Pustular psoriasis: pathophysiology and current treatment perspectives

Spesolimab: A Review of the First IL-36 Blocker Approved for Generalized Pustular Psoriasis

OBJECTIVE

This article reviews clinical trial data that assesses the safety, efficacy, and clinical application of spesolimab, an interleukin-36 (IL-36) blocker, for the treatment of generalized pustular psoriasis (GPP).

DATA SOURCES

A review of the literature was conducted using the search terms: "spesolimab," "BI 655130," and "spevigo" in MEDLINE (PubMed) and Clinicaltrials.gov from January 1, 1950 to October 31, 2023.

STUDY SELECTION AND DATA EXTRACTION

Relevant articles in English relating to the pharmacodynamics, pharmacokinetics, efficacy, and safety of spesolimab were included.

DATA SYNTHESIS

In one phase 2 clinical trial evaluating single dose IV spesolimab for GPP flares at day 8, 54% of patients receiving spesolimab had a GPP physician global assessment (GPPGA) pustulation subscore of 0, and 43% had a GPPGA total score of 0 compared with 6% and 11% for the placebo group, respectively. Another phase 2 clinical trial assessing subcutaneous spesolimab found 23% of patients in low-dose, 29% in medium-dose, and 10% of high-dose spesolimab had flares by week 48 compared with 52% of the placebo group. Hazard ratios for time to GPP flare compared with placebo were 0.16 (P = 0.0005), 0.35 (P = 0.0057), and 0.47 (P = 0.027) for the spesolimab groups, respectively. Infection rates were similar across treatment and placebo groups, and severe adverse events such as drug reactions with eosinophilia and systemic symptom (DRESS), cholelithiasis, and breast cancer occurred with spesolimab.

RELEVANCE TO PATIENT CARE AND CLINICAL PRACTICE IN COMPARISON TO EXISTING DRUGS

Spesolimab is a first-in-class IL-36 monoclonal antibody receptor antagonist approved for the treatment of acute GPP flares. It is a safe and effective therapeutic agent in preventing future GPP flares, with no current comparator trials with other GPP agents.

CONCLUSION

Spesolimab is a safe and effective treatment for acute GPP flares in adults. Future clinical trials can establish safety and efficacy compared with other agents.

Case report: Successful treatment of acute generalized pustular psoriasis with multiple comorbidities with oral tacrolimus

Acute generalized pustular psoriasis (GPP) is a serious illness. Despite various treatment methods, there is still lack of effective treatment plans for refractory cases with multiple comorbidities. This case report presents a 67-year-old woman with acute GPP, stage 4 chronic kidney disease (CKD), type 2 diabetes, and cardiovascular disease, in whom skin symptom disappearance and kidney function improvement were observed after the use of oral tacrolimus as the sole therapy. This is the first report on the application of tacrolimus in the treatment of acute GPP, especially refractory acute GPP. The successful treatment indicates that there are shared immune pathways between acute GPP and CKD, and the pathways can be interdicted by tacrolimus. Further studies are needed to optimize the therapy to maximize efficacy and minimize toxicity.

Treatment Patterns and Negative Health Outcomes in Palmoplantar Pustulosis Patients in Germany and the US

INTRODUCTION

Limited information exists on the epidemiology, treatment, and burden of palmoplantar pustulosis (PPP) and defining the optimal course of treatment remains challenging without approved targeted treatments in most countries. Here, we describe the clinical and demographic characteristics, treatments received, and negative health outcomes experienced among patients with PPP in the United States (US) and Germany.

METHODS

Retrospective cohort study between 2016 and 2021 using data from the US Merative™ MarketScan® Research Database and IQVIA™ German Disease Analyzer. Adult patients with PPP (ICD-10-CM L40.3) were followed from the date of their first qualifying PPP diagnosis and continued until the earlier of disenrollment or end date of database, during which treatment patterns and incidence rates of negative health outcomes were assessed. Treatment patterns included adherence, non-persistence, discontinuation, re-initiation, switching, and combination therapy.

