Peripheral blood mononuclear cell transcriptome profile in a clinical trial with subcutaneous, grass pollen allergoid immunotherapy.

INTRODUCTION: Allergen-specific immunotherapy (AIT) is the only disease-modifying treatment in allergic airway diseases. Underlying immunological mechanisms and candidate biomarkers, which may be translated into predictive/surrogate measures of clinical efficacy, remain an active area of research. The aim of this study was to evaluate Pollinex Quattro (PQ) Grass AIT induced immunomodulatory mechanisms, based on transcriptome profiling of peripheral blood mononuclear cells. METHODS: 119 subjects with grass pollen induced seasonal allergic rhinitis (SAR) were randomized in a 2:2:1:1 ratio to receive a cumulative dose of PQ Grass as a conventional or extended pre-seasonal regimen, placebo, or placebo with MicroCrystalline Tyrosine. Gene expression analysis was an exploratory endpoint evaluated in a subgroup of 30 subjects randomly selected from the four treatment arms. Samples were collected at three time points: screening (baseline), before the start of the grass pollen season and at the end of the season. This study was funded by the manufacturer of PQ. RESULTS: Transcriptome analysis demonstrated that the most significant changes in gene expression, for both treatment regimens, were at the end of the grass pollen season, with the main Th1 candidate molecules (IL-12A, IFNγ) upregulated and Th2 signature cytokines downregulated (IL-4, IL-13, IL-9) (p < .05). Canonical pathways analysis demonstrated Th1, Th2, Th17 and IL-17 as the most significantly enriched pathways based on absolute value of activation z-score (IzI score ≥ 2, p < .05). Upstream regulator analysis showed pronounced inhibition of pro-inflammatory allergic molecules IgE, IL-17A, IL-17F, IL-25 (IL-17E) (IzI score ≥ 2, FDR < 0.05) and activation of pro-tolerogenic molecules IL-12A, IL-27, IL-35 (EBI3) at the end of the grass pollen season. CONCLUSION: Peripheral blood mononuclear cells transcriptome profile showed an inhibition of Th2, Th17 pro-inflammatory allergic responses and immune deviation towards Th1 responses. PQ Grass extended regimen exhibited a superior mechanistic efficacy profile in comparison with PQ conventional regimen.

Long-term effects of pollen allergoid tyrosine-adsorbed subcutaneous immunotherapy on allergic rhinitis and asthma.

BACKGROUND: Allergen immunotherapy (AIT) may have a long-term disease-modifying effect. The aim of this study was to demonstrate the long-term effects of pollen allergoid tyrosine-adsorbed subcutaneous AIT on allergic rhinitis (AR) and asthma (AA) in clinical practice. METHODS: This retrospective study, funded by an AIT manufacturer, analysed the impact of AIT on AR progression and onset of need for AA medication, using a German database covering ~35% of national prescriptions during 2008-2020. Anonymized prescription data of AR patients aged 5-65 years treated with grass or tree pollen AIT between 2009 and 2013 and followed for at least 2 years after AIT cessation were compared with matched control patients with seasonal AR. RESULTS: 181,496 patients received AIT prescriptions. 5959 fulfilled the inclusion criteria. The median AIT treatment duration was 1092 days and the follow-up duration was 6.4 years. Less patients treated with AIT received prescriptions for symptomatic AR medication in the follow-up versus controls (AIT: OR: 0.37; 95% Confidence Interval (CI) 0.34, 0.40; p < .001, tyrosine-adsorbed AIT: OR: 0.27; 95% CI 0.20, 0.35 p < .001). Less asthmatic patients under AIT received prescriptions for AA medications versus controls (AIT: OR: 0.48; 95% CI 0.41, 0.55; p < .001, tyrosine-adsorbed AIT: OR: 0.48; 95% CI 0.29, 0.79; p = .004). AR and AA medication prescriptions for AIT patients were reduced in the follow-up versus baseline and controls (AIT: AR: 20.0%; 1.5 vs. 0.2 prescriptions; AA: 29.1%; 2.0 vs. 0.6 prescriptions, p < .001; tyrosine-adsorbed AIT: AR: 24.2%, 1.4 vs. 0.2 prescriptions; AA: 35.6%, 2.1 vs. 0.6 prescriptions, p < .001). The probability of AA medication onset in non-asthmatic patients during follow-up was reduced for AIT patients compared to controls (OR: 0.77, 95% CI 0.66, 0.90; p = .001). All endpoints were significant for children/adolescents and adults in stratified analyses. CONCLUSIONS: We found evidence for long-term effects up to 9.5 years for tyrosine-adsorbed AIT.

