Double-blind, placebo-controlled rush immunotherapy with a standardized Alternaria extract

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 with an oral Alternaria extract in childhood asthma. Clinical safety and efficacy and effects on in vivo and in vitro parameters]

Studies of immunotherapy with oral Alternaria extracts are scarce. We decided to perform a clinical trial of the clinical safety and efficacy of this extract as well as of its effects on in vivo and in vitro parameters in 39 patients with Alternaria allergy, aged between 7 and 17 years, who are also sensitized extract was used. Allergic activity was determined through RAST inhibition and skin prick test. Quantification of the principal allerten (Alt a 1) was performed through the 2-site binding assay, with a mean content of 34.2 ng Alt a 1/micro g protein. The parameters analyzed were the symptom-medication score, skin prick using the end-point technique, specific bronchial challenge test, peak flow, total and specific IgE and IgG4. Nineteen patiens received active treatment with oral immunotherapy and another 19 received symptomatic treatment. The initial phase of immunotherapy lasted 3 months until the maximum dose was reached. This was maintained for 12 months; the mean accumulated dos was 280,000 PNU. Significant differences were found in reduction in the symptom-medication score in the treated group after 12 months of immunotherapy. No differences were found in the control group. Immunotherapy was well tolerated with 0.42 adverse reactions per 100 doses administered. All adverse reactions were mild-to-moderate. In the treated group, papule size was significantly reduced. Values for the specific bronchial challenge test, expressed through PD20, were significantly higher in the immunotherapy group. Peak flow showed no changes in either group. Values of IgG4 were significantly higher in the immunotherapy group. Total and specific IgE levels showed no significant changes in either group. In conclusion, oral immunotherapy with Alternaria extract is clinically effective in pediatric patients. In general, the therapy was well tolerated. It modified specific cutaneous and bronchial reactivity in our sample and increased levels of specific IgG4, wich are implicated in humoral response.

Current opinion of immunotherapy for ocular allergy

PURPOSE OF REVIEW

Allergic conjunctivitis is common and may be the most prominent or the only feature of allergies. Immunotherapy has been used as a primary treatment for allergies since the early 1900s. Currently the use of immunotherapy for allergic rhinoconjunctivitis is well established and has been shown to decrease the development of bronchial hyperreactivity and asthma. However, the role of immunotherapy for primary treatment of allergic conjunctivitis is unclear. We reviewed the studies where immunotherapy was used with particular attention to the affects on ocular allergies.

RECENT FINDINGS

There are many schedules and methods of delivering immunotherapy. Recent studies have started to assess ocular symptoms as one of the parameters to monitor efficacy of therapy. They follow the affects of immunotherapy on conjunctival provocation tests, ocular symptoms, or the use of eye drops. The literature suggests that using the various immunotherapy modalities at different schedules, ocular symptoms improved even when immunotherapy was used on a rush schedule.

SUMMARY

The initiation of immunotherapy for allergic rhinoconjunctivitis has been shown to switch the immune response to T helper 1 and thus avoid the progression of other atopic conditions. Current literature shows that using many allergens with different forms of immunotherapy appear to have a significant improvement in ocular allergy symptoms and this can be achieved rapidly and safely in most patients. Whether using immunotherapy early in allergic conjunctivitis will alter the progression of other atopic conditions remains to be investigated.

Immunotherapy for inhalant allergies. Guidelines for why, when, and how to use this treatment

Great-grandma was probably on the right track when she said, "A little dirt won't hurt you. It builds immunity." In fact, some evidence suggests that our "hygienic" environment may be increasing our vulnerabilities to some maladies, especially allergic disorders. Although the principles of immunotherapy have been known for nearly a century, guidelines for its use are still evolving. In this article, Dr Portnoy discusses the role of immunotherapy in patients with symptoms triggered by airborne allergens.

Preliminary description of antigenic components characteristic of Stachybotrys chartarum

The objective of this study was to characterize preliminarily immunogenic components characteristic of Stachybotrys chartarum to be used later for the development of a detection method for the fungus in environmental samples. The procedure for S.chartarum extract preparation was first optimized related to the age of the culture, culture type, and growth medium, and the antigenic composition of S. chartarum cultured in two different media was then characterized by the sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) and immunoblotting method. Cross-reactivity of S. chartarum antigenic components with 10 other fungal species was identified by the inhibition immunoblotting method. The 10-day-old S. chartarum culture extract cultured in malt extract broth revealed a wider selection of proteins and antigenic components than the 30-day-old culture extract or the culture medium extracts. When cultured in cellulose broth, S. chartarum produced a higher number of proteins and antigenic components than in malt extract broth. The most dominant immunogenic components of S. chartarum cultured in cellulose broth were those of 65, 50, 37, and 27 kDa. The components of 65 and 50 kDa proved to be the most characteristic of this fungus according to the inhibition immunoblotting analyses. Several of the S. chartarum components were identified as glycoproteins. Carbohydrate moieties of the S. chartarum components also possessed an antibody binding activity.

