Generalized pustular psoriasis patient with a heterozygous hypomorphic MPO variant refractory to intravenous spesolimab.

Generalized pustular psoriasis (GPP) is a recurrent and sometimes life-threatening sterile pustular disease. Because interleukin (IL)-36 is the central cytokine in disease formation, spesolimab, which interferes with IL-36 receptor signaling, is highly effective. Here, we report a patient with GPP with a heterozygous hypomorphic MPO variant refractory to intravenous spesolimab. Although spesolimab showed excellent clinical efficacy in resolving pre-existing pustules and erythema, it did not suppress the emergence of new pustules and erythema, which did not decrease the peripheral blood neutrophil count, therefore bimekizumab, an anti-IL-17A/IL-17F antibody, was administered after the second spesolimab infusion, which resolved the pustules and erythema. We discuss the possible reasons for the resistance mechanism to spesolimab.

Effective Management of Life-Threatening Generalized Pustular Psoriasis Flare With Spesolimab.

Generalized pustular psoriasis (GPP) presents as a severe variant of psoriasis featuring painful, sterile pustules on red skin and can lead to life-threatening complications if left untreated. The disease course is typically unpredictable, with periods of improvement, followed by relapses over extended periods. Managing GPP flares is challenging due to their potential to endanger the patient's life, underscoring the need for treatments that are both fast-acting and highly effective in the case of severe and systematically ill GPP patients. We present a case of a 48-year-old man with an extensive and severe GPP flare (GPP Physician Global Assessment score = 4), experiencing an extensive pustular rash on an erythematous base, intense skin exfoliation, and inflammation as well as systemic symptoms such as fever, hypotension, and general weakness. During the disease course, he developed comorbidities such as depression occurrence and an episode of an acute pulmonary embolism. Initial treatment attempts with acitretin and anakinra were not proved successful. Due to IL-36's significant role in GPP pathophysiology, the patient received treatment involving an IL-36 receptor antagonist (two infusions of 900 mg spesolimab administered one week apart), alongside continued acitretin therapy. This approach led to swift improvement, resolving pustules and skin inflammation and resulting in the patient's gradual recovery. This case highlights spesolimab's potential as a targeted therapy for severe GPP flares resistant to conventional treatments. However, further research is needed to establish its long-term safety and efficacy in managing GPP and related IL-36-mediated diseases.

Spesolimab for generalized pustular psoriasis: a review of two key clinical trials supporting initial US regulatory approval.

Generalized pustular psoriasis (GPP) is a chronic, rare, and potentially life-threatening inflammatory disease, characterized by the rapid and widespread eruption of small, sterile pustules with surrounding skin erythema. Abnormal signaling of the interleukin-36 (IL-36) pathway appears to have a central role in GPP immunopathology, and provides a rational therapeutic target. Spesolimab is a first-in-class humanized monoclonal antibody that binds specifically to the IL-36 receptor, and antagonizes IL-36 signaling. Spesolimab obtained regulatory approval in the United States (US) in September 2022 for use in the treatment of GPP flares in adults, and was subsequently approved for GPP flare treatment in many other countries across the world. Recently, regulatory approval was granted for subcutaneous dosing of spesolimab for treatment of GPP when not experiencing a flare. Here, we review data from two key clinical trials that supported the initial US regulatory approval; namely, the phase 1 proof-of-concept trial (ClinicalTrials.gov ID, NCT02978690), and Effisayil™ 1 (NCT03782792), which remains the largest and only randomized clinical trial in patients experiencing GPP flares published to date. In the phase 1 proof-of-concept trial, a Generalized Pustular Psoriasis Physician Global Assessment (GPPGA) score of 0 or 1 (clear or almost clear skin) was attained in 5/7 (71%) patients by week 1 and in all 7 patients by week 4; and the mean percent improvement in the Generalized Pustular Psoriasis Area and Severity Index (GPPASI) score from baseline was 59.0% at week 1, 73.2% at week 2, and 79.8% at week 4. In Effisayil™ 1, a GPPGA pustulation subscore of 0 (no visible pustules) was achieved in 19/35 (54%) patients receiving spesolimab at the end of week 1, versus 1/18 (6%) receiving placebo (difference, 49 percentage points; 95% confidence interval [CI], 21 to 67; P<0.001); and a GPPGA total score of 0 or 1 was achieved by 15/35 (43%) patients in the spesolimab group, versus 2/18 (11%) patients in the placebo group (difference, 32 percentage points; 95% CI, 2 to 53; P = 0.02). Infections at week 1 were reported in 6/35 (17%) patients receiving spesolimab and in 1/18 (6%) patients receiving placebo. These data demonstrate the efficacy and safety of spesolimab in providing rapid and sustained clinical improvement for patients with GPP flares, which translates into improved quality of life, by offering a targeted therapy for GPP.

