Estimating the burden of vitiligo: a systematic review and modelling study.

BACKGROUND: Vitiligo is a chronic autoimmune disease characterised by depigmented skin patches, which can pose substantial psychosocial challenges particularly in individuals with dark skin tones. Despite its impact on quality of life, there is an absence of standardised global epidemiological data. We sought to address this gap with the present study. METHODS: In this study we did a systematic review and modelling analysis to estimate the global, regional, and national prevalence and incidence of vitiligo. We did a comprehensive search of nine digital libraries (PubMed, Embase, Web of Science, Scientific Electronic Library Online, KCI Korean Journal Database, Russian Science Citation Index, Western Pacific Region Index Medicus, Informit, and Health Research and Development Information Network) from inception up to May 25, 2023. We included cross-sectional or cohort studies reporting the incidence rate or prevalence of vitiligo, or data from which incidence rate or prevalence could be calculated, in the general population of a country or area of a country. Summary estimate data were extracted. A main outcome was to estimate the worldwide, regional, and country-specific lifetime prevalence of vitiligo diagnosed by physicians or dermatologists among the general population and in adults and children (as per age groups defined in included studies). We used a Bayesian hierarchical linear mixed model to estimate prevalence, and calculated number of affected individuals using the UN population structure in 2022. In estimating lifetime prevalence, studies reporting point or period prevalence were excluded. Our other main outcome was to estimate incidence rates of vitiligo, but due to a small number of studies, the data on incidence were presented in a descriptive summary. This study was registered on PROSPERO, CRD42023390433. FINDINGS: Our search identified 22 192 records, of which 90 studies met our inclusion criteria. Of these studies, six focused on the incidence of vitiligo, 79 reported on the prevalence of vitiligo, and five provided data on both incidence and prevalence. 71 studies reported on lifetime prevalence. In the most recent years studied, incidence rates in the general population ranged from 24·7 cases (95% CI 24·3-25·2) per 100 000 person-years in South Korea in 2019, to 61·0 cases (60·6-61·4) in the USA in 2017. In individual studies, incidence rates showed an increasing trend over the periods studied. The global lifetime prevalence of vitiligo diagnosed by a physician or dermatologist was estimated at 0·36% (95% credible interval [CrI] 0·24-0·54) in the general population (28·5 million people [95% CrI 18·9-42·6]), 0·67% (0·43-1·07) in the adult population (37·1 million adults [23·9-58·9]), and 0·24% (0·16-0·37) in the child population (5·8 million children [3·8-8·9]). Vitiligo prevalence was higher in adults than in children across all regions. Central Europe and south Asia reported the highest prevalence (0·52% [0·28-1·07] and 0·52% [0·33-0·82], respectively, in the general population). INTERPRETATION: This study highlights the need for standardised epidemiological data collection globally to inform public health policies and improve vitiligo diagnosis and management. Emphasis on the impact on individuals with darker skin tones is crucial to reducing stigma and improving quality of life. Furthermore, our study highlights the need to conduct more research in regions and populations that have been historically under-represented, to effectively address the worldwide burden of vitiligo. FUNDING: None.

Tree-Based Machine Learning to Identify Predictors of Psoriasis Incidence at the Neighborhood Level: A Populational Study from Quebec, Canada.

