Immunotherapy with Alpare in patients with respiratory allergy to Parietaria pollen: a two year double-blind placebo-controlled study

Tolerability and positive efficacy results after subcutaneous immunotherapy with Parietaria judaica depot extract

AIM

To evaluate tolerability and efficacy of Parietaria judaica subcutaneous immunotherapy on patients with allergic rhinoconjunctivitis.

PATIENTS & METHODS

51 patients were assigned to build-up scheme (six increasing doses) of P. judaica depot native extract, plus three maintenance monthly administrations.

RESULTS

Out of 470 administered doses, only 3.8% elicited systemic reactions (1.5% nonspecific and 2.3% grade I). Concerning the exploratory efficacy parameters: cutaneous reactivity at the final visit versus baseline was significantly decreased; specific titers of IgG and IgG4 increased significantly and patients showed a significant decrease in the rhinitis symptoms score.

CONCLUSION

P. judaica subcutaneous immunotherapy (Allergovac^® depot ROXALL Medicina España S.A., Zamudio, Spain) with an abbreviated up-dosing scheme showed an adequate safety and tolerability profile and induced preliminary efficacy changes.

Parietaria Allergy: An Intriguing Challenge for the Allergist

Parietaria pollen is the most important cause of pollen allergies in the Mediterranean area, as Parietaria is widespread in this region. Many issues are associated with Parietaria allergy, including the duration of the pollen season (many doctors in fact believe that it lasts throughout the year), pollen load (which seems to be increasing over time), the impact of age (on IgE production and symptom severity), inflammatory changes (after pollen exposure), and the choice of allergen immunotherapy (AIT). In addition, molecular diagnostics allows for the defining of a correct diagnosis, differentiating between mere sensitization and true allergy. This review considers these topics and will hopefully help the allergist in clinical practice. Parietaria allergy is an intriguing challenge for the allergist in clinical practice, but it may be adequately managed by knowing the peculiarities of respective territories and the clinical characteristics of each patient.

Local reactions from subcutaneous allergen immunotherapy

Local reactions from subcutaneous allergen immunotherapy are very common during the course of immunotherapy. These local reactions are not bothersome to patients. Local reactions from immunotherapy also do not predict future local or systemic reactions. This review discusses the studies that show that local reactions are not predictive of future reactions and that dose adjustments for local reactions from allergen immunotherapy are unnecessary. The article also focuses on factors that lead to patient noncompliance with immunotherapy and evaluates methods to prevent local reactions from subcutaneous allergen immunotherapy.

Injection allergen immunotherapy for asthma

BACKGROUND

Allergen specific immunotherapy has long been a controversial treatment for asthma. Although beneficial effects upon clinically relevant outcomes have been demonstrated in randomised controlled trials, there remains a risk of severe and sometimes fatal anaphylaxis. The recommendations of professional bodies have ranged from cautious acceptance to outright dismissal. With increasing interest in new allergen preparations and methods of delivery, we updated the systematic review of allergen specific immunotherapy for asthma.

OBJECTIVES

The objective of this review was to assess the effects of allergen specific immunotherapy for asthma.

SEARCH STRATEGY

We searched the Cochrane Airways Group Trials Register up to 2005, Dissertation Abstracts and Current Contents.

SELECTION CRITERIA

Randomised controlled trials using various forms of allergen specific immunotherapy to treat asthma and reporting at least one clinical outcome.

DATA COLLECTION AND ANALYSIS

Three authors independently assessed eligibility of studies for inclusion. Two authors independently performed quality assessment of studies.

MAIN RESULTS

Eighty-eight trials were included (13 new trials). There were 42 trials of immunotherapy for house mite allergy; 27 pollen allergy trials; 10 animal dander allergy trials; two Cladosporium mould allergy, two latex and six trials looking at multiple allergens. Concealment of allocation was assessed as clearly adequate in only 16 of these trials. Significant heterogeneity was present in a number of comparisons. Overall, there was a significant reduction in asthma symptoms and medication, and improvement in bronchial hyper-reactivity following immunotherapy. There was a significant improvement in asthma symptom scores (standardised mean difference -0.59, 95% confidence interval -0.83 to -0.35) and it would have been necessary to treat three patients (95% CI 3 to 5) with immunotherapy to avoid one deterioration in asthma symptoms. Overall it would have been necessary to treat four patients (95% CI 3 to 6) with immunotherapy to avoid one requiring increased medication. Allergen immunotherapy significantly reduced allergen specific bronchial hyper-reactivity, with some reduction in non-specific bronchial hyper-reactivity as well. There was no consistent effect on lung function. If 16 patients were treated with immunotherapy, one would be expected to develop a local adverse reaction. If nine patients were treated with immunotherapy, one would be expected to develop a systemic reaction (of any severity).

