Emerging systemic drugs in the treatment of plaque psoriasis

Deucravacitinib: moderate-to-severe plaque psoriasis preventable?

Psoriasis is a persistent, inflammatory, and autoimmune condition that is difficult to treat. Estimates of the prevalence of psoriasis in people range from 0.27 % (95 % confidence interval 0.17 to 0.36) to 11.4 %, depending on factors such as age, sex, geography, ethnicity, genetics, and environmental factors. While systemic treatments are typically required for patients with moderate-to-severe instances of psoriasis, topical therapies are frequently effective for treating minor forms. In fact, phototherapy is frequently constrained by logistical considerations, and conventional systemic therapies are frequently avoided due to contraindications or the danger of adverse outcomes. In order to better serve the patient and achieve a greater level of quality of life, especially in order to sustain long-term efficacy, there is still a need for innovative therapies, which are always welcomed. Deucravacitinib is a first-in-class oral tyrosine kinase 2 (TYK2) inhibitor that is extremely selective. Through an allosteric mechanism, it stabilises an inhibitory connection between the regulatory and catalytic domains of TYK2's pseudokinase regulatory domain, which is catalytically inactive. This can be used to treat a variety of immune-mediated conditions, such as inflammatory bowel disease, lupus, psoriatic arthritis, and psoriasis. US-FDA has approved this drug on 9 September 2022 for the treatment of adults with moderate-to-severe plaque psoriasis who are candidates for systemic therapy or phototherapy. This article aims to review the current knowledge on the efficacy and safety of deucravacitinib for the management of psoriasis.

Efficacy and safety of deucravacitinib for the management of psoriasis: a drug safety evaluation

INTRODUCTION

Nowadays, despite the wide availability of biological drugs and apremilast for psoriasis management, there is always a need for new therapies to customize the therapeutic approach on the basis of the patient's clinical features and comorbidities, especially in order to achieve a prolonged therapeutic response. Thus, new treatment strategies are required to offer patients a personalized approach. In this scenario, major knowledge on psoriasis pathogenesis led to the development of deucravacitinib, an orally administered selective TYK2 inhibitor.

AREAS COVERED

The aim of this manuscript is to review the current literature on the effectiveness and safety of deucravacitinib in psoriasis to offer readers a wide perspective. The current English literature was analyzed using the PubMed, Google Scholar, Embase, Cochrane Skin, and clinicaltrials.gov databases, selecting the most relevant manuscripts.

EXPERT OPINION

Deucravacitinib appears to be an innovative weapon for the management of moderate to severe psoriasis. Despite its efficacy and safety profiles have been revealed by RCTs, real-life data are still scant. Certainly, deucravacitinib broadens the range of therapeutic alternatives for psoriasis patients, thus enhancing the holistic and personalized approaches required for the treatment of this disease.

Therapeutic Potential of Targeting the JAK/STAT Pathway in Psoriasis: Focus on TYK2 Inhibition

Psoriasis is an inflammatory skin disease with a chronic relapsing course and an often-detrimental impact on patients' quality of life. Thanks to incredible advances in research over the past few decades, the therapeutic armamentarium of psoriasis is now reasonably broad and structured, with several therapeutic agents that have demonstrated successful long-term control of this condition. However, there are still unfulfilled gaps resulting from the inherent limitations of existing therapies, which have paved the way for the identification of new therapeutic strategies or the improvement of existing ones. A great deal of attention has recently been paid to the JAK/STAT pathway, playing a crucial role in chronic inflammatory skin diseases, including psoriasis. Indeed, in a disease with such a complex pathogenesis, the possibility to antagonize multiple molecular pathways via JAK/STAT inhibition offers an undeniable therapeutic advantage. However, data from clinical trials evaluating the use of oral JAK inhibitors in immune-mediated disorders, such as RA, have arisen safety concerns, suggesting a potentially increased risk of class-specific AEs such as infections, venous thromboembolism, and malignancies. New molecules are currently under investigation for the treatment of psoriasis, such as deucravacitinib, an oral selective inhibitor that binds to the regulatory domain of TYK2, brepocitinib (PF-06700841) and PF-06826647 that bind to the active site in the catalytic domain. Due to the selective TYK2 blockade allowing the inhibition of key cytokine-mediated signals, such as those induced by IL-12 and IL-23, anti-TYK2 agents appear to be very promising as the safety profile seems to be superior compared with pan-JAK inhibitors. The aim of our review is to thoroughly explore the rationale behind the usage of JAK inhibitors in PsO, their efficacy and safety profiles, with a special focus on oral TYK2 inhibitors, as well as to provide a forward-looking update on novel therapeutic strategies targeting the TYK2 pathway in psoriasis.

