SLIT treatment with house dust mites (HDMs) using peripheral blood mononuclear cells (PBMCs) and serum from patients with AR. The prevalences of follicular regulatory T (Tfr), type 2 follicular helper T (Tfh2), type 2 helper T (Th2), conventional regulatory T (Treg), and type 1 regulatory T (Tr1) cells were examined by flow cytometry. Serum concentrations of HDM-specific IgA, IgE, and IgG4 antibodies, and HDM-induced production of interleukin (IL) 5 and IL-10 from cultured PBMCs were evaluated by enzyme-linked immunosorbent assay.

RESULTS

Following 1 year of SLIT, the prevalences of Tfr, conventional Treg, and Tr1 cells were significantly increased, whereas that of Th2 cells and Tfh2 cells were significantly decreased; the serum concentration of HDM-specific IgG4 was significantly increased; and HDM-induced production of IL-5 from PBMCs was significantly decreased, while that of IL-10 was significantly increased. The increase in the prevalence of Tfr cells after SLIT correlated positively with the improvement of clinical symptom scores.

CONCLUSION

An increase in Tfr cells may play an important role in SLIT, and may be a useful indicator for the clinical efficacy of SLIT.

A practical guide to prescribing sublingual immunotherapy tablets in North America for pediatric allergic rhinoconjunctivitis: an injection-free allergy immunotherapy option

Allergic rhinoconjunctivitis (ARC) is a common disease that affects individuals of all ages. Pediatricians may be the first (and only) point of care for children with ARC. Sublingual immunotherapy (SLIT)-tablets are a convenient at-home, injection-free allergy immunotherapy option that can be used for the treatment of ARC. This paper provides a practical guide for pediatricians to aid in prescribing SLIT-tablets to children with ARC in North America. Topics include a summary of the available SLIT-tablets and their efficacy and safety, guidance on when SLIT-tablets are an appropriate option, and how to diagnose ARC and identify culprit allergens. Practical guidance is also provided through a proposed decision tree, a prescribing checklist and prescribing procedures, and suggested follow-up assessments.

International consensus statement on allergy and rhinology: Allergic rhinitis - 2023

BACKGROUND

In the 5 years that have passed since the publication of the 2018 International Consensus Statement on Allergy and Rhinology: Allergic Rhinitis (ICAR-Allergic Rhinitis 2018), the literature has expanded substantially. The ICAR-Allergic Rhinitis 2023 update presents 144 individual topics on allergic rhinitis (AR), expanded by over 40 topics from the 2018 document. Originally presented topics from 2018 have also been reviewed and updated. The executive summary highlights key evidence-based findings and recommendation from the full document.

METHODS

ICAR-Allergic Rhinitis 2023 employed established evidence-based review with recommendation (EBRR) methodology to individually evaluate each topic. Stepwise iterative peer review and consensus was performed for each topic. The final document was then collated and includes the results of this work.

RESULTS

ICAR-Allergic Rhinitis 2023 includes 10 major content areas and 144 individual topics related to AR. For a substantial proportion of topics included, an aggregate grade of evidence is presented, which is determined by collating the levels of evidence for each available study identified in the literature. For topics in which a diagnostic or therapeutic intervention is considered, a recommendation summary is presented, which considers the aggregate grade of evidence, benefit, harm, and cost.

CONCLUSION

The ICAR-Allergic Rhinitis 2023 update provides a comprehensive evaluation of AR and the currently available evidence. It is this evidence that contributes to our current knowledge base and recommendations for patient evaluation and treatment.

Minimization of ragweed allergy immunotherapy costs through use of the sublingual immunotherapy tablet in Canadian children with allergic rhinoconjunctivitis

BACKGROUND

Allergy immunotherapy (AIT), in the form of subcutaneous immunotherapy (SCIT) with alum-precipitated aqueous extracts, SCIT with a modified ragweed pollen allergen tyrosine adsorbate (MRPATA; Pollinex^®-R), or a sublingual immunotherapy (SLIT)-tablet are options for the treatment of ragweed pollen allergic rhinoconjunctivitis (ARC) in Canadian children. A cost minimization analysis evaluated the economic implications of the use of the ragweed SLIT-tablet vs SCIT in Canadian children with ragweed ARC.

METHODS

A cost minimization analysis was conducted comparing the short ragweed SLIT-tablet, 12 Amb a 1-U, preseasonally with preseasonal ragweed SCIT, annual ragweed SCIT, or MRPATA. The analysis was conducted over a time horizon of 3 years from a public payer perspective in Ontario and Quebec. Resources and costs associated with medication and services of healthcare professionals were considered for each treatment. The resource and cost input values for the model were obtained from published literature and validated by Canadian clinical experts in active allergy practice. A discount rate of 1.5% was applied. Several scenario analyses were conducted to determine the impact of many of the key base case assumptions on the outcomes.