RESULTS

The prevalence of PPP was 0.005% and 0.065% in the MarketScan database and German Disease Analyzer, respectively, with 1629 and 3866 patients meeting the inclusion criteria. Most patients were female (71.3%, 67.8%), with mean (SD) age of 54.1 (11.7) and 56.9 (14.3) years, respectively. One year post index, most patients received topical treatment (77.4%, 65.3%), but non-persistence and discontinuation were high. Oral and biologic treatments displayed higher levels of adherence, particularly apremilast and tofacitinib among oral treatments and TNF inhibitors and IL-23 inhibitors among biologics. Rates of negative health outcomes were higher among patients not receiving treatment post-index compared with those receiving treatment post-index across both databases, regardless of prior treatment history.

CONCLUSIONS

Establishing treatment guidelines remains an unmet need for patients with PPP and could improve quality of life by reducing the occurrence of negative health outcomes. The findings from this study may provide insight into the effectiveness of current treatment options for patients with PPP and can be leveraged to support the development of treatment guidelines.

Clinical and Disease Burden of Patients with Generalized Pustular Psoriasis: A Review of Real-World Evidence

Generalized pustular psoriasis (GPP) is a chronic, rare, and potentially life-threatening disease. There is limited understanding of patient characteristics in GPP and their correlation with disease progression or healthcare resource utilization. Our review aims to examine real-world evidence on these characteristics and the associated disease burden as related to economic and quality of life factors. Results showed that most patients with GPP experienced flares once a year, lasting from 2 weeks to 3 months, with > 80% of patients having residual disease post-flare, with/without treatment, indicating the long-term nature of GPP. The impact of GPP on patients' daily activities was significant, even in the absence of a flare. GPP adversely affected mental health, and anxiety and depression were reported regularly. Patients with GPP had more comorbidities, were prescribed more medication, and had more inpatient and outpatient visits than in matched plaque psoriasis or general population cohorts. Improving the education of healthcare providers in diagnosing GPP, defining disease flares, and managing the disease, as well as making globally accepted clinical guidelines for GPP treatment available, could help to reduce the burden on patients with GPP. Effective therapies that control and prevent GPP flares and manage chronic disease are needed.

Pustular psoriasis: A distinct aetiopathogenic and clinical entity

Pustular psoriasis is a distinct subset of psoriasis that presents with involvement of the skin in the form of sterile pustules along with systemic manifestations. Though it has been conventionally grouped under the umbrella of psoriasis, recent research has shed light on its pathogenetic mechanisms associated with the IL-36 pathway, which is distinct from conventional psoriasis. Pustular psoriasis in itself is a heterogeneous entity consisting of various subtypes, including generalised, localised, acute, and chronic forms. There is confusion regarding its current classification as entities like deficiency of IL-36 antagonist (DITRA) which are closely related to pustular psoriasis both in their pathogenetic mechanism and its clinical manifestations, are not included under pustular psoriasis. Entities like palmoplantar pustulosis, which presents with similar clinical features but is pathogenetically distinct from other forms of pustular psoriasis, are included under this condition. Management of pustular psoriasis depends upon its severity; while some of the localised variants can be managed with topical therapy alone, the generalised variants like Von Zumbusch disease and impetigo herpetiformis may need intensive care unit admission and tailor-made treatment protocols. The advent of newer biologics and better insight into the pathogenesis of pustular psoriasis has opened the way for newer therapies, including tumour necrosis factor-alpha inhibitors, interleukin-1 inhibitors, interleukin-17 inhibitors, and granulocyte monocyte apheresis. It continues to be an enigma whether pustular psoriasis is actually a variant of psoriasis or an entirely different disease entity, though we feel that it is an entirely different disease process.

Autoinflammatory Keratinization Diseases-The Concept, Pathophysiology, and Clinical Implications

Recent advances in medical genetics elucidated the background of diseases characterized by superficial dermal and epidermal inflammation with resultant aberrant keratosis. This led to introducing the term autoinflammatory keratinization diseases encompassing entities in which monogenic mutations cause spontaneous activation of the innate immunity and subsequent disruption of the keratinization process. Originally, autoinflammatory keratinization diseases were attributed to pathogenic variants of CARD14 (generalized pustular psoriasis with concomitant psoriasis vulgaris, palmoplantar pustulosis, type V pityriasis rubra pilaris), IL36RN (generalized pustular psoriasis without concomitant psoriasis vulgaris, impetigo herpetiformis, acrodermatitis continua of Hallopeau), NLRP1 (familial forms of keratosis lichenoides chronica), and genes of the mevalonate pathway, i.e., MVK, PMVK, MVD, and FDPS (porokeratosis). Since then, endotypes underlying novel entities matching the concept of autoinflammatory keratinization diseases have been discovered (mutations of JAK1, POMP, and EGFR). This review describes the concept and pathophysiology of autoinflammatory keratinization diseases and outlines the characteristic clinical features of the associated entities. Furthermore, a novel term for NLRP1-associated autoinflammatory disease with epithelial dyskeratosis (NADED) describing the spectrum of autoinflammatory keratinization diseases secondary to NLRP1 mutations is proposed.

