Spotlight on ixekizumab for the treatment of moderate-to-severe plaque psoriasis: design, development, and use in therapy

Interactions between neutrophils and T-helper 17 cells

Neutrophils comprise the majority of immune cells in human peripheral circulation, have potent antimicrobial activities, and are clinically significant in their abundance, heterogeneity, and subcellular localization. In the past few years, the role of neutrophils as components of the innate immune response has been studied in numerous ways, and these cells are crucial in fighting infections, autoimmune diseases, and cancer. T-helper 17 (Th17) cells that produce interleukin 17 (IL-17) are critical in fighting infections and maintaining mucosal immune homeostasis, whereas they mediate several autoimmune diseases. Neutrophils affect adaptive immune responses by interacting with adaptive immune cells. In this review, we describe the physiological roles of both Th17 cells and neutrophils and their interactions and briefly describe the pathological processes in which these two cell types participate. We provide a summary of relevant drugs targeting IL-17A and their clinical trials. Here, we highlight the interactions between Th17 cells and neutrophils in diverse pathophysiological situations.

Cannabinoid Compounds as a Pharmacotherapeutic Option for the Treatment of Non-Cancer Skin Diseases

The endocannabinoid system has been shown to be involved in various skin functions, such as melanogenesis and the maintenance of redox balance in skin cells exposed to UV radiation, as well as barrier functions, sebaceous gland activity, wound healing and the skin's immune response. In addition to the potential use of cannabinoids in the treatment and prevention of skin cancer, cannabinoid compounds and derivatives are of interest as potential systemic and topical applications for the treatment of various inflammatory, fibrotic and pruritic skin conditions. In this context, cannabinoid compounds have been successfully tested as a therapeutic option for the treatment of androgenetic alopecia, atopic and seborrhoeic dermatitis, dermatomyositis, asteatotic and atopic eczema, uraemic pruritis, scalp psoriasis, systemic sclerosis and venous leg ulcers. This review provides an insight into the current literature on cannabinoid compounds as potential medicines for the treatment of skin diseases.

What's new and what's next for biological and targeted synthetic treatments in psoriatic arthritis?

INTRODUCTION

Psoriatic arthritis (PsA) is a chronic arthritis typically associated with cutaneous psoriasis (PsO). Its pathogenesis is connected to an innate and acquired immune response, as well as genetic risk alleles. The extent of immunopathogenic mechanisms and the heterogenicity of clinical manifestation make the identification of patient-targeted therapies a critical issue, and the treatment decision challenging in patients' management.

AREAS COVERED

This review includes a brief overview of biological and small-molecule therapies, focusing on evidence from clinical trials and real-world data that support their use in PsA. We summarize novel and future possible therapeutic strategies, the importance that comorbidities have on selection of therapy and discuss the adverse event of each drug. Relevant papers for up to 1 August 2022 (trials, real-life studies, and reviews) regarding biologics and/or small molecules were summarized.

EXPERT OPINION

In recent years, the treatment of PsA has been revolutionized by new targeted therapies, which offer the opportunity to perform a tailored-tail management, considering risk factors, comorbidities, and the different PsA phenotypes. Growing experience with these new agents allows novel treatment approaches that may improve clinical outcomes for PsA patients, in terms of remission/low disease activity and quality of life.

Adherence and Persistence to Biological Drugs for Psoriasis: Systematic Review with Meta-Analysis

Despite the large number of biologics currently available for moderate-to-severe psoriasis, poor adherence and persistence to therapy represent the main issues for both the clinical and economic management of psoriasis. However, the data about adherence and persistence to biologics in psoriasis patients are conflicting. Our aim was to produce summary estimates of adherence and persistence to biologics in adult patients with psoriasis. We performed a systematic review and meta-analysis of observational studies, searching two databases (PubMed and Embase). Sixty-two records met the inclusion criteria, and a meta-analysis was conducted on fifty-five studies. Overall, the proportion of adherent and persistent patients to biological therapy was 0.61 (95% confidence interval: 0.48–0.73) and 0.63 (0.57–0.68), respectively. The highest proportions were found for ustekinumab, while the lowest ones were found for etanercept. The proportions of adherence and persistence to biological drugs in psoriasis patients are sub-optimal. Notably, both proportions largely differ between drugs, suggesting that a more rational use of biologics might ensure better management of psoriasis.

