[Treatment of simultaneously occurring urticaria and atopic dermatitis with dupilumab]

Dupilumab in patients with chronic spontaneous urticaria (LIBERTY-CSU CUPID): Two randomized, double-blind, placebo-controlled, phase 3 trials

BACKGROUND

Chronic spontaneous urticaria (CSU) is a chronic inflammatory disease characterized by recurrent pruritic wheals (hives) and/or angioedema. Patients with CSU could remain symptomatic despite standard-of-care H1 antihistamines (H1-AH) or anti-IgE (omalizumab) treatment. Dupilumab blocks IL-4/IL-13 signaling and is approved for multiple type 2/atopic indications.

OBJECTIVE

We conducted two phase 3, randomized, placebo-controlled, double-blind trials comparing dupilumab with placebo in patients with symptomatic CSU despite H1-AH.

METHODS

In LIBERTY-CSU CUPID Study A, patients were omalizumab-naive (n = 138, aged ≥6 years). In Study B, patients were omalizumab-intolerant/incomplete responders (n = 108, aged ≥12 years). The primary end point was either change from baseline over 7 days in the Urticaria Activity Score (UAS7) or Itch Severity Score (ISS7) at week 24, with the other as a key secondary end point, depending on regional regulatory requirements. Studies were pooled for safety assessment.

RESULTS

In Study A, UAS7 and ISS7 improved with dupilumab versus placebo (difference -8.5 [95% CI, -13.2 to -3.9; P = .0003] and -4.2 [95% CI, -6.6 to -1.8; P = .0005]). In Study B, tested at α = 0.043 after interim analysis, UAS7 improved (difference -5.8 [95% CI, -11.4 to -0.3; P = .0390]), with a numerical trend in ISS7 (difference -2.9 [95% CI, -5.7 to -0.07; nominal P = .0449, not significant]). Pooled safety data were consistent between dupilumab and placebo and with the known dupilumab safety profile.

CONCLUSIONS

Dupilumab reduced urticaria activity by reducing itch and hives severity in omalizumab-naive patients with CSU uncontrolled with H1-AH. Although the primary end point for Study B was not met, dupilumab effects were small in patients who were omalizumab-intolerant/incomplete responders.

Atopy in chronic urticaria: an important yet overlooked issue

Chronic urticaria (CU) is one of the most common dermatological diseases and has a significant impact on the quality of life of patients. However, the pathogenesis of this disease remains unclear. Autoimmunity in chronic spontaneous urticaria (CSU) has received considerable attention and has been studied previously. Atopy is an important characteristic of CU; however, it has not been fully recognized. Atopy predisposes individuals to immune responses to allergens, leading to type 2 inflammation and immunoglobulin E (IgE) overproduction. Compared with healthy individuals, patients with CU have a higher proportion of atopy, and an atopic background is correlated with the clinical characteristics of CU. The total IgE levels in patients with CU is significantly higher than those in healthy individuals. Although its level is not higher than that in classic allergic diseases, it is closely related to CU. Exogenous allergens, auto-allergens, and specific IgEs, which are closely related to atopy, have been reported, and their roles in CU pathogenesis are also being studied. Local and systemic atopic inflammation is present in patients with CU. This review summarizes the current knowledge regarding atopy and CU, speculating that there are CU subtypes, such as atopic CSU or atopic chronic inducible urticaria (CIndU) and that atopy may be involved in the pathogenesis of CU. These findings provide a new perspective for a comprehensive understanding of the clinical features of CU and further research regarding its pathogenesis.

Dupilumab: Advances in the off-label usage of IL4/IL13 antagonist in dermatoses

Type 2 immune response refers to a complicated series of immune responses characterized by Th2 polarization and Th2 cytokines secretion. The IgE secretion, airway hypersensitivity, and effector cell recruitment (eosinophils, mast cells, basophils) in skin lesion and peripheral blood stream could be upregulated during the activation of type 2 immune response. Th1/Th2 ratio, also referred as Th1/Th2 balance, represent the T lymphocytes immune pattern to a certain degree: Th1-dominated responses are often involved in intracellular infections (e.g., mycobacterium tuberculosis) and autoimmune diseases (e.g., Graves' disease) while Th2-dominated responses are involved in allergic conditions (e.g., atopic dermatitis, eczema), IgE mediated diseases (e.g., urticaria), and fibrotic dermatoses (e.g., keloids). Dupilumab, as one of the most widely applied Th2 cytokine inhibitors, could block the bioactivity of IL-14/IL-13 via competitively binding to the common IL-4Rα subunit shared by IL-4 and IL-13 receptors. In addition to the direct inhibition of type 2 response, dupilumab is also effective in autoimmune and some infectious skin diseases through indirect regulation of type 1 immune response. The pathological mechanism of Th2 responses and advanced clinical application of dupilumab in skin diseases will be summarized and discussed in the review.