Unmet Needs and Treatment Preference of Systemic Treatments for Moderate-to-Severe Psoriasis from the Perspectives of Patients and Dermatologists in China

INTRODUCTION

The treatment options for moderate to severe psoriasis (msPsO) in China have been greatly increased with the approvals of biologics. However, the unmet needs and treatment preferences of systemic treatments for msPsO in China remain unclarified.

METHODS

Fifty dermatologists and 300 patients with msPsO (41% with severe psoriasis) were surveyed for effectiveness, safety, treatment convenience, and treatment preferences (using a choice-based conjoint questionnaire). Descriptive statistics and conjoint simulation analyses were employed to summarize survey information and assess treatment preferences.

RESULTS

Both patients and dermatologists reported shorter treatment duration for oral drugs (2.7-6.2 months) than that for biologics (9.5-17.0 months). The most frequently reported treatment discontinuation reasons by the surveyed patients and dermatologists were unsatisfactory effectiveness (average 84.5%) for oral drugs and loss of efficacy over time (average 68.5%) for biologics. Commonly reported treatment inconveniences included regular lab tests for traditional oral drugs (average 71.5%) and administration assistance for biologics (average 58.0%). Injection site reactions (average 51.5%) and needle fear (average 35.5%) were frequently reported for biologics among the surveyed patients and dermatologists. Once-daily oral treatment was preferred over biweekly subcutaneous injection treatment when the two had comparable attributes (average in patients 87.1% vs. 12.9%; average in dermatologists 93.4% vs. 6.6%).

CONCLUSIONS

Unmet needs of systemic treatments remain for msPsO in China. Once-daily oral treatment is preferred over biweekly subcutaneous injections to treat msPsO when other treatment attributes are comparable.

Adenosine A2B receptor agonist improves epidermal barrier integrity in a murine model of epidermal hyperplasia

Adenosine regulates multiple physiological processes through the activation of four receptor subtypes, of which the A2B adenosine receptor (A2BAR) has the lowest affinity for adenosine. Being the adenosine receptor subtype most prominently expressed in epidermis, we recently described the antiproliferative and anti-inflammatory effect of the selective A2BAR agonist BAY60-6583 (BAY) in human keratinocytes stimulated with 12-O-tetradecanoylphorbol-13-acetate (TPA), so we sought to establish the effect of topical application of BAY in a model of murine epidermal hyperplasia. Topical application of BAY (1 or 10 μg/site) prevented the inflammatory reaction and skin lesions induced by TPA, minimizing hyperproliferation and acanthosis, as well as the expression of specific markers of proliferative keratinocytes. On the other hand, pre-treatment with the selective A2BAR antagonist, PSB-1115 (PSB, 5 or 50 μg/site) reversed these beneficial effects. Additionally, BAY application normalized the expression of epidermal barrier proteins, whose integrity is altered in inflammatory skin diseases, while treatment with the antagonist alone worsened it. Our results, besides confirming the anti-inflammatory and antiproliferative effects of the A2BAR agonist, further demonstrate a role of A2BAR activation to preserve the epidermal barrier. Therefore, the activation of A2BAR may constitute a possible new pharmacological target for the treatment of skin inflammatory diseases such as psoriasis.