Single-cell RNA sequencing identifies precise tolerogenic cellular and molecular pathways induced by depigmented-polymerized grass pollen allergen extract.

BACKGROUND: Immunologic mechanism of action of allergoids remains poorly understood. Previous models of allergenicity and immunogenicity have yielded suboptimal knowledge of these immunotherapeutic vaccine products. Novel single-cell RNA sequencing technology offers a bridge to this gap in knowledge. OBJECTIVE: We sought to identify the underpinning tolerogenic molecular and cellular mechanisms of depigmented-polymerized Phleum pratense (Phl p) extract. METHODS: The molecular mechanisms underlying native Phl p, depigmented Phl p (DPG-Phl p), and depigmented-polymerized (DPG-POL-Phl p) allergoid were investigated by single-cell RNA sequencing. Allergen-specific TH2A, T follicular helper (Tfh), and IL-10+ regulatory B cells were quantified by flow cytometry in peripheral blood mononuclear cells from 16 grass pollen-allergic and 8 nonatopic control subjects. The ability of Phl p, DPG-Phl p, and DPG-POL-Phl p to elicit FcεRI- and FcεRII-mediated IgE responses was measured by basophil activation test and IgE-facilitated allergen binding assay. RESULTS: Analysis revealed that DPG-POL-Phl p downregulated genes associated with TH2 signaling, induced functional regulatory T cells exhibiting immunosuppressive roles through CD52 and Siglec-10, modulated genes encoding immunoproteasome that dysregulate the processing and presentation of antigens to T cells and promoted a shift from IgE toward an IgA1 and IgG responses. In grass pollen-allergic subjects, DPG-POL-Phl p exhibited reduced capacity to elicit proliferation of TH2A, IL-4+ Tfh and IL-21+ Tfh cells while being the most prominent at inducing IL-10+CD19+CD5hi and IL-10+CD19+CD5hiCD38intCD24int regulatory B-cell subsets compared to Phl p (all P < .05). Furthermore, DPG-POL-Phl p demonstrated a hypoallergenic profile through basophil activation and histamine release compared to Phl p (31.54-fold, P < .001). CONCLUSIONS: Single-cell RNA sequencing provides an in-depth resolution of the mechanisms underlying the tolerogenic profile of DPG-POL-Phl p.

Comparison of perennial and preseasonal allergoid immunotherapy in grass pollen allergic patients.

