Generalized pustular psoriasis - a model disease for specific targeted immunotherapy, systematic review

The role of interleukin-36 in health and disease states

The interleukin (IL)-1 superfamily upregulates immune responses and maintains homeostasis between the innate and adaptive immune systems. Within the IL-1 superfamily, IL-36 plays a pivotal role in both innate and adaptive immune responses. Of the four IL-36 isoforms, three have agonist activity (IL-36α, IL-36β, IL-36γ) and the fourth has antagonist activity (IL-36 receptor antagonist [IL-36Ra]). All IL-36 isoforms bind to the IL-36 receptor (IL-36R). Binding of IL-36α/β/γ to the IL-36R recruits the IL-1 receptor accessory protein (IL-1RAcP) and activates downstream signalling pathways mediated by nuclear transcription factor kappa B and mitogen-activated protein kinase signalling pathways. Antagonist binding of IL-36Ra to IL-36R inhibits recruitment of IL-1RAcP, blocking downstream signalling pathways. Changes in the balance within the IL-36 cytokine family can lead to uncontrolled inflammatory responses throughout the body. As such, IL-36 has been implicated in numerous inflammatory diseases, notably a type of pustular psoriasis called generalized pustular psoriasis (GPP), a chronic, rare, potentially life-threatening, multisystemic skin disease characterised by recurrent fever and extensive sterile pustules. In GPP, IL-36 is central to disease pathogenesis, and the prevention of IL-36-mediated signalling can improve clinical outcomes. In this review, we summarize the literature describing the biological functions of the IL-36 pathway. We also consider the evidence for uncontrolled activation of the IL-36 pathway in a wide range of skin (e.g., plaque psoriasis, pustular psoriasis, hidradenitis suppurativa, acne, Netherton syndrome, atopic dermatitis and pyoderma gangrenosum), lung (e.g., idiopathic pulmonary fibrosis), gut (e.g., intestinal fibrosis, inflammatory bowel disease and Hirschsprung's disease), kidney (e.g., renal tubulointerstitial lesions) and infectious diseases caused by a variety of pathogens (e.g., COVID-19; Mycobacterium tuberculosis, Pseudomonas aeruginosa, Streptococcus pneumoniae infections), as well as in cancer. We also consider how targeting the IL-36 signalling pathway could be used in treating inflammatory disease states.

Comparative Efficacy and Safety of Ustekinumab and Secukinumab in the Treatment of Generalized Pustular Psoriasis: A 48-Week Retrospective Cohort Study with Genetic Background Analysis

Purpose

Recent studies have shown that novel biologics may provide significant clinical benefits for patients with generalized pustular psoriasis (GPP). Ustekinumab and secukinumab have been approved in Japan for GPP treatment in adult patients. However, the differences in efficacy and safety of these two drugs in GPP are not known.

Aim

Based on the genetic background, we aimed to compare the efficacy and safety of secukinumab and ustekinumab in patients with GPP.

Methods

Patients with moderate to severe GPP who were treated with ustekinumab/secukinumab at our department from July 2019 to May 2022 were included in this study and followed up for 48 weeks. The difference in efficacy between ustekinumab and secukinumab was evaluated by assessing changes in body temperature, laboratory indices, recovery of skin lesions, and changes in quality of life. Additionally, we collected patients' saliva for genotyping and explored the effect of CARD14 genetic mutations on clinical efficacy.

Results

A total of 65 patients (32 adults and 33 children) with moderate to severe GPP were included in this study. 31 patients received ustekinumab therapy, and 34 patients were treated with secukinumab. Secukinumab demonstrated superiority to ustekinumab, as evidenced by a higher GPPASI 90 response at week 2. Additionally, the efficacy of ustekinumab and secukinumab was found to be independent of the presence of the CARD14 mutation.

Conclusion

Secukinumab is superior to ustekinumab in rapidly clearing the skin and improving health-related quality of life. Moreover, the responses to ustekinumab/secukinumab in patients were not influenced by CARD14 gene mutations.

Indian expert Delphi consensus on the diagnosis and management of flares of generalised pustular psoriasis

Generalised pustular psoriasis (GPP) is a chronic, multisystemic, autoinflammatory disease with predominantly cutaneous manifestations, characterised by recurrent episodes of widespread, macroscopic and aseptic pustules. It has a highly unpredictable, heterogeneous and unstable clinical course. There are no consensus guidelines in India for the management of GPP. The objective of this Delphi panel study was to achieve consensus on problem areas in the understanding and management of GPP. Based on the inputs from an expert panel, 19 topics across six domains were identified as being important regarding the understanding and management of GPP. Statements were developed for these 19 topics, and consensus for the statements was sought using the modified Delphi method. Twelve experts evaluated the statements, indicating their agreement or disagreement. Consensus was considered to be reached when ≥80% of experts agreed with a statement. After two rounds of discussion, consensus was reached for 17 out of 19 (89%) statements and no consensus was achieved for two (11%) statements. We have presented the statements along with the respective degrees of consensus. Wherever relevant, clarifications or additional comments by experts are provided in the document.

Considerations for defining and diagnosing generalized pustular psoriasis

Generalized pustular psoriasis (GPP) is a rare, chronic skin disease, characterized by widespread pustules and erythema, often accompanied with systemic signs and symptoms. GPP flares occur episodically but may be protracted. Left untreated, GPP can be life-threatening. Despite being first reported over 100 years ago, definitions and diagnostic criteria for GPP have been inconsistent and varied due, in part, to its rarity and a limited understanding of its pathogenesis. As such, many patients with GPP face delays in diagnosis and subsequent treatment. This manuscript aims to increase the recognition of GPP and provide foundational considerations to aid in the definition and diagnosis of this disease.

Current Treatments for Generalized Pustular Psoriasis: A Narrative Summary of a Systematic Literature Search

Generalized pustular psoriasis (GPP) is a rare, chronic and potentially life-threatening autoinflammatory skin disease characterized by widespread eruption of sterile pustules, with or without systemic inflammation. GPP can significantly reduce patients' quality of life (QoL). Several therapeutic approaches have been described in the literature, but there is no consensus on optimal treatment. In this review, we summarize published literature on efficacy, safety and QoL outcomes associated with current treatment of GPP with both approved and non-approved products. Embase and MEDLINE databases were searched (1980-September 2023). A search protocol was designed in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines and registered on the PROSPERO database (CRD42021215437). Details on publication, population, intervention, efficacy, safety and QoL were captured and checked by independent reviewers. In total, 118 publications were included, with only 19% of publications reporting on the results of clinical trials. Treatment modalities reported for GPP included non-biologic systemic therapies such as retinoids, cyclosporine and methotrexate, topical agents, biologics and small molecules, among others. Results were highly heterogeneous and methodological quality was very low, with only the interleukin-36R inhibitor spesolimab reporting results from placebo-controlled randomized trials; based on this, spesolimab is now approved for GPP treatment in regions including the USA, Japan, China, the EU and several other countries. Some other biologics are approved exclusively in Japan and Taiwan for the treatment of GPP based on open-label studies with small patient numbers in lieu of double-blind studies. Non-standardization of clinical outcomes across studies remains a major hurdle in reaching a consensus on optimal treatment. However, recently trials have been conducted using well-defined, disease-specific endpoints to evaluate GPP-targeted treatments, which will hopefully advance patient care. In conclusion, this review highlights the need for prospective randomized studies with GPP-specific endpoints to determine the optimal treatment strategy.