RNA-binding proteins potentially regulate alternative splicing of immune/inflammatory-associated genes during the progression of generalized pustular psoriasis.

Generalized pustular psoriasis (GPP) is a rare but severe form of psoriasis. However, the pathogenesis of GPP has not been fully elucidated. Although RNA-binding proteins (RBPs) and the alternative splicing (AS) process are essential for regulating post-transcriptional gene expression, their roles in GPP are still unclear. We aimed to elucidate the regulatory mechanisms to identify potential new therapeutic targets. Here, We analyzed an RNA sequencing (RNA-seq) dataset (GSE200977) of peripheral blood mononuclear cells (PBMCs) of 24 patients with GPP, psoriasis vulgaris (PV), and healthy controls (HCs) from the Gene Expression Omnibus (GEO) database. We found that the abnormal alternative splicing (AS) events associated with GPP were mainly "alt3p/alt5p", and 15 AS genes were differentially expressed. Notably, the proportions of different immune cell types were correlated with the expression levels of regulatory alternatively spliced genes (RASGs): significant differences were observed in expression levels of DTD2, NDUFAF3, NBPF15, and FBLN7 in B cells and ARFIP1, IPO11, and RP11-326L24.9 in neutrophils in the GPP samples. Furthermore, We identified 32 differentially expressed RNA-binding proteins (RBPs) (18 up-regulated and 14 down-regulated). Co-expression networks between 14 pairs of differentially expressed RBPs and RASGs were subsequently constructed, demonstrating that these differentially expressed RBPs may affect the progression of GPP by regulating the AS of downstream immune/inflammatory-related genes such as LINC00989, ENC1 and MMP25-AS1. Our results were innovative in revealing the involvement of inflammation-related RBPs and RASGs in the development of GPP from the perspective of RBP-regulated AS.

Paradoxical Eczema Associated With Interleukin-17A Inhibitor Use in a Patient With Generalized Pustular Psoriasis Accompanied by Asthma.

Although rare, paradoxical eczema (PE) is an adverse event associated with the use of biological agents to treat psoriasis, particularly in patients with atopic predispositions. We report the first case of severe PE induced by secukinumab in a patient with generalized pustular psoriasis (GPP) and asthma. A woman in her 50s with a history of interstitial nephritis attributable to Sjogren's syndrome experienced a flare-up of GPP after discontinuing mycophenolate mofetil and was hospitalized. Treatment with secukinumab accompanied by an increased prednisolone level afforded rapid improvement, but she subsequently developed widespread, itchy, serous papules and erythema. A biopsy confirmed that the erythema was an eczematous reaction, thus PE. Her condition improved after switching from secukinumab to deucravacitinib with a temporary increase in the prednisolone level; no recurrence of GPP or PE was observed for 11 months. Elevated serum levels of interleukin (IL)-17A, IL-22, and the Th2 chemokine TARC recorded at the onset time of PE suggested that these mediators contributed to the observed pathology. Our case highlights the need for careful consideration when prescribing IL-17 inhibitors to patients with GPP, particularly those with atopic predispositions, given the potential activation of the Th2 axis and thus severe eczematous reactions. Further research is required to understand the essential nature of PE in patients with GPP and the roles of IL-17A and IL-22 in this context.

