Updated French guidelines for the therapeutic management of bullous pemphigoid

Burden of Disease of Bullous Pemphigoid: A Targeted Literature Review

BACKGROUND

Bullous pemphigoid (BP) is a rare, chronic, autoimmune, blistering disease characterized by heterogenous lesions including the formation of fluid-filled blisters on frequently flexed areas of the skin and involvement of the mucosa in 10-25% of patients. BP mainly affects older patients and is associated with increased morbidity and mortality. The aim of the targeted literature review was to assess the clinical, humanistic, and economic burden associated with BP.

SUMMARY

Targeted searches were conducted in Embase and MEDLINE for studies published in English up to November 2022 that reported burden of illness of BP. A total of 42 publications on the clinical (n = 37), humanistic (n = 6), and economic (n = 8) burden of BP were identified. BP was associated with a high mortality rate (27-72%) and an increased risk of death compared to matched controls. The majority of patients had at least one comorbidity, including hypertension, diabetes mellitus, stroke, and neurological disorders, and showed severe symptoms such as itching and pain. BP was associated with a negative impact on BP- and pruritus-related quality of life and mental health, with 31% and 38% of patients with BP experiencing depression and anxiety in the "borderline/abnormal" range, respectively. BP was further associated with high economic burden, reflected by increased healthcare resource utilization, such as longer hospital stays (7.3 days in patients with BP vs. 4.7 days in those without BP), and direct disease-related costs.

KEY MESSAGES

This review provides a detailed assessment of the evidence base for BP, characterizing key aspects of the disease burden including clinical, humanistic, and economic burden. The results emphasize that this rare disease is associated with a substantial burden to patients and have implications for clinical practice in the management of BP.

Omalizumab in the treatment of bullous pemphigoid resistant to first-line therapy: a French national multicentre retrospective study of 100 patients

BACKGROUND

Interest in the use of omalizumab to treat bullous pemphigoid (BP) in the event of resistance or contraindication to conventional therapies is currently based on limited evidence.

OBJECTIVES

To assess the effectiveness and safety of omalizumab in BP and to identify predictive factors in response to treatment.

METHODS

We conducted a French national multicentre retrospective study including patients with a confirmed diagnosis of BP treated with omalizumab after failure of one or several treatment lines. We excluded patients with clinically atypical BP, as per Vaillant's criteria. The criteria for clinical response to omalizumab were defined according to the 2012 international consensus conference. Anti-BP180-NC16A IgE enzyme-linked immunosorbent assay was performed on sera collected before initiating omalizumab, when available.

RESULTS

Between 2014 and 2021, 100 patients treated in 18 expert departments were included. Median age at diagnosis was 77 years (range 20-98). Complete remission (CR) was achieved in 77% of patients, and partial remission in an additional 9%. CR was maintained 'off therapy' in 11.7%, 'on minimal therapy' in 57.1%, and 'on non-minimal therapy' in 31.2%. Median time to CR was 3 months (range 2.2-24.5). Relapse rate was 14%, with a median follow-up time of 12 months (range 6-73). Adverse events occurred in four patients. CR was more frequently observed in patients with an increased serum baseline level of anti-BP180-NC16A IgE (75% vs. 41%; P = 0.011). Conversely, urticarial lesions, blood total IgE concentration or eosinophil count were not predictive of CR. Patients with an omalizumab dosage > 300 mg every 4 weeks showed a similar final outcome to those with a dosage ≤ 300 mg every 4 weeks, but control of disease activity [median 10 days (range 5-30) vs. 15 days (range 10-60); P < 0.001] and CR [median 2.4 months (range 2.2-8.2) vs. 3.9 months (range 2.3-24.5); P < 0.001] were achieved significantly faster.

CONCLUSIONS

We report the largest series to date of BP treated by omalizumab and confirm its effectiveness and safety in this indication. Serum baseline level of anti-BP180-NC16A IgE may predict response to treatment.

Autoreactive IgE: Pathogenic role and therapeutic target in autoimmune diseases

Autoimmunity is the break of tolerance to self-antigens that leads to organ-specific or systemic diseases often characterized by the presence of pathogenic autoreactive antibodies (AAb) produced by plasmablast and/or plasma cells. AAb are prevalent in the general population and not systematically associated with clinical symptoms. In contrast, in some individuals, these AAb are pathogenic and drive the development of signs and symptoms of antibody-mediated autoimmune diseases (AbAID). AAb production, isotype profiles, and glycosylations are promoted by pro-inflammatory triggers linked to genetic, environmental, and hormonal parameters. Recent evidence supports a role for pathogenic AAb of the IgE isotype in a number of AbAID. Autoreactive IgE can drive the activation of mast cells, basophils, and other types of FcεRI-bearing cells and may play a role in promoting autoantibody production and other pro-inflammatory pathways. In this review, we discuss the current knowledge on the pathogenicity of autoreactive IgE in AbAID and their status as therapeutic targets. We also highlight unresolved issues including the need for assays that reproducibly quantify IgE AAbs, to validate their diagnostic and prognostic value, and to further study their pathophysiological contributions to AbAID.