Evaluation of the safety of an abbreviated course of injections of allergen extracts (rush immunotherapy) for the treatment of dogs with atopic dermatitis

OBJECTIVE

To evaluate the safety of an abbreviated course of injections of allergen extracts (rush immunotherapy) for the treatment of dogs with atopic dermatitis.

ANIMALS

30 dogs with atopic dermatitis examined at a veterinary dermatology referral practice for treatment with allergen-specific immunotherapy.

PROCEDURE

A catheter was placed in a vein in each dog. Dogs were constantly observed throughout the procedure. Allergen extracts were administered in increasing concentrations every 30 minutes for 6 hours to a maintenance concentration of 20,000 protein nitrogen units/ml. Epinephrine, oxygen, and emergency treatment were available as needed.

RESULTS

In 22 (73%) dogs, rush immunotherapy safely replaced the prolonged induction period (15 weeks) of weekly injections that consists of increasing concentrations of allergen extract. In 7 (23%) dogs, the induction period was abbreviated to 4 weeks. Of the 8 dogs that developed problems during rush immunotherapy, increased pruritus necessitated premature cessation of rush immunotherapy in 7, and 1 developed generalized wheals. Oral administration of prednisolone (1 mg/kg of body weight) resulted in resolution of adverse effects in all 8 dogs.

CONCLUSION AND CLINICAL RELEVANCE

Rush immunotherapy performed by personnel at a veterinary hospital is a safe method for treatment of dogs with atopic dermatitis.

Effectiveness of specific immunotherapy in the treatment of allergic rhinitis: an analysis of randomized, prospective, single- or double-blind, placebo-controlled studies

BACKGROUND

The effectiveness of specific immunotherapy (SIT) in the treatment of allergic rhinitis has been supported by empirical evidence and clinical experience.

OBJECTIVE

This report is an analysis of multiple studies involving patients with documented allergic rhinitis.

METHODS

All studies of the effectiveness of SIT in the treatment of allergic rhinitis published in English between the years 1966 and 1996 were identified through a MEDLINE search. All prospective, single- or double-blind, placebo-controlled studies were included in the analysis. One author (R.N.R.) extracted data from the studies. Odds ratios (ORs) and 95% confidence intervals (CIs) were calculated using a random-effects model for a variety of clinical measures in studies that permitted the extraction of numbers of patients with positive and negative outcomes.

RESULTS

Data were extracted from 16 studies of the clinical effectiveness of SIT in the treatment of allergic rhinitis, involving 759 patients (546 adults, 53 children, 160 all ages). In 15 (94%) of the studies, investigators concluded that SIT was effective. In the remaining study (the only one conducted in children), investigators concluded that SIT was not effective. Symptoms of allergic rhinitis were more likely to improve in patients receiving SIT than in the comparison patients (OR 1.81, 95% CI 1.48 to 2.23). Symptom-medication scores were significantly lower in patients receiving SIT than in the comparison patients in all studies using such measures (P < 0.05).

CONCLUSION

Results of this analysis support the conclusion that SIT is effective in the treatment of allergic rhinitis.

Economic evaluation of specific immunotherapy versus symptomatic treatment of allergic rhinitis in Germany

OBJECTIVE

To use published data to compare the economic consequences of specific immunotherapy (SIT) lasting 3 years with those of continuous symptomatic treatment in patients with either pollen or mite allergy.

DESIGN AND SETTING

The evaluation was conducted from the following 3 perspectives in Germany: (i) society; (ii) healthcare system; and (iii) statutory health insurance (SHI) provider. A modelling approach was used which was based on secondary analysis of existing data. The follow-up period was 10 years. The break-even point of cumulated costs, their difference per patient and the additional cost per additional patient free from asthma symptoms [incremental cost-effectiveness ratio (ICER)] were used as target variables, each from the viewpoint of SIT. The types of costs were direct and indirect (society), direct (healthcare system) and those incurred by SHI (i.e. expenses). In the base-case analysis, the average values of the clinical parameters and average case-related costs/expenses were applied.