BACKGROUND: Psoriasis is a major global health burden affecting ~ 60 million people worldwide. Existing studies on psoriasis focused on individual-level health behaviors (e.g. diet, alcohol consumption, smoking, exercise) and characteristics as drivers of psoriasis risk. However, it is increasingly recognized that health behavior arises in the context of larger social, cultural, economic and environmental determinants of health. We aimed to identify the top risk factors that significantly impact the incidence of psoriasis at the neighborhood level using populational data from the province of Quebec (Canada) and advanced tree-based machine learning (ML) techniques. METHODS: Adult psoriasis patients were identified using International Classification of Disease (ICD)-9/10 codes from Quebec (Canada) populational databases for years 1997-2015. Data on environmental and socioeconomic factors 1 year prior to psoriasis onset were obtained from the Canadian Urban Environment Health Consortium (CANUE) and Statistics Canada (StatCan) and were input as predictors into the gradient boosting ML. Model performance was evaluated using the area under the curve (AUC). Parsimonious models and partial dependence plots were determined to assess directionality of the relationship. RESULTS: The incidence of psoriasis varied geographically from 1.6 to 325.6/100,000 person-years in Quebec. The parsimonious model (top 9 predictors) had an AUC of 0.77 to predict high psoriasis incidence. Amongst top predictors, ultraviolet (UV) radiation, maximum daily temperature, proportion of females, soil moisture, urbanization, and distance to expressways had a negative association with psoriasis incidence. Nighttime light brightness had a positive association, whereas social and material deprivation indices suggested a higher psoriasis incidence in the middle socioeconomic class neighborhoods. CONCLUSION: This is the first study to highlight highly variable psoriasis incidence rates on a jurisdictional level and suggests that living environment, notably climate, vegetation, urbanization and neighborhood socioeconomic characteristics may have an association with psoriasis incidence.

Risk of Paradoxical Eczema in Patients Receiving Biologics for Psoriasis.

Importance: Biologics used for plaque psoriasis have been reported to be associated with an atopic dermatitis (AD) phenotype, or paradoxical eczema, in some patients. The risk factors for this are unknown. Objective: To explore risk of paradoxical eczema by biologic class and identify factors associated with paradoxical eczema. Design, Setting, and Participants: This prospective cohort study used data from the British Association of Dermatologists Biologics and Immunomodulators Register for adults treated with biologics for plaque psoriasis who were seen at multicenter dermatology clinics in the UK and Ireland. Included participants were registered and had 1 or more follow-up visits between September 2007 and December 2022. Exposures: Duration of exposure to tumor necrosis factor (TNF) inhibitors, interleukin (IL) 17 inhibitors, IL-12/23 inhibitors, or IL-23 inhibitors until paradoxical eczema onset, treatment discontinuation, last follow-up, or death. Main Outcomes and Measures: Incidence rates of paradoxical eczema, paradoxical eczema risk by biologic class, and the association of demographic and clinical variables with risk of paradoxical eczema were assessed using propensity score-weighted Cox proportional hazards regression models. Results: Of 56 553 drug exposures considered, 24 997 from 13 699 participants were included. The 24 997 included exposures (median age, 46 years [IQR, 36-55 years]; 57% male) accrued a total exposure time of 81 441 patient-years. A total of 273 exposures (1%) were associated with paradoxical eczema. The adjusted incidence rates were 1.22 per 100 000 person-years for IL-17 inhibitors, 0.94 per 100 000 person-years for TNF inhibitors, 0.80 per 100 000 person-years for IL-12/23 inhibitors, and 0.56 per 100 000 person-years for IL-23 inhibitors. Compared with TNF inhibitors, IL-23 inhibitors were associated with a lower risk of paradoxical eczema (hazard ratio [HR], 0.39; 95% CI, 0.19-0.81), and there was no association of IL-17 inhibitors (HR, 1.03; 95% CI, 0.74-1.42) or IL-12/23 inhibitors (HR, 0.87; 95% CI, 0.66-1.16) with risk of paradoxical eczema. Increasing age (HR, 1.02 per year; 95% CI, 1.01-1.03) and history of AD (HR, 12.40; 95% CI, 6.97-22.06) or hay fever (HR, 3.78; 95% CI, 1.49-9.53) were associated with higher risk of paradoxical eczema. There was a lower risk in males (HR, 0.60; 95% CI, 0.45-0.78). Conclusions and Relevance: In this study, in biologic-treated patients with psoriasis, paradoxical eczema risk was lowest in patients receiving IL-23 inhibitors. Increasing age, female sex, and history of AD or hay fever were associated with higher risk of paradoxical eczema. The overall incidence of paradoxical eczema was low. Further study is needed to replicate these findings.

Cross-Comparison of Inflammatory Skin Disease Transcriptomics Identifies PTEN as a Pathogenic Disease Classifier in Cutaneous Lupus Erythematosus.

