Icatibant averting mechanical ventilation in acute ischemic stroke patient with alteplase-induced orolingual angioedema

BACKGROUND AND PURPOSE

Orolingual angioedema (OA) represents a rare but life-threatening complication among patients with acute ischemic stroke treated with intravenous thrombolysis with alteplase. Novel agents, including icatibant, are recommended in resistant patients with alteplase-induced OA who have failed to respond to first-line therapies including corticosteroids, antihistamines, and/or adrenaline.

METHODS

We present a patient with alteplase-induced OA who showed substantial clinical improvement following the administration of icatibant.

RESULTS

We describe a 71-year-old woman with known arterial hypertension under treatment with angiotensin-converting enzyme inhibitor, who presented with acute ischemic stroke in the territory of the right middle cerebral artery and received intravenous alteplase. During intravenous thrombolysis, the case was complicated with OA without any response to standard anaphylactic treatment including corticosteroids, dimetindene, and adrenaline. Thirty minutes after symptom onset, icatibant, a synthetic selective bradykinin B2-receptor antagonist, was administered subcutaneously. Substantial symptomatic resolution was observed only following the icatibant administration.

CONCLUSIONS

This case highlights the effectiveness of icatibant in the acute management of alteplase-induced OA. In particular, icatibant administration, following first-line therapies including corticosteroids, antihistamines, and/or adrenaline, may avert tracheostomy and intubation in resistant and refractory cases with OA following intravenous thrombolysis for acute ischemic stroke.

Acute angioedema in Cape Town emergency centres and a suggested algorithm to simplify and improve management

BACKGROUND

Angioedema is the most common acute allergic presentation to emergency centres (EC), with hospitalisation rates increasing in high-income countries. Angioedema can complicate with life-threatening laryngeal obstruction. There are no local data; therefore, we aimed to characterise acute angioedema cases presenting to ECs and develop a simple management algorithm.

OBJECTIVE

To characterise the clinical presentation, management and outcomes of acute angioedema cases presenting to ECs. Based on these findings, we developed a management algorithm for acute angioedema to improve the care of acute angioedema in South Africa (SA).

METHODS

We conducted a retrospective folder review of all patients admitted to Groote Schuur Hospital (tertiary) and Mitchells Plain District Hospital (secondary) ECs from 1  June 2018 to 31  June 2020. Using ICD-10 coding, folders of adults ≥18 years with possible angioedema presenting to the ECs were screened. An allergist extracted demographics, medical history, management and outcome data for each angioedema event.

RESULTS

A total of 142 acute angioedema episodes were included, with a median (interquartile range) age of 42 (28 - 58) years, and 62% of patients were female. The majority (124/142, 87%) of acute angioedema EC presentations involved swelling above the shoulders, with airway involvement in 20 (14%) patients, with two patients requiring intubation. Nineteen (13%) patients required admission, with five (26%) admitted to high care/intensive care. Drug-induced angioedema was the most common cause, with 64/142 (45%) linked to a known offending drug, 42/64 (65.6%) being angiotensin-converting enzyme inhibitor (ACE-I). Critical information to guide angioedema management, including past personal/family allergy history, and duration of angioedema prior to EC visit, was not recorded in 64.7% and 37.8% of EC records, respectively. Unnecessary treatment with corticosteroids or antihistamines occurred in 19/53 (36%) and 16/53 (30%) cases with bradykinin-mediated angioedema ACE-I angioedema and hereditary angioedema). Overall, only 36/142 (25%) of angioedema patients were connected to allergy care.

CONCLUSION

Angioedema is the most common allergy presentation to two ECs in Cape Town, SA. Bradykinin-mediated angioedema secondary to ACE-I therapy is the single most common offender, and was not appropriately managed in more than a third of cases. Based on these findings, we have developed a management algorithm that easily stratifies patients into bradykinin or mast cell-mediated angioedema with a step-by-step management approach that is applicable to the SA context. Ongoing awareness and education on allergy emergencies are required to ensure accurate diagnosis of less common causes of angioedema (particularly bradykinin-mediated angioedema) and linkage to allergy specialist care.