Exploring the Clinical Assessment, Guidelines, and Options for the Treatment of Generalized Pustular Psoriasis [Podcast]

Acute episodes of generalized pustular psoriasis (GPP), known as "flares", are characterized by the widespread appearance of pustules with surrounding skin erythema, and are often accompanied by systemic symptoms. The clinical course of GPP is unpredictable, and symptoms vary in extent and severity; the disease may be relapsing-remitting with recurrent episodes of pustulosis, or be more persistent. The triggers that may lead to flares include withdrawal of corticosteroids, stress, pregnancy, and infections. GPP-specific assessment tools, such as the Generalized Pustular Psoriasis Physician Global Assessment (GPPGA) and the General Pustular Psoriasis Area and Severity Index (GPPASI), were developed to evaluate the severity of disease, and to monitor the patient's response to therapy during clinical trials. Spesolimab is the first GPP-specific treatment available in the United States for the treatment of GPP flares in adults, and was approved by the US FDA in September 2022. To date, spesolimab has been approved by regulatory agencies in almost 40 countries, including Japan, Mainland China, and the European Union. Spesolimab is a first-in-class humanized monoclonal antibody that targets the interleukin-36 receptor, and blocks the downstream effects of the interleukin-36 pathway, which is associated with GPP pathogenesis. Data from clinical trials demonstrate the safety and efficacy of spesolimab in providing rapid clinical improvement for patients with GPP flares. Standardized international guidelines for the diagnosis and management of GPP are needed, and no recent GPP guidelines are available in the US. This podcast discusses clinical assessment tools for GPP (GPPGA and GPPASI), the evolution of GPP management guidelines, the therapeutic landscape of GPP, efficacy and safety data for spesolimab, and examines important considerations for patients living with this condition.

Current management of generalized pustular psoriasis

Generalized pustular psoriasis (GPP) is a rare subset of psoriasis involving episodes of sterile pustules accompanied by inflammation and, often, systemic involvement. The inflammatory nature of GPP has potential for severe multisystem complications including high-output cardiac failure, infections, digestive system issues, and disfiguring or lethal acute flare episodes. The disease tends to have higher prevalence in females and Asians. The IL-1/IL-36 inflammatory pathway is a critical facet of GPP's pathology. Genetic mutations that are associated with GPP include modifications of Interleukin 36 Receptor Antagonist (IL36RN), Caspase Recruitment Domain Family Member 14 (CARD14), Adaptor Related Protein Complex 1 Subunit Sigma 3 (AP1S3), Myeloperoxidase (MPO) and Serpin Peptidase Inhibitor Clade A Member 3 (SERPINA3) genes. Treatment guidelines for GPP are not well-entrenched. Currently, only one GPP-specific treatment, the interleukin-36 receptor antagonist (IL-36Ra) spesolimab, has been approved for use in the United States. Additional anti-IL-36 pathway therapies are currently being developed. Other treatment options include other biologic therapies such as IL-17 inhibitors, IL-23 inhibitors and TNFα inhibitors. Non-biologic therapeutic options include retinoids, cyclosporine and methotrexate. Treatment options differ throughout the world; most countries utilize retinoids, cyclosporine and methotrexate as first-line non-biologic options. China and United Kingdom have no GPP-specific biologic therapies approved for use, while several biologic therapies are approved for use in Japan. This review aims to serve as an update on the current global management of GPP while also including relevant aspects of disease pathogenesis, diagnosis, clinical presentation, histopathology, aetiology and epidemiology.

