Current treatment options for idiopathic angioedema

Omalizumab for Treatment of Idiopathic Angioedema

BACKGROUND

Omalizumab has been shown to improve outcomes in patients with chronic spontaneous urticaria (CSU). Idiopathic angioedema (IAE) is increasingly being recognized as a condition with similar underlying mechanisms as CSU and a form of CSU. We hypothesized that add-on therapy with omalizumab would benefit patients with uncontrolled IAE.

OBJECTIVE

To study the safety and efficacy of omalizumab for the treatment of IAE in adults.

METHODS

We conducted a randomized, placebo-controlled trial to study the efficacy of omalizumab in adults with two or more episodes of angioedema (AE) in the past 6 months for which no clinical or laboratory cause of AE could be found. Ten patients were randomized on a 1:1 basis to receive omalizumab 300 mg SQ or placebo every 4 weeks for 24 weeks with a 12 week follow up period. The primary endpoint was the change in the Angioedema Activity Score (AAS). Secondary endpoints included the Angioedema Quality of Life Questionnaire (AE-QoL), the Visual Analog Scale (VAS) and the number of angioedema episodes per month.

RESULTS

We observed improvement in the AAS score (-2.93 ln odds; 95% confidence interval (CI) -4.84, -1.02; p = 0.003), VAS (-3.49 ln odds; 95% CI -6.58, -0.40; p = 0.03), AE-QoL (-9.43 score; 95% CI -17.63, -1.24; p = 0.028) and number of angioedema episodes per month (-1.93 ln count; 95% CI -3.23, -0.63; p = 0.005) in patients that received omalizumab vs placebo.

CONCLUSION

This study provides preliminary prospective evidence that omalizumab improves outcomes in patients with IAE.

Idiopathic Intestinal Angioedema: A Diagnostic Dilemma

Angioedema is an allergic reaction that usually involves the face and pharynx. Intestinal angioedema is a rare subtype that is typically linked to the use of angiotensin-converting enzymes inhibitors (ACEIs). Intestinal angioedema is challenging to diagnose, as it can mimic gastroenteritis or other inflammatory bowel conditions. Herein, we present a 34-year-old female who presented with recurrent episodes of abdominal pain. She underwent extensive workup for her abdominal pain and rash, and all was unrevealing except for high Immunoglobulin E (Ig E). Multiple imaging came back negative for any pathology. The allergy and immunology team evaluated the patient, and they believed her symptoms are likely caused by isolated intestinal angioedema with a histamine-related rash. She was started on high doses of antihistamines; her symptoms partially improved. Subsequently, she was started on a trial of omalizumab, which resulted in complete resolution of her symptoms. In conclusion, intestinal angioedema is a rare disease that should be suspected in cases of recurrent abdominal pain with negative workup, especially if the patient is taking ACEIs. Few cases were reported in the literature for patients on ACEI. In our case, the diagnosis was a challenge, as the patient was never on ACEI.

Omalizumab for Idiopathic Nonhistaminergic Angioedema: Evidence for Efficacy in 2 Patients

Presently, there is inconclusive evidence regarding the most effective treatment for idiopathic nonhistaminergic acquired angioedema (InH-AAE). Omalizumab may, however, prove to be a promising option. This case report describes two patients who presented with recurrent angioedema attacks, which was refractory to antihistamine therapy. Hence, they were treated with 300 mg omalizumab, every 4 weeks, for a period of 6 months. Both patients had shown a rapid response to the treatment and achieved complete resolution of symptoms without further AE attacks throughout the entire duration of the treatment period. After omalizumab's suspension, one patient remained symptom free for the following 6 months and the other patient had recurrence of symptoms after 2 months for which he was retreated with omalizumab and once again became symptom free. Although omalizumab seems to be effective as a prophylactic treatment for InH-AAE, the determining factors leading to the differences in time-to-relapse between patients after its suspension remain unclear. Further studies are needed in order to better determine the potential therapeutic application of omalizumab and its role in maintenance therapy.

Idiopathic non-histaminergic acquired angioedema: a case series and discussion of published clinical trials

Background

Idiopathic non-histaminergic acquired angioedema (InH-AAE) is a rare disease for which there are no available laboratory parameters to clearly define the disorder. Therapy is often difficult and various treatment options have been proposed. In this paper, we have evaluated the most effective therapies for InH-AAE on the basis of current literature and report the therapeutic effect of omalizumab in three patients with InH-AAE.