Tissue transcriptomics is used to uncover molecular dysregulations underlying diseases. However, the majority of transcriptomics studies focus on single diseases with limited relevance for understanding the molecular relationship between diseases or for identifying disease-specific markers. In this study, we used a normalization approach to compare gene expression across nine inflammatory skin diseases. The normalized datasets were found to retain differential expression signals that allowed unsupervised disease clustering and identification of disease-specific gene signatures. Using the NS-Forest algorithm, we identified a minimal set of biomarkers and validated their use as diagnostic disease classifier. Among them, PTEN was identified as being a specific marker for cutaneous lupus erythematosus and found to be strongly expressed by lesional keratinocytes in association with pathogenic type I IFNs. In fact, PTEN facilitated the expression of IFN-ß and IFN-κ in keratinocytes by promoting activation and nuclear translocation of IRF3. Thus, cross-comparison of tissue transcriptomics is a valid strategy to establish a molecular disease classification and to identify pathogenic disease biomarkers.

Risk of serious infection and infection mortality in patients with psoriasis: A nationwide cohort study using the Taiwan National Health Insurance claims database.

BACKGROUND: The risks of serious infections that lead to hospitalization and mortality in patients with psoriasis in Asia have not been comprehensively studied. OBJECTIVES: We examined the incidence of serious infection and infection mortality in patients with psoriasis. METHODS: This population-based retrospective cohort study used the Taiwan National Health Insurance claims database from 2000 to 2017. Adult patients with psoriasis were identified by a relevant International Classification of Diseases (ICD) code and matched to six comparators without psoriasis on age and sex. Psoriasis patients were categorized as having moderate-to-severe disease once exposed to systemic therapies, phototherapy or biologic therapies. The incidence of serious infection and infection mortality were identified by ICD codes from inpatient hospitalization and death registration. Cox proportional hazard models were used to compare the risk, and the results were adjusted for covariates and presented as adjusted hazard ratios (aHR) and 95% confidence interval (95% CI). RESULTS: Overall, 185,434 psoriasis patients and 1,112,581 comparators were included. A higher rate of serious infection (aHR: 1.21, 95% CI: 1.19-1.22) was found in patients with psoriasis compared to matched comparators without psoriasis, and the risk was enhanced when patients had moderate-to-severe psoriasis (aHR: 1.30, 95% CI: 1.27-1.34). Specifically, there was an increased risk of serious infection due to respiratory infections (aHR: 1.11, 95% CI: 1.09-1.13), skin/soft-tissue infections (aHR: 1.57, 95% CI: 1.52-1.62), sepsis (aHR: 1.23, 95% CI: 1.19-1.27), urinary tract infections (aHR: 1.11, 95% CI: 1.08-1.14), hepatitis B (aHR: 1.18, 95% CI: 1.06-1.30) and hepatitis C (aHR: 1.49, 95% CI: 1.32-1.69). Furthermore, psoriasis patients were associated with a higher risk of infection-related mortality (aHR: 1.15, 95% CI: 1.11-1.18) compared to matched comparators. CONCLUSION: Patients with psoriasis had a higher risk of serious infection and infection mortality, which was enhanced by moderate-to-severe psoriasis. Practitioners should be aware of the increased risk in patients with psoriasis, but it should not be a barrier to offering effective treatment.

Implementing well-being in the management of psoriasis: An expert recommendation.

Psoriasis causes detriment in a person's physical, mental and social health which impairs their quality of life (QoL). However, the current psoriasis management may not adequately address all relevant health domains. Since the goal of healthcare is to restore or maintain health, health outcomes should include all areas of the patient's overall health. Life satisfaction, QoL and patient well-being are essential to a comprehensive approach to the disease. With the inclusion of more people-centred policies, care of patients with psoriasis should evolve towards a holistic and integrated assessment of the disease impact, including subjective measures of well-being in order to encompass all aspects of health. The main objective of this expert review is to give the concept of well-being a place as an entity within the holistic therapeutic approach for patients with psoriasis. Identifying and defining common goals beyond the skin with the patient and testing them throughout the course of treatment will benefit and enhance treatment success. We propose a series of recommendations for application in clinical practice, providing tangible clinical guidance for implementing well-being in the management of psoriasis. Among the recommendations are the need to initially listen to the patient, to know their level of empowerment or what they want to achieve, their preferences in decision making, the evaluation of not only the physical but also the emotional impact of the disease (well-being), the definition of the aspects that can generate a cumulative deterioration of the disease throughout life, and a continuous assessment of the patient's preferences with the opinion of the expert clinician and the integration of the knowledge of external clinical evidence.