A case of acquired angioedema

ABSTRACT

Acquired angioedema is a rare disorder characterized by nonurticarial angioedema secondary to deficiency or altered activity of C1-esterase inhibitor protein. This article describes a patient whose recurrent angioedema was initially diagnosed as angiotensin-converting enzyme (ACE) inhibitor-induced angioedema. However, after further testing, she was diagnosed with acquired angioedema and subsequently treated with a synthetic bradykinin B2-receptor antagonist.

Management of hereditary angioedema in Japan: Focus on icatibant for the treatment of acute attacks

Hereditary angioedema (HAE) is characterized by unpredictable, recurring and painful swelling episodes that can be disabling or even life-threatening. Awareness of HAE has progressively grown worldwide, and options for treatment of acute attacks and prevention of future attacks continue to expand; however, unmet needs in diagnosis and treatment remain. In Japan, recognition of HAE within the medical community remains low, and numerous obstacles complicate diagnosis and access to treatment. Importance of timely treatment of HAE attacks with on-demand therapies is continually demonstrated; recommended agents per the WAO/EAACI treatment guidelines published in 2018 include C1 inhibitor (C1-INH) concentrate, ecallantide, and icatibant. In Japan, multiple factors contribute to delayed HAE treatment (potentially leading to life-threatening consequences), including difficulties in finding facilities at which C1-INH agents are readily available. Recognition of challenges faced in Japan can help promote efforts to address current needs and expand access to effective therapies. Icatibant, a potent, selective bradykinin B₂ receptor antagonist, has demonstrated inhibition of various bradykinin-induced biological effects in preclinical studies and has shown efficacy in treating attacks in various clinical settings (e.g. clinical trials, real-world studies), and HAE patient populations (e.g. with C1-INH deficiency, normal C1-INH). Icatibant was approved in Japan for the treatment of HAE attacks in September 2018; its addition to the HAE treatment armamentarium contributes to improved patient care. In Japan, disease awareness and education campaigns are warranted to further advance the management of HAE patients in light of the unmet needs and the emerging availability of modern diagnostic approaches and therapies.

[Update on perioperative hypersensitivity reactions: joint document from the Brazilian Society of Anesthesiology (SBA) and Brazilian Association of Allergy and Immunology (ASBAI) - Part II: etiology and diagnosis]

This second joint document, written by experts from the Brazilian Association of Allergy and Immunology (ASBAI) and Brazilian Society of Anesthesiology (SBA) concerned with perioperative anaphylaxis, aims to review the pathophysiological reaction mechanisms, triggering agents (in adults and children), and the approach for diagnosis during and after an episode of anaphylaxis. As anaphylaxis assessment is extensive, the identification of medications, antiseptics and other substances used at each setting, the comprehensive data documentation, and the use of standardized nomenclature are key points for obtaining more consistent epidemiological information on perioperative anaphylaxis.

Icatibant Outcome Survey in Patients with Hereditary Angioedema: Experience in Israel Compared with Other Countries

BACKGROUND

Management of patients with hereditary angioedema with C1-inhibitor deficiency (C1-INH-HAE) is evolving worldwide. Evaluating the Israeli experience may provide valuable insights.

OBJECTIVES

To compare demographics and icatibant treatment patterns and outcomes in patients with C1-INH-HAE enrolled in the Icatibant Outcome Survey (IOS) in Israel with those in other countries.

METHODS

The IOS is an ongoing observational study that prospectively monitors real-world icatibant safety/tolerability and treatment outcomes.

RESULTS

By July 2016, 58 patients from Israel and 594 patients from other countries were enrolled. Median age at diagnosis (16.7 vs. 21.3 years, P = 0.036) and median delay between symptom onset and diagnosis (0.8 vs. 6.6 years, P = 0.025) were lower in Israel compared with other countries, respectively. Differences in attack severity were not significant (P = 0.156); however, during follow-up, Israeli patients were less likely to miss > 7 days of work/school due to C1-INH-HAE-related complications (P = 0.007). A trend was also shown in Israel for earlier time to treatment (median 0.5 vs. 1.3 hours, P = 0.076), attack duration was shorter (median 5.0 vs. 9.0 hours, P = 0.026), and patients more often self-administered icatibant (97.2% vs. 87.5%, P = 0.003), respectively. However, Israeli patients were less likely to treat attacks (P = 0.036). Whereas patients in Israel reported exclusive use of danazol for long-term prophylaxis, those in other countries used various agents, including C1-INH.

