Immunological effects and potential mechanisms of action of autologous serum therapy in chronic spontaneous urticaria.

BACKGROUND: Autoimmune processes are considered to play a major role in the pathogenesis of chronic spontaneous urticaria (CSU). Very recently, interleukin 24 (IL-24) has been identified as an immunoglobulin E (IgE) autoantigen in CSU. Some studies revealed that notably autologous serum skin test (ASST)-positive CSU patients may benefit from autohemotherapy; however, the mechanisms of action remain unknown. We aimed to investigate the immunological effects of autologous serum injections in ASST-positive CSU patients. METHODS: Sixty-six ASST-positive CSU patients were treated with weekly intramuscular autologous serum injections for 8 weeks and followed up for 12 weeks. Urticaria activity score (UAS7) and Dermatology Life Quality Index (DLQI) were assessed. The ASST was done at baseline, week 9 and week 21. Serum samples (baseline, weeks 9, 13 and/or 21) were analysed for the levels of IgE-anti-IL-24 and immunoglobulin G (IgG)-anti-IL-24 via ELISA and their ability to release histamine in basophils [basophil histamine release assay (BHRA)]. RESULTS: Autologous serum therapy resulted in a substantial improvement in disease activity and quality of life after 8 and 20 weeks. Twenty-eight percent and 34% of patients turned ASST-negative in weeks 9 and 21, respectively, but there was no link between their response to treatment and changes of ASST results. Also, no significant or relevant changes in BHRA were observed. In contrast, autologous serum therapy significantly decreased IgE-anti-IL-24 serum levels, but not IgG-anti-IL-24 serum levels, in responders but not in non-responders. CONCLUSIONS: Our findings suggest that the immunological effects of autologous serum therapy include a reduction in IgE-anti-IL24 autoantibodies, which may contribute to the pathogenesis of CSU.

[Angioedema prophylaxis]. / Prophylaxe von Angioödemen.

Angioedema is a spontaneous, edematous swelling of the deep layers of the skin or mucous membrane. Angioedema in the respiratory tract is potentially life-threatening. The classification of angioedema into mast-cell-mediated (e. g. urticaria) or bradykinin-mediated (e. g. hereditary angioedema) is important for correct and rational treatment. Generally, two therapeutic strategies are available for angioedema treatment. On-demand treatment of angioedema symptoms that already have emerged aims to stop the further development of the attack and, thus, limits the severity and duration of the attack. This strategy is well established in the treatment of patients with hereditary angioedema, whereas in chronic spontaneous urticaria on-demand therapy plays no role in the guideline recommendations. In contrast, the therapeutic strategy of prophylaxis aims to prevent the occurrence of spontaneous and induced attacks as far as possible. Prophylaxis is the sole therapy strategy for chronic urticaria and is applied at all stages of the treatment algorithm. In the case of hereditary angioedema, on-demand therapy can be complemented by prophylaxis after careful and individual indication. In hereditary angioedema, prophylaxis is currently gaining in importance due to improved treatment options. Patients who use a prophylactic regime are much less likely to be forced to wait for the unpredictable occurrence of an attack and then to react with an on-demand treatment. Prophylactic treatment takes place at times determined by the patient himself, in contrast to treatment on an as-needed basis. The loss of unpredictability is a decisive moment in improving the quality of life.

Management of patients with hereditary angioedema in Germany: comparison with other countries in the Icatibant Outcome Survey.