AUTHORS' CONCLUSIONS

Immunotherapy reduces asthma symptoms and use of asthma medications and improves bronchial hyper-reactivity. One trial found that the size of the benefit is possibly comparable to inhaled steroids. The possibility of local or systemic adverse effects (such as anaphylaxis) must be considered.

Treatment of congestion in upper respiratory diseases

Congestion, as a symptom of upper respiratory tract diseases including seasonal and perennial allergic rhinitis, acute and chronic rhinosinusitis, and nasal polyposis, is principally caused by mucosal inflammation. Though effective pharmacotherapy options exist, no agent is universally efficacious; therapeutic decisions must account for individual patient preferences. Oral H₁-antihistamines, though effective for the common symptoms of allergic rhinitis, have modest decongestant action, as do leukotriene receptor antagonists. Intranasal antihistamines appear to improve congestion better than oral forms. Topical decongestants reduce congestion associated with allergic rhinitis, but local adverse effects make them unsuitable for long-term use. Oral decongestants show some efficacy against congestion in allergic rhinitis and the common cold, and can be combined with oral antihistamines. Intranasal corticosteroids have broad anti-inflammatory activities, are the most potent long-term pharmacologic treatment of congestion associated with allergic rhinitis, and show some congestion relief in rhinosinusitis and nasal polyposis. Immunotherapy and surgery may be used in some cases refractory to pharmacotherapy. Steps in congestion management include (1) diagnosis of the cause(s), (2) patient education and monitoring, (3) avoidance of environmental triggers where possible, (4) pharmacotherapy, and (5) immunotherapy (for patients with allergic rhinitis) or surgery for patients whose condition is otherwise uncontrolled.

Allergen injection immunotherapy for seasonal allergic rhinitis

BACKGROUND

Allergic rhinitis is the most common of the allergic diseases. Despite improved understanding of the pathophysiology of allergic rhinitis and advances in its pharmacological treatment, its prevalence has increased worldwide. For patients whose symptoms remain uncontrolled despite medical treatment, allergen injection immunotherapy is advised. An allergen-based treatment may reduce symptoms, the need for medication and modify the natural course of this disease.

OBJECTIVES

To evaluate the efficacy and safety of subcutaneous specific allergen immunotherapy, compared with placebo, for reducing symptoms and medication requirements in seasonal allergic rhinitis patients.

SEARCH STRATEGY

We searched the Cochrane Ear, Nose and Throat Disorders Group Trials Register, the Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library, Issue 1 2006), MEDLINE (1950 to 2006), EMBASE (1974 to 2006), Pre-MEDLINE, KOREAMED, INDMED, LILACS, PAKMEDINET, Scisearch, mRCT and the National Research Register. The date of the last search was February 2006.

SELECTION CRITERIA

All studies identified by the searches were assessed to identify randomised controlled trials involving participants with symptoms of seasonal allergic rhinitis and proven allergen sensitivity, treated with subcutaneous allergen specific immunotherapy or corresponding placebo.

DATA COLLECTION AND ANALYSIS

Two independent authors identified all studies reporting double-blind, placebo controlled randomised trials of specific immunotherapy in patients with seasonal allergic rhinitis due to tree, grass or weed pollens. Two authors independently performed quality assessment of studies. Data from identified studies were abstracted onto a standard extraction sheet and subsequently entered into RevMan 4.2.8. Analysis was performed using the Standardised Mean Difference (SMD) method and a random-effects model; P values < 0.05 were considered statistically significant. The primary outcome measures were symptom scores, medication use, quality of life and adverse events.