CONCLUSIONS

Recognition of C1-INH-HAE and timeliness of icatibant treatment appear more favorable, and attack duration shorter, in Israel compared with other countries.

[EFFICACY, PHARMACOKINETICS, AND SAFETY OF ICATIBANT FOR THE TREATMENT OF JAPANESE PATIENTS WITH AN ACUTE ATTACK OF HEREDITARY ANGIOEDEMA: A PHASE 3 OPEN-LABEL STUDY]

BACKGROUND

Hereditary angioedema (HAE) is characterized by paroxysmal edema of the skin, gastrointestinal mucosa, and upper respiratory tract.

PURPOSE

This study investigated icatibant, a selective bradykinin B2 receptor antagonist, as treatment for Japanese patients with an acute HAE attack.

METHODS

This was an open-label, single-arm, Phase 3 study of Japanese adults with HAE type I or II. Icatibant (30 mg) was administered (by a healthcare professional [HCP] or self-administered) as a subcutaneous injection in the abdomen.

RESULTS

Eight patients (4 cutaneous, 3 abdominal, 1 laryngeal) were treated with icatibant (all single injection; 3 self-administered, 5 HCP-administered). The median time to onset of symptom relief was 1.75 hours (95% confidence interval, 1.00 to 2.50); all patients had onset of relief within 5 hours. The estimated time to maximum icatibant concentration in the circulation was 1.79 hours and the maximum concentration was 405 ng/mL. There were 3 patients who experienced 3 adverse events (2 HAE attacks and 1 headache); 7 patients experienced an injection site reaction.

CONCLUSION

Although our study was limited by the small number of patients, we found that icatibant was an effective and well-tolerated treatment for Japanese patients with acute HAE attacks, regardless of whether it was administered by a HCP or self-administered.

Evaluating satisfaction of patients with hereditary angioedema with their past and present treatments: Implications for future therapies

BACKGROUND

Ever-expanding armamentarium of treatments for hereditary angioedema (HAE) are associated with various adverse effects, issues with vascular access, or lack of self-administration.

OBJECTIVE

To understand patients' impressions and confidence in their past and present treatments, and identifying adverse events while also directly asking patients to reveal their hope for the future of HAE management and treatments.

METHODS

After institutional review board approval, all subjects with laboratory-confirmed HAE were mailed a survey that they completed and returned to the researchers, and data were collected and entered into a secure online web application for surveys. Medication confidence data were summarized and expressed as means, medians, standard deviations, and quartiles by using a 5-point Likert scale. Analyses were performed by using statistical software.

RESULTS

Of 150 surveys, 38 (25.3%) were completed. Among 36 subjects, 27 (75.0%) were female subjects, and the mean age was 50.1 years. Cinryze and Berinert (both C1-esterase inhibitors) had the highest median scores (5.0) for patient confidence, followed by ecallantide (4.5), icatibant (4.0), and androgens (2.0). For Cinryze, 64.3% selected it as the most effective and 57.1% tolerated it best. For Berinert, 50% of the subjects found it to be most effective and 59.1% tolerated it best. Some subjects listed androgens as most effective (33.3%) or best tolerated (16.7%), and many reported that this class caused the most adverse effects (44.4%). Among those who answered, 50% preferred a noninvasive method of administration, such as oral (24%), subcutaneous (18%), or not intravenous (8%) routes.

CONCLUSION

Determining patient predilections and the reasoning behind them can be valuable for determining specific therapies to achieve each individual's personal goals.

A randomized trial of icatibant in ACE-inhibitor-induced angioedema

BACKGROUND

Angioedema induced by treatment with angiotensin-converting-enzyme (ACE) inhibitors accounts for one third of angioedema cases in the emergency room; it is usually manifested in the upper airway and the head and neck region. There is no approved treatment for this potentially life-threatening condition.