Clinical efficacy and safety of secukinumab in the treatment of generalized pustular psoriasis in the pediatric population: a systematic review of the literature.

Background: Generalized pustular psoriasis (GPP) is a severe type of psoriasis. The current treatment primarily relies on corticosteroids and immunosuppressants. In recent years, biologics have been increasingly utilized in the treatment of this disease, and have demonstrated good clinical efficacy. However, children and adolescents are primarily treated with immunosuppressants, which have limited clinical application due to the serious side effects they may cause. At the same time, the effectiveness of current treatments is unsatisfactory. Secukinumab has been widely reported to be effective and safe in treating this disease. However, there are still insufficient data on its use in treating GPP in children. Objective: To conduct a systematic review of the existing literature on the use of secukinumab for treating generalized pustular psoriasis in children and adolescents, and to evaluate its clinical effectiveness and safety. Methods: We conducted a systematic review of all the literature reporting on the treatment of GPP in children and adolescents with secukinumab. Results: A total of 7 papers (46 patients) were included in this study. After 12 weeks of treatment, all 46 participants were able to achieve a GPPASI score of 90 or higher, with approximately 96% of patients achieving complete clearing of the lesions (GPPASI 100 or JDA0). Adverse events were reported in 8 patients, the rate of adverse reactions was approximately 17%. Conclusion: The treatment of GPP in children and adolescents with secukinumab has a rapid onset of action and a high safety profile. However, the results of the literature may be influenced by publication bias.

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.

Generalized pustular psoriasis (GPP) is a rare, chronic skin condition characterized by painful, sterile pustules that can occur all over the body. These pustules may also be accompanied by systemic inflammation, which can lead to serious health complications. GPP significantly impacts patients' quality of life and can even be life-threatening. Because the disease is so rare, treatment guidelines have typically been based on those for plaque psoriasis. However, these guidelines do not specifically address the unique needs of GPP. In this review, we analysed the published literature on GPP management, focussing on treatment efficacy, safety and quality of life outcomes. We searched the literature databases Embase and MEDLINE for articles published between 1980 and September 2023. In total, we identified 118 publications on this topic, covering a wide range of therapies; only one of these therapies, spesolimab, reported results from placebo-controlled randomized trials. Based on these trials, spesolimab is now approved for GPP treatment in the USA, Japan, China, the EU and several other countries. Some other therapies are approved exclusively in Japan and Taiwan based on small, open-label studies in the absence of higher-quality data. To date, comparing treatments has been challenging because of different clinical outcomes used to measure effectiveness. However, well-defined endpoints specific to GPP have recently been developed and used in trials. In conclusion, our review highlights the need for prospective randomized studies with GPP-specific endpoints to determine the best treatment strategy.

Spesolimab Reduces Inflammation in Generalized Pustular Psoriasis: Molecular Characterization of Flare Treatment in EFFISAYIL 1.

EFFISAYIL 1 was a randomized, placebo-controlled study of spesolimab, an anti-IL-36 receptor antibody, in patients presenting with a generalized pustular psoriasis flare. Treatment with spesolimab led to more rapid pustular and skin clearance versus treatment with placebo in approximately half of the patients. In this study, we present histologic, transcriptomic, and proteomic analyses of lesional and nonlesional skin and whole-blood samples collected from EFFISAYIL 1. Treatment with spesolimab led to a transition toward a nonlesional profile, with a downregulation of gene expressions in the skin of IL-36 transcripts (IL36α, IL36ß, IL36γ) and those associated with neutrophil recruitment (CXCL1, CXCL6, CXCL8), proinflammatory cytokines (IL6, IL19, IL20), and skin inflammation (DEFB4A, S100A7, S100A8). Changes were manifest at week 1 and sustained to week 8. At the systemic level, reductions in serum biomarkers of inflammation (IL-17, IL-8, IL-6) were sustained until 12 weeks after spesolimab treatment. Considerable overlap was observed in the spesolimab-induced changes in gene and protein expressions from skin and blood samples, demonstrating the molecular basis of the effects of spesolimab on controlling local and systemic inflammation. Data are consistent with the mode of action of spesolimab, whereby inhibition of the IL-36 pathway leads to subsequent reductions in the key local and systemic pathologic events associated with generalized pustular psoriasis flares.