MAIN OUTCOME MEASURES AND RESULTS

The break-even point was reached between year 6 and year 8 after the start of therapy, resulting in net savings of between 650 and 1190 deutschmarks (DM) per patient after 10 years. The ICERs of SIT were between -DM3640 and -DM7410, depending on study perspective and nature of the allergy (1990 values for symptomatic treatment and treatment of asthma, 1995 values for SIT; DM1 approximately $US0.58). The sensitivity analysis demonstrated the robustness of the model and its results. First, all the independent variables of the model were varied. Secondly, the influence of the model variables was quantified using a deterministic model. SIT was more likely to result in net savings than in additional costs. An economic parameter (cost for symptomatic treatment) had the highest influence on the results.

CONCLUSIONS

This evaluation showed that SIT for 3 years is economically advantageous in patients who are allergic to pollen or mites and whose symptoms are inadequately controlled by continuous symptomatic treatment. After 10 years, the administration of SIT leads to net savings from the perspectives of society, the healthcare system and SHI (third-party payer) in Germany.

Comparison between nasal provocation tests and skin tests in patients treated with loratadine and cetirizine

BACKGROUND

The effect of H1-blockers may differ depending on the target organ.

OBJECTIVE

A double-blind, placebo-controlled study was carried out to compare the effect of a 7-day treatment with loratadine (10 mg daily) or cetirizine (10 mg daily) on nasal challenge with grass pollen grains and skin tests with allergen or histamine.

METHODS

Twenty-four patients were enrolled, but the analysis was carried out on 23. Nasal challenge was carried out by using 5-fold increasing numbers of pollen grains. Skin prick tests were done with serial concentrations of allergens and 1 concentration of histamine. Patients were tested in a cross-over design, with each treatment being administered for the previous 7 days and with a 2-week washout period.

RESULTS

By comparison with placebo, loratadine and cetirizine increased significantly the threshold number of pollen grains required to induce a positive nasal challenge (P <.001). There was no difference between loratadine and cetirizine. Skin test responses to allergen were significantly reduced by loratadine and cetirizine by comparison with placebo. Skin test responses to histamine were significantly decreased by the 2 H1-blockers, but they were more profoundly decreased by cetirizine than by loratadine.

CONCLUSIONS

Both H1-blockers reduced similarly allergen-induced skin test and nasal challenge responses. Cetirizine was more effective on histamine skin test responses.

National guidelines needed to manage rhinitis and prevent complications

OBJECTIVES

Rhinitis is an extremely common disease worldwide and nasal allergies are one of the major causes of the condition. Allergic rhinitis not only produces a range of nasal and non-nasal symptoms, but it has been closely associated with other chronic airways diseases, such as asthma and sinusitis. This review was undertaken to evaluate the relationship of allergic rhinitis to these diseases and to provide support for proposing national guidelines for managing rhinitis.

DATA SOURCES

Relevant studies in English were searched for using MEDLINE, bibliographies from obtained articles, and consultation with experts.

STUDY SELECTION

All major studies related to the epidemiology and effects of allergic rhinitis and the relationship between allergic rhinitis and asthma, sinusitis, and other airways diseases were reviewed.

DATA SYNTHESIS

There is substantial scientific and clinical evidence that allergic rhinitis frequently coexists with asthma, and sinusitis and may be a predisposing factor for both. In addition, a number of studies have demonstrated that nasal inflammation and obstruction directly affect pulmonary function and clinical symptoms of asthma. Finally, it has been clearly demonstrated that treating allergic rhinitis with antihistamines, nasal corticosteroids, immunotherapy, and allergen avoidance have a significant, positive effect on lung function and asthma symptomology.

CONCLUSIONS

The prevalence of allergic rhinitis, asthma, and sinusitis are increasing. Asthma and sinusitis can be debilitating conditions. Asthma alone can be life threatening and costly to treat. The timely and optimal treatment of allergic rhinitis may help prevent these conditions or, at least, prevent them from worsening. Consequently, there is an immediate need to establish national, evidence-based, practice guidelines to assist primary care physicians in diagnosing and managing rhinitis and in evaluating and managing rhinitis and in evaluating and managing allergic rhinitis coexisting with other airways diseases.