[Anti-IgE-directed treatment of urticaria in a dermatological practice]

We conducted a retrospective data analysis of 26 patients with chronic spontaneous urticaria (CSU), 12 of whom had been treated with anti-IgE therapy (omalizumab). The subcohort of patients treated with omalizumab displayed more severe and prolonged courses of disease. In addition, they had often undergone various inpatient therapies, frequently presenting with concomitant angioedema. Collecting the Urticaria Activity Scores from the seven daily values for wheals and itching (UAS7) proved an important and suitable instrument for the determination and assessment of the course of therapy in the dermatological office. Elaborate laboratory screenings, however, seem far less indicative of the severity, prognosis and course of the disease. Omalizumab proved to be a viable and well-tolerated treatment option. One third of the patients were completely free of all symptoms, another third showed very good improvement, whereas the last third showed no improvement at all, even when omalizumab and/or concomitant therapies were escalated.

Cholinergic Urticaria, an Effective and Safe "Off Label" Use of Dupilumab: A Case Report with Literature Review

Cholinergic Urticaria (CholU) is a form of generalized urticaria induced by an increase in core body temperature that activates the sweat reflex. Clinically it is characterized by localized and highly itchy wheals with surrounding erythema and can occur in response to exercise, hot baths and/or emotional stress. Dupilumab is a fully human monoclonal antibody specifically designed to simultaneously inhibit the activity of interleukin-4 (IL-4) and interleukin-13 (IL-13), which play a key role in the inflammation cascade of type 2. We report the case of a 26-year-old man suffering from CholU for 3 years, unresponsive to standard treatment in which off-label therapy was undertaken with Dupilumab, 600 mg subcutaneous as a loading dose and then 300 mg every 15 days. The daily Visual Analogue Scale (VAS) score was used to assess the efficacy of the therapy. Already after the first two administrations, the patient no longer had CholU episodes and resumed regular sporting activity, with a marked improvement in the quality of life. A possible mechanism of Dupilumab in reducing the manifestations of CholU is the blocking of the IL-4 pathway and the expression of the high-affinity IgE receptor (FcεR1) on B cells, mast cells (MCs) and basophils. By decreasing the production of FcεR1, the adhesion of IgE to the surface of MCs decreases with consequent reduction of MCs activation and histamine release. Further experience and large-scale studies may be needed to establish whether Dupilumab can be a therapeutic alternative in CholU, especially in patients who do not respond to standard treatment.

The emerging role of dupilumab in dermatological indications

INTRODUCTION

Dupilumab represents a breakthrough in the management of atopic dermatitis (AD), thanks to its powerful T-helper (Th)2-mediated immunity modulating activity. It can reduce the atopic skin molecular signature and induce a significant decrease in the clinical signs and symptoms of AD patients.

AREAS COVERED

Th2 activation has been confirmed or suspected in skin diseases other than AD, and several reports about the treatment with dupilumab in these conditions have been published. In order to review the new indications of dupilumab in dermatology, we performed a search on PubMed, Embase, Cochrane Skin databases, and clinicaltrials.gov.

EXPERT OPINION

The analysis of available literature suggests that dupilumab may have a large application in dermatology, besides AD. Clinical trials are underway on some widespread disease (i.e. chronic urticaria, bullous pemphigoid, alopecia areata, or allergic contact dermatitis). The data are still partial, but they seem to indicate that dupilumab is efficacious and safe. On the other hand, the dupilumab use in some rare skin diseases remains only hypothetical or linked to few case reports. Dupilumab could have a prominent position in the therapeutic algorithm of chronic skin diseases that significantly affect the quality of life of patients, require long-term treatment, or lacking effective therapies.