Ultra-short-course seasonal allergy vaccine (Pollinex Quattro)

Effectiveness and safety of a glutaraldehyde-modified, L-tyrosine-adsorbed and monophosphoryl lipid A-Adjuvanted allergen immunotherapy in patients with allergic asthma sensitized to olive pollen: A retrospective, controlled real-world study

Background

Allergy to olive pollen is one of the primary causes of allergic asthma in Spain. Even though allergen immunotherapy (AIT) has shown clinical benefits in patients sensitized to different allergens, studies in asthmatic patients sensitized to olive pollen are insufficient.

Objective

To assess the effectiveness and safety of an ultra-short course of AIT with an L-tyrosine-adsorbed and monophosphoryl lipid A-adjuvanted olive pollen and olive/grass pollen extract (Pollinex Quattro®) in patients with allergic asthma in the real-world setting.

Methods

Retrospective, controlled study including patients with asthma, with and without allergic rhinitis, caused by sensitization to olive pollen from 11 centers in Spain. Patients received out-of-season (October–March) treatment with AIT in addition to their pharmacological treatment (active group) or pharmacological treatment (control group). Effectiveness variables, including unscheduled visits to the healthcare center, emergency room admissions, symptoms of asthma and rhinitis (following GEMA and ARIA classifications, respectively), and use of medication to treat asthma and rhinitis during the subsequent pollen season were compared between treatment groups.

Results

Of 131 study patients, 42 were treated with their usual asthma medication (control group) and 89 were treated with AIT (active group), either Pollinex Quattro® 100% olive pollen (n = 43, 48.3%) or 50% olive pollen/50% grass pollen (n = 46, 51.7%). Patients’ demographic and clinical characteristics were similar between groups. The mean (SD) number of unscheduled visits to a healthcare center and emergency room admissions due to allergy symptoms was 2.19 (1.40) and 0.43 (0.63) in the control group, and 1.09 (1.25) and 0.11 (0.51) in the active group (P = 0.001 and P = 0.006, respectively). Severity and control of asthma symptoms remained unchanged (P = 0.347 and P = 0.179, respectively), rhinitis type improved (P = 0.025), and severity remained unchanged in the active compared to the control group. The use of short-acting beta-agonists and inhaled corticosteroids to treat asthma symptoms decreased in the active vs. the control group (P = 0.001 and P = 0.031, respectively). Twelve (13.5%) and two (2.2%) patients in the active group experienced local adverse reactions (edema, swelling, erythema, hives, pruritus, and heat), and systemic adverse reactions (hypertensive crisis and low-grade fever) to AIT, respectively; none was serious.

Conclusion

AIT with Pollinex Quattro® specific for olive pollen and olive/grass pollens resulted in reduced visits to the healthcare center and emergency room and the use of asthma medication during the pollen season, indicating that this treatment was safe and effective in treating asthma in patients sensitized to these pollens.

Ultra-short-course booster is effective in recurrent grass pollen-induced allergic rhinoconjunctivitis

BACKGROUND

A relevant proportion of allergic rhinoconjunctivitis (ARC) patients experience recurrent symptoms after successfully completing allergen immunotherapy (AIT). This prospective, controlled, noninterventional study used internationally standardized instruments to determine the clinical effects of a preseasonal, ultra-short-course booster AIT on clinical outcome parameters.

METHODS

This two-arm study included patients aged ≥12 years with recurrent grass pollen-induced seasonal AR who had completed a successful course of any grass pollen AIT at least 5 years before enrolment. Overall, 56 patients received one preseasonal short-course booster AIT using tyrosine-absorbed grass pollen allergoids containing the adjuvant monophosphoryl lipid A (MPL® ); 51 control patients received symptomatic medication. The combined symptom and medication score (CSMS) was recorded in the (peak) grass pollen season. Furthermore, concomitant (antiallergic) medication use, the patients' state of health, Mini Rhinoconjunctivitis Quality of Life Questionnaire (MiniRQLQ) results and safety/tolerability of the treatment were assessed.

RESULTS

The CSMS in the peak grass pollen season was significantly lower in the booster AIT group (Δ=38.4%, P<.01). Moreover, significantly more patients in this group used no concomitant antiallergic medication throughout the peak grass pollen season. Twice as many patients in the booster AIT group as in the control group reported having a better state of health than in the preceding season. MiniRQLQ results showed significant differences favouring the booster AIT. The booster AIT was generally well tolerated, with only two patients reporting mild, grade 1 systemic adverse events.