New and Emerging Treatments for Generalized Pustular Psoriasis: Focus on IL-36 Receptor Inhibitors

Generalized Pustular Psoriasis (GPP) is a rare and severe subtype of psoriasis that significantly impacts patients' quality of life. Until recently, no specific treatment modalities were available, and treatment for GPP followed the guidelines for the treatment of plaque psoriasis, consisting of conventional treatments, such as retinoids, methotrexate, and even biologics, which although effective in some cases, may be associated with significant side effects, necessitating more effective and safe options. The pathophysiology of Generalized Pustular Psoriasis is complex and not fully understood, but there is some overlap with the pathogenesis of Plaque Psoriasis. In GPP, the innate immune system seems to play a more significant role, with the interleukin (IL)-36 pathway being fundamentally involved. Spesolimab and imsidolimab, two recently developed therapeutic agents, target the IL-36 inflammatory pathway by binding to the IL-36 receptor (IL-36R). Both biologics have already been evaluated in phase 1 and 2 clinical trials and have shown promising results in terms of safety and efficacy. IL-36 receptor inhibitors demonstrated great efficacy and good safety profile in the management of patients with GPP, demonstrating their potential to emerge as a leading treatment option. This review aims to explore and summarize the current scientific literature on the most recently developed treatments for GPP.

Management of Pustular Psoriasis; The Way Ahead

Pustular psoriasis is a specialized variant of psoriasis which can be life threatening if not treated at the earliest. The pathogenesis has been recently linked to the role of interleukin 36. Apart from the corticosteroids, systemic antipsoriatics like acitretin, cyclosporine and methotrexate have been used with some success though unpredictable. With recent identification of role of IL-36 in the pathogenesis of pustular psoriasis, biologics targeting the IL-36 receptors have been used to manage the situation with high degree of success. This narrative review deals with the recent concepts of pathogenesis of pustular psoriasis as well as the current management scenario.

[Translated article] Approach to the Epidemiology, Disease Management, and Current Challenges in the Management of Generalized Pustular Psoriasis Through a Survey Conducted Among Spanish Dermatologists

BACKGROUND

Generalized pustular psoriasis (GPP) is a rare and severe inflammatory skin disease characterised by recurrent or intermittent flares. Epidemiological and disease management data in Spain are limited. Our goal was to estimate the epidemiology of GPP, explore its management, and reach consensus on the current challenges faced in Spain.

METHODS

An electronic survey was submitted to dermatologists from the Spanish Academy of Dermatology and Venereology Psoriasis Working Group. This group is experienced in the management of GPP. It included a Delphi consensus to establish the current challenges.

RESULTS

A total of 33 dermatologists responded to the survey. A 5-year prevalence and incidence of 13.05 and 7.01 cases per million inhabitants, respectively, were estimated. According to respondents, the most common GPP symptoms are pustules, erythema, and desquamation, while 45% of patients present > 1 annual flares. A total of 45% of respondents indicated that flares often require a length of stay between 1 and 2 weeks. In the presence of a flare, 67% of respondents often or always prescribe a non-biological systemic treatment as the first-line therapy [cyclosporine (55%); oral retinoid (30%)], and 45% a biological treatment [anti-TNFα (52%); anti-IL-17 (39%)]. The dermatologists agreed that the main challenges are to define and establish specific therapeutic goals to treat the disease including the patients' perspective on the management of the disease.

CONCLUSION

Our study describes the current situation on the management of GPP in Spain, increasing the present knowledge on the disease, and highlighting the current challenges faced at the moment.

Approach to the Epidemiology, Disease Management, and Current Challenges in the Management of Generalized Pustular Psoriasis Through a Survey Conducted Among Spanish Dermatologists

BACKGROUND

Generalized pustular psoriasis (GPP) is a rare and severe inflammatory skin disease characterised by recurrent or intermittent flares. Epidemiological and disease management data in Spain are limited. Our goal was to estimate the epidemiology of GPP, explore its management, and reach consensus on the current challenges faced in Spain.

METHODS

An electronic survey was submitted to dermatologists from the Spanish Academy of Dermatology and Venereology Psoriasis Working Group. This group is experienced in the management of GPP. It included a Delphi consensus to establish the current challenges.

RESULTS

A total of 33 dermatologists responded to the survey. A 5-year prevalence and incidence of 13.05 and 7.01 cases per million inhabitants, respectively, were estimated. According to respondents, the most common GPP symptoms are pustules, erythema, and desquamation, while 45% of patients present > 1 annual flares. A total of 45% of respondents indicated that flares often require a length of stay between 1 and 2 weeks. In the presence of a flare, 67% of respondents often or always prescribe a non-biological systemic treatment as the first-line therapy [cyclosporine (55%); oral retinoid (30%)], and 45% a biological treatment [anti-TNFα (52%); anti-IL-17 (39%)]. The dermatologists agreed that the main challenges are to define and establish specific therapeutic goals to treat the disease including the patients' perspective on the management of the disease.

CONCLUSION

Our study describes the current situation on the management of GPP in Spain, increasing the present knowledge on the disease, and highlighting the current challenges faced at the moment.

Generalized Pustular Psoriasis, Acute Generalized Exanthematous Pustulosis, and Other Pustular Reactions: A Clinical Review

Generalized pustular rashes have various etiologies and can be challenging to diagnose and manage at first presentation. The authors provide an in-depth analysis of common pustular skin eruptions including generalized pustular psoriasis (GPP) and acute generalized exanthematous pustulosis, focusing on their pathophysiology, triggers, clinical presentation, diagnostic challenges, and management strategies. The article also highlights recent advances in genetic research and biologic therapies for GPP and the future directions in personalized medicine and prevention strategies.

Generalized pustular psoriasis in a toddler with IL36RN mutation: a case report

Generalized Pustular Psoriasis (GPP) is a dermatological autoinflammatory disease that rarely occurs in children and is associated with complex genetic factors. GPP pathogenesis has been associated with mutations in IL36RN gene, which encodes an interleukin-36 receptor antagonist. GPP usually occurs without a history of psoriasis in the patients or their family members. This case report describes the clinical course of a 3-year-old toddler with GPP. The diagnosis of GPP was confirmed through a comprehensive series of examinations, and genetic testing revealed an IL36RN mutation, providing further insight into the genetic basis of the condition. This case highlights the importance of a genetic perspective for diagnosing GPP, particularly in children.