RESULTS

Over the total 3-year time horizon, the ragweed SLIT-tablet had a potential cost savings of $900.14 in Ontario and $1023.14 in Quebec when compared with preseasonal ragweed SCIT, of $6613.22 in Ontario and $8750.64 in Quebec when compared with annual ragweed SCIT, and $79.62 in Ontario and $429.49 in Quebec when compared with MRPATA. The ragweed SLIT-tablet had higher drug costs compared with the other AIT options, but lower costs for healthcare professional services. The lower costs for healthcare professional services with the ragweed SLIT-tablet were driven by the need for fewer office visits than SCIT. Scenario analysis indicated that costs were most impacted by including societal costs (e.g., costs associated with patient/caregiver travel and time lost). The potential cost savings of the ragweed SLIT-tablet versus SCIT and MRPATA was maintained in most scenarios.

CONCLUSIONS

In this cost minimization analysis, the ragweed SLIT-tablet provided estimated cost savings from a public payer perspective for the treatment of ragweed ARC in Canadian children compared with SCIT or MRPATA.

Executive summary: Japanese guidelines for allergic rhinitis 2020

The Practical Guideline for the Management of Allergic Rhinitis, the fist guideline for allergic rhinitis in Japan, was prepared after a symposium held by the Japanese Society of Allergology in 1993. The current 9th edition was published in 2020 and is widely used today. The most recent collection of evidence from the literature was supplemented to the revised guideline to incorporate evidence-based medicine. The revised guideline includes updated epidemiology of allergic rhinitis in Japan, a figure representing the mechanisms of allergic rhinitis in both the onset and sensitization phases with the introduction of regulatory T cells and type 2 innate lymphoid cells, practical assessment for diagnosis, new pharmacotherapy agents such as anti-IgE mAb and a new drug delivery system for antihistamines, sublingual immunotherapy for children, dual sublingual immunotherapy for house dust mites and Japanese cedar pollen extract, new classification for surgery for allergic rhinitis, and treatment and prescriptions for older adults. An evidence-based step-by-step strategy for treatment is also described.

Update on pathomechanisms and treatments in allergic rhinitis

Allergic rhinitis (AR) is a global health problem with increasing prevalence and association with an enormous medical and socioeconomic burden. New recognition of immune cells such as type 2 innate lymphocytes (ILC2s), T helper (Th2) 2 cells, follicular helper T cells, follicular regulatory T cells, regulatory T cells, B cells, dendritic cells, and epithelial cells in AR pathogenesis has been updated in this review paper. An in-depth understanding of the mechanisms underlying AR will aid the identification of biomarkers associated with disease and ultimately provide valuable parameters critical to guide personalized targeted therapy. As the only etiological treatment option for AR, allergen-specific immunotherapy (AIT) has attracted increasing attention, with evidence for effectiveness of AIT recently demonstrated in several randomized controlled trials and long-term real-life studies. The exploration of biologics as therapeutic options has only involved anti-IgE and anti-type 2 inflammatory agents; however, the cost-effectiveness of these agents remains to be elucidated precisely. In the midst of the currently on-going COVID-19 pandemic, a global life-threatening disease, although some studies have indicated that AR is not a risk factor for severity and mortality of COVID-19, this needs to be confirmed in multi-centre, real-life studies of AR patients from different parts of the world.

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.

Japanese cedar and cypress pollinosis updated: New allergens, cross-reactivity, and treatment

Pollen from many tree species in the Cupressaceae family is a well-known cause of seasonal allergic diseases worldwide. Japanese cedar pollinosis and Japanese cypress pollinosis, which are caused by pollen from Japanese cedar (Cryptomeria japonica) and Japanese cypress (Chamaecyparis obtusa), respectively, are the most prevalent seasonal allergic diseases in Japan. Recently, the novel major Japanese cypress allergen Cha o 3 and the homologous Japanese cedar allergen Cry j cellulase were identified, and it was shown, for the first time, that cellulase in plants is allergenic. Although the allergenic components of pollen from both species exhibit high amino acid sequence identity, their pollinosis responded differently to allergen-specific immunotherapy (ASIT) using a standardized extract of Japanese cedar pollen. Pharmacotherapy and ASIT for Japanese cedar and cypress pollinosis have advanced considerably in recent years. In particular, Japanese cedar ASIT has entered a new phase, primarily in response to the generation of updated efficacy data and the development of new formulations. In this review, we focus on both Japanese cypress and cedar pollinosis, and discuss the latest findings, newly identified causative allergens, and new treatments. To manage pollinosis symptoms during spring effectively, ASIT for both Japanese cedar and Japanese cypress pollen is considered necessary.

Recent development on the use of sublingual immunotherapy tablets for allergic rhinitis

OBJECTIVE

Allergic rhinitis (AR) is an immunoglobulin (Ig) E-mediated inflammatory condition that causes sneezing, nasal congestion, rhinorrhea, and nasal itch. Although subcutaneous immunotherapy for the treatment of AR has been in use and well established as a treatment modality, sublingual immunotherapy (SLIT) is increasingly considered to be the safer and more convenient alternative. Thus, the objective of this review is to describe recent findings pertaining to the use of SLIT tablets (SLIT-T) for AR.