CONCLUSION

Booster AIT using tyrosine-absorbed allergoids containing the adjuvant MPL® effectively prevents re-occurrence of symptoms in patients with grass pollen-induced ARC.

Adjuvants

Developing new vaccines against emerging pathogens or pathogens where variability of antigenic sites presents a challenge, the inclusion of stimulators of the innate immune system is critical to mature the immune response in a way that allows high avidity recognition while preserving the ability to react to drifted serovars. The innate immune system is an ancient mechanism for recognition of nonself and the first line of defense against pathogen insult. By triggering innate receptors, adjuvants can boost responses to vaccines and enhance the quality and magnitude of the resulting immune response. This chapter: (1) describes the innate immune system, (2) provides examples of how adjuvants are formulated to optimize their effectiveness, and (3) presents examples of how adjuvants can improve outcomes of immunization.

Fusion proteins of flagellin and the major birch pollen allergen Bet v 1 show enhanced immunogenicity, reduced allergenicity, and intrinsic adjuvanticity

BACKGROUND

Recombinant fusion proteins of flagellin and antigens have been demonstrated to induce strong innate and adaptive immune responses. Such fusion proteins can enhance the efficacy of allergen-specific immunotherapy.

OBJECTIVE

We sought to characterize different fusion proteins of flagellin and the major birch pollen allergen Bet v 1 for suitability as allergy vaccines.

METHODS

A truncated version of flagellin (NtCFlg) was genetically fused to the N- or C-terminus of Bet v 1. Toll-like receptor (TLR) 5 binding was assessed with HEK293 cells expressing TLR5. Upregulation of CD40, CD80, CD83, and CD86 on monocyte-derived dendritic cells from allergic patients was analyzed by using flow cytometry. The T cell-stimulatory capacity of the fusion proteins was assessed with naive and Bet v 1-specific T cells. IgE binding was tested in inhibition ELISAs and basophil activation tests. Mice were immunized with the fusion proteins in the absence and presence of aluminum hydroxide. Cellular and antibody responses were monitored. Murine antibodies were tested for blocking capacity in basophil activation tests.

RESULTS

Both fusion proteins matured monocyte-derived dendritic cells through TLR5. Compared with Bet v 1, the fusion proteins showed stronger T cell-stimulatory and reduced IgE-binding capacity and induced murine Bet v 1-specific antibodies in the absence of aluminum hydroxide. However, only antibodies induced by means of immunization with NtCFlg fused to the C-terminus of Bet v 1 inhibited binding of patients' IgE antibodies to Bet v 1.

CONCLUSION

Bet v 1-flagellin fusion proteins show enhanced immunogenicity, reduced allergenicity, and intrinsic adjuvanticity and thus represent promising vaccines for birch pollen allergen-specific immunotherapy. However, the sequential order of allergen and adjuvant within a fusion protein determines its immunologic characteristics.

Allergen-specific immunotherapy in asthmatic children: from the basis to clinical applications

Atopic asthma in childhood with the tendency to persist into adult life is an important issue in pediatrics. Allergen-specific immunotherapy (SIT) is the only curative treatment option for these children, being directed to the causes of the disease. The Th2 phenotype is a predominant immunological pattern in atopic asthma and SIT leads to apoptosis/anergy of T cells and induces immune-regulatory responses and immune deviation towards Th1. Many factors can affect the safety and efficacy of SIT, such as pattern of sensitization, allergy vaccine (allergen extracts, adjuvants and conjugated molecules), route of administration (subcutaneous or sublingual) and different treatment schedules. Overall, asthma symptoms and medication scores usually decrease following a SIT course and the most common observed side effects are restricted to local swelling, erythema and pruritus. Compared with conventional pharmacotherapy, SIT may be more cost effective, providing a benefit after discontinuation and a steroid-sparing effect. In addition, it can prevent new sensitizations in monosensitized asthmatic children. Microbial supplements such as probiotics, immunomodulatory substances like anti-IgE/leukotrienes, antibodies and newer allergen preparations such as recombinant forms have been tested to improve the efficacy and safety of SIT with inconclusive results. In conclusion, SIT provides an appropriate solution for childhood asthma that should be employed more often in clinical practice. Further studies are awaited to improve current knowledge regarding the mechanisms behind SIT and determine the most appropriate materials and schedule of immunotherapy for children with asthma.