Pathophysiology of generalized pustular psoriasis

Psoriasis is a chronic, immune-mediated skin disease that affects over 3% of adults in the United States. Psoriasis can present in several clinical forms. Of these, generalized pustular psoriasis is an acute, severe form, associated with increased morbidity and mortality. Unlike the more common plaque psoriasis, which is thought to feature dysregulation of the adaptive immune system, generalized pustular psoriasis reflects heightened autoinflammatory responses. Recent advances in genetic and immunological studies highlight a key role of the IL-36 immune axis in the pathogenesis of generalized pustular psoriasis. In this article, we review the psoriatic subtypes and discuss diagnostic criteria of generalized pustular psoriasis, discuss several newly identified genetic variants associated with pustular disease in the skin, and discuss how these mutations shed light on pustular disease mechanisms. Furthermore, we gather insights from recent transcriptomic studies that similarly implicate a pathogenic role of the IL-36 immune axis in generalized pustular psoriasis.

Case report: Successful treatment of acute generalized pustular psoriasis of puerperium with secukinumab

Generalized pustular psoriasis (GPP) is a rare and severe form of psoriasis presenting with erythematous, aseptic pustules. Common systemic symptoms include fever and myalgias. The presentation of GPP resembles acute generalized exanthematous pustulosis (AGEP). However, the treatment of these two pathologies differs. While AGEP is self-limiting and treated with topical corticosteroids and constrain of systemic steroids. GPP treatment avoids corticosteroid, choosing acitretin, methotrexate, and cyclosporine as first-line agents. In this case report, a 27-year-old female with a medical history of AGEP presented to the hospital with extensive erythema and pustules. Complete blood count acute phase reactant analysis revealed an elevated white blood cell count and C-reactive protein (CRP). Two histopathological examinations revealed psoriatic hyperplasia of the epidermis with keratosis, along with Kogoj and Munro micro abscesses above the spina layer. Lymphocytic and neutrophilic infiltrate was present in the superficial derma layer along with vasodilation. The patient was diagnosed with GPP according to pathological and clinical criteria. Treatment was initiated with secukinumab because of the patient's failure to respond to systemic treatment with Acitretin, methotrexate, and cyclosporin. Following 2 weeks of therapy with 300 mg of secukinumab, the pustular lesions had resolved. This study indicates the potential efficacy of secukinumab as an effective therapy that can rapidly improve the clinical symptoms of GPP.

Pustular psoriasis with a focus on generalized pustular psoriasis: classification and diagnostic criteria. An Italian expert consensus

Generalized pustular psoriasis (GPP) is a severe and life-threatening systemic disease associated with significant morbidity and mortality. Recent progress has been made in understanding the pathogenetic pathways involved in GPP and an intricate interaction between innate and adaptive immune mechanisms has been suggested. Despite formal consensus guidelines on pustular psoriasis currently available in the literature, the definitions and classifications of GPP used across studies were inconsistent. Consequently, there are no unified criteria that can be universally adopted for precise diagnosis, classification and effective treatment of GPP patients with new targeted drugs. The aim of this review was to collect all the main evidence on available diagnostic criteria for GPP and to establish recommendations in order to promote a better stratification and therapeutic management of this severe and heterogeneous disease.

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.

Generalized Pustular Psoriasis in Pregnancy: Current and Future Treatments

Generalized pustular psoriasis (GPP) is a rare, severe neutrophilic skin disease characterized by sudden widespread eruption of sterile pustules with or without systemic symptoms. GPP may be life threatening in cases with severe complications such as cardiovascular failure, acute respiratory distress syndrome, and serious infections. Impetigo herpetiformis (IH) is a GPP that is induced and exacerbated by pregnancy and occurs most frequently during the last trimester. IH may result in poor or fatal neonatal outcomes, including placental insufficiency, fetal abnormalities, stillbirth, and early neonatal death. Most patients have prompt remission in the postpartum period; however, earlier appearance and more severe symptoms are observed during subsequent pregnancies. Appropriate treatment and close monitoring of the mother and fetus are vital for the management of patients with IH. Particular attention is required for the management of patients with IH to avoid an influence on the fetus. However, data regarding treatments for GPP in pregnant women are sparse. Over the last decade, many patients with IH have been treated with cyclosporine, corticosteroids, tumor necrosis factor-α inhibitors, interleukin (IL)-17 and IL-12/23 inhibitors, and granulocyte and monocyte adsorption apheresis (GMA). GMA may be an important option for patients with IH as it is presently one of the safest available therapeutic options, but there have been no reports to fully confirm its safety in pregnant patients with GPP. Alternatively, based on recent advances in the understanding of the role of the IL-36 axis in the pathogenesis of GPP, biologic agents that target the IL-36 pathway may demonstrate promising efficacy in IH.