[Translated article] Improvements in the Management of Patients With Generalized Pustular Psoriasis in Spain: Recommendations From a Group of Experts.

This consensus document analyzed the management and emotional journey of patients with GPP (generalized pustular psoriasis), and the desirable course of the disease while detecting critical points and translating them into needs and recommendations. This project was conducted in 3 phases with participation from an advisory committee (n=8), an expert panel (n=15) and patients with GPP (n=6). The patients' disease progression was heterogeneous due to disease variations, different health care models implemented and available resources, and the lack of diagnostic and treatment guidelines. A total of 45 different recommendations have been made to optimize management and address the emotional component of these patients. Five of them stand out for their impact and viability. Therefore, a roadmap of priorities has been made generally available to improve the management of patients with GPP.

Clinical Characteristics and Disease Burden of Patients with Moderate-to-Severe Generalized Pustular Psoriasis Flares in Taiwan.

INTRODUCTION: Generalized pustular psoriasis (GPP) is a rare and severe psoriasis subtype characterized by the rapid onset of coalescing sterile pustules over broad body areas and systemic inflammation. Data on its clinical course and outcomes in Taiwan are limited. We evaluated the clinical profile and outcomes of patients with GPP flares in Taiwan. METHODS: This retrospective analysis included adult patients with moderate-to-severe GPP flares occurring in January 2008-December 2021. Data were extracted from medical charts and electronic health records in the Chang Gung Research Database. Statistical analyses were performed using SAS for Windows (version 9.4). Multivariate Poisson regression models were built to investigate different predictors of GPP flare rate. RESULTS: Thirty-four patients with 81 moderate-to-severe GPP flares were identified. Of the 14 patients undergoing genetic analysis, 10 (71.4%) had an IL36RN mutation. Patients' mean age at the index GPP flare was 47.1 ± 16.5 years; 58.0% of the flares were severe, while 42.0% were moderate. Overall, 96.3% of GPP flares were treated with at least one systemic therapy, acitretin being the most prescribed (85.2%), followed by cyclosporine (45.7%) and methotrexate (18.5%). After treatment, the proportion of flares responding positively increased from 0% on day 2 to 6.2% by week 12. Patients were newly diagnosed with psoriasis (23.5%), hypertension (20.6%), diabetes mellitus (14.7%), psoriatic arthritis (2.9%), malignant tumor (8.8%), and depression/anxiety (2.9%) after enrollment. Complications occurring within 12 weeks of GPP flares included arthritis (25.9% of the flares), skin infection (8.6%), and other infections (2.5%). No fatalities were reported. In the multivariate model, former smokers, patients with hepatic disease, and patients with psoriatic arthritis had an increased GPP rate ratio (RR) of 13.33 (95% confidence interval, CI, 2.87-61.78), 14.08 (95% CI 3.04-65.29), and 34.84 (95% CI 4.77- 254.42), respectively. Contrarily, obese and rheumatoid arthritis patients had a lower GPP rate ratio of 0.21 (95% CI 0.08-0.54) and 0.07 (95% CI 0.006-0.78), respectively. CONCLUSIONS: Our findings highlight the complexity of GPP flare presentations and the need for individualized, patient-centered management approaches and continued research to improve affected individuals' care and outcomes.