Human Leukocyte Antigen Markers for Distinguishing Pustular Psoriasis and Adult-Onset Immunodeficiency with Pustular Reaction

Pustular skin diseases, with pustular psoriasis (PP) being the prototype, are immune-mediated diseases characterized by the presence of multiple pustules, resulting from neutrophil accumulation in the layer of epidermis. Sterile skin pustular eruption, like PP, is also observed in 20-30% of patients with adult-onset immunodeficiency syndrome (AOID) and anti-interferon γ autoantibodies (IFN-γ), leading to challenges in classification and diagnosis. While the mechanism underlying this similar phenotype remains unknown, genetic factors in relation to the immune system are suspected of playing an important role. Here, the association between human leukocyte antigen (HLA) genes, which play essential roles in antigen presentation, contributing to immune response, and the presence of skin pustules in AOID and PP was revealed. HLA genotyping of 41 patients from multiple centers in Thailand who presented with multiple sterile skin pustules (17 AOID patients and 24 PP patients) was conducted using a next-generation-sequencing-based approach. In comparison to healthy controls, HLA-B*13:01 (OR = 3.825, 95%CI: 2.08-7.035), C*03:04 (OR = 3.665, 95%CI: 2.102-6.39), and DQB1*05:02 (OR = 2.134, 95%CI: 1.326-3.434) were significantly associated with the group of aforementioned conditions having sterile cutaneous pustules, suggesting a common genetic-related mechanism. We found that DPB1*05:01 (OR = 3.851, p = 0.008) and DRB1*15:02 (OR = 3.195, p = 0.033) have a significant association with pustular reaction in AOID patients, with PP patients used as a control. A variant in the DRB1 gene, rs17885482 (OR = 9.073, p = 0.005), was observed to be a risk factor for PP when using AOID patients who had pustular reactions as a control group. DPB1*05:01 and DRB1*15:02 alleles, as well as the rs17885482 variant in the DRB1 gene, were proposed as novel biomarkers to differentiate PP and AOID patients who first present with multiple sterile skin pustules without known documented underlying conditions.

Utility of Dermoscopy in the Diagnosis of Erythroderma: A Cross-Sectional Study

Background

It is difficult to diagnose the underlying cause of erythroderma on mere clinical presentation. The role of dermoscopy in diagnosing erythroderma secondary to various etiologies is evolving.

Aim and Objectives

This study aimed to observe the dermoscopic features of erythroderma secondary to different cutaneous disorders and compare them with clinical features and histopathology.

Materials and Methods

Twenty-nine consecutive patients of erythroderma were enrolled in the study. Dermoscopy was performed on every case using a Heine Delta II Dermatoscope with 10x magnification in polarized mode. A histopathological examination was conducted to confirm the diagnosis.

Results

Eight patients were diagnosed with psoriasis, five with endogenous eczema, four with pityriasis rubra pilaris (PRP), three with pustular psoriasis, two with drug rash secondary to antitubercular therapy, two with dermatophytic infection, one patient each of atopic dermatitis, crusted scabies, pemphigus foliaceous, drug reaction with eosinophilia and systemic symptoms, and mycosis fungoides. Characteristic dermoscopic features were observed in erythroderma due to psoriasis, PRP, pustular psoriasis, endogenous eczema, scabies, and dermatophytosis. Differentiation of other disorders based on dermoscopy alone was difficult, and clinico-histopathological correlation was crucial to reach a diagnosis.

Conclusion

Dermoscopic features of classical patterns of skin disorders are preserved even in the corresponding erythrodermic or unstable stage. Dermoscopic features of erythroderma secondary to psoriasis, pustular psoriasis, PRP, endogenous eczema, scabies, and dermatophytosis are clearly differentiating, whereas the dermoscopic features in other causes of erythroderma are overlapping. Thus, dermoscopy can be a good screening tool in the clinical assessment of erythroderma.

Disease modification in inflammatory skin disorders: opportunities and challenges

Progress in understanding of the mechanisms underlying chronic inflammatory skin disorders, such as atopic dermatitis and psoriasis vulgaris, has led to new treatment options with the primary goal of alleviating symptoms. In addition, this knowledge has the potential to inform on new strategies aimed at inducing deep and therapy-free remission, that is, disease modification, potentially impacting on associated comorbidities. However, to reach this goal, key areas require further exploration, including the definitions of disease modification and disease activity index, further understanding of disease mechanisms and systemic spillover effects, potential windows of opportunity, biomarkers for patient stratification and successful intervention, as well as appropriate study design. This Perspective article assesses the opportunities and challenges in the discovery and development of disease-modifying therapies for chronic inflammatory skin disorders.

Diversity in the clinical presentation of generalized pustular psoriasis (GPP): A series of case vignettes from around the world

A key principle of clinical studies and case reports is that they should reflect the demographics and epidemiology of the patient population concerned. Here, we have compiled a diverse group of clinical cases of generalized pustular psoriasis (GPP) to showcase the differences in GPP presentation in patients worldwide. We attempt to capture the broad spectrum of clinical presentations of GPP and showcase the diversity of the patient population. The patients included in this series are diverse in age, genetic background, skin phototype and medical history. Moreover, they present with a variety of clinical courses of GPP and different degrees of systemic involvement, and experience flares triggered by different inciting factors. The key learnings from this case series may support physicians in identifying and managing patients with this rare and multifaceted disease that can affect patients both physically and psychologically.

Newly revealed variants of SERPINA3 in generalized pustular psoriasis attenuate inhibition of ACT on cathepsin G

Generalized pustular psoriasis (GPP) is an autoinflammatory skin disease whose pathogenesis has not yet been fully elucidated. Alpha-1-antichymotrypsin(ACT) is a protein encoded by the SERPINA3 gene and an inhibitor of cathepsin G. One study of a European sample suggested that the loss of ACT function caused by SERPINA3 mutation is implicated in GPP. However, the role of SERPINA3 in the pathogenesis of GPP in other ethnic populations is unclear. To explore this, seventy children with GPP were performed next-generation sequencing to identify rare variants in the SERPINA3 gene. Bioinformatic analysis and functional tests were used to determine the effects of the variants, and a comprehensive analysis was performed to determine the pathogenicity of the variants and whether they are associated with GPP. One rare deletion and three rare missense variants were identified in the SERPINA3 gene in GPP. The deletion variant c.1246_1247del was found to result in a mutant protein with an extension of 10 amino acids and a C-terminal of 20 amino acids that was completely different from the wild-type. This mutant was found to impede secretion of ACT, thus failing to function as an inhibitor of cathepsin G. Two missense variants were found to reduce the ability of ACT to inhibit cathepsin G enzymatic activity. The association analysis suggested that the deletion variant is associated with GPP. This study identified four rare novel mutations of SERPINA3 and demonstrated that three of these mutations result in loss of function, contributing to the pathogenesis of pediatric-onset GPP in the Asian population.