Economic Burden of Generalized Pustular Psoriasis in Sweden: A Population-Based Register Study

Background

Generalized pustular psoriasis (GPP), which can occur with or without psoriasis vulgaris (PV), is a severe form of pustular psoriasis with potentially life-threatening symptoms. GPP is also associated with several comorbidities, which further adds to the burden of disease. This study investigates the economic burden of disease in patients with GPP.

Methods

All-cause and GPP-specific healthcare resource use (inpatient stays, physician visits and drug use), as well as associated costs, were compared for year 2015 between GPP patients (n = 914) and two matched control groups representing the general population (n = 4047) and patients with PV but no GPP (n = 2556). Information on resource use for 2015 was obtained from the Swedish National Patient Register and Swedish Prescribed Drug Register, respectively.

Results

All-cause inpatient stays, physician visits, and use of psoriasis-related drugs were significantly more common among GPP patients compared to both control groups. This difference was reflected in total direct cost for GPP patients (5062 euros/year) which was 3.1 and 1.8 times higher (p < 0.001) compared to the general population and PV controls, respectively. For GPP patients, the share of total cost was 22% for all-cause physician outpatient visits and 40% for all-cause inpatient stays. However, only 6.3% and 11.3% of these costs, respectively, were due to GPP-specific problems. Psoriasis-related drugs constituted 27% of total costs for GPP patients of which a large fraction (86%) was represented by biologics.

Conclusion

This study demonstrates a higher economic burden for GPP patients compared to both the general population and patients with PV, with inpatient visits and use of biologic drugs as major cost driving factors. Only fractions of the costs for physician visits and inpatient stays were attributable to specific GPP problems, indicating a higher economic burden of GPP-consequences and complications.

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.

Cutaneous and Systemic Psoriasis: Classifications and Classification for the Distinction

Psoriasis is a chronic multisystem inflammatory disease that affects ~0.1–1.5% of the world population. The classic cutaneous manifestation of psoriasis is scaly erythematous plaques, limited or widely distributed. Moreover, psoriasis could be associated with comorbidities like psoriatic arthritis, metabolic syndrome, diabetes, cardiovascular disease, nephropathy, bowel disease, and brain diseases. In this review, we suggest that psoriasis should be classified as cutaneous psoriasis or systemic psoriasis and propose the classification for distinction. This would help to better understand and manage psoriasis.

A Randomized, Double-Blind, Placebo-Controlled, Phase 2a Study to Evaluate the Efficacy and Safety of RIST4721 in Subjects with Palmoplantar Pustulosis

Introduction

Palmoplantar pustulosis (PPP) is a chronic inflammatory skin condition with neutrophilic infiltration of the epidermis. RIST4721 antagonizes CXC chemokine receptor type 2, which is important in neutrophil recruitment and migration. In this study, the efficacy and safety of RIST4721 versus placebo were assessed in adult subjects with moderate to severe PPP.

Methods

This phase 2a, multicenter, randomized, double-blind, placebo-controlled study investigated RIST4721 versus placebo in subjects with moderate to severe PPP. Key eligibility criteria included: Palmoplantar Pustulosis Area and Severity Index (PPPASI) ≥ 8 and Palmoplantar Pustulosis Physician Global Assessment ≥ 3. Subjects were randomized 1:1 to RIST4721 300 mg or placebo once daily for 28 days. The primary efficacy endpoints were relative change from baseline in fresh and total pustule count at day 28.

Results

Fifteen subjects received RIST4721 and 19 subjects received placebo. Treatment with RIST4721 was found to be generally well tolerated. At day 28, the mean ± standard deviation (SD) relative change from baseline in fresh pustule count was 0.86 ± 0.692 and 0.53 ± 0.561 (P = 0.240) and in total pustule count was 0.99 ± 0.667 and 0.96 ± 0.672 (P = 0.804) for RIST4721 and placebo groups, respectively. Subgroup analysis of subjects with progressing disease demonstrated that subjects with a PPPASI-50 at day 28 was significantly higher for subjects treated with RIST4721 (71%) than placebo (15%) (P = 0.022).

Conclusion

Preliminary data suggest RIST4721 is well tolerated and may be a potential therapy for patients with PPP.