DATA SOURCES

A database search (PubMed.gov) for articles published between January 1, 2017, and February 9, 2021, was conducted using the following key words: "allergic rhinitis," AND-ed "sublingual immunotherapy." Included were randomized placebo-controlled trials. Other experimental design studies were excluded.

STUDY SELECTIONS

A total of 11 randomized placebo-controlled trials were selected for full-text review and included in the analysis. All studies investigated the use of SLIT on patients with seasonal AR (4 tree pollen, 1 grass pollen, and 1 Japanese cedar) or perennial AR (3 house dust mite).

RESULTS

Our review of 7 recently published randomized placebo-controlled trials with 2348 subjects receiving SLIT reported increased efficacy, safety, supportive immunologic parameters (IgE and IgG4 pre- and posttreatment levels), and improved quality of life. All studies excluded subjects with overlapping seasonal or perennial allergens, a history of moderate-to-severe uncontrolled asthma, or reduced lung function.

CONCLUSION

Our review highlights that SLIT is a safe and effective treatment that considerably reduces symptoms and medication requirements in AR and improves quality of life.

Sublingual Immunotherapy: How Sublingual Allergen Administration Heals Allergic Diseases; Current Perspective about the Mode of Action

Owing to the successful application of sublingual immunotherapy (SLIT), allergen immunotherapy (AIT) has become one of the leading treatments for allergic diseases. Similar to the case with other AITs, such as subcutaneous and oral immunotherapies, not only the alleviation of allergic symptoms, but also the curing of the diseases can be expected in patients undergoing SLIT. However, how and why such strong efficacy is obtained by SLIT, in which allergens are simply administered under the tongue, is not clearly known. Various potential mechanisms, including the induction of blocking antibodies, T cell tolerance, regulatory B and T cells, CD103^-CD11b⁺ classical dendritic cells, and CD206⁺ macrophages, and the reduction of innate lymphoid cells, mast cells, and basophils, have been suggested. Recently, through a comparative analysis between high- and non-responder patients of SLIT, we have successfully proposed several novel mechanisms. Here, we introduce our recent findings and summarize the current understanding of the mechanisms underlying the strong efficacy of SLIT.

Mechanisms of allergen-specific immunotherapy and allergen tolerance

Allergen-specific immunotherapy (AIT) is the mainstay treatment for the cure of allergic disorders, with depicted efficacy and safety by several trials and meta-analysis. AIT impressively contributes to the management of allergic rhinitis, asthma and venom allergies. Food allergy is a new arena for AIT with promising results, especially via novel administration routes. Cell subsets with regulatory capacities are induced during AIT. IL-10 and transforming growth factor (TGF)-β are the main suppressor cytokines, in addition to surface molecules such as cytotoxic T-lymphocyte-associated antigen-4 (CTLA-4) and programmed cell death protein-1 (PD-1) within the micro milieu. Modified T- and B-cell responses and antibody isotypes, increased activity thresholds for eosinophils, basophils and mast cells and consequent limitation of inflammatory cascades altogether induce and maintain a state of sustained allergen-specific unresponsiveness. Established tolerance is reflected into the clinical perspectives as improvement of allergy symptoms together with reduced medication requirements and evolved disease severity. Long treatment durations, costs, reduced patient compliance and risk of severe, even life-threatening adverse reactions during treatment stand as major limiting factors for AIT. By development of purified non-allergenic, highly-immunogenic modified allergen extracts, and combinational usage of them with novel adjuvant molecules via new routes may shorten treatment durations and possibly reduce these drawbacks. AIT is the best model for custom-tailored therapy of allergic disorders. Better characterization of disease endotypes, definition of specific biomarkers for diagnosis and therapy follow-up, as well as precision medicine approaches may further contribute to success of AIT in management of allergic disorders.

Clinical Practice of Allergen Immunotherapy for Allergic Rhinoconjunctivitis and Asthma: An Expert Panel Report

Allergen immunotherapy (AIT) reduces symptoms and medication use associated with allergic rhinitis with or without conjunctivitis and allergic asthma. Although several AIT guidelines exist, there remain unanswered questions about AIT that are relevant to everyday practice. Our objective was to prepare an evidence-based overview addressing the practical aspects of AIT in clinical practice based on published evidence and the experience of international experts in the field. Topics covered include interpretation and translation of clinical trial data into everyday clinical practice (eg, allergen doses and treatment duration), assessment of risk and treatment of local and systemic allergic reactions, recommendations for improvement of AIT guidelines, and identification of appropriate data for seeking regulatory approval, to name a few. Many informational gaps in AIT practice need further evaluation as products and practices evolve.

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.