GWAS meta-analysis of psoriasis identifies new susceptibility alleles impacting disease mechanisms and therapeutic targets.

Psoriasis is a common, debilitating immune-mediated skin disease. Genetic studies have identified biological mechanisms of psoriasis risk, including those targeted by effective therapies. However, the genetic liability to psoriasis is not fully explained by variation at robustly identified risk loci. To move towards a saturation map of psoriasis susceptibility we meta-analysed 18 GWAS comprising 36,466 cases and 458,078 controls and identified 109 distinct psoriasis susceptibility loci, including 45 that have not been previously reported. These include susceptibility variants at loci in which the therapeutic targets IL17RA and AHR are encoded, and deleterious coding variants supporting potential new drug targets (including in STAP2, CPVL and POU2F3). We conducted a transcriptome-wide association study to identify regulatory effects of psoriasis susceptibility variants and cross-referenced these against single cell expression profiles in psoriasis-affected skin, highlighting roles for the transcriptional regulation of haematopoietic cell development and epigenetic modulation of interferon signalling in psoriasis pathobiology.

Human Mast Cells Upregulate Cathepsin B, a Novel Marker of Itch in Psoriasis.

Mast cells (MCs) contribute to skin inflammation. In psoriasis, the activation of cutaneous neuroimmune networks commonly leads to itch. To dissect the unique contribution of MCs to the cutaneous neuroinflammatory response in psoriasis, we examined their density, distribution, relation to nerve fibres and disease severity, and molecular signature by comparing RNA-seq analysis of MCs isolated from the skin of psoriasis patients and healthy volunteers. In involved psoriasis skin, MCs and Calcitonin Gene-Related Peptide (CGRP)-positive nerve fibres were spatially associated, and the increase of both MC and nerve fibre density correlated with disease severity. Gene set enrichment analysis of differentially expressed genes in involved psoriasis skin showed significant representation of neuron-related pathways (i.e., regulation of neuron projection along with dendrite and dendritic spine morphogenesis), indicating MC engagement in neuronal development and supporting the evidence of close MC-nerve fibre interaction. Furthermore, the analysis of 208 identified itch-associated genes revealed that CTSB, TLR4, and TACR1 were upregulated in MCs in involved skin. In both whole-skin published datasets and isolated MCs, CTSB was found to be a reliable indicator of the psoriasis condition. Furthermore, cathepsin B+ cells were increased in psoriasis skin and cathepsin B+ MC density correlated with disease severity. Therefore, our study provides evidence that cathepsin B could serve as a common indicator of the MC-dependent itch signature in psoriasis.

Behaviour and sun exposure in holidaymakers alters skin microbiota composition and diversity.

Introduction: The skin microbiota plays a crucial role in maintaining epidermal homeostasis. Ultraviolet radiation (UVR) and other environmental challenges can impact the skin microbiota through direct and indirect mechanisms. This study aimed to investigate the effects of sun exposure on the skin microbiota and its relationship with individual skin phototypes. Methods: Healthy volunteers (n = 21 [4M, 17 F], mean age 33.2 years) holidayed in a sunny destination for a minimum of 7 days with swabs taken pre-holiday and up to 84 days post-holiday. Participant group was categorised by individual typology angle (ITA) classification and the composition of the skin microbiota was examined using 16S rRNA gene sequencing. Results: In the entire cohort and at all time points, the major bacterial phyla were Actinobacteria, Proteobacteria and Firmicutes. There was a significant change in microbial beta diversity at day 28 post-holiday, compared to baseline, for all participants. However, when participants were segregated into three cohorts dependent on the degree of skin tanning response between baseline (pre-holiday) and immediately one-day post-holiday, there was a reduction in Proteobacteria in the sun-seeking participants 1 day after the holiday, which recovered over time. Discussion: These findings suggest that sun exposure can affect the diversity and composition of the skin microbiota, which may have downstream effects on skin health.