BACKGROUND: The Icatibant Outcome Survey (IOS; NCT01034969) is a Shire-sponsored, international, observational study monitoring the safety and effectiveness of icatibant, a bradykinin B2 receptor antagonist approved for the acute treatment of adults with hereditary angioedema with C1 inhibitor deficiency (HAE-C1-INH). OBJECTIVE: To report IOS data comparing demographic and icatibant treatment outcomes in patients with HAE-C1-INH from Germany to HAE-C1-INH patients from 11 other IOS countries. METHODS: A descriptive, retrospective, comparative analysis of data from 685 IOS patients with HAE-C1-INH from seven centres in Germany (n = 93) vs. centres from Austria, Brazil, Czech Republic, Denmark, France, Greece, Israel, Italy, Spain, Sweden and the United Kingdom (n = 592, July 2009-January 2017). Icatibant treatment outcomes were retrieved from patients with complete attack outcome data for time to treatment, time to resolution and attack duration (160 attacks in 42 German patients and 1442 attacks in 251 patients from other IOS countries). RESULTS: German patients reported significantly fewer severe/very severe attacks (38.7% vs. 57.5%, respectively; P < 0.001). The proportion of attacks treated with a single icatibant injection was significantly higher in German patients (97.1% vs. 91.6%, P = 0.0003). The median time to treatment (0.0 h vs. 1.5 h), time to resolution (3.0 h vs. 7.0 h) and attack duration (4.3 h vs. 10.5 h) in German patients vs. other IOS countries were all significantly shorter (all P < 0.0001). No meaningful differences were identified between patients from Germany and other countries with regard to sex, median age at enrolment, median age at symptom onset and median age at diagnosis. CONCLUSION: German IOS patients share similar demographic characteristics to patients from other IOS countries yet treat their attacks with icatibant significantly earlier and have markedly fewer severe or very severe attacks. Factors including regional access to and availability of icatibant may drive these outcomes and warrant further investigation.

Evaluation of avoralstat, an oral kallikrein inhibitor, in a Phase 3 hereditary angioedema prophylaxis trial: The OPuS-2 study.

BACKGROUND: Effective inhibition of plasma kallikrein may have significant benefits for patients with hereditary angioedema due to deficiency of C1 inhibitor (C1-INH-HAE) by reducing the frequency of angioedema attacks. Avoralstat is a small molecule inhibitor of plasma kallikrein. This study (OPuS-2) evaluated the efficacy and safety of prophylactic avoralstat 300 or 500 mg compared with placebo. METHODS: OPuS-2 was a Phase 3, multicenter, randomized, double-blind, placebo-controlled, parallel-group study. Subjects were administered avoralstat 300 mg, avoralstat 500 mg, or placebo orally 3 times per day for 12 weeks. The primary efficacy endpoint was the angioedema attack rate based on adjudicator-confirmed attacks. RESULTS: A total of 110 subjects were randomized and dosed. The least squares (LS) mean attack rates per week were 0.589, 0.675, and 0.593 for subjects receiving avoralstat 500 mg, avoralstat 300 mg, and placebo, respectively. Overall, 1 subject in each of the avoralstat groups and no subjects in the placebo group were attack-free during the 84-day treatment period. The LS mean duration of all confirmed attacks was 25.4, 29.4, and 31.4 hours for the avoralstat 500 mg, avoralstat 300 mg, and placebo groups, respectively. Using the Angioedema Quality of Life Questionnaire (AE-QoL), improved QoL was observed for the avoralstat 500 mg group compared with placebo. Avoralstat was generally safe and well tolerated. CONCLUSIONS: Although this study did not demonstrate efficacy of avoralstat in preventing angioedema attacks in C1-INH-HAE, it provided evidence of shortened angioedema episodes and improved QoL in the avoralstat 500 mg treatment group compared with placebo.

The international WAO/EAACI guideline for the management of hereditary angioedema-The 2017 revision and update.

Hereditary Angioedema (HAE) is a rare and disabling disease. Early diagnosis and appropriate therapy are essential. This update and revision of the global guideline for HAE provides up-to-date consensus recommendations for the management of HAE. In the development of this update and revision of the guideline, an international expert panel reviewed the existing evidence and developed 20 recommendations that were discussed, finalized and consented during the guideline consensus conference in June 2016 in Vienna. The final version of this update and revision of the guideline incorporates the contributions of a board of expert reviewers and the endorsing societies. The goal of this guideline update and revision is to provide clinicians and their patients with guidance that will assist them in making rational decisions in the management of HAE with deficient C1-inhibitor (type 1) and HAE with dysfunctional C1-inhibitor (type 2). The key clinical questions covered by these recommendations are: (1) How should HAE-1/2 be defined and classified?, (2) How should HAE-1/2 be diagnosed?, (3) Should HAE-1/2 patients receive prophylactic and/or on-demand treatment and what treatment options should be used?, (4) Should HAE-1/2 management be different for special HAE-1/2 patient groups such as pregnant/lactating women or children?, and (5) Should HAE-1/2 management incorporate self-administration of therapies and patient support measures?

The EAACI/GA²LEN/EDF/WAO guideline for the definition, classification, diagnosis and management of urticaria.