METHODS

In this multicenter, double-blind, double-dummy, randomized phase 2 study, we assigned patients who had ACE-inhibitor-induced angioedema of the upper aerodigestive tract to treatment with 30 mg of subcutaneous icatibant, a selective bradykinin B2 receptor antagonist, or to the current off-label standard therapy consisting of intravenous prednisolone (500 mg) plus clemastine (2 mg). The primary efficacy end point was the median time to complete resolution of edema.

RESULTS

All 27 patients in the per-protocol population had complete resolution of edema. The median time to complete resolution was 8.0 hours (interquartile range, 3.0 to 16.0) with icatibant as compared with 27.1 hours (interquartile range, 20.3 to 48.0) with standard therapy (P=0.002). Three patients receiving standard therapy required rescue intervention with icatibant and prednisolone; 1 patient required tracheotomy. Significantly more patients in the icatibant group than in the standard-therapy group had complete resolution of edema within 4 hours after treatment (5 of 13 vs. 0 of 14, P=0.02). The median time to the onset of symptom relief (according to a composite investigator-assessed symptom score) was significantly shorter with icatibant than with standard therapy (2.0 hours vs. 11.7 hours, P=0.03). The results were similar when patient-assessed symptom scores were used.

CONCLUSIONS

Among patients with ACE-inhibitor-induced angioedema, the time to complete resolution of edema was significantly shorter with icatibant than with combination therapy with a glucocorticoid and an antihistamine. (Funded by Shire and the Federal Ministry of Education and Research of Germany; ClinicalTrials.gov number, NCT01154361.).

[Drug induced angioedema (ACE-inhibitors and other)]

Angiotensin Converting Enzyme inhibitors (ACE-I) use is a frequent cause of AE and must be suspected systematically in all patients with AE. The risk of AE is increased in: black people, transplanted patients, those who take gliptins or immunosuppressants (mTOR i). Angiotensin converting enzyme inhibitors induced angioedema (ACE-I AE) can occur a few days to several years after the beginning of this treatment and persist a few months after stopping it. ACE-I AE affect mainly the face and particularly the tongue but also the abdomen. ACE-I AE can be life threatening, due to the involvement of the tongue and the larynx. ACE-I AE must be treated as in the hereditary form when life threatening signs are present, with icatibant or C1 inhibitor concentrate. AE can occur in 10% of angiotensin receptor blockers (ARBs) treated patients who had developed ACE-I AE.

[Emergency management of bradykinin-mediated angioedema]

In the emergency setting, the diagnosis of bradykinin-mediated angioedema is based exclusively on history and physical examination. Severe attacks must be identified because the evolution is unpredictable with a risk of life-threatening airway obstruction. Underestimate the severity of the attack is a management pitfall to avoid. All attack under the shoulders should be considered as severe and must benefit from early specific treatment.

Icatibant, an inhibitor of bradykinin receptor 2, for hereditary angioedema attacks: prospective experimental single-cohort study

CONTEXT AND OBJECTIVE

Hereditary angioedema (HAE) with C1 inhibitor deficiency manifests as recurrent episodes of edema involving the skin, upper respiratory tract and gastrointestinal tract. It can be lethal due to asphyxia. The aim here was to evaluate the response to therapy for these attacks using icatibant, an inhibitor of the bradykinin receptor, which was recently introduced into Brazil.

DESIGN AND SETTING

Prospective experimental single-cohort study on the efficacy and safety of icatibant for HAE patients.

METHODS

Patients with a confirmed HAE diagnosis were enrolled according to symptoms and regardless of the time since onset of the attack. Icatibant was administered in accordance with the protocol that has been approved in Brazil. Symptom severity was assessed continuously and adverse events were monitored.

RESULTS

24 attacks in 20 HAE patients were treated (female/male 19:1; 19-55 years; median 29 years of age). The symptoms were: subcutaneous edema (22/24); abdominal pain (15/24) and upper airway obstruction (10/24). The time taken until onset of relief was: 5-10 minutes (5/24; 20.8%); 10-20 (5/24; 20.8%); 20-30 (8/24; 33.4%); 30-60 (5/24; 20.8%); and 2 hours (1/24; 4.3%). The time taken for complete resolution of symptoms ranged from 4.3 to 33.4 hours. Adverse effects were only reported at injection sites. Mild to moderate erythema and/or feelings of burning were reported by 15/24 patients, itching by 3 and no adverse effects in 6.