Methods

Literature was searched with a combination of MeSH/EMTREE terms and freetext search for angioedema and therapy/omalizumab in the databases Medline (Ovid), PubMed/Premedline, Embase, Cochrane library and Scopus with no time or language restrictions. In three patients affected by InH-AAE the therapeutic effect of omalizumab was demonstrated by clinical outcome. In one patient the FcεRI receptor density on basophils was monitored under therapy with omalizumab.

Results

From the review of the current literature, 25 out of 286 publications dealing with relevant therapeutic recommendations for InH-AAE were analyzed. Six publications with 98 patients referred to tranexamic acid, of which 27 had a complete, 70 a partial and 1 no response. In three case reports ecallantide showed 2 patients with a complete and 1 a partial response. In four case reports for Icatibant 2 had a complete and 3 a partial response. When evaluated in three reports, C1-INH found complete and partial responses in 2 patients each. One patient had a complete response to progestin. Omalizumab was described in 6 reports with 20 patients, all of whom showed a complete response. All three patients described in our study responded to omalizumab with a complete remission. Density of FcεRI receptors on basophils, monitored in patient 1 on a long-term course of 31 months, decreased from 74,051.61 to a minimal level of 1907 receptors per cell.

Conclusions

Omalizumab seems to be the most effective therapy in InH-AAE. The continuous decrease of FcεRI-receptor density on basophils under therapy with omalizumab along with clinical improvement observed in one patient, could serve as a new approach for further studies to evaluate FcεRI-receptor density as a surrogate marker for therapeutic efficacy and for dosing and determining injection intervals of omalizumab.

Trial registration BASEC-Nr. Req-2016-00692. Retrospectively registered 24.11.2016.

Electronic supplementary material

The online version of this article (doi:10.1186/s13601-017-0164-9) contains supplementary material, which is available to authorized users.

Angioedema suppressed by a combination of anti-histamine and leukotriene modifier

Rationale

Angioedema without co-existent urticaria is due to a limited number of causes, including hereditary and acquired C1 esterase inhibitor deficiency, drug-induced angioedema or idiopathic histaminergic or non-histaminergic angioedema. We describe a cohort of patients with recurrent angioedema whose clinical features and response to medications are distinct from the causes above.

Methods

Patients were accrued retrospectively from an academic allergy practice between 2007 and 2014. After institutional research ethics board approval, patients’ charts were reviewed and demographic, clinical and laboratory data were extracted.

Results

A total of 11 patients were recruited. The mean age at presentation was 54.9 years (range 19–70 years) and 6 of 11 were male. The mean number of episodes per year was 18.7 (range 2–60) and mean duration of episodes was 22.4 h (range 4–96). About half of episodes (52%) began overnight. Areas of involvement were lips (73%), tongue (64%), eyelids (18%), feet (36%) and hands (27%). None of the patients had low C3, C4, or CH50; none had significantly positive ANA; C1 esterase inhibitor level and function and C1q were normal in all patients tested. In these 11 patients, complete suppression of recurrences by the combination of cetirizine 20 mg daily and montelukast 10 mg daily was reported by 9 (82%) of patients; whereas 2 (18%) of patients had a partial response to this combination of medications.

Conclusions

Herein, we report a form of angioedema without urticaria, mediated by a combination of histamine and leukotrienes. Clinical, demographic and therapeutic characteristics differentiate this from other recognized causes of angioedema.

Idiopathic Non-histaminergic Angioedema: Successful Treatment with Omalizumab in Five Patients

Idiopathic non-histaminergic acquired angioedema (InH-AAE) is a rare disease characterized by AE resistant to antihistamines and a chronic course. We report five new cases of InH-AAE (two women and three men) with a rapid and dramatic response to the anti-immunoglobulin-E antibody omalizumab. In our literature review, we found 13 other relevant cases with a good response to this treatment. Overall, in 6 out of 18 patients, the doses of omalizumab required to prevent recurrences of attacks were higher than the licensed dose for chronic urticaria. No significant adverse effects have been reported.

Pharmacologic Therapies in Pulmonology and Allergy

Conditions such as chronic rhinitis, urticaria, angioedema, and asthma are frequently seen in clinics and hospitals, and there are a core group of medications that are often used to treat these conditions. Knowing the indications, optimal dosing, and side-effect profile of these medications can improve outcomes. Chronic rhinitis due to various causes is one of the most common reasons for primary care physician visits. Knowing the indications for use, forms of administration, and side-effect profiles of these medications can help improve patient outcomes in these common conditions. This review focuses on the medications used to treat these conditions.