This evidence- and consensus-based guideline was developed following the methods recommended by Cochrane and the Grading of Recommendations Assessment, Development and Evaluation (GRADE) working group. The conference was held on 1 December 2016. It is a joint initiative of the Dermatology Section of the European Academy of Allergology and Clinical Immunology (EAACI), the EU-founded network of excellence, the Global Allergy and Asthma European Network (GA²LEN), the European Dermatology Forum (EDF) and the World Allergy Organization (WAO) with the participation of 48 delegates of 42 national and international societies. This guideline was acknowledged and accepted by the European Union of Medical Specialists (UEMS). Urticaria is a frequent, mast cell-driven disease, presenting with wheals, angioedema, or both. The lifetime prevalence for acute urticaria is approximately 20%. Chronic spontaneous urticaria and other chronic forms of urticaria are disabling, impair quality of life and affect performance at work and school. This guideline covers the definition and classification of urticaria, taking into account the recent progress in identifying its causes, eliciting factors and pathomechanisms. In addition, it outlines evidence-based diagnostic and therapeutic approaches for the different subtypes of urticaria.

Histamine intolerance in patients with chronic spontaneous urticaria.

BACKGROUND: Histamine intolerance and pseudoallergy to foods have been suggested to be causes of chronic spontaneous urticaria (CSU) with some patients reporting exacerbation with histamine-rich foods. OBJECTIVE: The study aim was to identify the rate of histamine-intolerant CSU patients and to characterize the relevance of histamine intolerance as an underlying cause of CSU. METHODS: A cohort of 157 of moderate to severe CSU patients (UAS7 ≥ 10) was asked to provide a detailed clinical history, particularly in relation to symptom development after eating histamine-rich foods. They subsequently undertook a histamine-free pseudoallergen-low diet followed by a double-blind, placebo-controlled oral histamine provocation (75 mg). RESULTS: One third of patients (34%) had a positive history of histamine intolerance. There was no statistical difference between the mean UAS7 scores of patients with positive and negative histories (22.4 ± 1.0 vs. 22.7 ± 0.8). When kept on diet, 46% of patients responded with reduced CSU activity (UAS7 reduction of ≥7). Following double-blind, placebo-controlled oral histamine provocation, 17% of patients gave a positive weal response. There appeared to be little relationship between patient history, response to diet and the weal response to oral histamine provocation. First, the history-positive and -negative groups contained similar proportions of diet and histamine provocation weal-positive patients. Second, the diet-positive and -negative groups contained similar proportions of history-positive and histamine provocation weal-positive patients. Third, the histamine provocation weal-positive and -negative groups had similar rates of history- and diet-positive patients. Finally, only 2 of the 157 patients were positive in all three domains. CONCLUSIONS: CSU due to histamine intolerance appears to be rare and cannot be diagnosed based on the history. The study confirms that avoidance diets low in pseudoallergens can improve urticaria symptoms, this is probably not due to the absence of dietary histamine.

The Angioedema Quality of Life Questionnaire (AE-QoL) - assessment of sensitivity to change and minimal clinically important difference.

BACKGROUND: The Angioedema Quality of Life Questionnaire (AE-QoL) has recently been developed and validated as the first specific patient-reported outcome tool to assess quality of life (QoL) impairment in recurrent angioedema patients. As of yet, its sensitivity to change and minimal clinically important difference (MCID) have not been established. METHODS: Recurrent angioedema patients with chronic spontaneous urticaria or hereditary angioedema were repeatedly asked to complete the AE-QoL along with the SF-12 and other anchors for QoL impairment and disease activity during routine care visits. The sensitivity to change of AE-QoL was determined by correlating changes in its scores over time with changes in the applied anchors. In addition, the MCID was determined using anchor-based and distributional criterion-based approaches. RESULTS: Two hundred and seventy-eight patients contributed data sets for analysis. Baseline AE-QoL values were found to correlate well with SF-12 results as well as all other applied anchors for angioedema-related QoL impairment and disease activity. In addition, AE-QoL score changes over time correlated significantly with changes in the above anchors, thus demonstrating its sensitivity to change. The MCID of the AE-QoL total score was found to be six points. CONCLUSION: The AE-QoL is a valuable tool to assess changes of QoL impairment in recurrent angioedema patients over time, including changes due to treatment.

Definition, aims, and implementation of GA(2) LEN Urticaria Centers of Reference and Excellence.

