Pharmacological Management of Pediatric Pustular Psoriasis

Clinical advances in biological therapy for generalized pustular psoriasis: a review

INTRODUCTION

In 2022, U.S. Food and Drug Administration (FDA) approved the first biologics, intravenous spesolimab, for acute flare of generalized pustular psoriasis (GPP). The drug works by blocking IL-36 signaling, the key pathway of GPP. Among the known mutations causing GPP, IL36RN mutations are most common, and the presence of IL36RN mutations had been found to affect the clinical manifestations and treatment response of GPP.

AREAS COVERED

Literature search was conducted in PubMed, Embase and ClinicalTrials.gov for relevant studies discussing biologic treatment for GPP with special emphasis on larger studies, pediatric group, pregnant women, and the influence of IL36RN mutation on the effectiveness of biologics.

EXPERT OPINION

The approval of spesolimab for GPP flare treatment marks a new era. However, whether spesolimab will be placed as the treatment of choice remains unknown, considering its higher cost, lack of direct comparison with existing biologics, and uncertain effects on co-existing plaque-type psoriasis. However, the demonstration of numerically better efficacy for patients carrying pathogenic IL36RN mutations suggests the role of pharmacogenetics in the choices of GPP treatment. Future randomized studies are warranted to investigate the effectiveness and safety of biologics for GPP in pediatric and pregnant groups.

Transcriptomic responses of peripheral blood mononuclear cells to cyclosporin and etanercept in a female infant with juvenile generalized pustular psoriasis

Generalized pustular psoriasis (GPP) is a rare but severe form of psoriasis. An early onset of the diseases is correlated with mutations among IL36RN, CARD14, AP1S3, MPO and SERPINA3 genes. Systemic biological agents including anti-TNF-α, anti-IL-17, anti-IL-12/IL-23, anti-IL1R, anti-IL1β and anti-IL-36R act as novel treatment methods for GPP. Herein we report a female infant clinically diagnosed with GPP since she was 10-month-old. Results of whole-exome sequencing (WES) and Sanger sequencing revealed a reported heterozygous IL36RN (c.115+6T>C) and another reported heterozygous SERPINA3 frame-shifting variant (c.1247_1248del). Initial cyclosporin treatment for the patient led to a partial remission of the symptoms. However, the patient reached nearly total remission of pustules and erythema after anti-TNF-α inhibitor etanercept treatment. Results of further RNA sequencing (RNA-seq) done on peripheral blood mononuclear cells correlated with the clinical responses, showing that cyclosporin suppressed a portion of the neutrophil-related genes, while most genes associated with neutrophil activation, neutrophil-mediated immunity and degranulation were downregulated by the subsequent etanercept treatment. We report this case to demonstrate WES and RNA-seq in combination could come in handy in reaching a precise diagnosis and in evaluating or even predicting the molecular alterations underlying clinical treatment effectiveness.

Efficacy of adalimumab in pediatric generalized pustular psoriasis: case series and literature review

BACKGROUND

Generalized pustular psoriasis (GPP) is a rare, severe, and sometimes fatal form of childhood psoriasis. The first line therapies include acitretin, cyclosporin A, and methotrexate which take effect slowly and have varying long-term side effects for children. Recently, the anti-tumor necrosis factor-alpha (TNF-α), adalimumab has shown efficacy in adult patients with pustular psoriasis; however, there is lack of evidence of its usage in the pediatric population.

METHODS

Data on efficacy of adalimumab in treating pediatric GPP along with a literature review are presented.

RESULTS

A total of seven patients had marked clearance and reduction in PGA and systemic/laboratory score within the first week of first injection and achieved almost complete clearance of skin lesions by 1-month follow up. In literature, adalimumab treating pustular psoriasis in pediatric has been described in six children who failed in prior treatment. All six patients showed a satisfactory therapeutic effect.

CONCLUSIONS

Subcutaneous injection of adalimumab every other week in the treatment of children with GPP has significant clinical efficacy with rapid clearance of skin lesions, providing a novel alternative for children with pustular psoriasis who responded poorly to traditional treatment or are not suitable for traditional treatment.

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.

Targeted Therapy for Pediatric Psoriasis

Psoriasis is an inflammatory immune-mediated skin disease that affects both adults and children. Increased understanding of its pathogenesis has led to the development of highly effective therapeutic solutions in the form of biological drugs for adult patients with severe forms of the disease. The unpredictability of the action of adult-approved drugs in pediatric populations limited their usage in these patients for several years. However, this scenario has been changing, particularly in the last decade, increasing our knowledge of the clinical efficacy and safety of these drugs in pediatric populations. The approval/extensions to approvals of several biological agents throughout the year 2020 makes it important to update the topic. Five biological agents (etanercept, adalimumab, ustekinumab, secukinumab, and ixekizumab) have been approved by the European Medicines Agency for the treatment of psoriasis in pediatric populations, and three of them (etanercept, ustekinumab, and ixekizumab) were also approved by the US FDA for the same purpose. In total, 17 clinical trials of several distinct targeted therapies (tumor necrosis factor, interleukin [IL]-17 and IL-23, and phosphodiesterase-4 inhibitors) are ongoing in pediatric patients and will certainly provide crucial data on the subject, which could ultimately improve the armamentarium we have to target psoriasis in this special population.

Successful treatment of paediatric generalized pustular psoriasis with secukinumab: a case series

Generalized Pustular Psoriasis (GPP) is a rare, severe, life-threatening form of psoriasis and accounts for up to 13.1% of all childhood psoriasis. Common first-line systemic treatment for pediatric patients with GPP include oral acitretin, cyclosporin and methotrexate which have varying efficacy and side effects but multiple interventions are often needed to induce remission and maintain long term control. Recently, the anti IL 17 A monoclonal antibody secukinumab have been shown to be effective in adult patients with GPP; however, there is lack of evidence of its usage in the pediatric population. We describe a case series of 4 pediatric patients with GPP who were treated with off-label use of secukinumab. All four patients had marked clearance and reduction in Generalized Pustular Psoriasis Area & Severity Score (GPPASI) within first 48 h of first injection with subsequent almost complete to complete clearance of skin lesions by 1 month follow up. In conclusion, secukinumab was found to be successful in inducing remission, with rapid clearance and maintaining remission, with or without combination with other systemic agents for pediatric GPP.

Comparison of psoriasis guidelines for use of IL-23 inhibitors in the United States and United Kingdom: a critical appraisal and comprehensive review

PURPOSE

This review article aims to compare global dermatologic organizations and the clinical practice guidelines available for the use of interleukin (IL)-23 inhibitors in the treatment of psoriasis.

MATERIALS AND METHODS

A literature review encompassing systemic therapies for the treatment of psoriasis was conducted. Guidelines from the American Academy of Dermatology (AAD)-National Psoriasis Foundation (NPF), the National Institute for Health and Care Excellence (NICE), and the British Association of Dermatologists (BAD) served as the main comparators in this review.

RESULTS

Of the American and European guidelines available for use of IL-23 inhibitors, several organizations are in agreement regarding the dosage and indications of guselkumab, tildrakizumab, and risankizumab. However, there are differences as well as insufficient recommendations concerning laboratory monitoring and screenings as well as contraindications to therapy.

CONCLUSION

IL-23 inhibitors are safe and efficacious therapeutic options for patients with psoriasis and should be considered as a potential first-line therapy alone or in combination with topical medications, phototherapy, and other systemic non-biologic agents. Consideration should be given to the evidence-based guidelines of global dermatologic organizations to help guide therapeutic decisions.