Endotoxin and cancer chemo-prevention

Reduced rates of lung cancer have been observed in several occupational groups exposed to high levels of organic dusts contaminated by endotoxin. The underlying anti-neoplastic mechanism of endotoxin may be an increased secretion of endogenous anti-neoplastic mediators and activation of the toll-like receptors (TLR). A detoxified endotoxin derivative, Monophosphoryl Lipid A (MPL(®)) is marketed in Europe since 1999 as part of the adjuvant systems in allergy vaccines for treatment of allergic rhino-conjunctivitis and allergic asthma. Over 200,000 patients have used them to date (nearly 70% in Germany). Since detailed exposure (MPL(®) dose and timing of administration) and individual data are potentially available, an observational follow-up study could be conducted in Germany to investigate the protective effect of MPL(®) against cancer, comparing cancer incidence in two groups of patients with allergic rhinitis: those treated with allergoids plus MPL(®) and those treated with a vaccine including the same allergoids but not MPL(®). The protective effect of MPL(®) could be quantified in ever and never smokers. If this proposed observational study provides evidence of protective effects, MPL(®) could be immediately used as a chemo-preventive agent since it is already in use as adjuvant in human vaccines against cancer.

Pollinex Quattro: an innovative four injections immunotherapy in allergic rhinitis

The prevalence of seasonal allergic rhinitis in the western world is high and increasing. Besides considerably affecting physical and psychosocial aspects of patients' lives, allergic rhinitis is often associated with allergic asthma and may aggravate this condition over time. Specific immunotherapy is currently the only approved therapy that can modify the underlying disease process and induce long-term tolerance to allergens. Pollinex Quattro is a subcutaneous four injections immunotherapy consisting of tyrosine-absorbed specific allergoids and enhanced with the adjuvant monophosphoryl lipid A (MPL(®)). MPL(®) induces a significant Th 1-type immune response, characterized by an increase of allergen-specific IgG antibody levels and dampening of the IgE response during allergen exposure. Due to this dual action of stimulating the immune system, Pollinex Quattro is clinically effective after only four injections given pre-seasonally. A large clinical program has demonstrated efficacy and tolerability of Pollinex Quattro in children, adolescents and adults with grass and tree pollen allergy. A health economics study concluded that an immunotherapy with only 4 injections might be more cost-beneficial than other application forms of immunotherapy.

Allergen-specific immunotherapy of allergy and asthma: current and future trends

Allergen-specific immunotherapy is the only immunomodulatory and etiological therapy of allergy and asthma. Conventional specific immunotherapy (SIT) with whole-allergen extract is antigen specific, effective on multiple organs, efficient on asthma in defined conditions, provides long-lasting protection and is cost effective. Moreover, SIT is able to prevent the course of rhinitis to asthma. SIT has its drawbacks: the long duration of treatment, the unsatisfactory standardization of allergen extracts and a questionable safety level. Novel approaches are aimed at drastically reducing adverse anaphylactic events, shortening the duration of therapy and improving its efficacy. Novel promising approaches have based their formulation on a limited set of recombinant allergens or chimeric molecules as well as on hypoallergenic allergen fragments or peptides. The simultaneous use of adjuvants with immunomodulatory properties may contribute to improve both the safety and efficacy of allergen-SIT of allergy and asthma.

Anti-inflammatory effects of pre-seasonal Th1-adjuvant vaccine to Parietaria judaica in asthmatics

Background:

The ultra-short course pre-seasonal allergy vaccine, containing appropriate allergoids with the adjuvant monophosphoryl lipid A (MPL), may be effective in treating allergic symptoms.

Objective:

To explore the timing of the immunological responses to the pre-seasonal allergy vaccine.

Methods:

Four subcutaneous injections of the active product (Pollinex Quattro) were administered to 20 Parietaria-sensitive intermittent asthmatics (M/F: 12/8; age: 48 ± 10 years; FEV₁% predicted: 108% ± 12%) during the 6 weeks prior to the start of the pollen season. Exhaled breath condensate (EBC) was collected immediately before the first and immediately after the last injections (t₁ and t₂), during the pollen season (t₃) and after (t₄) the pollen season. EBC was analyzed to determine the levels of pH and 8-isoprostane. Ten Parietaria-sensitive asthmatics served as the untreated control group at t₁ and t₂.