Efficacy and safety of spesolimab in Asian patients with a generalized pustular psoriasis flare: Results from the randomized, double-blind, placebo-controlled Effisayil™ 1 study

Generalized pustular psoriasis is a potentially life-threatening neutrophilic skin disease characterized by recurrent flares of widespread erythema and eruption of sterile pustules. In the Effisayil™ 1 study (NCT03782792), 53 patients with a generalized pustular psoriasis flare were treated with placebo or spesolimab, a humanized anti-interleukin-36 receptor monoclonal antibody, the first targeted treatment to be studied in a randomized clinical trial. Spesolimab treatment resulted in rapid pustular and skin clearance, with an acceptable safety profile. Here, we evaluate the efficacy and safety of spesolimab in 29 Asian patients in the Effisayil™ 1 study. The primary endpoint, a Generalized Pustular Psoriasis Physician Global Assessment (GPPGA) pustulation subscore of 0 (no visible pustules) at Week 1, was achieved by 10 patients (62.5%) randomized to spesolimab and one patient (7.7%) randomized to placebo (risk difference 54.8, 95% confidence interval [CI] 17.3-79.8). The key secondary endpoint, a GPPGA total score of 0 or 1 (clear or almost clear skin) at Week 1, was achieved by eight (50.0%) and two (15.4%) patients, respectively (risk difference 34.6, 95% CI -3.1-64.7). This was similar to previously published data in the overall population in whom the primary and key secondary endpoints were achieved by 54% versus 6% and 43% versus 11% of patients, respectively. The percentages of Asian patients randomized to spesolimab with a GPPGA pustulation subscore of 0 and GPPGA total score of 0 or 1 were sustained above 60% for up to 12 weeks. In these patients, patient-reported outcomes also improved and markers of systemic inflammation were normalized. Eleven (68.8%) and eight (61.5%) of spesolimab- and placebo-treated patients, respectively, experienced at least one adverse event. In conclusion, spesolimab improved outcomes in Asian patients compared with placebo, supporting its use in the treatment of generalized pustular psoriasis flares.

Targeting IL-17A for the treatment of pustular psoriasis: a comprehensive review

INTRODUCTION

Pustular psoriasis (PP) is a rare subtype of psoriasis. Overall, the growing evidence - in particular for acute generalized PP (GPP) - supports that it is a separate entity with a specific pathogenetic pathway. Interleukin (IL)-17/T-helper 17 (Th17) axis involvement may play an important role in the pathophysiology of PP. Biologicals, often required to achieve clinical remission, have changed the treatment of PP.

AREAS COVERED

We provide the reader with an overview of all the available evidence on the use of the antibody-based therapy targeting IL-17A in patients with PP.

EXPERT OPINION

Although papers reported in this review do not provide definitive evidence (due to methodological limitations) to support the use of IL-17 inhibitors as potential first-line for the treatment of PP, based on our own experience and according to most of the reported literature, targeting IL-17A, may represent the best therapeutical approach in this peculiar clinical spectrum of psoriasis.

Generalized pustular psoriasis is a disease distinct from psoriasis vulgaris: evidence and expert opinion

INTRODUCTION

Generalized pustular psoriasis (GPP) is a rare, severe, clinically heterogeneous disease characterized by flares of widespread, non-infectious, macroscopically visible pustules that occur with or without systemic inflammation, and are associated with significant morbidity and mortality. Historically, GPP has been classified as a variant of psoriasis vulgaris (PV, or plaque psoriasis); however, accumulating evidence indicates that these are distinct conditions, requiring different treatment approaches.

AREAS COVERED

In this perspectives article we review evidence that supports the classification of GPP as distinct from PV.

EXPERT OPINION

The histopathologic and clinical appearance of GPP is distinct from that of PV and fundamental differences exist between the two conditions in terms of genetic causes and expression-related mechanisms of disease development. GPP results from dysregulation of the innate immune system, with disruption of the interleukin (IL)-36 inflammatory pathway, induction of inflammatory keratinocyte responses, and recruitment of neutrophils. PV is driven by the adaptive immune system, with a key role played by IL-17. Considering GPP as a separate disease will enable greater focus on its specific pathogenesis and the needs of patients. Many treatments for PV have insufficient efficacy in GPP and a therapeutic approach developed specifically for GPP might lead to better patient outcomes.

A review of disease burden and clinical management for generalized pustular psoriasis in China

INTRODUCTION

Generalized pustular psoriasis (GPP) is a rare, severe, immune-mediated and potentially life-threatening skin disease. The rarity, differential diagnoses, relapsing nature, skin and systemic symptoms, complications and limited therapeutic approaches for this disease pose a clinical and psychological burden on patients and their families.

AREAS COVERED

Epidemiologic data of GPP in Chinese patients, including the disease prevalence and age of disease onset, as well as epidemiologic data in global populations were reviewed. Multiple proinflammatory cytokines are involved in the disease development and clinical presentation of GPP and the interleukin (IL)-36-mediated signalling pathway play a central role. Furthermore, loss-of-function mutations in IL-36RN (encoding the IL-36 receptor antagonist) are associated with GPP, suggesting a potential drug target for developing a disease-specific therapeutic approach. Biologic agents, including IL-36R targeted agents, are promising treatment options, especially as existing conventional therapies are inadequate. Chinese guidelines for the diagnosis and treatment of psoriasis recommend systemic and topical treatment options for GPP and disease complications, as well as for GPP during pregnancy and juvenile GPP.

EXPERT OPINION

This review summarizes the epidemiology, pathogenesis, clinical characteristics, disease burden and management of patients with GPP in China, and also describes future treatment targets and related clinical trials.

Generalized pustular psoriasis: the new era of treatment with IL-36 receptor inhibitors

Generalized pustular psoriasis (GPP) is a rare yet severe variant of psoriasis, characterized by the eruption of superficial sterile pustules that appear suddenly and widely distributed, potentially life-threatening. It more commonly presents through recurrent acute flares triggered by stress, corticosteroid withdrawals, pregnancy, or infections. The pathogenesis of this disease is yet to be fully understood. Nevertheless, studies have suggested an important role of an IL-1 subfamily of cytokines, due to an imbalance of the IL-36 axis favoring of pro-inflammatory activity. The therapeutic intervention for this condition is still a challenge as its rarity and scarce available information contribute to the absence of specific treatment. Current options stand on small, open-label trials or follows standard treatment for plaque psoriasis. Spesolimab and imsidolimab are two IL-36 receptor inhibitors which completed phase 1 and 2 trials with a good efficacy and safety profile in the treatment of this disease, including in the fast control of its acute flares. The most common adverse events reported with spesolimab were mild to moderate infections, and imsidolimab was well tolerated. GPP clinical trials remain to have their small sample size as a major limitation, but IL-36 receptor inhibitors are promising therapeutic options currently under investigation.