BACKGROUND: The clinical and immunological efficacy of preseasonal allergoid immunotherapy has been previously investigated, however, studies comparing the effectiveness of the two protocols are limited in the literature. OBJECTIVE: The aim of this study is to compare the clinical and immunological efficacy of pre-seasonal and perennial allergoid immunotherapy. METHODS: This is a prospective cross sectional two-arm study. During the season; symptom and medication scores were filled. Before and at the end of the season; RQLQ was applied, Phl p sIgE, sIgG4 and IL-10 levels were measured. RESULTS: In preseasonal group patients had better symptom control for most of the weeks, particularly during the peak pollen period (April: w-2 & w-4, p = 0.04; May: w-2, p = 0.02; June: w-1, w-2, p = 0.02; w-3, w-5, p = 0.03; July: w-2, p = 0.01; w-3, p = 0.02; w-4, p = 0.04). In the perennial group, sIgG4 [1st time point: preseasonal 0.02 mgA/L vs perennial 0.13 mgA/L (p < 0.0001); 2nd time point: preseasonal 0.52 mgA/L vs perennial 0.33 mgA/L; 3rd time point: preseasonal 0.04 mgA/L vs perennial 0.12 mgA/L (p < 0.0001)] and IL-10 (1st time point: preseasonal 1.45 pg/ml vs perennial 2.03 pg/ml; 2nd time point: preseasonal 2.29 pg/ml vs perennial 2.19 pg/ml; 3rd time point: preseasonal 2.32 pg/ml vs perennial 2.16 pg/ml) levels were higher and more stable. CONCLUSIONS: Preseasonal immunotherapy provided better control of symptoms throughout the pollen season. However, the blocking antibody response was stronger and more permanent in the perennial immunotherapy group.

Effect of moderate to severe atopic dermatitis on the prognosis of egg allergy resolution

BACKGROUND: Few studies have examined the effect of atopic dermatitis (AD) on the resolution of food allergies in Asia, and the predictors of egg allergy resolution are not yet well defined. OBJECTIVE: We evaluated whether AD severity could predict the resolution of egg allergy. METHODS: This retrospective cohort study included infants under 24 months of age diagnosed with IgE-mediated egg white allergy. We included subjects who completed a 60-month follow-up. Open oral food challenges (OFCs) and serologic tests were performed at the time of initial diagnosis and at 36 ± 3 and 60 ± 3 months. RESULTS: We analyzed 68 patients (39 boys and 29 girls). OFCs were performed in 88.2% of the patients. The egg allergy remission rates were 23.5% and 47.1% by 3 and by 5 years of age, respectively. Persistent egg allergy was significantly associated with moderate to severe AD and house dust mite sensitization. Kaplan-Meier curve analysis revealed that patients with moderate to severe AD had higher persistent egg allergy rates than patients with no and mild AD (p = 0.012). Multivariable analysis identified moderate to severe AD as strongly associated with persistent egg allergy (p = 0.001). CONCLUSIONS: In this study, 47.1% of infants had resolved egg white allergies at 60 months. Moderate to severe AD may be a practical and important prognostic factor for persistent egg allergy in clinical settings.

Comparison of Intact Allergen Extracts and Allergoids For Subcutaneous Immunotherapy: The Effect of Chemical Modification Differs Both Between Species and Between Individual Allergen Molecules.

BACKGROUND: Allergen products for subcutaneous immunotherapy (SCIT) contain intact allergen extracts or chemically modified allergoids. Chemical modification was introduced to reduce allergenicity while retaining immunogenicity and thereby enable safer and more efficient allergy immunotherapy. METHODS: Experimental allergoids were produced from intact allergen extract for birch, grass, and house dust mite (HDM) to evaluate the effects of chemical modification. Preparations were compared with commercial allergoids and analyzed using SDS-PAGE/immunoblotting, IgE-inhibition assays, and crossed immunoelectrophoresis (CIE). Dermatophagoides pteronyssinus (Der p) vaccines were also tested for protease activity and immunizing capacity in a mouse model. RESULTS: The composition of IgE-binding epitopes in allergoids differed from that of intact allergen vaccines. Birch and grass allergoids produced smears of protein aggregates on SDS-PAGE, whereas intact allergen preparations showed distinct protein bands as expected. Der p allergoid vaccines, however, showed a distinct protein band corresponding to major allergen Der p 1 in both SDS-PAGE and CIE analysis, and commercial Der p allergoid vaccines showed Der p 1-related cysteine protease activity. CONCLUSION: Allergoids and intact allergen preparations differ with respect to the composition of IgE-binding epitopes. However, chemical cross-linking does not affect every allergen molecule to the same degree. Der p 1, for example, remains largely unmodified. Furthermore, the investigational HDM allergoid vaccines showed reduced and delayed immune responses when used for immunization of mice.

