SQ house dust mite sublingual immunotherapy tablet subgroup efficacy and local application site reaction duration

Focused allergic rhinitis practice parameter for Canada

Allergic rhinitis (AR) is a prevalent disease in Canada that affects both children and adults. Several guidelines for the management of AR have been published by professional allergy societies worldwide. However, there are regional differences in the clinical management of AR, and regulatory approval of some AR pharmacotherapies varies among countries. Thus, six research questions specific to the treatment of AR in Canada were identified for this focused practice parameter. Reviews of the literature published since 2016 were conducted to obtain evidence-based support for the responses of the Work Group to each research question. In response to research question 1 "In patients with symptoms indicative of AR, is serum-specific IgE sufficient to identify candidates for immunotherapy or is a skin prick test mandatory?" the Work Group concluded that either sIgE testing or skin prick test are acceptable for diagnosing AR and guiding immunotherapy. In response to research question 2 "When taking into account the preferences of the patient and the prescriber (stakeholder engagement) should second-generation oral antihistamine (OAH) or intranasal corticosteroid (INCS) be first line?" the Work Group concluded that existing guidelines generally agree on the use of INCS as a first-line therapy used for AR, however, patient and provider preferences and considerations can easily shift the first choice to a second-generation OAH. In response to research question 3 "Is a combination intranasal antihistamine (INAH)/INCS formulation superior to INCS plus OAH? Do they become equivalent after prolonged use?" the Work Group concluded that that the combination INAH/INCS is superior to an INCS plus OAH. However, there was insufficient evidence to answer the second question. In response to research question 4 "Do leukotriene receptor antagonists (LTRA) have a greater benefit than OAH in AR for some symptoms to justify a therapeutic trial in those who cannot tolerate INCS?" the Work Group concluded that LTRAs have inferior, or at best equivalent, daytime or overall symptom control compared with OAH, but LTRAs may improve nighttime symptom control and provide benefits in patients with AR and concomitant asthma. In response to research question 5 "Should sublingual immunotherapy (SLIT) tablets be considered first-line immunotherapeutic options over subcutaneous immunotherapy (SCIT) based on the evidence of efficacy?" the Work Group concluded that the choice of SLIT or SCIT cannot be made on efficacy alone, and differences in other factors outweigh any differences in efficacy. In response to research question 6 "Based on efficacy data, should ALL patients seen by an allergist be offered SLIT or SCIT as a treatment option?" the Work Group concluded that the efficacy data suggests that SLIT or SCIT should be used broadly in patients with AR, but other clinical concerns also need to be taken into consideration.

The evidence for commercial house dust mite immunotherapy products: A pragmatic systematic review with narrative synthesis

House dust mite (HDM) allergen immunotherapy (AIT) has an established role in the treatment of perennial allergic rhinitis (AR) and allergic asthma (AA) triggered by HDM sensitization. We aimed to identify all double-blind, randomized, placebo-controlled trials of HDM AIT for the treatment of AR and AA in humans and to summarize the evidence for AIT products that are currently manufactured and available for clinical use. A total of 56 eligible double-blind, randomized, placebo-controlled trials of HDM AIT for the treatment of AA and/or AR in humans fit the inclusion criteria and investigated a total of 14 commercial AIT products; together, the 56 studies enrolled a total of 14,619 patients. Of the 56 studies, 39 studies investigated the current manufacturer-recommended maintenance dose (MRMD) of the product, and 17 investigated other doses. We identified 39 studies (12,539 patients randomized) for 8 sublingual immunotherapy (SLIT) products and 17 studies (2,080 patients randomized) for subcutaneous immunotherapy products. For AR, 3 products, the ALK 12 standardized-quality (SQ-HDM) SLIT tablet, the ALK 6 SQ-HDM tablet, and the SG 300 index of reactivity SLIT tablet, had both dose-finding studies (DFSs) and phase III definitive studies (DSs) to demonstrate efficacy of the MRMD of the product. For AA, 2 products, the ALK 12 SQ-HDM SLIT tablet and the ALK 6 SQ-HDM tablet, had both DFSs and DSs for the MRMD. No subcutaneous immunotherapy product had a paired DFS and DS supporting the MRMD. A total of 30 studies of products no longer commercially manufactured were excluded. This study will help to inform clinical care and product selection for the treatment of HDM-induced AR and AA.