Targeting TYK2 for Fighting Diseases: Recent Advance of TYK2 Inhibitors

TYK2 (tyrosine-protein kinase 2) is a non-receptor protein kinase belonging to the JAK family and is closely associated with various diseases, such as psoriasis, inflammatory bowel disease, systemic lupus erythematosus. TYK2 activates the downstream proteins STAT1-5 by participating in the signal transduction of immune factors such as IL-12, IL-23, and IL-10, resulting in immune expression. The activity of the inhibitor TYK2 can effectively block the transduction of excessive immune signals and treat diseases. TYK2 inhibitors are divided into two types of inhibitors according to the different binding sites. One is a TYK2 inhibitor that binds to JH2 and inhibits its activity through an allosteric mechanism. The representative inhibitor is BMS-986165, developed by Bristol-Myers Squibb. The other class binds to the JH1 adenosine triphosphate (ATP) site and prevents the catalytic activity of the kinase by blocking ATP and downstream phosphorylation. This paper mainly introduces the protein structure, signaling pathway, synthesis, structure-activity relationship and clinical research of TYK2 inhibitors.

Deucravacitinib in the treatment of psoriasis

PURPOSE OF THE ARTICLE

Psoriasis is a chronic, immune-mediated, skin disease with a significantly negative impact on patients' quality of life. Moderate-to-severe disease often requires systemic therapies and currently available ones still have numerous disadvantages or limitations. Tyrosine kinase 2 (TYK2) mediates immune signaling of IL-12, IL-23, and type I interferons, without interfering with other critical systemic functions. This article aims to review the current knowledge on deucravacitinib, a new oral drug which selectively inhibits TYK2, granting it a low risk of off-target effects.

MATERIALS AND METHODS

A review of the published literature was conducted using the PubMed database, published abstracts and virtual presentations from scientific meetings, data from industry press releases, and results published on ClinicalTrials.gov regarding the deucravacitinib for the treatment of psoriasis. Manuscripts with trial results, case series, clinical trial data from ClinicalTrials.gov, and articles highlighting expert perspectives on the topic of the article were selected.

RESULTS

Two phase 3, 52-week trials evaluated deucravacitinib 6 mg against placebo and apremilast - POETYK PSO-1 and PSO-2, enrolling 1688 patients with moderate-to-severe psoriasis. At week 16, over 50% of patients treated with deucravacitinib reached PASI75, significantly superior to placebo and apremilast. Symptomatic improvement was also reported, with greater impact on itch. Deucravacitinib was well tolerated and safe. There were no reports of serious infections, thromboembolic events, or laboratory abnormalities. Persistent efficacy and consistent safety profiles were reported for up to 2 years.

CONCLUSIONS

Deucravacitinib has the potential to become a safe, effective, and well-tolerated treatment for patients with moderate-to-severe disease. Future studies will be important to determine the exact role of this drug in the treatment of psoriasis.

Phytochemical investigation, structural elucidation, in silico study and anti-psoriatic activity of potent bioactive from Betula utilis