Safety of subcutaneous immunotherapy with carbamylated allergoids based on data from a pharmacovigilance database.

Aims: Allergen immunotherapy aims to induce tolerance, which persists after its discontinuation, to targeted allergens. However, concern exists regarding the use of subcutaneous immunotherapy with whole extracts due to frequently reported events of anaphylactic reactions. Materials & methods: In this pharmacovigilance study, the authors assessed the safety of subcutaneous immunotherapy with the monomeric allergoid Lais-in using a database of adverse reactions documented in real-world postmarketing reports from 2010 to 2020. Results & conclusion: The results showed that more than 171,916 doses of Lais-in were administered from 2010 to 2020, resulting in five adverse drug reactions. Nonserious adverse events, including hives, eye irritation and skin reactions, were reported. These data indicate that monomeric allergoids prevent serious reactions to subcutaneous immunotherapy.

Effectiveness and safety of a microcrystalline tyrosine-adjuvanted Dermatophagoides pteronyssinus allergoid immunotherapy in adult patients with allergic asthma and rhinitis: A real-life prospective observational study.

INTRODUCTION: Although clinical trials have shown the efficacy and safety of allergen-specific immunotherapy (AIT) in the treatment of allergic asthma, there is a need for real-life studies. We aimed to assess the effectiveness and safety of a microcrystalline tyrosine-adjuvanted Dermatophagoides pteronyssinus allergoid (Acarovac Plus®) in patients with house dust mite (HDM)-induced allergic asthma in a real-life study. METHODS: A subanalysis of a multicenter, prospective, observational, real-life study. Patients with rhinitis and allergic asthma caused by HDMs were assessed before AIT with Acarovac Plus® and at 6 and 12 months after this treatment. Assessment parameters were percentage of days with asthma symptoms, percentage of days on asthma medication, classification of asthma according to Spanish guidelines for the management of asthma, asthma-related quality of life (quality of life in adults with asthma questionnaire [QLAAQ]), perception of symptoms (visual analog scale [VAS]), and treatment satisfaction (treatment satisfaction questionnaire for medication [TSQM]). Safety was assessed by the number and severity of adverse reactions. RESULTS: This subanalysis included 55 patients. Treatment with Acarovac Plus® showed significant differences in the analyzed variables when the baseline visit was compared with the 12-month visit: reduction of the mean (SD) percentage of days with asthma symptoms (23.9 [9.2] vs. 5.1 [12.8]; p = .002), of the mean [SD] percentage of days on asthma medication (67.6 [42.9] vs. 45.1 [46.8]; p = .002), and of the percentage of patients with persistent asthma (78.2% vs. 38.9%; p = .009). Acarovac Plus® significantly improved asthma-related quality of life, as shown by a decrease of 1.39 points in QLAAQ score at 12 months (p < .001), and in the subjective perception of symptoms on the VAS (-3.50, p < .0001). Patients showed high treatment satisfaction according to the TSQM, and it was well tolerated. No serious adverse events were reported. CONCLUSIONS: Acarovac Plus® was effective and safe for the treatment of patients with HDM-induced allergic asthma in a real-life study.

Immunological mechanisms involved in the human response to a dog dander allergoid.