Genetic variants in IL-17A rs10484879 and serum levels of IL-17A are associated with psoriasis risk

Psoriasis is an inflammatory skin disease characterized by keratinocyte hyperproliferation with effective environmental and genetic factors. Recent studies showing that the IL-23/IL-17 axis plays a central role in the pathogenesis of the disease. Experimental and clinical studies suggest that IL-17A, an important regulatory effector cytokine in this pathway and triggers changes mainly in affected tissues. Based on the central role of IL-17A in the pathogenesis of psoriasis, we thought that variations in this gene could affect the susceptibility and severity of this disease. Therefore, in this study, we aimed to analyze whether IL-17A rs10484879 variant has an effect on psoriasis pathogenesis in Turkish population. In this case-control study, the study group consisting of 564 patient (188 psoriasis patients (66 males/122 females)/376 controls (132 males/244 females) and they were genotyped in terms of IL-17A (rs10484879) polymorphism with TaqMan 5 'Allelic Discrimination Test. IL-17A serum levels were measured with the Enzyme-linked immunosorbent assay (ELISA). The genotype distributions of the IL-17A rs10484879 polymorphism between the patient and control groups were statistically different in the TT genotype and it was observed more commonly in the patient group compared to the controls (p < 0.001). Similarly, the T allele was observed with a higher prevalence in the patient group compared to the controls (p = 0.007). IL-17A serum levels were associated with increased serum concentration, respectively, TT > GT > GG in all study groups (p < 0.05). We would like to report that IL-17A rs10484879 TT genotype and T allele are associated with increased risk of psoriasis in the Turkish population.

An updated guide in the management of psoriasis for every practitioner

BACKGROUND

Psoriasis is one of the most common chronic cutaneous skin disorders, having genetic and immunological components. It is currently unknown what exactly triggers it, or how far reaching are the etiological factors, although great strides have been made in uncovering the pathophysiological cascade. Presently, there is a wide diversity of treatment methods for psoriasis, yet not all are applicable for each patient. Selection of both drug and dosage depends on both the knowledge and experience of the treating dermatologist and also on the specific characteristics of each patient. Therefore, the treating physicians should be made aware of the management possibilities, their advantages and their side effects.

METHODS

We have performed a non-systematic literature review on the current treatment methods for psoriasis. We have included the studies, articles, and prescription information that provided the most relevant information regarding each therapeutic agent. Afterward, we divided the treatment methods according to delivery and illustrated the management protocols for adult, paediatric, and pregnant patients.

DISCUSSION AND CONCLUSIONS

Current therapies are divided into topical drugs, phototherapy, systemic and biological agents. Topical therapies and phototherapy are generally the first and second line of management respectively, being typically effective in treating mild to moderate forms of psoriasis. On the other hand, the chronic moderate to severe forms usually benefit from systemic drugs, whereas biologic agents are reserved for severe or unremitting cases, especially those suffering from psoriatic arthritis. Also of importance is the understanding of the pathophysiological mechanisms in psoriasis and how the selected drugs interfere in the pathological cascade. Furthermore, physicians should be able to recommend the appropriate therapy not only for adults but also for paediatric and pregnant patients as well. In the following manuscript, we present an updated version of these management options, alongside their indications, posology and most common side effects, a guide that may be useful for every practitioner in this field.

Interleukin-17 and Interleukin-23: A Narrative Review of Mechanisms of Action in Psoriasis and Associated Comorbidities

Psoriasis is an immune-mediated inflammatory skin disease associated with numerous inflammatory comorbidities, including increased cardiovascular risk. The interleukin (IL)-23/IL-17 axis plays a central role in the immunopathogenesis of psoriasis and related comorbidities by acting to stimulate keratinocyte hyperproliferation and feed-forwarding circuits of perpetual T cell-mediated inflammation. IL-17 plays an important role in the downstream portion of the psoriatic inflammatory cascade. This review discusses the distinct mechanisms of action of IL-17 and IL-23 in the immunopathogenesis of psoriasis and related comorbidities plus the significant therapeutic benefits of selectively inhibiting these cytokines in patients with moderate to severe plaque psoriasis.