CONCLUSION

HAE type I patients who received icatibant responded promptly; most achieved improved symptom severity within 30 minutes. Local adverse events occurred in 75% of the patients.

Preclinical pharmacology, metabolic stability, pharmacokinetics and toxicology of the peptidic kinin B1 receptor antagonist R-954

We previously showed that R-954 (AcOrn[Oic(2),(αMe)Phe(5),dβNal(7),Ile(8)]desArg(9)-bradykinin) is a potent, selective and stable peptide antagonist of the inducible GPCR kinin B1 receptor. This compound shows potential applications for the treatment of several diseases, including cancer and neurological disturbances of diabetes. To enable clinical translation, more information regarding its pharmacological, pharmacokinetics (PK) and toxicological properties at preclinical stage is warranted. This was the principal objective of the present study. Herein, specificity of R-954 was characterized in binding studies on 133 human molecular targets to reveal minor cross-reactivities against the angiotensin AT2 and the bombesin receptors (110- and 330-fold lower affinity than for B1R, respectively). The pharmacokinetic of R-954 was studied in both normal and streptozotocin-diabetic anaesthetized rats providing half-lives of 1.9-2.7h. R-954 does not appear to be metabolized in the rat circulation and in several rat tissue homogenates, as the kidney, lung and liver. It appears to be excreted as parent drug in the bile (21%) and in urine. A preliminary toxicological profile of R-954 was obtained in rats under various administration routes. R-954 appears to be well tolerated. Overall, these results indicate that R-954 exhibits favorable preclinical pharmacological/PK characteristics and encouraging safety profiles, suitable for early studies in humans.

Lump in the throat - a case study

Jack, aged 66 years, presented to his general practitioner with a foreign body sensation in his throat and altered voice, which developed over 30 minutes. He was otherwise well, having no other new symptoms or recent alterations to medication. He had not eaten anything unusual. He had hypertension, type 2 diabetes, stable ischaemic heart disease, urolithiasis and benign prostatic hypertrophy. His regular medication was metformin, rosuvastatin, carvedilol, candesartan (last 5 years) and saxagliptin (last 6 months). He had no allergies but was intolerant of ramipril due to cough. There was no family history of note. On examination he had no itch or rash, or swelling of the tongue, lips, cheek or neck. However, there was oedema of the soft palate and uvula. He was maintaining his airway, saturating at 98%, and his chest was clear. He was afebrile and systemically well.

Hereditary angioedema therapies in the United States: movement toward an international treatment consensus

BACKGROUND

Hereditary angioedema (HAE) is a rare, potentially life-threatening autosomal dominant disease characterized by recurrent angioedema attacks that affect the skin, gastrointestinal tract, and airway, including the larynx. Pharmacologic developments in HAE treatment have culminated in the recent introduction of 4 new HAE-specific therapies in the United States.

OBJECTIVES

In light of these new therapeutic options, this commentary outlines historical US HAE therapy choices, discusses the potential effect of the 4 recently approved HAE treatments, and considers strategies for optimizing their use in line with international treatment recommendations.

DISCUSSION

Treatment options for HAE in the United States have been limited to attenuated androgens and antifibrinolytic agents for long-term prophylaxis and FFP and supportive therapy for the management of acute attacks. The 4 new therapies that have recently become available (ie, 2 plasma-derived C1 esterase inhibitor (C1-INH) concentrates, the kallikrein inhibitor ecallantide, and the bradykinin β(2)-antagonist icatibant) have provided an opportunity to change routine HAE treatment. In 2009, despite the availability of 2 of the new treatments (ie, the plasma-derived C1-INH concentrates), a large survey of US physicians suggested that wide variability still existed in the treatment of patients with HAE. Since this survey was undertaken, clinical experience with all 4 new treatments has increased significantly, and because 3 of these agents (ie, 2 plasma-derived C1-INH concentrates and icatibant) can be self-administered by trained patients, physicians can now provide individualized care that is proven effective and more aligned with international guidance.