BACKGROUND: Dog allergens are a common cause of allergic sensitisation and trigger respiratory symptoms worldwide. However, clinical evidence regarding dog immunotherapy is limited. Therefore, the aim of this study was to analyse the immunomodulatory properties of a new allergoid from dog dander, thereby deepening the understanding of the molecular mechanisms involved in the reestablishment of the tolerogenic response. METHODS: Three independent batches of dog dander native and allergoid allergen extracts were manufactured and characterised. Allergenic profiles were analysed by the identification of all dog allergens and quantification of the major allergens Can f 1 and Can f 5. The allergenicity profile of the allergoid was studied using biological potency and basophil activation tests. In vitro immunomodulatory parameters was evaluated as the capacity of the allergoid to induce IgG antibodies that block IgE binding to the allergen and cytokine promotion (IFN-γ, IL-4, IL-6, IL-10, IL-13, and TNF-α) in PBMCs from allergic donors. RESULTS: The presence of all dog allergens, including Can f 1 and Can f 5, was confirmed in both types of extracts. The new allergoid showed a low IgE binding capacity, which significantly affected the activation of effector cells, such as basophils. The IgG antibodies induced by the allergoid in rabbits blocked human IgE binding epitopes on the dog native extract and induced Th1 and Treg responses by increasing IFN-γ and IL-10 levels in PBMCs from allergic donors. CONCLUSION: This new dog dander allergoid containing Can f 1 and Can f 5 showed a low capacity to bind IgE and to activate basophils in dog allergic patients. Furthermore, it showed potent activation of Th1 mediators and induction of tolerance through Treg activation. This allergoid could offer a safer profile than the native extract and could be an effective immunotherapy treatment for dog allergic patients.

Immunological effects of adjuvanted low-dose allergoid allergen-specific immunotherapy in experimental murine house dust mite allergy.

BACKGROUND: Native allergen extracts or chemically modified allergoids are routinely used to induce allergen tolerance in allergen-specific immunotherapy (AIT), although mechanistic side-by-side studies are rare. It is paramount to balance optimal dose and allergenicity to achieve efficacy warranting safety. AIT safety and efficacy could be addressed by allergen dose reduction and/or use of allergoids and immunostimulatory adjuvants, respectively. In this study, immunological effects of experimental house dust mite (HDM) AIT were investigated applying high-dose HDM extract and low-dose HDM allergoids with and without the adjuvants microcrystalline tyrosine (MCT) and monophosphoryl lipid A (MPL) in a murine model of HDM allergy. METHODS: Cellular, humoral, and clinical effects of the different AIT strategies were assessed applying a new experimental AIT model of murine allergic asthma based on physiological, adjuvant-free intranasal sensitization followed by subcutaneous AIT. RESULTS: While low-dose allergoid and high-dose extract AIT demonstrated comparable potency to suppress allergic airway inflammation and Th2-type cytokine secretion of lung-resident lymphocytes and draining lymph node cells, low-dose allergoid AIT was less effective in inducing a potentially protective IgG1 response. Combining low-dose allergoid AIT with MCT or MCT and dose-adjusted MPL promoted Th1-inducing mechanisms and robust B-cell activation counterbalancing the allergic Th2 immune response. CONCLUSION: Low allergen doses induce cellular and humoral mechanisms counteracting Th2-driven inflammation by using allergoids and dose-adjusted adjuvants. In light of safety and efficacy improvement, future therapeutic approaches may use low-dose allergoid strategies to drive cellular tolerance and adjuvants to modulate humoral responses.

Allergoid-mannan conjugates reprogram monocytes into tolerogenic dendritic cells via epigenetic and metabolic rewiring.