Drug survival of ixekizumab, TNF inhibitors, and other IL-17 inhibitors in real-world patients with psoriasis: The Corrona Psoriasis Registry

To compare drug survival of ixekizumab to other IL‐17 inhibitors (IL‐17i) and TNF inhibitors (TNFi) among patients with psoriasis (PsO) in a real‐world setting. Participants included adult PsO patients enrolled in the Corrona Psoriasis Registry who initiated ixekizumab, TNFi, or other IL‐17i between 16 March 2016 to 10 August 2019 and completed ≥1 follow‐up visit. Multivariable adjusted hazard ratios (HR) were calculated to estimate the risk for drug discontinuation in the ixekizumab group relative to the other drugs. Among the 1604 drug initiations, 552 initiated ixekizumab, 450 initiated TNFi, and 602 initiated other IL‐17i. Mean age was 51 years, 49% were women, and 52% were obese (BMI > 30). Ixekizumab patients had a higher proportion of patients with PASI >12 at drug initiation (24%) than TNFi (15%) and other IL‐17i (19%). Over a median of 11 months of follow‐up, 723/1604 (45%) drug discontinuations occurred. Persistence of ixekizumab, TNFi, and other IL‐17i at 24‐months were 68%, 33%, and 46%, among biologic‐naïve patients (n = 543), and 46%, 23%, and 36%, for biologic‐experienced patients (n = 1061), respectively. Ixekizumab patients had a 64% lower risk of discontinuation vs TNFi (HR = 0.36; 95% CI 0.27‐0.47) and a 31% lower risk vs other IL‐17i (HR = 0.69, 95% CI 0.55‐0.87) after adjustment for biologic experience and other covariates. HRs were similar when limited to patients with moderate‐to‐severe PsO (BSA > 3, PASI > 3, and IGA > 1, n = 1076) at initiation. In our study of real‐world patients with PsO, initiators of ixekizumab had more prolonged drug survival than both initiators of TNFi and other IL‐17i up to 2 years of follow‐up.

Epidemiological Variations in the Global Burden of Psoriasis, an Analysis With Trends From 1990 to 2017

Background: Although there have been many epidemiological studies, research focusing on psoriasis' health burden on a global scale is still lacking. Trends and variations in the global health burden of psoriasis are evaluated by time, age, gender, geographical location, and socioeconomic status, using disability-adjusted life years (DALYs) from the Global Burden of Disease Study.

Methods: The health burden of psoriasis was evaluated by DALYs, which combined years lost to disability (a morbidity component) with years of life lost (a mortality component). The global and national DALYs number, crude DALYs rate, and age-standardized DALYs rate were obtained from the GBD 2017 study database. The corresponding human development index (HDI) was collected from the United Nations Development Programme.

Results: From 1990 to 2017, the DALYs number and crude DALYs rate due to psoriasis increased by 73 and 22%, respectively. In comparison, the age-standardized DALYs rate showed a slight increase. Patients in the age range of 65–69 years bear a more significant psoriasis burden. Both males and females showed an increasing trend in burden caused by psoriasis over the past 27 years, with females bearing a more significant psoriasis burden than males. The health burden of psoriasis was substantially unequal in geography with a Gini coefficient of 0.27. The concentration indexes indicated a socioeconomic associated inequality in psoriasis burden with values of 0.22, accounting for 48.64% variance across countries (R2 = 0.4864, p < 0.001). Between-nation inequality in the distribution of psoriasis burden continued to decline throughout the past 27 years. Gini coefficients of psoriasis burden decreased from 0.280 in 1990 to 0.265 in 2017. The concentration indexes indicated the same trend with 0.236 in the 1990s and 0.223 in 2017.