Psoriasis is a chronic autoimmune pathological condition characterized by hyperactivation of proinflammatory cytokines (IL-6, TNF-α, IL-17, IL-23, etc.). Severe drug-associated toxicities like hepatotoxicity and nephrotoxicity (Methotrexate), teratogenicity (Tazarotene), hypercholesterolemia (Cyclosporine) and hypercalcemia (tacalcitol), are the forefront challenges that demand an alternative approach for the treatment of psoriasis. In the present study, a natural lead molecule 'Betulin' (BE, lup-20(29)-ene-3b,28-diol) was isolated from Betula utilis and subsequently, structure-based molecular docking was employed to identify the molecular target for psoriasis. The computational analysis reflects better affinity of BE towards pro-inflammatory cytokine as compared to standard drugs. Apart from this BE shows a greater affinity towards the overexpressed Glut-1 receptor in comparison to standard drug Metformin (Met). Based on the in silico screening the isolated lead compound was further processed for the evaluation of anti-psoriatic activity via imiquimod (IMQ 5%) induced psoriasis-like skin inflammation model. In vivo screening models were characterized by different parameters (psoriasis area and severity index (PASI) scores, macroscopically and behavioral evaluation, splenomegaly, cytokine levels and histological changes) and compared among the experimental groups. The experimental finding reflects comparable results of PASI score, i.e., 57.14% and 61.9% recovery of test BE-solution (180 mg/kg) and standard Betamethasone di-propionate ointment (BD-oint.0.5 mg/g), respectively. Focusing on other parameters, BE shows relative results such as an enhanced macroscopically with behavioral conditions, reducing the expression of proinflammatory cytokine as well as restoring histological changes with that of BD. These findings suggest that BE-isolated phytoconstituents from Betula utilis could be a potential agent and a step closer to psoriasis treatment. HIGHLIGHTPsoriasis is a multifaceted, immunologically mediated disease consequences production of high levels of proinflammatory mediators and overexpression of Glut-1 transporters that trigger keratinocyte proliferation and inflammatory cascades.A Himalayan silver birch, Betula utilis (Bhojpatra) contains many steroidal terpenes which are responsible for various pharmacological activities that could be exploited in drug development in psoriasis.The computational analysis of BE reflects a better affinity toward the proinflammatory cytokines with their target receptors and indicates a satisfactory range with a slight deviation from Jorgensen and Lipinski's rule and possesses a significant drug choice for psoriasis.Preclinical findings of BE-solution (BE-sol) give a positive response towards IMQ-induced psoriasis-like skin inflammation model.[Figure: see text]Communicated by Ramaswamy H. Sarma.

Effectiveness and Safety of Deucravacitinib for the Management of Psoriasis: A Review of the Current Literature

Psoriasis management may be challenging, particularly for moderate-to-severe forms of the disease. Indeed, conventional systemic treatments are often avoided for contraindications or the risk of adverse events as well as phototherapy is often limited by logistic concerns. Despite the development of biological drugs and small molecules revolutionized the treatment options showing promising results in terms of safety and effectiveness, some limitations remain. Thus, there is still a need for new therapies that are always welcome in order to tailor the treatment to the patient and to have a higher level of performance, especially in order to maintain long-term effectiveness. In this scenario, deucravacitinib, an oral small molecule which selectively inhibits Tyrosine Kinase 2, may represent a promising weapon in psoriasis management. The aim of our manuscript is to review the current knowledge on the efficacy and safety of deucravacitinib for the management of psoriasis.

Psoriasis: Interplay between dysbiosis and host immune system

With advancement in human microbiome research, an increasing number of scientific evidences have endorsed the key role of both gut and skin microbiota in the pathogenesis of psoriasis. Microbiome dysbiosis, characterized by altered diversity and composition, as well as rise of pathobionts, have been identified as possible triggers for recurrent episodes of psoriasis. Mechanistically, gut dysbiosis leads to "leaky gut syndrome" via disruption of epithelial bilayer, thereby, resulting in translocation of bacteria and other endotoxins to systemic circulation, which in turn, results in inflammatory response. Similarly, skin dysbiosis disrupts the cutaneous homeostasis, leading to invasion of bacteria and other pathogens to deeper layers of skin or even systemic circulation further enhanced by injury caused by pruritus-induced scratching, and elicit innate and adaptive inflammation. The present review explores the correlation of both skin and gut microbiota dysbiosis with psoriasis. Also, the studies highlighting the potential of bacteriotherapeutic approaches including probiotics, prebiotics, metabiotics, and fecal microbiota transplantation for the management of psoriasis have been discussed.