BACKGROUND: Allergoid-mannan conjugates are novel vaccines for allergen-specific immunotherapy being currently assayed in phase 2 clinical trials. Allergoid-mannan conjugates target dendritic cells (DCs) and generate functional forkhead box P3 (FOXP3)-positive Treg cells, but their capacity to reprogram monocyte differentiation remains unknown. OBJECTIVE: We studied whether allergoid-mannan conjugates could reprogram monocyte differentiation into tolerogenic DCs and the underlying molecular mechanisms. METHODS: Monocytes from nonatopic and allergic subjects were differentiated into DCs under conventional protocols in the absence or presence of allergoid-mannan conjugates. ELISA, real-time quantitative PCR, coculture, flow cytometry, and suppression assay were performed. Metabolic and epigenetic techniques were also used. RESULTS: Monocyte differentiation from nonatopic and allergic subjects into DCs in the presence of allergoid-mannan conjugates yields stable tolerogenic DCs. Lipopolysaccharide-stimulated mannan-tolDCs show a significantly lower cytokine production, lower TNF-α/IL-10 ratio, and higher expression of the tolerogenic molecules PDL1, IDO, SOCS1, SOCS3, and IL10; and they induce higher numbers of functional FOXP3+ Treg cells than conventional DC counterparts. Mannan-tolDCs shift glucose metabolism from Warburg effect and lactate production to mitochondrial oxidative phosphorylation. They also display epigenetic reprogramming involving specific histone marks within tolerogenic loci and lower expression levels of histone deacetylase genes. Mannan-tolDCs significantly increase the expression of the anti-inflammatory miRNA-146a/b and decrease proinflammatory miRNA-155. CONCLUSIONS: Allergoid-mannan conjugates reprogram monocyte differentiation into stable tolerogenic DCs via epigenetic and metabolic reprogramming. Our findings shed light on the novel mechanisms by which allergoid-mannan conjugates might contribute to allergen tolerance induction during allergen-specific immunotherapy.

Evaluation of safety and tolerability of a rush up-dosing allergen-specific immunotherapy with grass pollen, birch, hazel, and alder allergoid in children with allergic rhinoconjunctivitis, with or without asthma.

BACKGROUND Usually, the number of injections required to achieve the maintenance dose in subcutaneous immunotherapy (SCIT) is relatively small for some of the currently used allergens, but this may still be uncomfortable for patients, thus compromising adherence and compliance. OBJECTIVE The purpose of this study was to evaluate the safety and tolerability of a dose acceleration of a conventional induction schedule using an allergoid extract of grass pollen, birch, hazel, and alder, needed to achieve the ideal maintenance dose. METHODS In this open-label study, 34 patients with allergic rhinoconjunctivitis, with or without asthma, were treated with SCIT using an allergoid for grass pollen or birch or mix trees with an increase in accelerated induction dose comprising only 3 injections, one per week, compared to a conventional induction pattern in five injections (once a week). Safety determination was assessed by evaluating local and systemic adverse events. Tolerability was evaluated by patients and physicians who performed the treatment. RESULTS No treatment-related adverse events were observed in any of the patients undergoing rush SCIT. No local reactions, no systemic reactions of any degree (WAO Grade) have been observed. Tolerability has always been rated as very good by both patients and physician. CONCLUSIONS The induction phase, needed to achieve the monthly maintenance dose for a pollen extract, can be greatly accelerated, ensuring a tolerability comparable to that of the conventional schedule.

Accelerated Dose Escalation with 3 Injections of an Aluminum Hydroxide-Adsorbed Allergoid Preparation of 6 Grasses Is Safe for Children and Adolescents with Moderate to Severe Allergic Rhinitis.

A high-dose, accelerated escalation schedule during subcutaneous allergen-specific immunotherapy (AIT) is safe and well-tolerated in adults. However, there are no data in children and adolescents. The aim of the present trial was to assess safety and tolerability of an accelerated dose escalation schedule of an AIT with a grass pollen allergoid in children and adolescents with moderate to severe seasonal rhinoconjunctivitis in a multicenter, open-label, randomized phase II trial. The dose escalation scheme for patients in the One Strength Group included 3 injections with 1 strength B (10,000 TU/mL), whereas the dose escalation scheme for the Standard group included 7 injections with 2 strengths A (1,000 TU/mL) and B (10,000 TU/mL) of an allergoid grass pollen preparation. Overall, n = 50 children (n = 25 in each group; mean age 8.9 + 1.54 years) and n = 37 adolescents (n = 20 and n = 17; 14.2 + 1.62 years) were randomized. For all patients, the mean treatment duration was 59.4 days in the One Strength group and 88.6 days in the Standard group. Treatment-emergent adverse events (TEAEs) related to AIT were reported in 52 and 40% in children and 35 and 35.3% in adolescents, respectively. Systemic allergic reactions occurred in about 5% of our patients and were reported in more patients of the One Strength group (6.7 vs. 2.4%). All systemic reactions were classified as WAO Grade 1. Accelerated high-dose escalation with an aluminum hydroxide-adsorbed grass pollen allergoid can be initiated with a safety and tolerability profile comparable to the standard dose escalation schedule in children and adolescents with allergic rhinitis with or without asthma.