Conclusions: Global health progress in psoriasis together with inequality in the past few decades. Although the inequality of psoriasis burden has shown some improvement during the past 27 years, disparities still exist in age, gender, geographical location, as well as socioeconomic status. The findings of this study highlight the global importance of psoriasis and is important in policy planning for psoriasis services on a global scale.

An Update for the Clinician on Biologics for the Treatment of Psoriatic Arthritis

Psoriatic arthritis (PsA) is a chronic inflammatory arthropathy typically associated with psoriasis (PsO). The pathogenesis is strictly related to the association among the presence of genetic risk alleles and innate and acquired immune response with dramatic consequences on bone remodeling. Clinically, PsA patients may present heterogenicity of articular and periarticular manifestations that may be associated with the presence of comorbidities making treatment decision challenging in patients management. The identification of patient-targeted therapies is still a critical issue. Actually, several biological and synthetic drugs are promising in terms of efficacy and safety profile. National and international treatment recommendations support clinicians in the decision of the best treatment, although they may have limits basically related to updates and different outcomes included in the clinical studies evaluated. The aim of this narrative review is therefore to give guidance for clinicians for PsA patients treatment. For this purpose, we evaluated evidence on biological therapies efficacy used for PsA treatment. Specifically, we reviewed data on biological therapies, Janus kinases (JAK) inhibitors, and drugs with a new mechanism of action that are part of the treatment pipeline. The concept of "switching" and "swapping" is also described, as well as data concerning special populations such as pregnant women and elderly patients.

Tackling the autoimmune side in Spondyloarthritis: A systematic review

Spondyloarthritis (SpA) are a heterogeneous group of inflammatory chronic diseases characterized by sharing common pathogenic, clinical and radiologic features. The aim of this review is to support clinicians in understanding and managing this complex disease, from pathogenesis to therapeutic targets, through a systematic review of the current literature in accordance with PRISMA guidelines and checklist. HLA-B27 has been found to be associated with axial involvement either in SA and in PsA patients: it might be involved through presentation of an "arthritogenic peptide" to autoreactive CD8+ T cells or might accumulate in misfolded form and induce production pro-inflammatory cytokines by binding to several innate immune receptors. This genetic background in combination with mechanical stress leads to the activation of both innate and acquired immune responses as well as a possible role of autoimmunity in SpA pathogenesis. The release of IL-23 and IL-17 is relevant for their systemic and local effect on bone, inducing the activation of osteoclasts. Thus, the regulatory role of IL-17 on fibroblasts, osteoblasts and chondrocytes has an impact in both synovial inflammation and joint destruction. Innovative therapies targeting IL-12/23 and IL-17 and the use of small targeted synthetic molecules, as JAK-inhibitors, proved to be effective in SpA patients representing an alternative strategy to TNF-inhibitors.

Predictive role of vitamin A serum concentration in psoriatic patients treated with IL-17 inhibitors to prevent skin and systemic fungal infections

The use of biological drugs in psoriasis is replacing traditional therapies due to their specific mechanism and limited side effects. However, the use of Interleukin 17 inhibitors and the modification of its cytokine pathway could favor the risk of fungal infections. All-trans retinoic acid is an active metabolite of vitamin A with anti-inflammatory and immunoregulatory properties through its capacity to stimulate both innate and adaptive immunity and to its effects on proliferation, differentiation and apoptosis in a variety of immune cells. Furthermore, it has been recently discovered that All-trans retinoic acid has a direct fungistatic effect against Candida and Aspergillus Fumigatus. On the basis of these new insights, in the current review, we suggest that the evaluation of serum level of All-trans retinoic acid or vitamin A should be considered as a predictive marker for the development of fungal infections among psoriatic patients treated with Interleukin 17 inhibitors. In clinical practice, vitamin A test could be added in the routine hospital diagnostic management for a better selection of psoriatic patients eligible to Interleukin 17 inhibitors.