Generalized pustular psoriasis: overview of the status quo and results of a panel discussion

Generalized pustular psoriasis (GPP) is a rare, severe, potentially life-threatening, autoinflammatory, neutrophilic skin disease that may be accompanied by fever and leukocytosis. This paper describes the current state of knowledge on GPP in terms of classification, (differential) diagnosis and prevalence. We present a comparison of the genetics and pathoimmunology of GPP and psoriasis vulgaris with the central mechanisms of autoimmunology and autoinflammation. The currently available therapeutic options, expert recommendations for therapy, and data from early clinical trials investigating targeted therapies will be summarized. We present the results of our discussion with 13 experts for psoriasis vulgaris and GPP and give an integrated overview of indication and therapy based on our personal experience and present an outlook on further research questions. Collectively, this article highlights the high unmet need in GPP, as there exists no satisfactory method of diagnosis or treatment to date and new treatment options will be of great therapeutic benefit to those affected.

Efficacy and Safety of Certolizumab Pegol in Japanese Patients with Generalized Pustular Psoriasis and Erythrodermic Psoriasis: 52-Week Results

Introduction

We report an exploratory analysis of the efficacy and safety of certolizumab pegol (CZP) in Japanese patients with generalized pustular psoriasis (GPP) and erythrodermic psoriasis (EP) (NCT03051217).

Methods

Patients ≥ 20 years with GPP or EP were randomized 1:1 to open-label CZP 400 mg every 2 weeks (Q2W) or 200 mg Q2W (400 mg weeks 0/2/4) for 16 weeks; patients who achieved “much improved” or “very much improved” on the Global Improvement Score (GIS; for GPP) or a PASI 50 response (≥ 50% reduction from baseline Psoriasis Area and Severity Index; for EP) continued to week 52. Efficacy outcomes assessed included Clinical Global Impression of Improvement (CGI-I), Dermatology Life Quality Index (DLQI 0/1), and Itch Numeric Rating Scale (INRS 0). GIS and Japanese Dermatological Association (JDA) severity index were assessed in patients with GPP, and PASI and Physician’s Global Assessment (PGA) in patients with EP. Treatment-emergent adverse events (TEAEs) were evaluated through weeks 0–52.

Results

Of 22 patients randomized, 19 completed week 52. At week 16, all reported outcomes improved with both CZP doses and were generally maintained through week 52. At week 52, 6/7 GPP and 12/12 EP patients achieved CGI-I response (“improved” or “remission”). Also, 4/7 GPP and 7/12 EP patients achieved DLQI 0/1; 2/7 GPP and 2/12 EP patients achieved INRS 0. Meanwhile, 6/7 patients with GPP achieved GIS response, and JDA severity index was reduced from baseline. We found that 9/12 and 5/12 patients with EP achieved PASI 90 and PGA 0/1, respectively. Overall, three serious TEAEs were reported in three CZP 400 mg Q2W-treated patients.

Conclusion

CZP treatment over 16 weeks improved the signs and symptoms of GPP and EP, and improvements were maintained through week 52. No new safety signals were identified.

Trial Registration

ClinicalTrials.gov identifier, NCT03051217.

Supplementary Information

The online version contains supplementary material available at 10.1007/s13555-022-00741-x.

Profiling and multivariate analysis of serum cytokines in patients with generalized pustular psoriasis

Introduction: Generalized pustular psoriasis (GPP) is a chronic autoinflammatory disease characterized by fever, erythema, and sterile pustules occurring over large areas of the skin. The immunopathogenesis of GPP remains poorly understood. We aimed to profile serum cytokine levels in patients with GPP and analyze treatment-associated changes in cytokine levels. Methods: Twenty-four patients who were diagnosed with GPP and received drug treatment, together with 28 unaffected controls, were recruited in this study. Levels of 27 cytokines in serum samples from pre- and post-treated patients as well as unaffected controls were assessed using a Bio-Plex multiplex immunoassay. Multivariate analysis of cytokine levels and clinical parameters was conducted. Results: Serum levels of interleukins interleukin (IL)-1β, IL-1Ra, IL-4, IL-5, IL-6, IL-7, IL-8, IL-10, IL-12 (p70), IL-13, IL-17, granulocyte colony-stimulating factor (G-CSF), interferon-γ (IFN-γ), IFN-γ-induced protein 10 (IP-10), monocyte chemoattractant protein-1, tumor necrosis factor-α, and vascular endothelial growth factor were significantly elevated (p < .05) in patients with GPP compared with controls. Serum levels of IL-6, G-CSF, IL-8, IFN-γ, IL1-Ra, IL-10, IL-13, and IL-1β were correlated with GPP severity (r > 0.4, p < .001). Following treatment, serum levels of IL-6, IL-7, IL-12, IFN-γ, IL-1β, IL-4, IL-8, IL-10, IL-13, G-CSF, and IP-10 were significantly decreased (p < .05) compared with pretreatment levels. Among these cytokines, levels of IL-6, IL-7, IL-8, IL-12, IL-13, and IP-10 were reduced to normal levels. Conclusion: GPP patients exhibited markedly elevated levels of cytokines and chemokines involved in both type 1 and type 2 immune responses, suggesting hypercytokinemia occurs in GPP patients. IL-6 showed the strongest correlation with GPP disease severity and other clinical parameters such as CRP level and fever, thus representing an index for GPP severity. Our data comprehensively documented the cytokine profiles of GPP patients and may provide insights into GPP pathogenesis.

Clinical Course and Characteristics of Generalized Pustular Psoriasis

Generalized pustular psoriasis (GPP) is a rare, potentially life-threatening disease characterized by episodes of widespread sterile macroscopic pustules, with or without systemic inflammation and/or plaque psoriasis. Multiple GPP subtypes have been described, from acute GPP of von Zumbusch to milder, annular pustular psoriasis. Generalized pustular psoriasis mainly affects adults, with a female preponderance, but juvenile GPP also occurs. Flares are a hallmark of GPP and may occur de novo or be provoked by triggers, including withdrawal of systemic corticosteroids, infections, stress, pregnancy, and menstruation. Severity of flares varies widely between patients, and between flares in an individual patient. Significant flares are often accompanied by systemic symptoms, notably fever, general malaise, and extracutaneous manifestations such as arthritis, uveitis, and neutrophilic cholangitis. Common laboratory abnormalities include neutrophilia, elevated C-reactive protein levels, hypocalcemia, and abnormal liver function tests. The clinical course of GPP is highly variable; it can be a relapsing disease with recurrent flares and no pustulation between flares or a persistent disease with perpetual mild pustulation punctuated with flares of greater severity. Patients may have multiple flares per year or a flare every few years. Most flares last 2–5 weeks and approximately 50% require hospitalization. Life-threatening complications include sepsis and renal, hepatic, respiratory, and heart failure. Reported mortality rates are 2–16%.