A non-stationary Markov model for economic evaluation of grass pollen allergoid immunotherapy.

INTRODUCTION: Allergic rhino-conjunctivitis (ARC) is an IgE-mediated disease that occurs after exposure to indoor or outdoor allergens, or to non-specific triggers. Effective treatment options for seasonal ARC are available, but the economic aspects and burden of these therapies are not of secondary importance, also considered that the prevalence of ARC has been estimated at 23% in Europe. For these reasons, we propose a novel flexible cost-effectiveness analysis (CEA) model, intended to provide healthcare professionals and policymakers with useful information aimed at cost-effective interventions for grass-pollen induced allergic rhino-conjunctivitis (ARC). METHODS: Treatments compared are: 1. no AIT, first-line symptomatic drug-therapy with no allergoid immunotherapy (AIT). 2. SCIT, subcutaneous immunotherapy. 3. SLIT, sublingual immunotherapy. The proposed model is a non-stationary Markovian model, that is flexible enough to reflect those treatment-related problems often encountered in real-life and clinical practice, but that cannot be adequately represented in randomized clinical trials (RCTs). At the same time, we described in detail all the structural elements of the model as well as its input parameters, in order to minimize any issue of transparency and facilitate the reproducibility and circulation of the results among researchers. RESULTS: Using the no AIT strategy as a comparator, and the Incremental Cost Effectiveness Ratio (ICER) as a statistic to summarize the cost-effectiveness of a health care intervention, we could conclude that: SCIT systematically outperforms SLIT, except when a full societal perspective is considered. For example, for T = 9 and a pollen season of 60 days, we have ICER = €16,729 for SCIT vs. ICER = €15,116 for SLIT (in the full societal perspective).For longer pollen seasons or longer follow-up duration the ICER decreases, because each patient experiences a greater clinical benefit over a larger time span, and Quality-adjusted Life Year (QALYs) gained per cycle increase accordingly.Assuming that no clinical benefit is achieved after premature discontinuation, and that at least three years of immunotherapy are required to improve clinical manifestations and perceiving a better quality of life, ICERs become far greater than €30,000.If the immunotherapy is effective only at the peak of the pollen season, the relative ICERs rise sharply. For example, in the scenario where no clinical benefit is present after premature discontinuation of immunotherapy, we have ICER = €74,770 for SCIT vs. ICER = €152,110 for SLIT.The distance between SCIT and SLIT strongly depends on under which model the interventions are meta-analyzed. CONCLUSIONS: Even though there is a considerable evidence that SCIT outperforms SLIT, we could not state that both SCIT and SLIT (or only one of these two) can be considered cost-effective for ARC, as a reliable threshold value for cost-effectiveness set by national regulatory agencies for pharmaceutical products is missing. Moreover, the impact of model input parameters uncertainty on the reliability of our conclusions needs to be investigated further.

The role of allergoids in allergen immunotherapy: from injective to sublingual route.