Safety of 300IR house dust mite sublingual tablet from pooled clinical trial and post-marketing data

Background

The 300IR house dust mite (HDM) sublingual immunotherapy (SLIT) tablet is approved for treatment of HDM-induced allergic rhinitis (AR). To provide a comprehensive review of the 300IR HDM-SLIT tablet safety profile based on randomized controlled trial (RCT) pooled data and post-marketing (PM) pharmacovigilance data.

Methods

Subjects (5-65 years) with confirmed HDM-AR with or without controlled asthma were treated with 300IR or placebo in 8 RCTs. Reported treatment-emergent adverse events (TEAEs) were pooled and analyzed descriptively in subsets of adults/adolescents and children. Adverse reactions (ADRs) collected from spontaneous reporting and PM studies through a pharmacovigilance system since the first marketing authorization were also analyzed.

Results

Across RCTs, 1853 subjects were treated with the 300IR HDM-SLIT tablet and 1846 with placebo. In both subsets of adults/adolescents and children whichever their asthma status, treatment-related TEAEs of higher incidence in active groups vs placebo were mostly consistent with mild or moderate local application-site reactions. They were mainly reported on the first days of treatment and decreased over time. 4 severe laryngopharyngeal reactions (2 requiring adrenaline/epinephrine) and 1 moderate eczema considered serious rapidly resolved with medications; no anaphylaxis was reported. In PM settings, ADRs reported in more than 235,000 patients were in line with RCT findings. Severe systemic reactions occurred rarely; 12 anaphylactic reactions resolved safely (5 with adrenaline). No new safety signal was raised.

Conclusion

Safety data from RCTs and more than 7 years of real-life experience confirmed the favorable safety profile of 300IR HDM-SLIT tablet in patients across different regions, regardless of age and asthma status.

Clinical trial registrations

NCT00674700; Retrospectively registered 06 May 2008.NCT01199133; Retrospectively registered 09 September 2010.NCT01527188; Retrospectively registered 01 February 2012.NCT02443805; Registered 29 April 2015/EudraCT 2014-004223-46; Registered 16 September 2015.jRCT2080221872/JapicCTI-121917; Registered 01 August 2012.jRCT2080222929/JapicCTI-15298; Registered 04 August 2015.

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.

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.

Current advances in house dust mite allergen immunotherapy (AIT): Routes of administration, biomarkers and molecular allergen profiling

Allergy to house dust mites (HDM) is a perennial respiratory disease that affect more than half a billion people worldwide. Dermatophagoides pteronyssinus and D. farinae, two HDM species, are major sources of indoor allergens triggering allergic inflammation. Although symptomatic drugs are widely used to block the allergic reaction, allergen immunotherapy is the only curative treatment of IgE-mediated type I respiratory allergies. In this article, we review recent advances in various routes of allergen immunotherapy. We particularly focus on subcutaneous (SCIT) and sublingual (SLIT) immunotherapy, used as a reference therapy since they have transformed allergic treatments by improving symptoms (asthma and rhinitis) as well as the quality of life of patients. We also highlight recent data in more exploratory routes (i.e., oral, intralymphatic, epicutaneous and intradermal) and discuss respective advantages of various route, as well as their foreseen modes of action. Finally, we provide an update on biomarkers as well as on the relevance of the molecular profiling of allergic individuals related to treatment efficacy or asthma prediction.

Single-cell immunoprofiling after immunotherapy for allergic rhinitis reveals functional suppression of pathogenic Th2 cells and clonal conversion

BACKGROUND

Allergic rhinitis is a growing problem worldwide. Currently, the only treatment that can modify the disease is antigen-specific immunotherapy; however, its mechanism(s) of action is not fully understood.

OBJECTIVE

To comprehensively investigate the role and changes of antigen-specific T cells before and after sublingual immunotherapy (SLIT) for Japanese cedar pollinosis (JCP).

METHODS

We cultured PBMCs obtained both before and at 1 year after initiating SLIT and used a combination of single-cell RNA sequence and repertoire sequencing. To investigate biomarkers, we used PBMCs from patients participating a phase II/III trial of SLIT tablets for JCP and PBMCs from good and poor responders in outpatients.