MAIN RESULTS

We retrieved 1111 publications of which 51 satisfied our inclusion criteria. In total there were 2871 participants (1645 active, 1226 placebo), each receiving on average 18 injections. Duration of immunotherapy varied from three days to three years. Symptom score data from 15 trials were suitable for meta-analysis and showed an overall reduction in the immunotherapy group (SMD -0.73 (95% CI -0.97 to -0.50, P < 0.00001)). Medication score data from 13 trials showed an overall reduction in the immunotherapy group (SMD of -0.57 (95% CI -0.82 to -0.33, p<0.00001)). Clinical interpretation of the effect size is difficult. Adrenaline was given in 0.13% (19 of 14085 injections) of those on active treatment and in 0.01% (1 of 8278 injections) of the placebo group for treatment of adverse events. There were no fatalities.

AUTHORS' CONCLUSIONS

This review has shown that specific allergen injection immunotherapy in suitably selected patients with seasonal allergic rhinitis results in a significant reduction in symptom scores and medication use. Injection immunotherapy has a known and relatively low risk of severe adverse events. We found no long-term consequences from adverse events.

Allergen immunotherapy for asthma

BACKGROUND

Allergen specific immunotherapy has long been a controversial treatment for asthma. Although beneficial effects upon clinically relevant outcomes have been demonstrated in randomised controlled trials, there remains a risk of severe and sometimes fatal anaphylaxis. The recommendations of professional bodies have ranged from cautious acceptance to outright dismissal. With increasing interest in new allergen preparations and new methods of delivery, it was time to conduct another systematic review of allergen specific immunotherapy for asthma.

OBJECTIVES

The objective of this review was to assess the effects of allergen specific immunotherapy for asthma.

SEARCH STRATEGY

We searched the Cochrane Airways Group trials register up to June 2001, MEDLINE, Dissertation Abstracts, Current Contents and reference lists of articles.

SELECTION CRITERIA

Randomised controlled trials using various forms of allergen specific immunotherapy to treat asthma and reporting at least one clinical outcome.

DATA COLLECTION AND ANALYSIS

Three reviewers independently assessed eligibility of studies for inclusion. Two reviewers independently performed quality assessment of studies.

MAIN RESULTS

Seventy-five trials were included (52 of 54 previously included trials and 23 new trials). A total of 3,506 participants (3,188 with asthma) were involved. There were 36 trials of immunotherapy for house mite allergy; 20 pollen allergy trials; ten animal dander allergy trials; two Cladosporium mould allergy, one latex and six trials looking at multiple allergens. Concealment of allocation was assessed as clearly adequate in only 15 of these trials. Significant heterogeneity was present in a number of comparisons. Overall, there was a significant reduction in asthma symptoms and medication and improvement in bronchial hyper-reactivity following immunotherapy. There was a significant improvement in asthma symptom scores (standardised mean difference -0.72, 95% confidence interval -0.99 to -0.33) and it would have been necessary to treat 4 (95%CI 3 to 5) patients with immunotherapy to avoid one deterioration in asthma symptoms. Overall it would have been necessary to treat 5 (95%CI 4 to 6) patients with immunotherapy to avoid one requiring increased medication. Allergen immunotherapy significantly reduced allergen specific bronchial hyper-reactivity, with some reduction in non-specific bronchial hyper-reactivity as well. There was no consistent effect on lung function.

REVIEWER'S CONCLUSIONS

Immunotherapy reduces asthma symptoms and use of asthma medications and improves bronchial hyper-reactivity. One trial found that the size of the benefit is possibly comparable to inhaled steroids. The possibility of adverse effects (such as anaphylaxis) must be considered.

Immunotherapy for allergic asthma

Specific allergen immunotherapy is an effective treatment of allergic asthma. Double-blind studies provide proof of benefit, although seasonal or intermittent asthma consistently responds better than perennial asthma. Advantages of immunotherapy compared with most pharmacotherapies include modification of the natural history of allergic disease, reduction of need for chronic medication, and treatment of both upper and lower airway disease simultaneously. Improvements in immunotherapy occurred in the later portion of the twentieth century because of enhanced understanding of immunotherapy's mechanism of action, recognition of the dose effect, and improved quality and consistency of allergen vaccines. Purified inhibitors of specific mediators of the allergic response, products of biotechnology, will probably lead to improvements of immunotherapy of asthma in the twenty-first century. The future of immunotherapy and other immunomodulation of allergic asthma is promising.