A Non-Interventional, Multicenter Study to Characterize the Socio-Demographics, Clinical Characteristics, and Management of Generalized Pustular Psoriasis Patients in Spain: IMPULSE Study.

INTRODUCTION: Generalized pustular psoriasis (GPP) is a chronic, rare, and potentially life-threatening skin condition characterized by flares comprising widespread sterile pustules and systemic inflammation. Both the rarity and heterogeneity of the disease have made GPP classification and standardization of clinical criteria challenging. Before the approval of spesolimab (IL-36R antibody) in 2022, there were no approved treatments in the USA or Europe for GPP flares. Treatment for GPP has amounted to off-label use of medicines approved to treat plaque psoriasis. Our aim was to describe the sociodemographics, clinical characteristics, and treatment patterns of patients with GPP in Spain. METHODS: Non-interventional, descriptive, multi-center, retrospective chart review of patients diagnosed with GPP in Spain. RESULTS: 56 patients (50% women) were included, with a mean (standard deviation, SD) age at diagnosis of 53.7 (20.5) and a mean (SD) time of follow-up of 3.7 (3.1) years. In 80% of patients, GPP diagnosis was associated with a flare and 67.3% had known risk factors for GPP (such as previous diagnosis or family history of plaque psoriasis, comorbidities, smoking or stress). Hypertension and plaque psoriasis were the most frequent comorbidities (44.6% each). The number of GPP flares per patient-year was 0.55 with (range 0-4) a mean (SD) body surface area involvement of 21.3% (19.1). The most frequent manifestations of GPP flares were pustules (88.5%), erythema (76.9%), and scaling (76.9%). Additionally, 65.4% of patients had plaque psoriasis, 53.8% had unspecified skin lesions, and 30.8% experienced pain. The treatments used for GPP flares were off-label conventional systemic drugs (75%), mostly corticosteroids, cyclosporine, and acitretin. In the periods between flares, off-label biologics were used in 56.5% of patients. During the study period, 9 patients (16.1%) had at least one complication and 5 of them required hospitalization. CONCLUSION: This is the first multicenter study in Spanish GPP patients. Most patients were in their fifties, with personal or family history of plaque psoriasis, stress, smoking and a wide range of comorbidities and complications. Even though the number of flares per patient/year was 0.55, there was variability between patients. Both off-label conventional systemics and off-label biologics were used for flare management without a clear treatment pattern.

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.

Pharmacokinetics and Safety of Spesolimab in Healthy Chinese Subjects: An Open-Label, Phase I Study.

INTRODUCTION: Generalized pustular psoriasis (GPP) is a rare and potentially life-threatening inflammatory skin disease. Interleukin (IL)-36 signalling may play a central role in GPP pathogenesis. Spesolimab is a humanized anti-IL-36 monoclonal antibody inhibiting the IL-36 signalling pathway. Here, we investigated the pharmacokinetics and safety of spesolimab in healthy Chinese subjects. METHODS: In this Phase 1, single-dose, parallel-group, open-label study, healthy Chinese subjects aged 18-45 years received a single spesolimab dose by intravenous infusion (IV; 450 mg, 900 mg, or 1200 mg) or subcutaneous (SC) administration (300 mg or 600 mg). Primary endpoints were spesolimab exposure (area under the plasma concentration-time curve and maximum plasma concentration); secondary endpoints were treatment-emergent adverse events (TEAEs) and drug-related adverse events (AEs). RESULTS: Fifty subjects received IV (n = 30) or SC (n = 20) spesolimab (n = 10 per dose group); 60.0% were male, mean ± standard deviation age was 31.5 ± 6.6 and 31.0 ± 6.5 years in the IV and SC groups, respectively. Spesolimab exposure increased in a dose-proportional manner in both groups. TEAEs were reported in 83.3% and 80.0% of subjects in the IV and SC groups, the most common TEAE was upper respiratory tract infection (20.0% and 25.0%, respectively). One serious AE of hand fracture was reported in the 900 mg IV group that was not considered drug-related. Drug-related AEs were reported in 53.3% and 55.0% of subjects in the IV and SC groups. All laboratory-related AEs were mild and resolved. CONCLUSION: Spesolimab exposure increased in a dose-proportional manner after a single dose by IV and SC administration. Spesolimab was well tolerated in healthy Chinese subjects. CLINICAL TRIAL REGISTRATION: Clinicaltrials.gov registration: NCT04390568.