Anti-interleukin 4 receptor α antibody for the treatment of Chinese bullous pemphigoid patients with diverse comorbidities and a 1-year follow-up: a monocentric real-world study

Background

Bullous pemphigoid (BP) is a common subepidermal bullous disorder that lacks adequate treatment alternatives. Dupilumab, an anti-interleukin (IL) 4 receptor α antibody blocking Th2 molecules IL-4 and 13, has been used off-label and shown to be effective in refractory BP cases.

Methods

BP patients with various disease severities and comorbidities were included in this case series. All patients received dupilumab alone or in combination with immunosuppressants in a real-world setting. Complete remission (CR) was defined as the absence of pruritus symptoms and previous BP eruptions, with only hyperpigmentation patches and without newly occurring lesions for at least 4 weeks. Disease relapse was classified as the appearance of three or more new lesions within 1 month or at least one large urticarial or eczematous lesion that did not resolve within a week.

Findings

Ten individuals were enrolled in this case series. Pruritus symptoms and BP eruptions improved significantly in nine patients (90%). Seven patients (70%) attained CR, including all mild-to-moderate (100%) cases and three of six (50%) severe BP cases. At the dupilumab monotherapy stage, eosinophilia was observed in two severe cases. One patient out of seven (14.3%) relapsed after 1 year of follow-up after CR.

Conclusion

Treatment of BP with diverse comorbidities with anti-IL-4 receptor α antibody provides further credentials to a prospective randomized study. More impressive efficacy and safety profiles were observed in patients with mild-to-moderate disease after 1 year of follow-up. Eosinophilia may occur in patients receiving dupilumab monotherapy.

Assessment of hydro-saline retention in bullous pemphigoid patients treated with super-potent topical corticosteroids

INTRODUCTION

Super-potent topical corticosteroids (CS) are the mainstay of treatment for bullous pemphigoid. Since super-potent topical CS have systemic effects due to their transcutaneous absorption, we assessed whether super-potent CS were responsible for hydro-saline retention (HSR) in bullous pemphigoid patients.

PATIENTS AND METHODS

From 2015 to 2017, patients with newly-diagnosed bullous pemphigoid treated using clobetasol propionate cream at a starting daily dose of 20 to 40 g were subsequently included in a prospective study. HSR was assessed by longitudinally measuring extracellular water (ECW) volume using bioimpedance analysis (BodyStat QuadScan 4000®) from Day 0 to Day 30 after the initiation of topical CS. Other parameters related to HSR such as weight, blood pressure, natriuresis and proteinuria, were also recorded.

RESULTS

Twenty-nine patients (14 men and 15 women) of mean age 81.8 ± 9.3 years were included and analysed. The mean ECW volume decreased from Day 0 to Day 7 (18.1 ± 4.2 vs 16.7 ± 2.7, p = 0.0094) and was maintained from Day 7 to Day 30 (16.8 ± 2.8 vs 17.0 ± 3.4 L; p = 0.8040). Patient weight loss at Day 30 (69.9 ± 13.6 vs 72.5 ± 14.2 kg, p = 0.0085) was closely correlated with the decrease in ECW volume (r = 0.6740, p < 0.0001). No significant changes in natriuresis, 24-hour proteinuria or blood pressure were observed from Day 0 to Day 30.

CONCLUSION

We found no evidence of HSR in bullous pemphigoid patients treated with super-potent topical CS. Conversely, ECW volume decreased from Day 0 to Day 30, which was correlated with patient weight loss.

Paradoxical phenomena of bullous pemphigoid induced and treated by identical biologics

Objective

This study aimed to investigate the clinical features of biologics-induced bullous pemphigoid (BP) and the therapeutic effects of those agents for BP, exploring the underlying pathophysiological mechanisms.

Methods

We searched PubMed, Web of Science, and Elsevier for studies involving pemphigoid patients treated with or induced by identical biologics published in English from January 2009 to April 2022.

Results

Seventeen cases of drug-induced BP associated with anti-tumor necrosis factor (aTNF)-α therapies, one with interleukin (IL)-17 inhibitors, and seven with IL-12/IL-23 or IL-23 inhibitors were enrolled. Time to cutaneous toxicity varied among different types of agents, and the characteristics of clinical examinations were similar to idiopathic BP. Discontinuation of the culprit drugs and initiation of topical or systemic corticosteroids were adequate in most cases. Several monoclonal antibodies above have also been reported for the treatment of refractory or recurrent BP, especially concurrent with psoriasis.