Evidence-based recommendations for the therapeutic management of angioedema owing to hereditary C1 inhibitor deficiency: consensus report of an International Working Group

Angioedema owing to hereditary deficiency of C1 inhibitor (HAE) is a rare, life-threatening, disabling disease. In the last 2 years, the results of well-designed and controlled trials with existing and new therapies for this condition have been published, and new treatments reached the market. Current guidelines for the treatment for HAE were released before the new trials and before the new treatments became available and were essentially based on observational studies and expert opinion. To provide evidence-based HAE treatment guidelines supported by the new studies, a conference was held in Gargnano del Garda, Italy, from September 26 to 29, 2010. The meeting hosted 58 experienced HAE expert physicians, representatives of pharmaceutical companies and representatives of HAE patients' associations. Here, we report the topics discussed during the meeting and evidence-based consensus about management approaches for HAE in adult/adolescent patients.

Consensus statement on the diagnosis, management, and treatment of angioedema mediated by bradykinin. Part I. Classification, epidemiology, pathophysiology, genetics, clinical symptoms, and diagnosis

BACKGROUND

There are no Spanish guidelines or consensus statement on bradykinin-induced angioedema.

AIM

To review the pathophysiology, genetics, and clinical symptoms of the different types of bradykinin-induced angioedema and to draft a consensus statement in light of currently available scientific evidence and the experience of experts. This statement will serve as a guideline to health professionals.

METHODS

The consensus was led by the Spanish Study Group on Bradykinin-Induced Angioedema (SGBA), a working group of the Spanish Society of Allergology and Clinical Immunology. A review was conducted of scientific papers on different types of bradykinin-induced angioedema (hereditary and acquired angioedema due to C1 inhibitor deficiency, hereditary angioedema related to estrogens, angioedema induced by angiotensin-converting enzyme inhibitors). Several discussion meetings of the SGBA were held in Madrid to reach the consensus.

RESULTS

The pathophysiology, genetics, and clinical symptoms of the different types of angioedema are reviewed. Diagnostic approaches are discussed and the consensus reached is described.

CONCLUSIONS

A review of bradykinin-induced angioedema and a consensus on diagnosis are presented.

Icatibant. Attacks of hereditary angioedema: continue to use C1 esterase inhibitor

Hereditary angioedema is a severe genetic disorder due to C1 esterase inhibitor deficiency, which leads to an excess of bradykinin. It is characterised by attacks of subcutaneous or mucosal oedema, which can carry a risk of asphyxiation if the larynx is involved. The first-choice symptomatic treatment for attacks is intravenous C1 esterase inhibitor administration. Tranexamic acid is sometimes used. Icatibant, a decapeptide bradykinin B2 receptor antagonist, is now authorised in the European Union for use in this situation. We found no trials comparing icatibant versus C1 esterase inhibitor. The two principal clinical trials were both comparative trials, one versus tranexamic acid (74 patients), and the other versus placebo (56 patients). No mortality data were reported in either trial. Icatibant seemed to be more effective than tranexamic acid in relieving symptoms and also yielded a higher response rate. However, these positive results were not confirmed in the placebo-controlled trial. Both trials suffer from several biases, ruling out firm conclusions on the efficacy of icatibant, the trials were underpowered, some criteria were difficult to measure, the blinding was incomplete, and tranexamic acid was given at a lower dose than that recommended. The main adverse effects of icatibant are reactions at the injection site, which occur in almost all patients. A potential risk of cardiac disorders (especially angina) needs to be investigated. Subcutaneous administration of icatibant requires a large volume of solution (3 ml). In practice, in the absence of head-to-head comparisons, it remains to be shown whether or not icatibant has a better risk-benefit balance than C1 esterase inhibitor. Due to inconsistencies between the results and numerous biases in the two main clinical trials, the evidence supporting the efficacy of icatibant is weak. C1 esterase inhibitor remains the first-choice treatment for patients with acute attacks of hereditary angioedema.