Diagnosis of Generalized Pustular Psoriasis

Generalized pustular psoriasis (GPP) is a severe rare skin disease characterized by widespread eruption of sterile superficial macroscopic pustules with or without systemic inflammation. Generalized pustular psoriasis flares may lead to life-threatening multiorgan complications, which highlights the need for rapid and accurate diagnosis. However, the rarity of the disease and its heterogeneous cutaneous and extracutaneous symptoms, and the resemblance of symptoms to other skin conditions, pose considerable challenges to the timely diagnosis and treatment of patients with GPP. Current laboratory tests used for GPP diagnosis are generally not GPP specific, and are mainly focused on the assessment of inflammatory markers and clinical and histopathologic features of GPP, and emerging genetic screening approaches. A differential diagnosis to distinguish GPP from other similar conditions requires careful assessment of the patient’s skin symptoms, potential disease triggers, medical history, histopathologic features, laboratory tests, and clinical disease course. The comprehensive interpretation of these assessments can be challenging owing to the lack of standardized global guidelines. While there is currently a lack of standardized international guidelines for the diagnosis of GPP, recent advances in our understanding of the genetics and pathogenesis of the disease have provided new opportunities to enhance diagnosis. In the future, defining specific GPP subtypes using genetic and histopathologic strategies will guide therapeutic decisions, allowing patients to achieve their treatment goals without delay. In this article, we provide an overview of the current diagnostic methods, differential diagnostic strategies, and future advances in the diagnosis of GPP, as well as features of GPP variants.

The Prevalence and Disease Characteristics of Generalized Pustular Psoriasis

Generalized pustular psoriasis (GPP) is a rare disease that has only recently benefited from a consistent definition and clinical coding standard. A lack of disease awareness combined with clinical similarities to other types of psoriasis have historically complicated the diagnosis of GPP. It is now clear that GPP requires a differential diagnosis from psoriasis vulgaris (plaque psoriasis), and better understanding of the genetic characteristics underlying GPP may improve the accuracy of diagnoses in the future. GPP can present at any age but is most common in the fifth decade of life. There appears to be a female preponderance in GPP, although there is notable variability in prevalence by geographical region and between ethnicities. GPP is potentially life-threatening, associated with several serious complications, and may require emergency treatment, particularly for complications arising from systemic inflammation. As with many rare diseases, there are inherent challenges to understanding the epidemiology of GPP. In addition to small patient numbers, estimating the prevalence of rare diseases is further complicated by studies that use non-standardized methodologies and that are conducted in different populations. These complications in data gathering have led to marked variability in GPP case estimates by geographical region and between ethnicities. There is ongoing research into disease characteristics, and insights into regional measures of prevalence are essential to increasing our understanding of GPP.

Pathophysiology of Generalized Pustular Psoriasis

Generalized pustular psoriasis (GPP) is a rare, severe form of pustular psoriasis characterized by widespread, recurrent episodes of neutrophil-rich pustule formation in the epidermis, which can be accompanied by fever and systemic inflammation. Recent clinical, histologic, and genetic evidence indicates that GPP is a distinct entity from plaque psoriasis, with different cytokine pathways predominant in the manifestation of each disease. The interleukin-36 (IL-36) signaling cascade plays a key role in regulating the innate immune system, and its dysregulation appears central to the pathogenesis of GPP. The altered expression of various IL-36 pathway constituents has been shown to cause a positive feedback loop of uncontrolled signaling and excess production of inflammatory cytokines, which in turn leads to chemokine induction and neutrophil recruitment in the epidermis. Given the potentially life-threatening nature of GPP episodes, drug interventions that rapidly achieve disease resolution are required. Early phase data indicate that treatments targeting various components of the IL-36 inflammatory cascade represent promising areas of research. However, there are currently no therapeutic agents specifically approved for GPP in the USA or Europe. Understanding the inflammatory pathways, associated risk factors, and role of neutrophils in the manifestation and perpetuation of GPP flares remains a key goal in developing effective therapeutics. In this article, we summarize the current understanding of GPP, describe novel therapeutic opportunities, and detail how the unique pathophysiology of the disease may inform future treatment strategies.

Unmet Educational Needs and Clinical Practice Gaps in the Management of Generalized Pustular Psoriasis: Global Perspectives from the Front Line

INTRODUCTION

Generalized pustular psoriasis (GPP) is a rare, potentially life-threatening, neutrophilic, autoinflammatory skin disease characterised by recurrent flares of generalised sterile pustules and associated systemic features. Inconsistent diagnostic criteria and a lack of approved therapies pose serious challenges to GPP management. Our objectives were to discuss the challenges encountered in the care of patients with GPP and identify healthcare provider (HCP) educational needs and clinical practice gaps in GPP management.

METHODS

On 24 July 2020, 13 dermatologists from 10 countries (Brazil, Canada, China, Egypt, France, Germany, Japan, Malaysia, the UK and the USA) attended a workshop to share experiences in managing patients with GPP. Educational needs and clinical practice gaps grouped according to healthcare system level were discussed and ranked using interactive polling.

RESULTS

Lack of experience of GPP among HCPs was identified as an important individual HCP-level clinical practice gap. Limited understanding of the presentation and pathogenesis of GPP among non-specialists means misdiagnosis is common, delaying referral and treatment. In countries where patients may present to general practitioners or emergency department HCPs, GPP is often mistaken for an infection. Among dermatologists who can accurately diagnose GPP, limited knowledge of treatments may necessitate referral to a colleague with more experience in GPP. At the organisational level, important needs identified were educating emergency department HCPs to recognise GPP as an autoinflammatory disease and improving communication, cooperation and definitions of roles within multidisciplinary teams supporting patients with GPP. At the regulatory level, robust clinical trial data, clear and consistent treatment guidelines and approved therapies were identified as high priorities.

CONCLUSIONS

The educational imperative most consistently identified across the participating countries is for HCPs to understand that GPP can be life-threatening if appropriate treatment initiation is delayed, and to recognise when to refer patients to a colleague with more experience of GPP management.

Pustular Psoriasis: From Pathophysiology to Treatment

Pustular psoriasis (PP) is a clinicopathological entity encompassing different variants, i.e., acute generalized PP (GPP), PP of pregnancy (impetigo herpetiformis), annular (and circinate) PP, infantile/juvenile PP, palmoplantar PP/palmoplantar pustulosis, and acrodermatitis continua of Hallopeau (ACH), which have in common an eruption of superficial sterile pustules on an erythematous base. Unlike psoriasis vulgaris, in which a key role is played by the adaptive immune system and interleukin (IL)-17/IL-23 axis, PP seems to be characterized by an intense inflammatory response resulting from innate immunity hyperactivation, with prominent involvement of the IL-36 axis. Some nosological aspects of PP are still controversial and debated. Moreover, owing to the rarity and heterogeneity of PP forms, data on prognosis and therapeutic management are limited. Recent progresses in the identification of genetic mutations and immunological mechanisms have promoted a better understanding of PP pathogenesis and might have important consequences on diagnostic refinement and treatment. In this narrative review, current findings in the pathogenesis, classification, clinical features, and therapeutic management of PP are briefly discussed.