Results:

Measured pH levels were 7.64 ± 0.33 at t₁, 7.67 ± 0.23 at t₂, 7.72 ± 0.34 at t₃, and 7.82 ± 0.34 at t₄ (P = 0.049 vs baseline). 8-isoprostane levels were significantly lower than baseline at each visit (mean difference from baseline, for t₂: −0.77 pg, P = 0.031; for t₃: −0.92 pg, P = 0.010; for t₄: −0.70 pg, P = 0.048). In the control group, pH levels were 7.73 ± 0.26 at baseline and did not change after 6 weeks (7.79 ± 0.25, P = 0.33). Similarly, the concentrations of 8-isoprostane in the control group were not different from those of the study group at baseline (P = 0.86), and the levels remained unchanged after 6 weeks (P = 0.58).

Conclusion:

These findings show that the ultra-short course of vaccine adjuvated with MPL acutely reduces the degree of airway inflammation, as expressed by markers of oxidative stress, and suggest that this reduction is maintained during and after the pollen season.

Immunomodulatory nanoparticles as adjuvants and allergen-delivery system to human dendritic cells: Implications for specific immunotherapy

Novel adjuvants and antigen-delivery systems with immunomodulatory properties that shift the allergenic Th2 response towards a Th1 or regulatory T cell response are desired for allergen-specific immunotherapy. This study demonstrates that 200-nm sized biodegradable poly(gamma-glutamic acid) (gamma-PGA) nanoparticles (NPs) are activators of human monocyte-derived dendritic cells (MoDCs). Gamma-PGA NPs are efficiently internalized by immature MoDCs and strongly stimulate production of chemokines and inflammatory cytokines as well as up-regulation of co-stimulatory molecules and immunomodulatory mediators involved in efficient T cell priming. Furthermore, MoDCs from allergic subjects stimulated in vitro with a mixture of gamma-PGA NPs and extract of grass pollen allergen Phleum pratense (Phl p) augment allergen-specific IL-10 production and proliferation of autologous CD4(+) memory T cells. Thus, gamma-PGA NPs are promising as sophisticated adjuvants and allergen-delivery systems in allergen-specific immunotherapy.

Ultra-short course immunotherapy in children and adolescents during a 3-yrs post-marketing surveillance study

Ultra-short course immunotherapy (uSCIT) has shown good efficacy and tolerability in children and adolescents with seasonal allergic rhinitis (SAR), conjunctivitis and/or asthma in clinical studies. Here, we investigate the efficacy of uSCIT in the juvenile subpopulation of a 3-year post-marketing surveillance (PMS) study. To assess the differences in the efficacy of uSCIT between adults and children respectively adolescents enrolled in a PMS study. In a prospective open study 422 patients aged 6-18 years with SAR, conjunctivitis and/or asthma received four pre-seasonal injections with pollen allergoids formulated with monophosphoryl lipid A (MPL, Pollinex Quattro) over a minimum of 3 weeks. Efficacy was evaluated by response to therapy and consumption of anti-allergic medication during the pollen season. Tolerability was evaluated by patients' acceptance of therapy. These results were compared with the adult subpopulation of this study. Response to treatment was assessed as good or very good in 94% of patients, mirroring findings for the entire cohort. Further improvements were noted in patients receiving subsequent courses of therapy. Anti-allergic medication use decreased from 83% to 24% of patients after the first treatment course (p < 0.0001). Therapy was well accepted by children/adolescents and considered 'very good' or 'good' by 93% of juveniles. No serious adverse events or cases of anaphylaxis were reported. This subanalysis indicated that uSCIT with Pollinex Quattro had similar efficacy and tolerability in children/adolescents and adults. The convenient dosing regimen and favourable safety profile of uSCIT may support a wider uptake of uSCIT in this patient population.

Pollinex Quattro Tree: allergy vaccine

An overview of short-term specific immunotherapy (ST-SIT) highlighting Pollinex Quattro (PQ) Tree is presented. The product development of this novel allergy vaccine using modifying agent glutaraldehyde, adjuvant monophosphoryl lipid and L-tyrosine have heralded a superior ST-SIT. Since 1999 when PQ was founded in Germany, various research trials assessing both the standardization and clinical studies have been done. A review of these studies demonstrates the efficacy and safety of PQ Tree in both pediatric and adult trials. The uniqueness of this product allows a shorter course of four pre-seasonal injections to provide control of allergy symptomatology in seasonal rhinitis patients. The PQ Tree product studies show a similar efficacy and safety profile to the grass formulation trial.