Integrated proteomics and genomics analysis of paradoxical eczema in psoriasis patients treated with biologics.

BACKGROUND: Few studies have explored the immunology and genetic risk of paradoxical eczema occurring as an adverse event of biologic therapy in patients with psoriasis. OBJECTIVES: We sought to describe the systemic inflammatory signature of paradoxical eczema using proteomics and explore whether this is genetically mediated. METHODS: This study used the Olink Target 96 Inflammation panel on 256 serum samples from 71 patients with psoriasis and paradoxical eczema, and 75 controls with psoriasis to identify differentially expressed proteins and enriched gene sets. Case samples from 1 or more time points (T1 prebiologic, T2 postbiologic, and T3 postparadoxical eczema) were matched 1:1 with control samples. Genes contributing to enriched gene sets were selected, and functional single nucleotide polymorphisms used to create polygenic risk scores in a genotyped cohort of 88 paradoxical eczema cases and 3124 psoriasis controls. RESULTS: STAMBP expression was lower in cases at T1 than in controls (log-fold change: -0.44; adjusted P = .022); no other proteins reached statistical significance at equivalent time points. Eleven gene sets including cytokine and chemokine pathways were enriched in cases at T2 and 10 at T3. Of the 39 proteins contributing to enriched gene sets, the majority are associated with the atopic dermatitis serum proteome. A polygenic risk score including 38 functional single nucleotide polymorphisms linked to enriched gene sets was associated with paradoxical eczema (adjusted P = .046). CONCLUSIONS: The paradoxical eczema systemic inflammatory proteome trends toward atopic dermatitis at a gene-set level and is detectable before onset of the phenotype. This signature could be genetically determined.

Fertility Trends and Adverse Pregnancy Outcomes in Female Patients With Psoriasis in the UK.

Importance: Evidence regarding fertility trends and obstetric outcomes among patients with psoriasis is limited by studies of small sample sizes, noninclusion of comparators, and the lack of accurate pregnancy records. Objective: To investigate fertility rates and obstetric outcomes of pregnancies in female patients with psoriasis compared with age- and general practice-matched comparators without psoriasis. Design, Setting, and Participants: This population-based cohort study used data from 887 primary care practices that contributed to the UK Clinical Practice Research Datalink GOLD database between 1998 and 2019, linked to a pregnancy register and Hospital Episode Statistics. There were 6 223 298 patients of common childbearing ages (15-44 years), and 63 681 patients with psoriasis had at least 1 year of follow-up data prior to the diagnosis of psoriasis. For each patient with psoriasis, 5 patients were matched by age from the same general practice. The median follow-up duration was 4.1 years. Data analysis was performed in 2021. Exposures: Patients with psoriasis were identified using clinical diagnostic codes from consultations. Main Outcomes and Measures: Fertility rates were calculated as the number of pregnancies per 100 patient-years. The outcomes of each pregnancy recorded in the pregnancy register or Hospital Episode Statistics were screened to identify obstetric outcomes. A negative binomial model was used to examine the association between psoriasis and the fertility rate. Logistic regression was applied to compare the association between psoriasis and obstetric outcomes. Results: A total of 63 681 patients with psoriasis and 318 405 matched comparators were included in the analysis (median [IQR] age, 30 [22-37] years). Lower fertility rates (rate ratio, 0.75; 95% CI, 0.69-0.83) were found in patients with moderate to severe psoriasis. Compared with matched comparators without psoriasis, pregnancies in patients with psoriasis had a higher risk of loss (odds ratio, 1.06; 95% CI, 1.03-1.10); however, there was no increase in the risks of antenatal hemorrhage, preeclampsia, or gestational diabetes. Conclusion and Relevance: In this cohort study, patients with moderate to severe psoriasis had a lower fertility rate, and the risk of pregnancy loss was higher than in matched comparators without psoriasis. Future research should identify the mechanism of increased risk of pregnancy loss among patients with psoriasis.

Incidence and prevalence of generalized pustular psoriasis in multiethnic Johor Bahru, Malaysia: a population-based cohort study using routinely captured electronic health records in the Teleprimary Care (TPC®) clinical information system from 2010 to 2020.