Generalized Pustular Psoriasis of Pregnancy Successfully Treated With Certolizumab Pegol: A Case Report and Literature Review.

Generalized pustular psoriasis of pregnancy (GPPP) is a rare dermatological condition that significantly affects maternal health and pregnancy outcomes. The treatment of this disease might be very challenging, as only a limited number of effective therapeutic options are available. If the use of systemic drugs is considered, they should ideally effectively control the systemic inflammation without harming the fetus. Here, we report the successful treatment of a severe case of GPPP in a 28-year-old woman using the tumor necrosis factor-alpha inhibitor (TNFi) certolizumab pegol. Additionally, we review the existing literature on the use of this class of drugs for treating GPPP. To date, there are only 11 reported cases of this severe skin condition treated with a TNFi. We also discuss the pathogenesis of GPPP and the rationale behind using TNFi for its treatment.

Generalized Pustular Psoriasis and Systemic Organ Dysfunctions.

This review explores the intricate relationship between generalized pustular psoriasis (GPP) and various systemic diseases, shedding light on the broader impacts of this severe skin condition beyond its primary dermatological manifestations. GPP is identified as not only a profound contributor to skin pathology but also a significant risk factor for systemic diseases affecting cardiovascular, hepatic, renal, pulmonary, and skeletal systems, as well as associated with an increased incidence of anemia, depression, anxiety, and arthritis. The research highlights the complex interplay of cytokines, particularly IL-17 and IL-36, which are central to the pathophysiology of GPP and implicated in the exacerbation of systemic conditions. Key findings indicate a higher incidence of cardiovascular events in GPP patients compared to those with other severe forms of psoriasis, notably with a stronger correlation between myocardial infarction history and GPP development. Liver disturbances, frequently reversible upon psoriasis remission, suggest a cytokine-mediated link to hepatic health. Renal dysfunction appears elevated in GPP sufferers, with IL-17 and IL-36 potentially driving renal fibrosis. Similarly, interstitial lung disease and osteoporosis in GPP patients underscore the systemic reach of inflammatory processes initiated in the skin. The associations with anemia, depression, anxiety, and arthritis further complicate the clinical management of GPP, requiring a multidisciplinary approach. The study concludes that managing GPP effectively requires a holistic approach that addresses both the cutaneous and systemic dimensions of the disease, advocating for continued research into the mechanisms that connect GPP with broader health implications to refine therapeutic strategies.

Spesolimab in the Management of Generalized Pustular Psoriasis With Concurrent Bullous Pemphigoid and Psoriasis.

Autoimmune diseases often co-occur due to shared immunological mechanisms, necessitating strategic treatment approaches to manage overlapping conditions without exacerbating each other. A 75-year-old male with a history of psoriasis vulgaris and bullous pemphigoid (BP) developed new-onset pustular psoriasis under systemic corticosteroid therapy, which is known to potentially worsen psoriasis into its pustular form. Histological examination confirmed the diagnosis, showing features typical of pustular psoriasis. The patient was successfully treated with spesolimab, an anti-IL-36 neutralizing antibody, achieving complete remission without aggravating the BP. This case highlights the necessity of cautious treatment selection in patients with multiple autoimmune disorders and underscores the potential role of IL-36 in exacerbating inflammatory responses in BP. Further research into the interaction between IL-36 and BP may provide deeper insights into managing such complex clinical scenarios.