Changes in skin-test reactivity do not correlate with clinical efficacy of H1-blockers in seasonal allergic rhinitis

New-generation H1-blockers may possess antiallergic properties, and their effect may differ, depending on the target organ. A double-blind, placebo-controlled, parallel-group study was carried out during the pollen season to compare the clinical effect on nasal and conjunctival symptoms of astemizole (10 mg o.d.) and loratadine (10 mg o.d.) with their effect on skin-test reactivity to allergen and histamine. Thirty-eight patients (12-56 years of age) were studied. Nasal and ocular symptoms were recorded daily from days 4 to 7. Skin prick tests with serial concentrations of allergens and one concentration of histamine were carried out before and at the end of the 7-day treatment period. Parallel-line bioassay, analysis of variance, and covariance were used to analyze skin test data. Loratadine and astemizole significantly decreased symptoms from baseline (P < 0.004 and P < 0.006). Skin-test reactivity to allergen and histamine was more profoundly decreased by astemizole than loratadine. The histamine covariant was more important in the allergen effect of astemizole than in that of loratadine. Two H1-blockers having the same clinical effect on nasal and ocular symptoms during the pollen season have totally different effects on skin-test reactivity. Skin-test reactivity to allergen or histamine is not predictive of the clinical efficacy of H1-blockers during seasonal allergic rhinitis.

A double-blind, placebo-controlled study of immunotherapy with grass-pollen extract Alutard SQ during a 3-year period with initial rush immunotherapy

Thirty patients with asthma and/or monosensitized allergic rhinitis caused by grass pollen whose ages ranged from 15 to 35 years were selected. Two groups were established at random: an active group and a placebo group, and a double-blind study was done on treatment with immunotherapy for a period of 3 continuous years, with initiation doses administered according to the rush immunotherapy technique. Grass-pollen allergen extract Alutard SQ and histamine as a placebo were used. The objective parameters of efficacy evaluated were end-point cutaneous tests, conjunctival provocation, bronchial provocation, and symptom/medication scores, as well as specific immunoglobulin determinations. The statistical evaluation of the results was significant for the differences existing between the initial and final time of the active group, and there were significant differences between the two groups for all of the parameters considered. We found no relationship between clinical improvement and the range of specific immunoglobulin E values. Regarding the safety of the treatment, systemic adverse effects were manifested only in the initial phase (rush immunotherapy), and were easily controlled by treatment. We conclude that the efficacy and safety of immunotherapy with grass pollen make it possible to consider this treatment fundamental in these patients.

Rush immunotherapy with house dust extract in patients with mild extrinsic asthma

Rush immunotherapy (RIT) with house dust extract was given to 15 patients with mild extrinsic or mixed asthma. Every patient was strongly positive for IgE on the radioimmunosorbent test and sensitive to house dust extract on the scratch skin test. Nine patients were positive on the bronchial provocation test to house dust extract and 6 could not be examined. All patients did not drop out and got to house dust extract solution 10(-1) within 1 week. The symptom-medication scores decreased significantly after RIT. During RIT 1 patient developed a mild asthmatic attack and 3 patients developed generalized skin reaction. Eight weeks later, the threshold for house dust-provoked bronchoconstriction increased in 9 patients, but did not in 3 patients. The blood eosinophil count and blood histamine level significantly decreased. We conclude that RIT is able to raise antigen concentrations for a short periods and effective but not risky for mild asthma.

Fungal allergens

Airborne fungal spores occur widely and often in far greater concentrations than pollen grains. Immunoglobulin E-specific antigens (allergens) on airborne fungal spores induce type I hypersensitivity (allergic) respiratory reactions in sensitized atopic subjects, causing rhinitis and/or asthma. The prevalence of respiratory allergy to fungi is imprecisely known but is estimated at 20 to 30% of atopic (allergy-predisposed) individuals or up to 6% of the general population. Diagnosis and immunotherapy of allergy to fungi require well-characterized or standardized extracts that contain the relevant allergen(s) of the appropriate fungus. Production of standardized extracts is difficult since fungal extracts are complex mixtures and a variety of fungi are allergenic. Thus, the currently available extracts are largely nonstandardized, even uncharacterized, crude extracts. Recent significant progress in isolating and characterizing relevant fungal allergens is summarized in the present review. Particularly, some allergens from the genera Alternaria, Aspergillus, and Cladosporium are now thoroughly characterized, and allergens from several other genera, including some basidiomycetes, have also been purified. The availability of these extracts will facilitate definitive studies of fungal allergy prevalence and immunotherapy efficacy as well as enhance both the diagnosis and therapy of fungal allergy.