BACKGROUND: GA²LEN, the Global Allergy and Asthma European Network, has recently launched a program for the development, interaction, and accreditation of centers of reference and excellence in special areas of allergy embedded in its overall quality management of allergy centers of excellence. The first area chosen is urticaria. Urticaria is a common and debilitating condition and can be a challenge for both patients and treating physicians, especially when chronic. Centers of reference and excellence in urticaria (UCAREs) can help to improve the management of hard-to-treat conditions such as urticaria. AIMS: Here, we describe the aims, the requirements and deliverables, the application process, and the audit and accreditation protocol for GA²LEN UCAREs. RESULTS: The main aims of GA²LEN UCAREs are to provide excellence in urticaria management, to increase the knowledge of urticaria by research and education, and to promote the awareness of urticaria by advocacy activities. To become a certified GA²LEN UCARE, urticaria centers have to apply and fulfill 32 requirements, defined by specific deliverables that are assessed during an audit visit. DISCUSSION AND CONCLUSION: The GA²LEN UCARE program will result in a strong network of urticaria specialists, promote urticaria research, and harmonize and improve urticaria management globally.

The definition, diagnostic testing, and management of chronic inducible urticarias - The EAACI/GA(2) LEN/EDF/UNEV consensus recommendations 2016 update and revision.

These recommendations for the definition, diagnosis and management of chronic inducible urticaria (CIndU) extend, revise and update our previous consensus report on physical urticarias and cholinergic urticaria (Allergy, 2009). The aim of these recommendations is to improve the diagnosis and management of patients with CIndU. Our recommendations acknowledge the latest changes in our understanding of CIndU, and the available therapeutic options, as well as the development of novel diagnostic tools.

An analysis of the teaching of intravenous self-administration in patients with hereditary angio-oedema.

BACKGROUND: Hereditary angio-oedema (HAE), C1 inhibitor HAE (C1-INH-HAE) type I and C1-INH-HAE type II, are inherited disorders characterised by potentially life-threatening recurrent swellings, caused by a deficiency of C1 inhibitor. Management includes attack treatment or prevention using prophylaxis/routine prevention. AIM: To evaluate the success of self-administration training as part of a home care programme for treatment of HAE using intravenous C1 inhibitor. METHODS: In total, 18 patients (7 men, 11 women; aged 18-72 years) were trained to self-administer a plasma-derived C1 inhibitor concentrate for acute treatment or routine prevention of HAE attacks. The number of training sessions needed to learn intravenous self-administration, delay in time to treatment and reduction in attack frequency (per month) were evaluated after completion of the training. RESULTS: All patients successfully completed training. The median number of training sessions required to be capable of unassisted/independent self-injection was 5 (range 2-30). Time to treatment was reduced from a median of 4.5 h (270 min) by medical professionals to 15 min by patients after self-administration training). Using the treatment as routine prevention resulted in a reduction of median frequency of attacks from 8 to 0.5 attacks/month. CONCLUSION: C1 inhibitor self-administration for the treatment of HAE allows patients to quickly treat attacks at home, potentially reducing attack severity. The results also demonstrate the benefit of self-administered routine prevention therapy in a real-world patient population. Self-administered therapy potentially allows patients to gain greater control over their attacks, resulting in a reduction in healthcare utilization.

Subcutaneous self-injections of C1 inhibitor: an effective and safe treatment in a patient with hereditary angio-oedema.

A 25-year-old woman presented to our clinic with a history of recurrent swelling and abdominal symptoms for > 20 years. The patient's father was similarly affected. The patient was diagnosed with hereditary angio-oedema (HAE) due to C1 inhibitor deficiency. This was initially managed with systemic androgens, but the symptoms of hyperandrogenism eventually became intolerable. Treatment with icatibant (an antagonist of bradykinin B2 receptors) was partially successful. We changed the therapy to prophylactic treatment with C1 inhibitor. Although the patient became completely symptom-free under this regimen, she found the repeated intravenous injections unacceptable. Therefore, we changed the route of administration to subcutaneous injections of C1 inhibitor 1000 U in 10 mL twice weekly, using a subcutaneous infusion kit. Since that time (December 2013), she has remained completely free of symptoms under this regimen. To our knowledge, this is the first report documenting the efficacy and safety of subcutaneous injections of C1 inhibitor in a patient with HAE.