Ixekizumab for the treatment of psoriasis: up-to-date

Introduction: Ixekizumab (an IL-17A antagonist) is a biologic therapeutic licensed for use in moderate-to-severe plaque psoriasis and psoriatic arthritis. IL-17 antagonists (also including Secukinumab and Brodalumab) represent a new generation of biologic therapy with rapid and high response rates, quickly becoming a crucial part of the psoriasis treatment armamentarium.Areas covered: In this review, we describe how IL-17A antagonists disrupt inflammatory cascades in psoriasis and summarize results from clinical trials examining the safety and efficacy of ixekizumab against placebo and comparators.Expert opinion: Ixekizumab induces a 75% reduction in psoriasis area severity index (PASI 75) in 89% of patients after 12 weeks and after 1 year, PASI 75 is maintained in 80% of patients. Ixekizumab is superior to both etanercept and ustekinumab, however, further comparator trials are needed to determine superiority between newer agents. Network meta-analysis suggests that ixekizumab is one of the most rapid and efficacious agents for treating psoriasis, but ideally more long-term real-world data are needed to determine the persistence of response. Candida may be commonly encountered during treatment and IL-17 agents should be avoided in patients with inflammatory bowel disease. Overall, ixekizumab represents an efficacious and well-studied therapeutic that can offer biologic-naïve and bio-failure patients durable disease control.

An update on pathogenesis of psoriatic arthritis and potential therapeutic targets

Introduction: Innate immune response and bone remodeling are key factors contributing to the pathogenesis of psoriatic arthritis (PsA). Moreover, the evidence of autoantibodies in patients' sera suggests an autoimmune side in PsA. Besides the immune pathways, studies strongly support the role of genetic risk alleles in affecting the clinical heterogeneity of PsA as well as the response to therapy. A good clinical response to treatment, indeed, represents a challenge in PsA patients and the identification of patient-targeted therapies is still a critical issue. Areas covered: We performed a systematic review aiming at describing new evidence on PsA pathogenesis and treatments. Reported items for systematic reviews (PRISMA checklist) were analyzed. Studies included from the PubMed database addressed the following items: innate immunity, autoimmunity, bone remodeling, and therapeutic targets in PsA; time frame of research 1970-2019. Specifically, we reviewed data on IL-17 inhibitors, abatacept, JAK inhibitors, ABT 122, and A (3) adenosine receptors agonist, CF101. Expert opinion: In PsA an intriguing pathogenetic network has been documented. Several biological and synthetic drugs are promising in terms of efficacy and safety profile.

Advances in Understanding the Immunological Pathways in Psoriasis

Psoriasis vulgaris is a chronic, immune-mediated, inflammatory, polygenic skin disorder affecting approximately 2% of the population. It has a great impact on quality of life; patients often experience depression, anxiety, stigma as well as suicidal behavior. Even though psoriasis is one of the most studied dermatological conditions, the pathogenesis of the disease is still not completely elucidated. The complex interactions between keratinocytes, dendritic cells, T-lymphocytes, neutrophils and mast cells are responsible for the histopathological changes seen in psoriasis. The pathogenic model leading to the formation of psoriatic plaques has however evolved a lot over the years. There is now enough evidence to support the role of interleukin (IL) -23, IL-17, IL-22, T helper (Th) -17 cells, Th-22 cells, T regulatory cells, transforming growth factor (TGF)-β1 and IL-10 in the pathogenesis of the disease. Moreover, several inflammatory and anti-inflammatory molecules are currently being investigated, some of them showing promising results. The aim of this paper is to look over the most recent advances in the immunological pathways involved in the pathogenesis of psoriasis vulgaris.

Clinical utility of ixekizumab in the treatment of moderate-to-severe plaque psoriasis

Psoriasis vulgaris is a chronic, immune-mediated systemic disease that affectŝ7.5 million people in the US. It can be treated with many therapies, often in combination, which include topicals, phototherapy, oral systemics, and biologics. Biologic agents target specific components of the immune system involved in the pathogenesis of psoriasis including TNF-alpha, IL-12, IL-17, and IL-23. The biologic ixekizumab, approved for the treatment of moderate–severe plaque psoriasis in the US, targets IL-17. This review describes the role of IL-17 in psoriasis, the mechanism by which ixekizumab targets this cytokine, and the clinical utility of ixekizumab.