Trial Registration

RIST4721-201 was registered in June 2019 at clinicaltrials.gov: NCT03988335.

Supplementary Information

The online version contains supplementary material available at 10.1007/s13555-021-00632-7.

Psoriasis: a brief overview

Psoriasis is a clinically heterogeneous lifelong skin disease that presents in multiple forms such as plaque, flexural, guttate, pustular or erythrodermic. An estimated 60 million people have psoriasis worldwide, with 1.52% of the general population affected in the UK. An immune-mediated inflammatory disease, psoriasis has a major genetic component. Its association with psoriatic arthritis and increased rates of cardiometabolic, hepatic and psychological comorbidity requires a holistic and multidisciplinary care approach. Psoriasis treatments include topical agents (vitamin D analogues and corticosteroids), phototherapy (narrowband ultraviolet B radiation (NB-UVB) and psoralen and ultraviolet A radiation (PUVA)), standard systemic (methotrexate, ciclosporin and acitretin), biologic (tumour necrosis factor (TNF), interleukin (IL)-17 and IL-23 inhibitors) or small molecule inhibitor (dimethyl fumarate and apremilast) therapies. Advances in the understanding of its pathophysiology have led to development of highly effective and targeted treatments.

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.

Acrodermatitis Continua of Hallopeau Evolving into Generalized Pustular Psoriasis Following COVID-19: A Case Report of a Successful Treatment with Infliximab in Combination with Acitretin

The global pandemic of coronavirus disease 2019 (COVID-19) caused by the novel severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is emerging. Various cutaneous manifestations have been observed in patients with SARS-CoV-2 infection, yet exacerbations of psoriasis have been reported sporadically. Acrodermatitis continua of Hallopeau (ACH) is an uncommon, sterile pustular dermatosis involving one or more digits. In some rare cases, ACH may evolve into generalized pustular psoriasis (GPP), which is a severe, and potentially life-threatening, form of psoriasis that manifests itself with widespread eruptions of pustules. We describe the first case of a patient in whom ACH abruptly progressed into GPP during COVID-19. A combination of infliximab and acitretin was used allowing swift clinical improvement.

Spesolimab, an Anti-Interleukin-36 Receptor Antibody, in Patients with Palmoplantar Pustulosis: Results of a Phase IIa, Multicenter, Double-Blind, Randomized, Placebo-Controlled Pilot Study

Introduction

Palmoplantar pustulosis (PPP) is a chronic, inflammatory skin disease, with high disease burden, that is often refractory to treatment. There is a high unmet clinical need for the treatment of patients with PPP. The objectives of this study were to evaluate the safety and efficacy of spesolimab, a novel anti-interleukin-36 receptor antibody, in patients with PPP.

Methods

This was a phase IIa, multicenter, double-blind, randomized, placebo-controlled pilot study comparing 900 mg spesolimab (n = 19), 300 mg spesolimab (n = 19), and placebo (n = 21) administered intravenously every 4 weeks until week 12 in patients with PPP. The primary efficacy endpoint was the achievement of Palmoplantar Pustulosis Area and Severity Index 50 (PPP ASI50) at week 16, defined as achieving an ≥ 50% decrease from baseline PPP ASI.

Results

At week 16, 31.6% of patients in both spesolimab dose groups achieved PPP ASI50 versus 23.8% receiving placebo (risk difference 0.078; 95% confidence interval –0.190, 0.338). Thus, the primary endpoint was not met. Spesolimab was well tolerated with no clinically relevant treatment-emergent safety signals observed.

Conclusions

PPP severity declined over time in all treatment groups after the start of treatment, with a faster decline in the spesolimab arms than in the placebo arm, indicating a potential treatment effect for spesolimab. Limitations to the study included a small sample size and lower overall disease severity than expected at baseline. It is possible that the primary efficacy endpoint may have coincided with natural disease resolution in some patients. Further effects of the efficacy of spesolimab in PPP are being explored in a phase IIb trial.

Supplementary Information

The online version contains supplementary material available at 10.1007/s13555-021-00504-0.

IgA nephropathy in a patient receiving infliximab for generalized pustular psoriasis

Background

IgA nephropathy is the most common glomerulonephritis. Secondary IgA nephropathy complicated with systemic diseases, including psoriasis, is also often reported. Generalized pustular psoriasis is a form of psoriasis characterized by sterile pustules on reddened skin and fever. Infliximab, one of the first-line therapies for severe psoriasis, has also been reported to cause systemic vasculitis and IgA nephropathy. We herein report a case of IgA nephropathy activated during infliximab treatment for generalized pustular psoriasis.