Pustular psoriasis flare-up in a patient with COVID-19

INTRODUCTION

The various cutaneous manifestations have lately appeared in the setting of COVID-19. Psoriasis flare-ups have been reported during a COVID-19 infection.

CASE PRESENTATION

We present a case of a 32-year-old woman with COVID-19 who presented with generalized pustular psoriasis. She received oral prednisolone, hydroxyzine, and topical clobetasol. The patient received follow-up two weeks later and found that her lesions were favorably desquamating.

METHODS

The PubMed, SCOPUS, and ISI Web of Science databases were thoroughly searched for English studies reporting psoriasis flare-ups following SARS-CoV-2 infection. Ten case reports/series were included after screening.

CONCLUSIONS

Our case report brings awareness to clinicians for the possible cutaneous manifestation of COVID-19, which should be considered part of the differential diagnoses.

Circulating Metabolomic Signature in Generalized Pustular Psoriasis Blunts Monocyte Hyperinflammation by Triggering Amino Acid Response

Generalized pustular psoriasis (GPP), the most grievous variant of psoriasis, is featured by dysregulated systemic inflammatory response. The cellular and molecular basis of GPP is poorly understood. Blood monocytes are key players of host defense and producers of inflammatory cytokines including IL-1β. How the immune response of monocytes is affected by metabolic internal environment in GPP remains unclear. Here, we performed a metabolomic and functional investigation of GPP serum and monocytes. We demonstrated a significant increase in IL-1β production from GPP monocytes. In GPP circulation, serum amyloid A (SAA), an acute-phase reactant, was dramatically increased, which induced the release of IL-1β from monocytes in a NLRP3-dependent manner. Using metabolomic analysis, we showed that GPP serum exhibited an amino acid starvation signature, with glycine, histidine, asparagine, methionine, threonine, lysine, valine, isoleucine, tryptophan, tyrosine, alanine, proline, taurine and cystathionine being markedly downregulated. In functional assay, under amino acid starvation condition, SAA-stimulated mature IL-1β secretion was suppressed. Mechanistically, at post-transcriptional level, amino acid starvation inhibited the SAA-mediated reactive oxygen species (ROS) formation and NLRP3 inflammasome activation. Moreover, the immune-modulatory effect of amino acid starvation was blocked by silencing general control nonderepressible 2 kinase (GCN2), suggesting the involvement of amino acid response (AAR) pathway. Collectively, our results suggested that decreased serum amino acids in GPP blunted the innate immune response in blood monocytes through AAR pathway, serving as a feedback mechanism preventing excessive inflammation in GPP.

Generalized Pustular Psoriasis: Divergence of Innate and Adaptive Immunity

Generalized pustular psoriasis (GPP) is a severe, relapsing, immune-mediated disease characterized by the presence of multiple sterile pustules all over the body. The exact pathomechanisms behind GPP remain elusive, although increased interest in the genetic basis and immunological disturbances have provided some revealing insights into the underlying signaling pathways and their mutual interaction. The genetic background of GPP has been thoroughly investigated over the past few years. The conducted studies have identified genetic variants that predispose to pustular forms of psoriasis. The loss-of-function mutation of the interleukin 36 receptor antagonist gene, along with rare gain-of-function mutations in the gene that encodes the keratinocyte signaling molecule (CARD14), are examples of the uncovered abnormalities. Interleukin 36 (IL-36), along with neutrophils, is now considered a central cytokine in GPP pathogenesis, with IL-36 signaling providing a link between innate and adaptive immune responses. More recently, a new concept of inflammation, caused by a predominantly genetically determined abnormal activation of innate immune response and leading to inflammatory keratinization, has arisen. GPP is currently considered a representative of this novel group of skin conditions, called autoinflammatory keratinization diseases. As no therapeutic agents have been approved for GPP to date in the United States and Europe, the novel anti-IL-36R antibodies are particularly promising and may revolutionize management of the disease.

Generalized pustular psoriasis: current management status and unmet medical needs in Japan

INTRODUCTION

Generalized pustular psoriasis (GPP) is a rare, inflammatory skin disease characterized by recurrent flares of pustulation accompanied by systemic symptoms that can be life-threatening. The clinical and humanistic burden of GPP in Japan is high, and it is a designated intractable disease. We reviewed clinical evidence and guidelines for GPP treatment in Japan to identify unmet needs and assess data supporting the development and use of new targeted therapies.

AREAS COVERED

Using specific search terms in PubMed and Embase, with additional back-referencing, we retrieved literature related to GPP in Japan focusing on clinical and pathogenic characteristics, diagnosis, and treatment.

EXPERT OPINION

Although there are approved systemic therapies for GPP in Japan, all present uncertainties in terms of safety and efficacy. Clinical evidence supporting their use comes mostly from studies in patients with mild or moderate disease, and their effectiveness in treating acute phase GPP is unknown. The interleukin-36 pathway appears to be central to GPP pathogenesis. New therapies targeting this pathway show promise in patients presenting with acute phase GPP. The rarity and intermittent course of GPP make it challenging to recruit sufficient patients for trials and robustly investigate the efficacy and safety of these agents to treat GPP.

Clinical characteristics and health-care resource utilization in patients with generalized pustular psoriasis using real-world evidence from the Japanese Medical Data Center database

Little is known about the disease burden, health-care resource utilization (HCRU), or treatment of patients with generalized pustular psoriasis (GPP) in Japan. This retrospective cohort study used data from the Japanese Medical Data Center database to compare the demographics, comorbidities, and medication use of patients with GPP and plaque psoriasis and estimate their all-cause HCRU. The patient selection period was from January 1, 2015 to December 31, 2019, and patients must have had at least one confirmed inpatient claim or outpatient claim for GPP or plaque psoriasis. During the 12-month follow-up period, 110 patients with GPP and 20,254 patients with plaque psoriasis were identified. An age- and sex-matched (4:1) comparator control cohort, including members of the general population without a diagnosis of psoriasis (but allowing for a diagnosis of psoriatic arthritis), GPP, or palmoplantar pustulosis, was used. The most prevalent comorbidities in patients with GPP included allergic rhinoconjunctivitis, hypertension, and peptic ulcer disease. Patients with GPP were more likely to experience more comorbidities than those with plaque psoriasis, including asthma, chronic obstructive pulmonary disease, interstitial pneumonia, hyperuricemia and gout, tonsillitis, psoriatic arthritis, other psoriasis, and osteoporosis. Patients with GPP were more likely to be treated with a combination therapy than those with plaque psoriasis (65.5% vs 21.7%, respectively) and less likely to be treated with a topical medication alone (20.9% vs 50.8%). Patients with GPP had more outpatient visits than patients in the plaque psoriasis or matched control cohorts (mean [standard deviation], 14.8 [8.3] vs 11.0 [7.6] and 7.8 [7.2], respectively). They were also more likely to require inpatient hospitalization (24.5% vs 6.4% and 5.0%, respectively). Despite study limitations, patients with GPP in Japan were found to have a higher disease burden, including presence of comorbidities and medication use, than those with plaque psoriasis.