F12-46C/T polymorphism as modifier of the clinical phenotype of hereditary angioedema.

The factors influencing the heterogeneous clinical manifestation of hereditary angioedema due to C1-INH deficiency (C1-INH-HAE) represent one of the oldest unsolved problems of the disease. Considering that factor XII (FXII) levels may affect bradykinin production, we investigated the contribution of the functional promoter polymorphism F12-46C/T in disease phenotype. We studied 258 C1-INH-HAE patients from 113 European families, and we explored possible associations of F12-46C/T with clinical features and the SERPING1 mutational status. Given that our cohort consisted of related subjects, we implemented generalized estimating equations (GEEs), an extension of the generalized linear model accounting for the within-subject correlation. F12-46C/T carriers exhibited a significantly delayed disease onset (P < 0.001) and did not need long-term treatment (P = 0.02). In a GEE linear regression model, the presence of F12-46C/T was significantly associated with a 7-year delay in disease onset (P < 0.0001) regardless of SERPING1 mutational status. It is concluded that F12-46C/T carriage acts as an independent modifier of C1-INH-HAE severity.

Phase II study results of a replacement therapy for hereditary angioedema with subcutaneous C1-inhibitor concentrate.

BACKGROUND: Hereditary angioedema (HAE) due to C1 inhibitor deficiency manifests as recurrent swelling attacks that can be disabling and sometimes fatal. Long-term prophylaxis with twice-weekly intravenous injections of plasma-derived C1-inhibitor (pdC1-INH) has been established as an effective treatment. Subcutaneous (SC) administration of pdC1-INH has not been studied in patients with HAE. METHODS: This open-label, dose-ranging, crossover study (COMPACT Phase II) was conducted in 18 patients with type I or II HAE who received two of twice-weekly 1500, 3000, or 6000 IU SC doses of highly concentrated volume-reduced CSL830 for 4 weeks each. The mean trough plasma levels of C1-INH functional activity, C1-INH and C4 antigen levels during Week 4, and overall safety and tolerability were evaluated. The primary outcome was model-derived steady-state trough C1-INH functional activity. RESULTS: After SC CSL830 administration, a dose-dependent increase in trough functional C1-INH activity was observed. C1-INH and C4 levels both increased. The two highest dose groups (3000 and 6000 IU) achieved constant C1-INH activity levels above 40% values, a threshold that was assumed to provide clinical protection against angioedema attacks. Compared with intravenous injection, pdC1-INH SC injection with CSL830 showed a lower peak-to-trough ratio and more consistent exposures. All doses were well tolerated. Mild-to-moderate local site reactions were noted with pain and swelling being the most common adverse event. CONCLUSIONS: Subcutaneous volume-reduced CSL830 was well tolerated and led to a dose-dependent increase in physiologically relevant functional C1-INH plasma levels. A clinical outcome study of SC CSL830 in patients with HAE warrants further investigation.

An improved Peltier effect-based instrument for critical temperature threshold measurement in cold- and heat-induced urticaria.

BACKGROUND: Cold- and heat-induced urticaria are chronic physical urticaria conditions in which wheals, angioedema or both are evoked by skin exposure to cold and heat respectively. The diagnostic work up of both conditions should include skin provocation tests and accurate determination of critical temperature thresholds (CTT) for producing symptoms in order to be able to predict the potential risk that each individual patient faces and how this may be ameliorated by therapy. OBJECTIVE: To develop and validate TempTest(®) 4, a simple and relatively inexpensive instrument for the accurate determination of CTT which may be used in clinical practice. METHODS: TempTest(®) 4 has a single 2 mm wide 350 mm U-shaped Peltier element generating a temperature gradient from 4 °C to 44 °C along its length. Using a clear plastic guide placed over the skin after provocation, CTT values may be determined with an accuracy of ±1 °C. Here, TempTest(®) 4 was compared with its much more expensive predecessor, TempTest(®) 3, in inducing wheals in 30 cold urticaria patients. RESULTS: Both TempTest(®) 4 and TempTest(®) 3 induced wheals in all 30 patients between 8 ° and 28 °C. There was a highly significant (P < 0.0001) correlation between the instruments in the CTT values in individual patients. CONCLUSION: The TempTest(®) 4 is a simple, easy to use, licensed, commercially available and affordable instrument for the determination of CTTs in both cold- and heat-induced urticaria.