Case presentation

A 28-year-old woman presented with episodic gross hematuria, increasing proteinuria, and renal dysfunction. She had been receiving anti-TNFα therapy with infliximab because of generalized pustular psoriasis for 3 years, but her skin symptoms worsened following withdrawal during pregnancy. After delivery, her skin symptoms improved with the resumption of infliximab, but clinical signs suggested glomerulonephritis, and renal biopsy showed active IgA nephropathy. Infliximab was discontinued, and the combination of corticosteroids, tonsillectomy, and secukinumab, an IL-17A inhibitor, improved both the skin symptoms and the glomerulonephritis.

Conclusions

In our case, the activity of IgA nephropathy was exacerbated by anti-TNFα therapy but was improved by the combination of corticosteroids, tonsillectomy, and an IL-17A inhibitor against the original disease. Autoimmune diseases may underlie the development of secondary IgA nephropathy associated with anti-TNFα therapy, and so further studies are needed to better understand the association between molecular-targeted drugs and IgA nephropathy.

The role of xenobiotics in triggering psoriasis

Psoriasis is a common inflammatory skin disease affecting approximately 2% of the world population. A complex interplay of genetic predisposition and risk factors contributes to the risk of its onset. Several xenobiotics have been implicated in the pathogenesis of psoriasis. Drugs are among the most investigated trigger factors; strong association with disease induction or exacerbation has been reported for β-blockers, lithium, NSAIDs and ACE inhibitors, all of which are commonly used in the management of various comorbidities in psoriasis patients. Furthermore, inhibitors of TNF have a well-documented potential for triggering new-onset psoriasis when used for other indications (e.g. Crohn's disease or rheumatoid arthritis), while post-marketing data have revealed the same association for ustekinumab. Several other drugs have been connected with psoriasis, but the evidence is less compelling. Smoking and alcohol have been reported to increase the risk for occurrence of psoriasis, but can also affect unfavorably the course of the disease and its response to treatment. Furthermore, exposure to secondhand smoke, especially in childhood, also mediates the risk. Emerging data now suggest that air pollution also has a detrimental effect on skin disease, including psoriasis, but this association needs further investigation. Understanding of the toxic effect of xenobiotics on the initiation and clinical course of psoriasis can contribute to its better control, as it can help with the avoidance of triggering factors and, in some cases, influence the success of pharmacological treatment. It, therefore, has an important place in the comprehensive management of psoriasis.

Dithranol targets keratinocytes, their crosstalk with neutrophils and inhibits the IL-36 inflammatory loop in psoriasis

Despite the introduction of biologics, topical dithranol (anthralin) has remained one of the most effective anti-psoriatic agents. Serial biopsies from human psoriatic lesions and both the c-Jun/JunB and imiquimod psoriasis mouse model allowed us to study the therapeutic mechanism of this drug. Top differentially expressed genes in the early response to dithranol belonged to keratinocyte and epidermal differentiation pathways and IL-1 family members (i.e. IL36RN) but not elements of the IL-17/IL-23 axis. In human psoriatic response to dithranol, rapid decrease in expression of keratinocyte differentiation regulators (e.g. involucrin, SERPINB7 and SERPINB13), antimicrobial peptides (e.g. ß-defensins like DEFB4A, DEFB4B, DEFB103A, S100 proteins like S100A7, S100A12), chemotactic factors for neutrophils (e.g. CXCL5, CXCL8) and neutrophilic infiltration was followed with much delay by reduction in T cell infiltration. Targeting keratinocytes rather than immune cells may be an alternative approach in particular for topical anti-psoriatic treatment, an area with high need for new drugs.