Figurate erythemas - update and diagnostic approach

Figurate erythemas (FE) represent an etiopathophysiologically heterogeneous group of diseases defined by their characteristic annular erythematous skin lesions. Diagnosis is made primarily by clinical examination together with histological findings; often it is a diagnosis made by exclusion. While some authors discuss FE as clinical reaction pattern rather than distinct clinical entities, others identify four classic FE: erythema annulare centrifugum, erythema gyratum repens, erythema migrans and erythema marginatum. The differential diagnoses of FE are numerous and often challenging. We therefore present a potential diagnostic algorithm for FE that discriminates the differentials according to their temporal evolution and the clinical/histological phenotype of the various subtypes. Since some FE may present with an underlying malignancy, diligent clinicians are needed when dealing with those entities.

An update on genetic basis of generalized pustular psoriasis (Review)

Generalized pustular psoriasis (GPP) is a rare and severe auto-inflammatory skin disease that is characterized by recurrent, acute onset, and generalized pustular eruptions on erythematous, inflamed skin. GPP is traditionally classified as a variant of psoriasis vulgaris, even though recent clinical, histological and genetic evidence suggests that it is a heterogeneous disease and requires a separate diagnosis. In recent years, variants of IL36RN, CARD14, AP1S3 and MPO genes have been identified as causative or contributing to genetic defects in a proportion of patients affected by GPP. These disease-related genes are involved in common inflammatory pathways, in particular in the IL-1/IL-36-chemokines-neutrophil pathogenic axis. At present, no standard therapeutic guidelines have been established for GPP management, and there is a profound need for novel efficacious treatments of GPP. Among them, biological agents antagonizing the IL-36 pathway are promising therapeutics. The aim of the present review is to provide the most recent updates on the genetics, genotype-phenotype correlation and pathological basis of GPP, as well as on biologic treatments available for GPP and relative clinical courses.

Study protocol of the global Effisayil 1 Phase II, multicentre, randomised, double-blind, placebo-controlled trial of spesolimab in patients with generalized pustular psoriasis presenting with an acute flare

INTRODUCTION

Generalized pustular psoriasis (GPP) is a rare, potentially life-threatening disease characterised by recurrent flares of widespread neutrophilic aseptic skin pustular eruption. Despite the availability of approved biologics for GPP in Japan, Taiwan and Thailand, associated evidence is largely based on uncontrolled studies in which acute flares were not directly assessed. Therefore, there is a high unmet need to investigate new rapid-acting effective treatments that resolve symptoms associated with acute GPP flares. A prior Phase I proof-of-concept study showed rapid improvements in skin and pustule clearance with a single intravenous dose of spesolimab, a novel anti-interleukin-36 receptor antibody, in patients presenting with an acute GPP flare. Here, we present the design and rationale of Effisayil 1, a global, Phase II, placebo-controlled study to evaluate the efficacy, safety and tolerability of spesolimab in patients presenting with an acute GPP flare.

METHODS AND ANALYSIS

At least 51 patients with an acute GPP flare will be randomised 2:1 to receive a single 900 mg intravenous dose of spesolimab or placebo and followed for up to 28 weeks. The primary endpoint is a Generalized Pustular Psoriasis Physician Global Assessment (GPPGA) pustulation subscore of 0 (pustule clearance) at Week 1. The key secondary endpoint is a GPPGA score of 0 or 1 (clear or almost clear) at Week 1. Safety will be assessed over the study duration by the occurrence of treatment-emergent adverse events. Blood and skin biopsies will be collected to assess biomarkers. Superiority of spesolimab over placebo in the proportion of patients achieving the primary and key secondary endpoints will be evaluated.

ETHICS AND DISSEMINATION

The study complies with the ethical principles of the Declaration of Helsinki, the International Council for Harmonisation's Good Clinical Practice and local regulations. Ethics committee approvals have been obtained for each centre from all participating countries and are listed in online supplementary file 1. Primary results will be published in a peer-reviewed journal.

TRIAL REGISTRATION DETAILS

ClinicalTrials.gov identifier: NCT03782792; Pre-results.

Autoinflammatory syndromes

Autoinflammatory syndromes are a steadily growing group of inflammatory diseases caused by abnormal regulations of the innate immune system. The clinical presentation is multifaceted, but recurrent fever, skin involvement, joint inflammation and other systemic symptoms of inflammation are characteristic. In contrast to classic autoimmune diseases, autoantibodies or specific T cells are not involved in the pathogenesis. In fact, innate immunity plays the most important role in autoinflammation. While activation of the innate immune system is usually self-limiting in healthy individuals, mutations and dysregulation can lead to chronic and excessive activation of innate immune responses and to the development of autoinflammatory diseases.

Drug survival in the treatment of generalized pustular psoriasis: A retrospective multicenter study

Generalized pustular psoriasis (GPP) is a rare, potentially life-threatening inflammatory skin disease. Our aim was to assess patient and disease characteristics and analyze drug survival rates in the treatment of GPP in a real-life setting. In this retrospective study, 201 treatment series of 86 patients with GPP treated at five University Medical Centers were analyzed. Overall, excellent response was reached in 41.3% of all treatment courses, partial response in 31.4%, and nonresponse in 27.3%. Biological treatment was significantly more effective than non-biological therapies (excellent response: 47.4% vs 35.9%; P = .02). Overall, the median drug survival was 14.0 months (biologicals: 36.0 months vs nonbiologicals: 6.0 months; P < .001). The crude probability of survival was highest for secukinumab (hazard ratio [HR] of drug discontinuation compared with acitretin: 0.22), followed by ixekizumab and ustekinumab (HR: 0.38 each), adalimumab (HR: 0.59), etanercept (HR: 0.62), infliximab (HR: 0.69), cyclosporine (HR: 1.00), acitretin (reference for HR), fumaric acid esters (HR: 1.06), methotrexate (HR: 1.26), and apremilast (HR: 3.44); no drug discontinuation with guselkumab. Our results reveal high efficacy and drug survival, particularly for IL-17 and IL-(12)/23 antagonists. Thus, these biologics may be considered early in the therapeutic algorithm of GPP.