Apremilast in the Treatment of Plaque Psoriasis: Differential Use in Psoriasis

Small molecule medications like apremilast are emerging as promising options for patients with psoriasis and other inflammatory conditions. Apremilast was approved by the Food and Drug Administration in 2014 for the management of both psoriasis and psoriatic arthritis. Apremilast inhibits phosphodiesterase-4, which increases the intracellular levels of cyclic AMP, thereby reducing inflammatory cytokine production. This review aims to discuss the published evidence and evaluate the differential use of apremilast in plaque psoriasis of the body and scalp, nail psoriasis, and palmoplantar psoriasis. In clinical trials, apremilast effectively reduced the severity of different dermatological manifestations of psoriasis and improved patients' quality of life. It has an acceptable safety profile and is generally well-tolerated. Oral medications like apremilast offer an alternative route of administration which can be more convenient and appropriate for some patients. Additionally, pharmacoeconomic analyses of available anti-psoriatic systemic agents favor apremilast as a cost-effective therapeutic option.

Dimethyl Fumarate's Effectiveness and Safety in Psoriasis: A Real-Life Experience During the COVID-19 Pandemic

Introduction

Dimethyl fumarate (DMF) is approved as oral systemic treatment for moderate-to-severe psoriasis. Scarce evidence is available for DMF treatment in psoriatic patients at the time of COVID-19 pandemic. The objective of this study was to assess the long-term effectiveness and safety of DMF monotherapy in moderate-to-severe psoriasis during the COVID-19 pandemic period.

Methods

This multicenter, retrospective study included patients with moderate-to-severe psoriasis who had received a 48-week DMF treatment during the COVID-19 pandemic. Selected outcomes were: variation of mean PASI, proportion of patients achieving PASI50 and PASI75, variation of mean PGA and face PGA, genital PGA, scalp PGA, mean itch VAS and mean DLQI.

Results

Forty-four patients were enrolled, and four patients became COVID-19 positive during the observation period but did not discontinue DMF therapy. DMF produced a significant improvement of signs and symptoms of psoriasis as expressed by mean PASI variation from 13.07 at baseline to 6.11 at week 48 (p < 0.0001), itch VAS from 3.22 at baseline to 1.18 at week 48 (p < 0.001), PGA from 2.84 at baseline to 1.30 at week 48 (p < 0.0001) and DLQI from 13.09 at baseline to 6.07 at week 48 (p < 0.0001). The percentage of patients who achieved PASI50 and PASI75 was 4.55% at week 4 and 59.09% at week 48 and 0% at week 4 and 22.73% at week 48, respectively. A clinical important decrease of mean PGA score was observed in all subgroups, face psoriasis, genital psoriasis and scalp psoriasis. Adverse events were predictable and manageable.

Conclusions

DMF monotherapy is an effective and safe treatment option in moderate-to-severe psoriasis also in patients who develop SARS-CoV-2 infection.

Selective Tyrosine Kinase 2 Inhibition for Treatment of Inflammatory Bowel Disease: New Hope on the Rise

Conventional systemic and biologic agents are the mainstay of inflammatory bowel disease (IBD) management; however, many of these agents are associated with loss of clinical response, highlighting the need for effective, novel targeted therapies. Janus kinase (JAK) 1-3 and tyrosine kinase 2 (TYK2) mediate signal transduction events downstream of multiple cytokine receptors that regulate targeted gene transcription, including the interleukin-12, interleukin-23, and type I interferon receptors for TYK2. This review summarizes the role of TYK2 signaling in IBD pathogenesis, the differential selectivity of TYK2 inhibitors, and the potential clinical implications of TYK2 inhibition in IBD. A PubMed literature review was conducted to identify studies of JAK1-3 and TYK2 inhibitors in IBD and other immune-mediated inflammatory diseases. Key efficacy and safety information was extracted and summarized. Pan-JAK inhibitors provide inconsistent efficacy in patients with IBD and are associated with toxicities resulting from a lack of selectivity at therapeutic dosages. Selective inhibition of TYK2 signaling via an allosteric mechanism, with an agent that binds to the regulatory (pseudokinase) domain, may reduce potential toxicities typically associated with JAK1-3 inhibitors. Deucravacitinib, a novel, oral, selective TYK2 inhibitor, and brepocitinib and PF-06826647, TYK2 inhibitors that bind to the active site in the catalytic domain, are in development for IBD and other immune-mediated inflammatory diseases. Allosteric TYK2 inhibition is more selective than JAK1-3 inhibition and has the potential to limit toxicities typically associated with JAK1-3 inhibitors. Future studies will be important in establishing the role of selective, allosteric TYK2 inhibition in the management of IBD.