The safety and efficacy of subcutaneous birch pollen immunotherapy - a one-year, randomised, double-blind, placebo-controlled study

BACKGROUND

There is only very limited documentation of the efficacy and safety of high-dose subcutaneous birch pollen immunotherapy (IT) in double-blind, placebo-controlled (DBPC) studies. Birch pollen is a major cause of allergic morbidity in northern Europe and in eastern parts of North America.

METHODS

Thirty-five patients with severe rhinoconjunctivitis (hay fever) to birch pollen were allocated to double-blinded clustered IT with a depot birch pollen extract (Betula verrucosa) or placebo injections. Seven patients in each group had concomitant self-reported seasonal asthma. Treatment was conducted as a clustered regimen and was performed in a specialist unit. Symptom scores from nose, eyes, and lungs, and use of oral and topical antihistamines, beta-2-agonists, and oral corticosteroids were recorded daily during the season of 2000. Sensitivity to allergen provocation in skin, conjunctiva, and nasal mucosa was measured before and after 10 months of treatment. Post-seasonal assessment of symptom severity was performed using a simple questionnaire.

RESULTS

IT reduced the symptom score for both rhinoconjunctivitis and asthma (P-values < 0.05), total medication score (P < 0.02) and use of oral antihistamines (P < 0.01). IT reduced specific conjunctival sensitivity (P < 0.05), skin prick test, and especially cutaneous late-phase response diameters (P < 0.00001), and increased general well-being on post-seasonal evaluation (P < 0.01). IT was safe, with side-effects at the same level as placebo.

CONCLUSIONS

High-dose, subcutaneous IT is efficacious and safe in patients with severe birch pollen rhinoconjunctivitis and asthma.

Local and systemic reactions during immunotherapy with adsorbed extracts of house dust mite in children

BACKGROUND

We retrospectively evaluated the incidence of local and systemic reactions to injections of adsorbed extracts of house dust mites (Dermatophagoides pteronyssinus and Dermatophagoides farinae) applied according to a conventional schedule in children.

METHOD

Eighty-eight patients aged 6 to 15 years, suffering from allergic asthma or asthma together with rhinitis, at various stages of treatment with immunotherapy from January 1989 to November 1997 were included.

RESULTS

Out of 5,760 injections, 5,542 (96.21%) were not associated with a reaction, 206 injections (3.57%) caused local reactions (144, <20 mm in diameter; 62, >20 mm), and systemic reactions were seen after 12 injections (0.2%). Twelve patients experienced 12 systemic reactions. Of these, 7 patients (58.3%) experienced no local reactions prior to a systemic reaction. Eleven males and one female had systemic reactions. Most of both local and systemic reactions occurred within less than 30 minutes after the injection.

CONCLUSIONS

Our study supports the safety of immunotherapy with house dust mites in children. The majority of reactions were local. Although five of 12 patients who experienced systemic reactions had local reactions prior to a systemic reaction, in general the presence of local reactions was not helpful in predicting which patients would develop systemic reactions. Males and patients with asthma together with rhinitis appeared to be at greater risk for systemic reactions.

A double-blind, placebo-controlled trial of local nasal immunotherapy in allergic rhinitis to Parietaria pollen

We assessed the efficacy and safety of local nasal immunotherapy (LNIT) using an extract in macronized powder form of Parietaria pollen, a very important allergenic plant in the Mediterranean and other parts of the world. Twenty-six patients aged 13-37 years, with seasonal allergic rhinitis to this pollen, were enrolled in a double-blind placebo-controlled trial, carried out from autumn 1991 to the end of June 1992. They were selected on the basis of a positive skin-prick test, radioallergosorbent test (RAST) and intranasal challenge to Parietaria antigen. Patients were randomly divided into two groups of 13; the first group was given Parietaria antigen, and the second placebo. We recorded mean weekly symptom scores and drug consumption for 17 weeks during the pollen season in the year 1992, and specific serum-IgE and IgG levels. Three patients in the active group withdrew from the study because of bronchial symptoms. A significant difference was observed in mean weekly nasal symptom scores, in drug consumption and in specific nasal threshold to Parietaria allergenic extract in the treated and control groups. No difference was observed in serum IgE and IgG levels. Serum IgE levels rose significantly only in the control group after the pollen season. This study indicates that LNIT may be a useful alternative to traditional subcutaneous immunotherapy in patients with allergic rhinitis.