Icatibant, a new bradykinin-receptor antagonist, in hereditary angioedema

BACKGROUND

Hereditary angioedema is characterized by recurrent attacks of angioedema of the skin, larynx, and gastrointestinal tract. Bradykinin is the key mediator of symptoms. Icatibant is a selective bradykinin B2 receptor antagonist.

METHODS

In two double-blind, randomized, multicenter trials, we evaluated the effect of icatibant in patients with hereditary angioedema presenting with cutaneous or abdominal attacks. In the For Angioedema Subcutaneous Treatment (FAST) 1 trial, patients received either icatibant or placebo; in FAST-2, patients received either icatibant or oral tranexamic acid, at a dose of 3 g daily for 2 days. Icatibant was given once, subcutaneously, at a dose of 30 mg. The primary end point was the median time to clinically significant relief of symptoms.

RESULTS

A total of 56 and 74 patients underwent randomization in the FAST-1 and FAST-2 trials, respectively. The primary end point was reached in 2.5 hours with icatibant versus 4.6 hours with placebo in the FAST-1 trial (P=0.14) and in 2.0 hours with icatibant versus 12.0 hours with tranexamic acid in the FAST-2 trial (P<0.001). In the FAST-1 study, 3 recipients of icatibant and 13 recipients of placebo needed treatment with rescue medication. The median time to first improvement of symptoms, as assessed by patients and by investigators, was significantly shorter with icatibant in both trials. No icatibant-related serious adverse events were reported.

CONCLUSIONS

In patients with hereditary angioedema having acute attacks, we found a significant benefit of icatibant as compared with tranexamic acid in one trial and a nonsignificant benefit of icatibant as compared with placebo in the other trial with regard to the primary end point. The early use of rescue medication may have obscured the benefit of icatibant in the placebo trial. (Funded by Jerini; ClinicalTrials.gov numbers, NCT00097695 and NCT00500656.)

Hereditary angioedema: new hopes for an orphan disease

Hereditary angioedema is a rare genetic disorder, manifested by recurrent edema leading to disfigurement, organ dysfunction and life-threatening respiratory impairment that may become fatal. The hallmark of HAE is C1 esterase inhibitor deficiency, but recent evidence points at bradykinin as the main mediator that causes hyperpermeability of small vasculature, leading to accumulation of edema fluid. Current therapeutic options for HAE are limited, and consist of drugs, replacement therapy, and supportive treatment. In view of many disadvantages of the current therapeutic modalities, new approaches to the treatment of HAE are now being offered. This review summarizes our experience with a new line of medications developed for the treatment of acute exacerbations and prophylaxis of HAE--icatibant: bradykinin receptor antagonist, ecallantide: kallikrein inhibitor, and two C1 INH preparations: Berinert-P, human plasma-derived concentrate, and Rhucin: novel recombinant C1-INH produced in transgenic rabbits. Preliminary results of these studies are encouraging and may bring new hope to the patients with this distressing condition. The exact number of HAE patients in Israel is unknown and because patients are treated individually and comprehensive laboratory assessment is partial, many cases might be missed or not treated according to accepted guidelines. We offer a new specialty center for HAE patients, addressing the medical and psychosocial needs of patients and their families.

Neuronal activation at the spinal cord and medullary pain control centers after joint stimulation: a c-fos study in acute and chronic articular inflammation