Summary: Summary Allergen immunotherapy (AIT) is aimed at inducing tolerance to allergens, such as pollens, dust mites or moulds, by administering increasing amounts of the causative allergen through subcutaneous or sublingual route. The evidence of efficacy of AIT is high, but the issue of safety, especially for the subcutaneous route, must be taken into account. The search for safer AIT products aimed at reducing the allergenicity, and thus adverse reactions, while maintaining the immunogenicity, that is essential for effectiveness, gave rise to the introduction of allergoids, which were conceived to fulfill these requirements. In the first allergoids glutaraldehyde or formaldehyde were used as cross-linking agent to polymerize allergens, this resulting in high molecular weight molecules (200,000 to 20,000,000 daltons) which were significantly less allergenic due to a decreased capacity to bridge IgE on its specific receptor, while maintaining the immunogenicity and thus the therapeutic efficacy. In recent years further agents, acting as adjuvants, such as L-tyrosine, monophosphoryl lipid A, aluminium hydroxide, were added to polymerized extracts. Moreover, a carbamylated monomeric allergoid was developed and, once adsorbed on calcium phosphate matrix, used by subcutaneous route. At the same time, in virtue of its peculiarities, such allergoid revealed particularly suitable for sublingual administration. A lot of clinical evidences show that it is well tolerated, largely safer and effective. Importantly, the higher safety of allergoids allows faster treatment schedules that favor patient compliance and, according to pharmaco-economic studies, they might be more cost-effective than other AIT options.

Accelerated Dose Escalation with Three Injections of an Aluminum Hydroxide-Adsorbed Allergoid Preparation of Six Grasses Is Safe for Patients with Moderate to Severe Allergic Rhinitis.

Only few data on safety during high-dose, accelerated escalation schedules during subcutaneous allergen immunotherapy (AIT) are available. The aim of this study was to assess the safety and tolerability of an accelerated dose escalation schedule of AIT in adult patients with moderate to severe seasonal rhinoconjunctivitis in a multicenter, open-label, randomized phase II trial. The dose escalation scheme for patients in Group I (1 strength) included 3 injections with 1 strength, B (10,000 TU/mL), whereas the dose escalation scheme for Group II (standard) included 7 injections with 2 strengths, A (1,000 TU/mL) and B (10,000 TU/mL), of an aluminum hydroxide-adsorbed allergoid grass pollen preparation. Overall, 72 of 87 randomized patients (83.7%) reported at least 1 treatment-emergent adverse event (TEAE; 82.2 [Group I] vs. 85.4% [Group II]); 58.8% of all reported TEAEs were assessed as being related to AIT (60.0 vs. 48.8%). The most frequently reported AIT-related TEAEs were swelling (46.7 vs. 34.1%), erythema (28.9 vs. 36.6%), and pruritus (31.1 vs. 17.1%) at the site of the injection. Systemic allergic reactions occurred in 5 (5.8%) patients overall, with more being reported in the 1-strength group (4 [8.9%] vs. 1 [2.4%]). All systemic allergic reactions were classified as World Allergy Organization (WAO) Grade 1 or Grade 2 reactions. Accelerated high-dose escalation with an aluminum hydroxide-adsorbed grass pollen allergoid can be initiated with a safety and tolerability profile comparable to the standard dose escalation schedule in patients with allergic rhinitis with or without asthma.

Year-round treatment initiation for a 6-grasses pollen allergoid in specific immunotherapy of allergic rhinoconjunctivitis and asthma.

Aim: Allergen immunotherapy (AIT) is an effective treatment for allergic diseases. We investigate whether treatment-initiation during the pollen season is safe. Methods: RCT-IIIb-trial of 6-grass-pollen-allergoid (Allergovit®) in grass pollen-allergic patients (18-65 years) with moderate-severe rhinitis/rhinoconjunctivitis (± controlled asthma), randomized 2:1 to treatment-initiation during (Group-A) versus outside the pollen season (Group-B). Results: Of 240 patients (32.8 ± 9.9 years, 19.5% asthma) treated, 84.9% (Group-A) and 86.6% (Group-B) reached maintenance dose without delay. Treatment-emergent adverse events occurred in 108 (68.4%/Group-A) and 41 patients (56.2%/Group-B) leading to premature trial-termination in 11 patients (7%/A) versus 3 (4.1%/B). Across groups, physicians (for 190 patients; 85.2%) and patients (192; 86.1%) rated the tolerability as 'very good'-'good'. Phleum pratense-specific IgG4 increased in both groups (p < 0.0001). Conclusion: Year-round allergen immunotherapy-initiation with this preparation is safe.