BACKGROUND: There is limited understanding of the epidemiology of generalized pustular psoriasis (GPP) internationally, with no population-based estimates of GPP in South East Asia. OBJECTIVES: To determine the incidence and prevalence of GPP in the Malaysian population and characterize its flares and trigger factors. METHODS: We conducted a population-based cohort study using the Teleprimary Care database between January 2010 and December 2020. We identified 230 dermatologist-confirmed GPP cases using International Classification of Diseases, 10th revision, diagnostic codes. Annual prevalence and incidence rates were stratified by age, sex and ethnicity. We compared data regarding flares and trigger factors for patients with GPP who had associated psoriasis vulgaris (PV) with those who did not have associated PV. RESULTS: The prevalence of GPP was 198 per million (267 women, 127 men) and incidence was 27.2 per million person-years [95% confidence interval (CI) 22.8-31.6]; 35.3 (28.4-42.2) per million person-years for women and 18.3 (13.1-23.5) per million person-years for men. Rates were higher in Chinese individuals [prevalence 271 per million; incidence 41.6 per million person-years (28.9-54.3)] than in the Malay population [prevalence 186; incidence 24.6 (19.4-29.7)] or the Indian ethnic group [prevalence 179; incidence 25.0 (13.8-36.3)]. Annual prevalence was consistently higher in women than in men and highest among the Chinese population, followed by the Indian and Malay populations. Overall, 67% of patients with GPP had associated PV. The prevalence and incidence of GPP without PV were lower than GPP with PV at 66 vs. 132 per million and 19.3 (95% CI 15.6-23.0) vs. 8.0 (95% CI 5.6-10.3) per million person-years, respectively. The mean age at GPP onset was 42.7 years (SD 18.4). A bimodal trend in the age of GPP onset was observed, with first and second peaks at age 20-29 years and age 50-59 years, respectively. Disease onset was significantly earlier in patients with GPP without PV than in those with PV [mean age 37.5 years (SD 20.7) vs. 44.9 years (SD 17.0), P = 0.026]. Flares occurred more frequently in patients without PV than in those with PV [mean number of flares per patient per year was 1.35 (SD 0.77) vs. 1.25 (SD 0.58), P = 0.039]. Common triggers of flares in patients with GPP who did not have PV were infections, pregnancy, menstruation and stress, whereas withdrawal of therapy, particularly systemic corticosteroids, was a more frequent trigger in patients with GPP who also had PV. CONCLUSIONS: Our findings contribute to the global mapping of GPP, which will help inform the management of this rare condition.

Improving skin health of community-dwelling older people: a scoping review protocol.

INTRODUCTION: Ageing is accompanied by an age-related decrease in mobility or cognitive and sensory functions; in addition, physiological changes in the skin occur with age. Therefore, the skin requires appropriate care and observation in order to prevent or manage a variety of dermatological diseases and conditions, and to prevent or minimise effects on the quality of life.Globally, most older people live at home, and the need to establish sustainable structures and processes to support and to care for people at home for as long as possible has been emphasised. The body of evidence supporting screening, diagnosis and management of skin conditions in older people living at home has not been collated and summarised to date. The aim of this scoping review is to describe and summarise the extent and nature of the available body of evidence in this regard. METHODS AND ANALYSIS: This scoping review will follow the Preferred Reporting Items for Systematic Reviews and Meta-Analyses extension for Scoping Reviews. Eligibility criteria were developed using the Population, Concept and Context framework, and the search will focus on systematic and scoping reviews as well as clinical practice guidelines. Two reviewers will conduct systematic searches, screen and select identified evidence as well as extract and chart data, independently. Finally, data will be systematically analysed and summarised descriptively to map existing evidence and identify gaps. ETHICS AND DISSEMINATION: Due to the nature of research, not involving humans or unpublished secondary data, approval of an ethics committee is not required. The dissemination of findings is planned via professional networks and publication in scientific open access journals.

Uptake of tumour necrosis factor-alpha inhibitor biosimilars for psoriasis: a drug utilization study from the British Association of Dermatologists Biologic and Immunomodulators Register (BADBIR).