Plaque-type psoriasis inhibitors

Psoriasis is a common inflammatory skin disorder, which is mediated by the immune system and affects 1-4% of the world's population. Psoriasis is caused by a complex interaction between the immune system, autoantigens, psoriasis-associated genetic factors, and various environmental factors. As a chronic disease requiring long-term treatment, psoriasis is associated with follow-up costs and an economic burden on the patients, their families, and healthcare systems. The current treatments for moderate-to-severe plaque psoriasis include topical therapy, phototherapy, and systemic drugs consisting of biological/non-biological drugs. Within the past two decades, recent biological therapies for psoriasis have rapidly advanced. Moreover, new bispecific agents have the potential for better disease control, while small molecule drugs offer a future alternative to biological drugs and the more cost-effective, long-term treatment of the disease. The present study aimed to review updated data regarding the inhibitors used to improve plaque psoriasis that contain biologics, bispecific agents, small molecules, and aptamers (either approved or in the research phase).

Selectivity Profile of the Tyrosine Kinase 2 Inhibitor Deucravacitinib Compared with Janus Kinase 1/2/3 Inhibitors

INTRODUCTION

Deucravacitinib, a novel, oral, selective inhibitor of tyrosine kinase 2 (TYK2) signaling, acts via an allosteric mechanism by binding to the enzyme's regulatory domain instead of the catalytic domain. This unique binding provides high functional selectivity for TYK2 versus the closely related Janus kinases (JAKs) 1/2/3. Deucravacitinib was efficacious in phase 2 and 3 psoriasis trials, without clinical or laboratory parameters indicative of JAK 1/2/3 inhibition being observed. This analysis compared the kinase specificities of deucravacitinib versus JAK 1/2/3 inhibitors at therapeutic exposures.

METHODS

Signaling via JAK 1/3, JAK 2/2, and TYK2/JAK 2 dimers was measured in in vitro whole blood assays. Concentrations providing half-maximal inhibition (IC₅₀) in these assays were determined for deucravacitinib and the JAK 1/2/3 inhibitors tofacitinib, upadacitinib, and baricitinib. Newly derived whole blood IC₅₀ values were plotted against available pharmacokinetic profiles using doses evaluated in phase 2/3 trials. Simulated average daily inhibition and durations over which concentrations exceeded IC₅₀ were evaluated.

RESULTS

At clinically relevant exposures, projected steady-state deucravacitinib plasma concentrations were higher than TYK2 IC₅₀ for approximately 9-18 h. Maximal plasma concentrations (C_max) of deucravacitinib were 8- to 17-fold lower than JAK 1/3 IC₅₀ and > 48- to > 102-fold lower than JAK 2/2 IC₅₀. Simulated daily average TYK2 inhibition by deucravacitinib ranged from 50% to 69%. Simulations indicated that tofacitinib, upadacitinib, and baricitinib at steady state exhibited varying degrees of JAK 1/3 (daily average inhibition, 70-94%) and JAK 2/2 (23%-67%) inhibition at therapeutic concentrations, with C_max values 17- to 33-fold lower than their TYK2 IC₅₀ levels.

CONCLUSION

At clinically relevant doses and exposures, deucravacitinib demonstrates highly selective inhibition of TYK2 and not JAK 1/2/3. Tofacitinib, upadacitinib, and baricitinib variably inhibit JAK 1/2/3 but not TYK2. These results indicate that deucravacitinib is a distinct class of kinase inhibitor compared with JAK 1/2/3 inhibitors.