Conclusion

Biologics for immune-related diseases, including TNF-α, IL-17, and IL-12/IL-23 or IL-23 inhibitors, can both induce and treat BP, which might be associated with a helper T cells Th1/Th2 imbalance, complicated inflammatory networks, and a specific individual microenvironment, suggestive of a new perspective on the therapeutic algorithms of BP. There have been numerous reports about biologics inducing or treating BP. We have taken note of this phenomenon and focused on biologics with both pathogenetic and therapeutic effects on BP. Our review summarized the clinical characteristics of associated cases, trying to figure out the underlying mechanisms of this paradoxical phenomenon and to provide an integrated perspective and new therapeutic alternatives for BP.

Omalizumab as a corticosteroid-sparing agent in the treatment of bullous pemphigoid

Bullous pemphigoid (BP) is the most common autoimmune blistering skin disease, characterized by the development of autoantibodies against hemidesmosomal components BP180 and BP230. The mainstay of therapy is topical and systemic corticosteroids (CS) and immunosuppressors. As this pathology mainly involves the elderly, subjects often have numerous comorbidities that influence the clinical management. Omalizumab is a recombinant humanized monoclonal anti-IgE antibody which has recently emerged as a promising treatment for BP in patients for whom CS are contraindicated or conventional treatments have failed to control the disease. For this study, we selected five patients who presented with corticosteroid-dependent BP with a contraindication to the use of other immunosuppressive treatments. The objectives of our study were to evaluate the effectiveness of omalizumab in controlling BP and allowing to decrease the dosage of systemic CS, assessing the effects of omalizumab on the clinical manifestations and the titers of circulating anti-BP180 and BP230 antibodies, IgE and eosinophils. A reduction in the dose of systemic CS was possible in 100% of the patients and complete resolution of the clinical picture was seen in 100% for skin lesions and in 40% for pruritus. A reduction of circulating IgE was found in 40%, anti-BP180 and BP230 IgGs were decreased in 60% and eosinophils in 80%.

Rapid Disease Control in First-Line Therapy-Resistant Mucous Membrane Pemphigoid and Bullous Pemphigoid with Omalizumab as Add-On Therapy: A Case Series Of 13 Patients

The role of IgE autoantibodies has been demonstrated in the pathogenesis of bullous pemphigoid for many years. Recently, omalizumab (OMZ), a humanized monoclonal anti-IgE antibody that depletes total serum IgE, has been used off-label in a few case series of bullous pemphigoids demonstrating a rapid efficacy and allowing significant improvements or complete remission as add-on therapy in first-line treatment-resistant patients. Herein, we report the largest retrospective study to evaluate OMZ effectiveness in patients with subepidermal autoimmune blistering diseases. Our series included 13 patients from a single center with bullous pemphigoid or mucous membrane pemphigoid, of whom 7 had mucous membrane involvement. OMZ was added to the unchanged immunosuppressive therapies. Detailed clinical and immunological data during the first year were collected, notably for specific anti-BP180-NC16A IgE and IgG, and the median total follow-up was 30 months (range: 3-81). Our series demonstrated that OMZ induced a significant improvement in pruritus, urticarial score, and daily blister count on day 15, allowing disease control to be achieved in a 1-month median time and complete remission (CR) in a 3-month median time in 85% of these patients previously in therapeutic impasse. At the end of the follow-up, 31% of patients achieved CR on minimal therapy after OMZ weaning without relapses, and 54% achieved CR on OMZ continuation with a minimal dose of concomitant treatment. Two patients experienced therapeutic failure (15%). At baseline, clinical variables reflecting activity were significantly positively correlated with eosinophil blood count, total IgE serum level, specific anti-BP180 IgE and IgG. While baseline anti-BP180 IgG and specific anti-BP180 IgE were significantly positively correlated, only the two patients who experienced a therapeutic failure with OMZ did not fit with this correlation, demonstrating elevated levels of anti-BP180 IgG with no measurable BP180-specific IgE. Follow-up of immunological variables demonstrated a rapid decrease of eosinophilia towards normalization, whereas a slower decline towards negativation was observed over 1 year for anti-BP180 IgG and anti BP180 IgE in patients who responded to OMZ. This case series demonstrated that OMZ is a rapidly effective biologic therapy for refractory bullous pemphigoid and mucous membrane pemphigoid, permitting rapid disease control and reduction of concomitant therapeutics.