RESULTS

Antigen-stimulated culturing after SLIT led to clonal expansion of Th2 and Treg cells, and most of these CD4⁺ T cells retained their CDR3 regions before and after treatment, indicating antigen-specific clonal responses and differentiation secondary to SLIT. However, SLIT reduced the number of clonal functional Th2 cells but increased the Trans-type Th2 cell population that expresses musculin (MSC), TGF-β, and IL-2. Trajectory analysis suggested that SLIT induced clonal differentiation of the Trans-type Th2 cells differentiated into Treg cells. Using real-time PCR, we found that the MSC levels increased in the active SLIT group and good responders after 1 year of treatment.

CONCLUSION

The combination of single-cell RNA sequencing and repertoire analysis helped reveal a part of the underlying mechanism-that SLIT promotes the expression of MSC on pathogenic Th2 cells and suppresses their function; MSC may be a potential biomarker of SLIT for allergic rhinitis.

Clinical efficacy of sublingual allergen-specific immunotherapy in 22 cats with atopic dermatitis

BACKGROUND

Sublingual immunotherapy (SLIT) has been deployed in humans and dogs; to the best of the authors' knowledge, there are no published studies about the use of SLIT in cats.

OBJECTIVES

Evaluate the clinical efficacy of SLIT in atopic cats sensitized to dust and storage mites, assessing immunological changes associated with SLIT treatment.

ANIMALS

Twenty-two client-owned cats with clinical signs compatible with feline atopic dermatitis (fAD) and serum allergen-specific immunoglobulin (Ig)E against house dust and storage mites.

METHODS AND MATERIALS

Prospective, multicentre, open-label clinical trial. Individualized mite-specific SLIT was administered orally for 12 months. All cats underwent clinical examination to record SCORing feline allergic dermatitis (SCORFAD), pruritus Visual Analog Scale (pVAS) and serum allergen-specific IgE and IgG, every three months for 12 months.

RESULTS

Sixteen of 22 cats (73%) completed the study and three of six cats withdrawn from the study were included in an intention-to-treat analysis. SCORFAD and pVAS values decreased significantly from baseline (T0) to the third month of treatment (P = 0.0004 and P = 0.0013, respectively), with median total values ranging from 19 (6-44) (T0) to 2.5 (0-17) (T12) (P = 0.0001), and from 8 (6-10) (T0) to 2.3 (0-8) (T12) (P = 0.0001), respectively. Allergen-specific IgE values decreased significantly from the ninth month (T9) of treatment (P = 0.0032), with median scores decreasing from 56 (12-729) (T0) to 34 (0-158) (T12) (P = 0.0208). No significant differences in allergen-specific IgG values were observed throughout the study. No adverse effects related to the use of SLIT were reported.

CONCLUSIONS AND CLINICAL IMPORTANCE

Sublingual immunotherapy should be considered a rapid, effective, safe and well-tolerated treatment in cats with feline atopic dermatitis fAD.

Coadministration of Sublingual Immunotherapy Tablets and Management of Potential Adverse Effects: Austrian, German, and Swiss Expert Recommendations

Sublingual immunotherapy (SLIT) is currently available as liquid drops and tablets for treatment of allergic patients. Because several allergens are available and many patients are polyallergic, it is possible to treat patients with multiple clinically relevant allergies by >1 SLIT product. Austrian, German, and Swiss medical experts discussed the available data on allergen uptake at the oral mucosa and recently published data on coadministration of a grass and a ragweed tablet. The experts agreed on a schedule considering data from a North American trial on sequential administration of 2 SLIT-tablets with different allergens and their own experiences made during initiation of treatment with >1 SLIT-tablet in their clinics and subsequent self-administration by the patient and discussed the handling and management of potential adverse drug reactions (ADRs). According to the medical experts' opinion, tolerability at each phase of administration and patient preference should be taken into consideration to ensure a high level of adherence to treatment. Local ADRs that are uncomfortable for the patient may be alleviated by a 2- to 4-week course of antihistamine pretreatment. ADRs with severe swelling and/or systemic ADRs need the physician's particular attention and a decision together with the patient on continuation of treatment with SLIT or possible alternative routes of administration.