Update on toll-like receptor-directed therapies for human disease

Innate responses to microbes are mediated in large part by toll-like receptors (TLRs), which recognise a diverse range of molecules produced by viruses, bacteria and fungi. Great effort has been directed towards translating this knowledge into the development of new therapies for a wide spectrum of diseases, including infectious, malignant, autoimmune and allergic diseases. This review will provide a brief update on completed, ongoing and planned clinical trials of TLR ligand-based therapies for the treatment of diseases in humans.

The clinical grade maturation cocktail monophosphoryl lipid A plus IFNgamma generates monocyte-derived dendritic cells with the capacity to migrate and induce Th1 polarization

Ex vivo generated monocyte-derived dendritic cells (DCs) are used as a cellular vaccine against cancer in clinical trials. In order to be able to induce an efficient tumour-specific CTL response during immunotherapy, DCs have to be able to migrate to the lymph node and produce the Th1 polarizing cytokine, IL-12p70, upon encounter of T cells in the lymph node. However, most clinically used DCs do not produce IL-12p70 upon T cell contact. In this study, we compared a newly developed clinical grade DC maturation cocktail consisting of MPLA and IFNgamma with two clinically available maturation cocktails, the 'gold standard' (TNFalpha, IL-1beta, IL-6 and PGE(2)) and the 'alpha type 1 polarizing' (TNFalpha, IL-1beta, IFNalpha, IFNgamma and pI:C) cocktail. All three cocktails induced phenotypically mature DCs. However, in contrast to 'gold standard' DCs, which produce no IL-12p70 and as a result induce mainly Th2 cells, DCs matured with MPLA and IFNgamma produce high levels of IL-12p70 upon CD40 triggering. Subsequently, these DCs induce mainly Th1 cells in vitro, even slightly more than by the alpha type 1 polarized DCs. In addition, MPLA plus IFNgamma matured DCs have an intermediate migratory capacity towards CCL21. In conclusion, we here present MPLA plus IFNgamma as a simple clinical grade maturation cocktail to generate immunostimulatory DCs with superior capacity to induce type 1 immunity.

Lipopolysaccharide analogs improve efficacy of acellular pertussis vaccine and reduce type I hypersensitivity in mice

Pertussis is an infectious disease of the respiratory tract that is caused by the gram-negative bacterium Bordetella pertussis. Although acellular pertussis (aP) vaccines are safe, they are not fully effective and thus require improvement. In contrast to whole-cell pertussis (wP) vaccines, aP vaccines do not contain lipopolysaccharide (LPS). Monophosphoryl lipid A (MPL) and Neisseria meningitidis LpxL2 LPS have been shown to display immune-stimulating activity while exerting little endotoxin activity. Therefore, we evaluated whether these LPS analogs could increase the efficacy of the aP vaccine. Mice were vaccinated with diphtheria-tetanus-aP vaccine with aluminum, MPL, or LpxL2 LPS adjuvant before intranasal challenge with B. pertussis. Compared to vaccination with the aluminum adjuvant, vaccination with either LPS analog resulted in lower colonization and a higher pertussis toxin-specific serum immunoglobulin G level, indicating increased efficacy. Vaccination with either LPS analog resulted in reduced lung eosinophilia, reduced eosinophil numbers in the bronchoalveolar lavage fluid, and the ex vivo production of interleukin-4 (IL-4) by bronchial lymph node cells and IL-5 by spleen cells, suggesting reduced type I hypersensitivity. Vaccination with either LPS analog increased serum IL-6 levels, although these levels remained well below the level induced by wP, suggesting that supplementation with LPS analogs may induce some reactogenicity but reactogenicity considerably less than that induced by the wP vaccine. In conclusion, these results indicate that supplementation with LPS analogs forms a promising strategy that can be used to improve aP vaccines.

Translational mini-review series on Toll-like receptors: Toll-like receptor ligands as novel pharmaceuticals for allergic disorders

Characterization of the Toll-like receptor (TLR) family and associated signalling pathways provides a key molecular basis for our understanding of the relationship between exposure to microbial products and susceptibility to immune-mediated disorders. Indeed, ligation of TLR controls innate and adaptive immune responses by inducing synthesis of pro- as well as anti-inflammatory cytokines and activation of effector as well as regulatory lymphocytes. TLRs are therefore considered as major targets for the development of vaccine adjuvants, but also of new immunotherapies. Herein, we review the potential of TLR ligands as a novel class of pharmaceuticals for the prevention or treatment of allergic disorders.