Current trends in the management of allergic diseases

Treatment strategies for allergic diseases are based on allergen avoidance, pharmacotherapy and immunotherapy. Allergen avoidance should always be attempted, even if it is rarely complete and needs several days or weeks to be effective. Pharmacotherapy is aimed at reducing symptoms arising from allergen triggers and inflammation. In seasonal allergic diseases, a short treatment course is sufficient to reverse nonspecific hyperreactivity and symptoms. In chronic allergic diseases, however, inflammation is of major importance and symptoms are not always readily controlled. Moreover, the treatment should be prolonged as proposed by Guidelines for the Management of Asthma and Rhinitis (1, 2). Effective and well-tolerated drugs are now available and some may be combined for rhinitis or asthma therapy. In rhinitis, first-line therapy is still based on non-sedating antihistamines and topical corticosteroids. Cromoglycate and other drugs may also be used. For asthma, anti-inflammatory therapy is the first-line treatment. In mild sufferers, cromoglycate, nedocromil or low-dose inhaled steroids can be used. For more severe disease, high doses of inhaled corticosteroids are proposed. Bronchodilators are used as 'rescue' medications, though many patients with severe symptoms need regular bronchodilator therapy. Long-acting beta 2-agonists have been introduced recently, but their exact place in the management of asthma is not yet fully established. Immunotherapy was first introduced in 1911 and was based on decades of physicians' experience, rather than on rational thought. Standardized allergens have improved the efficacy of immunotherapy, but the safety of this treatment needs to be improved.(ABSTRACT TRUNCATED AT 250 WORDS)

Safety considerations in assessing the role of immunotherapy in allergic disorders

Specific immunotherapy (SIT) is accepted as an effective treatment of allergic diseases when high quality extracts are used. However, this form of treatment can cause untoward reactions among which systemic reactions are the most severe. Although life-threatening reactions are rare and deaths exceptionally reported, SIT should be prescribed by allergists to patients with well defined characteristics, and administered with care by (or under the close supervision of) physicians trained to deal rapidly with the reactions. Reactions with standardised extracts occur mostly during the dose increase phase but they can be prevented using adapted schedules and premedication. During maintenance injections or when vial batches are changed, standardised extracts of known shelf-life usually result in a low rate of systemic reactions. Patients with asthma are more prone to develop systemic reactions, and allergens should not be administered to patients with a forced expiratory volume in 1 second (FEV1) under 70% of predicted or in those who have unstable or symptomatic asthma. Systemic reactions may be observed with all allergens and allergenic preparations although it appears that high molecular weight extracts may be safer.

Injection immunotherapy. British Society for Allergy and Clinical Immunology Working Party

A working party of the British Society for Allergy and Clinical Immunology has reviewed the role of specific allergen immunotherapy in the treatment of allergic disease and produced a position statement summarising the available evidence for efficacy and safety. The working party recommends specific allergen immunotherapy for treating summer hay fever uncontrolled by conventional medication and for wasp and bee venom hypersensitivity. It is not recommended for asthma or for allergic rhinitis due to other allergens. For the recommended indications the risk:benefit ratio is acceptable provided patients are carefully selected; in particular, patients with asthma should be excluded as they are especially vulnerable to adverse reactions. Injections should be given only by doctors experiences in this form of treatment in a clinic where full resuscitative facilities are immediately available. Provided patients remain symptom free a 60 minute observation period after injection is sufficient to detect all serious adverse reactions.

The association of individual allergen reactivity with respiratory disease in a national sample: data from the second National Health and Nutrition Examination Survey, 1976-80 (NHANES II)

The independent association of individual allergen reactivity with respiratory disease was evaluated with use of the second National Health and Nutrition Examination Survey, a sample of the U.S. white civilian population, ages 6 to 24 years (n = 4295). Eight, 1:20 wt/vol, 50% glycerol, unstandardized extracts were administered by prick puncture. Allergen reactivity was reported as the percent with a mean erythema diameter 10.5 mm or greater at 20 minutes. Only the prevalence of asthma and allergic rhinitis increased with the increasing number of positive allergen skin tests. The independent association of individual allergen reactivity with respiratory disease was quantified with logistic models that included other allergen reactivity, age, sex, smoking, and region. Asthma was associated with reactivity to house dust (odds ratio, 2.9; 95% confidence interval [CI] 1.7 to 5) and Alternaria (odds ratio, 5.1; 95% CI: 2.9 to 8.9). Allergic rhinitis was associated with reactivity to ragweed (odds ratio, 2.3; 95% CI: 1.5 to 3.3); ryegrass (odds ratio, 2.8; 95% CI: 1.8 to 4.3); house dust (odds ratio, 2.5; 95% CI: 1.6 to 3.9); Alternaria (odds ratio, 2.3; 95% CI: 1.5 to 3.4). Asthma only (without allergic rhinitis) was associated with dust and Alternaria. Allergic rhinitis only (without asthma) was associated with ryegrass, ragweed, and house dust. When both asthma and allergic rhinitis were present, only house dust and Alternaria remained associated. These findings highlight the association of specific allergens with upper and lower respiratory diseases and the interactions among coexisting respiratory diseases.