Chronic inflammatory pain induces short- and long-term central changes, which have been mainly studied at the spinal cord level. Supraspinal pain control centers intrinsically connected with the dorsal horn are also prone to be affected by chronic inflammatory pain. C-fos expression was used as a neuronal activation marker at spinal and supraspinal levels to i) compare acute and chronic articular inflammation, and ii) analyze the effects of brief innocuous or noxious stimulation of a chronically inflamed joint. Acute articular inflammation was induced by an inflammatory soup with prostaglandin E(2) and bradykinin, both at 10(-5) M. Chronic articular inflammation consisted of 14 days of monoarthritis. Early c-fos expression was studied 4 min after inflammatory soup injection or stimulation of the arthritic joint whereas late c-fos expression was evaluated 2 h after those stimuli. At the spinal cord, the analysis was focused on the dorsal horn (laminae I-V) and supraspinally, five major regions of the endogenous pain control system were considered: the caudal ventrolateral medulla (VLM), the dorsal reticular nucleus (DRt), the ventral reticular nucleus (VRt), the nucleus of the solitary tract (Sol) and the rostroventromedial medulla (RVM). Acute articular inflammation induced early and late increases in c-fos expression at the spinal level and late increases supraspinally whereas the effects of monoarthritis were more moderate and restricted to the spinal cord. When monoarthritic animals were subjected to gentle touch or bending of the joint, early increases in c-fos expression were detected supraspinally, but not at the spinal level. In this region, noxious mechanical stimulation induced late increases in non-inflamed animals and both early and late increases in monoarthritic rats. Supraspinally, noxious stimulation induced only late increases in c-fos expression. The present results show complex differences in the patterns of c-fos expression between the spinal cord and medullary areas of the pain control system during articular inflammation, which indicate that the somatosensory system is differentially affected by the installation of chronic pain.

Gastrocardiac afferent convergence in upper thoracic spinal neurons: a central mechanism of postprandial angina pectoris

The aim of this study was to examine whether gastric afferent information converged onto upper thoracic spinal neurons that received noxious cardiac input. Extracellular potentials of single upper thoracic (T3) spinal neurons were recorded in pentobarbital-anesthetized, paralyzed, ventilated male rats. Gastric distension (GD) (20, 40, 60 mm Hg, 20 seconds) was produced by air inflation of a latex balloon surgically placed in the stomach. A catheter was placed in the pericardial sac to administer bradykinin solution (10 microg/mL, 0.2 mL, 1 minute) as a noxious cardiac stimulus. Noxious GD (> or =40 mm Hg) altered activity of 26 of 31 (84%) spinal neurons receiving cardiac input. Twenty-two (85%) gastrocardiac convergent neurons were excited, and 1 neuron was inhibited by both intrapericardial bradykinin and GD; the remainder exhibited biphasic response patterns. Twenty-three of 26 (88%) gastrocardiac neurons also received convergent somatic input from the chest, triceps, and upper back areas. Bilateral cervical vagotomy did not significantly affect excitatory responses to GD in 5 of 5 neurons tested. Spinal transection at the C1 segment after vagotomy did not affect excitatory responses to GD in 3 of 4 neurons but abolished the GD response in 1 neuron. These data showed that a gastric stimulus excited T3 spinal neurons with noxious cardiac input primarily by way of intraspinal ascending pathways.

PERSPECTIVE

Convergence of gastric afferent input onto upper thoracic spinal neurons receiving noxious cardiac input that was observed in the present study may provide a spinal mechanism that explains stomach-heart cross-organ communication, such as postprandial triggering and worsening of angina pectoris in patients with coronary artery disease.

Bradykinin- and substance P-induced edema formation in the hamster cheek pouch is tyrosine kinase dependent

The purpose of this study was to determine whether protein tyrosine kinase, a ubiquitous family of intracellular signaling enzymes that regulates endothelial cell function, modulates bradykinin- and substance P-induced increase in macromolecular efflux from the intact hamster cheek pouch microcirculation. Using intravital microscopy, I found that suffusion of bradykinin or substance P (each, 0.5 and 1.0 microM) onto the cheek pouch elicited significant, concentration-dependent leaky site formation and increase in clearance of fluorescein isothiocyanate-dextran (FITC-dextran; molecular mass, 70 kDa; P < 0.05). These responses were significantly attenuated by suffusion of genistein (1.0 microM) or tyrphostin 25 (10 microM), two structurally unrelated, nonspecific protein tyrosine kinase inhibitors (P < 0.05). Conceivably, the kinase(s) involved in this process could be agonist specific because genistein was more effective than tyrphostin 25 in attenuating bradykinin-induced responses while the opposite was observed with substance P. Both inhibitors had no significant effects on adenosine (0.5 M)-induced responses (P > 0.5). Collectively, these data suggest that the protein tyrosine kinase metabolic pathway modulates, in part, the edemagenic effects of bradykinin and substance P in the intact hamster cheek pouch microcirculation in a specific fashion.