Acrodermatitis continua of Hallopeau: clinical perspectives

Acrodermatitis continua of Hallopeau (ACH) is a rare, sterile pustular eruption of one or more digits. The condition presents with tender pustules and underlying erythema on the tip of a digit, more frequently arising on a finger than a toe. As far as classification, ACH is considered a localized form of pustular psoriasis. The eruption typically occurs after local trauma or infection, but such a history is not always present and various other etiologies have been described including infectious, neural, inflammatory, and genetic causes. The natural progression of ACH is chronic and progressive, often resulting in irreversible complications such as onychodystrophy that can result in anonychia, as well as osteitis that can result in osteolysis of the distal phalanges. Because of the rarity of ACH, there have been no randomized controlled studies to evaluate therapies, resulting in an absence of standardized treatment guidelines. In clinical practice, a wide variety of treatments have been attempted, with outcomes ranging from recalcitrance to complete resolution. In recent years, the introduction of biologics has provided a new class of therapy that has revolutionized the treatment of ACH. Specifically, rapid and sustained responses have been reported with the use of anti-tumor necrosis factor agents like infliximab, adalimumab, and etanercept; IL-17 inhibitors like secukinumab; IL-12/23 inhibitors like ustekinumab; and IL-1 inhibitors like anakinra. Nevertheless, there remains a considerable need for more research into treatment for the benefit of individual patients with ACH as well as for the clinical knowledge gained by such efforts. The purpose of this review is to provide a comprehensive overview of the key features of ACH as well as a discussion of clinical management strategies for this unique and debilitating condition.

Diagnosis and screening of patients with generalized pustular psoriasis

Generalized pustular psoriasis (GPP) is a rare and potentially life-threatening variant of psoriasis that is characterized by recurrent, acute onset, widely distributed pustular eruptions on inflamed, erythematous skin. It is important to recognize acute GPP as a subtype of psoriasis associated with high morbidity and mortality so therapy can be initiated without delay. Since GPP was first described in 1910 by Leopold von Zumbusch, it has been inconsistently defined, stratified, and diagnosed in the literature. Multiple definitions and diagnostic criteria have been proposed over the years. Recently, formal consensus guidelines on GPP have been published by international groups. This article reviews the current evidence and understanding in the diagnosis and screening of GPP.

Neutrophilic Dermatoses and Their Implication in Pathophysiology of Asthma and Other Respiratory Comorbidities: A Narrative Review

Neutrophilic dermatoses (ND) are a polymorphous group of noncontagious dermatological disorders that share the common histological feature of a sterile cutaneous infiltration of mature neutrophils. Clinical manifestations can vary from nodules, pustules, and bulla to erosions and ulcerations. The etiopathogenesis of neutrophilic dermatoses has continuously evolved. Accumulating genetic, clinical, and histological evidence point to NDs being classified in the spectrum of autoinflammatory conditions. However, unlike the monogenic autoinflammatory syndromes where a clear multiple change in the inflammasome structure/function is demonstrated, NDs display several proinflammatory abnormalities, mainly driven by IL-1, IL-17, and tumor necrosis factor-alpha (TNF-a). Additionally, because of the frequent association with extracutaneous manifestations where neutrophils seem to play a crucial role, it was plausible also to consider NDs as a cutaneous presentation of a systemic neutrophilic condition. Neutrophilic dermatoses are more frequently recognized in association with respiratory disorders than by chance alone. The combination of the two, particularly in the context of their overlapping immune responses mediated primarily by neutrophils, raises the likelihood of a common neutrophilic systemic disease or an aberrant innate immunity disorder. Associated respiratory conditions can serve as a trigger or may develop or be exacerbated secondary to the uncontrolled skin disorder. Physicians should be aware of the possible pulmonary comorbidities and apply this knowledge in the three steps of patients' management, work-up, diagnosis, and treatment. In this review, we attempt to unravel the pathophysiological mechanisms of this association and also present some evidence for the role of targeted therapy in the treatment of both conditions.

Pustular Palmoplantar Psoriasis Successfully Treated with Nb-UVB Monochromatic Excimer Light: A Case-Report

Barber’s palmoplantar pustulosis (PPP) is a form of localised pustular psoriasis, affecting the palmar and plantar surfaces. It is a chronic disease, with a deep impact on the patients’ quality of life. The Authors discuss a case of Baber Psoriasis successfully treated with monochromatic excimer light.

Efficacy of the combined therapy with etanercept and methotrexat at the female patient with generalized pustular psoriasis and arthritis psoriasis after the therapeutic failure of two the TNF-α receptor inhibitors. Case study

The article presents the clinical observation effectiveness of TNF-a inhibitor etanercept in patients with generalized pustular psoriasis and PsA, resistant to treatment by other drugs of this class. It presents the current recommendations for the management of patients with pustular psoriasis.