BACKGROUND: Tumour necrosis factor-alpha inhibitors (TNFi) have revolutionized the treatment of moderate-to-severe psoriasis. Following patent expiry of the originator biologics, TNFi biosimilars became available, presenting the opportunity for significant reductions in drug costs. OBJECTIVES: To describe the uptake of TNFi biosimilars for psoriasis treatment in the UK and Ireland. METHODS: This observational cohort study utilizes data from the British Association of Dermatologists Biologic and Immunomodulators Register (BADBIR), a national pharmacovigilance study register for patients with psoriasis on systemic treatments. We analysed biosimilar uptake trends over time in nine geographical regions of England along with Wales, Scotland, Northern Ireland and the Republic of Ireland. We assessed the incidence of switching to biosimilars in an originator-user cohort (switchers). Patients on originators infliximab, etanercept and adalimumab at the time originator patents expired, entered the cohort on 1 February 2015, August 2015 and October 2018, respectively, and were followed up until 31 October 2021. Trends in biosimilar initiations were assessed in an adalimumab-naïve cohort who started adalimumab between 1 October 2018 and 31 July 2019 (starters). We assessed the associations between patient factors and originator-to-biosimilar switching and biosimilar initiation using a multivariable Cox regression model and a multivariable logistic regression model, respectively. RESULTS: Included in the originator-user cohort were 4202 patients (209 on infliximab, 742 on etanercept and 3251 on adalimumab). For infliximab, etanercept and adalimumab, respectively, the cumulative incidence of originator-to-biosimilar switching increased with time to 14.8%, 23.6% and 66.6% after 3 years. Across geographical regions, 3-year switching rates varied from 0% to 43.7% for infliximab; from 0% to 40.4% for etanercept; and from 12.5% to 84.3% for adalimumab. Out of the 528 patients included in the adalimumab-naïve cohort, 67.8% started on biosimilars. Originator-to-biosimilar switching and biosimilar initiation were more common in men and in patients who had lower Psoriasis Area and Severity Index at cohort entry. CONCLUSIONS: The uptake of biosimilars increased over time and varied considerably across the UK and Ireland; adalimumab had the highest biosimilar uptake rate compared with that of other TNFi drugs.

Imsidolimab, an anti-interleukin-36 receptor monoclonal antibody, for the treatment of generalized pustular psoriasis: results from the phase II GALLOP trial.

BACKGROUND: Generalized pustular psoriasis (GPP) is a systemic inflammatory disease that can be severe, debilitating and life threatening. Uncontrolled activation of interleukin (IL)-36 proinflammatory activity may underlie the pathogenesis of GPP. Currently, GPP-specific treatment options are limited. OBJECTIVES: To evaluate the efficacy and safety of the anti-IL-36 receptor antibody imsidolimab in patients with GPP. METHODS: In an open-label, single-arm, multiple-dose study, patients with GPP were treated with imsidolimab to assess clinical efficacy, tolerability and safety. Patients received an intravenous dose of imsidolimab 750 mg on day 1, followed by three subcutaneous doses of imsidolimab 100 mg administered on days 29, 57 and 85. The primary efficacy endpoint was the proportion of patients who achieved a clinical response at weeks 4 and 16 following treatment with imsidolimab, as measured by the Clinical Global Impression scale. RESULTS: Eight patients were enrolled and six completed the study. Responses were observed as early as day 3, most rapidly for pustulation relative to other manifestations of GPP, with continued and consistent improvement across multiple efficacy assessments at day 8, day 29 and through day 113. Most treatment-emergent adverse events (TEAEs) were mild to moderate in severity. No patient discontinued the study owing to a nonserious TEAE. Two patients experienced serious adverse events (SAEs); no deaths were reported. CONCLUSIONS: Imsidolimab demonstrated a rapid and sustained resolution of symptoms and pustular eruptions in patients with GPP. It was generally well tolerated, with an acceptable safety profile, and is advancing to phase III trials. These data support the targeting of IL-36 signalling with a specific antibody - imsidolimab - as a therapeutic option for this severely debilitating condition.