TYK2 as a therapeutic target in the treatment of autoimmune and inflammatory diseases

JAKs are intracellular protein tyrosine kinases that, through activation of STATs, are responsible for signal transduction pathways that regulate cellular responses to numerous cytokines, growth factors and hormones in many different cells. JAK-STAT signaling plays a key role in regulating immune function, and cytokines - such as IL-23, IL-12 and type I interferons - are central to the pathogenesis of autoimmune diseases, including psoriasis, inflammatory bowel disease and systemic lupus erythematosus. Here the authors review the evidence for targeting TYK2 as a more specific approach to treating these conditions. TYK2 inhibitors are clinically effective in autoimmune and inflammatory diseases and may avoid some of the complications reported with nonselective JAK inhibitors.

Retinoic acid-related orphan receptor gamma t (RORγt) inverse agonists/antagonists for the treatment of inflammatory diseases - where are we presently?

Introduction: The transcription factor retinoic acid-related orphan receptor gamma t (RORγt) has been identified as the master regulator of T_H17 cell differentiation and IL-17/22 production and is therefore an attractive target for the treatment of inflammatory diseases. Several orally or topically administered small molecule RORγt inverse agonists (RIAs) have progressed up to the end of clinical Phase 2.Areas covered: Based on publications and patent evaluations this review summarizes the evolution of the chemical matter for all 16 pharmaceutical companies, who develop(ed) a clinical-stage RIAs (until March 2021). Structure proposals for some clinical stage RIAs are presented and the outcome of the clinical trials is discussed.Expert opinion: So far, the clinical trials have been plagued with a high attrition rate. Main reasons were lack of efficacy (topical) or safety signals (oral) as well as, amongst other things, thymic lymphomas as seen with BMS-986251 in a preclinical study and liver enzyme elevations in humans with VTP-43742. Possibilities to mitigate these risks could be the use of RIAs with different chemical structures not interfering with thymocytes maturation and no livertox-inducing properties. With new frontrunners (e.g., ABBV-157 (cedirogant), BI 730357 or IMU-935) this is still an exciting time for this treatment approach.

Tyrosine kinase 2 and Janus kinase‒signal transducer and activator of transcription signaling and inhibition in plaque psoriasis

Plaque psoriasis is a common, chronic, systemic, immune-mediated inflammatory disease. The Janus kinase-signal transducer and activator of transcription pathway plays a major role in intracellular cytokine signaling in inflammatory processes involved in psoriasis. Although Janus kinase (JAK) 1-3 inhibitors have demonstrated efficacy in patients with moderate-to-severe psoriasis, safety concerns persist and no JAK inhibitor has received regulatory approval to treat psoriasis. Thus, an opportunity exists for novel oral therapies that are safe and efficacious in psoriasis. Tyrosine kinase 2 (TYK2) is a member of the JAK family of kinases and regulates signaling and functional responses downstream of the interleukin 12, interleukin 23, and type I interferon receptors. Deucravacitinib, which is an oral, selective inhibitor that binds to the regulatory domain of TYK2, and brepocitinib (PF-06700841) and PF-06826647, which are topical and oral TYK2 inhibitors, respectively, that bind to the active (adenosine triphosphate-binding) site in the catalytic domain, are in development for psoriasis. Selective, allosteric inhibition of TYK2 signaling may reduce the potential for toxicities associated with pan-JAK inhibitors. This article reviews Janus kinase-signal transducer and activator of transcription and TYK2 signaling and the efficacy and safety of JAK inhibitors in psoriasis to date, focusing specifically on TYK2 inhibitors.

Latest Advances for the Treatment of Chronic Plaque Psoriasis with Biologics and Oral Small Molecules

Psoriasis is a common immune-mediated chronic skin disease. Disease severity is influenced by several factors including the extent and localization of skin lesions, severity of pruritus and comorbidities, such as psoriatic arthritis. Moderate to severe psoriasis is defined when cutaneous involvement is diffuse, covering more than 10% of the body surface areas and/or involving the sensitive areas such as face, genitalia, folds or nails or has high impact on patients’ quality of life, and it occurs in approximately 15% of cases. In recent years, a growing understanding of psoriasis pathophysiology allowed the development of an increasing number of effective and safe treatments, including biologicals that are indicated for moderate to severe psoriasis. Different classes of biologicals have been already approved, including TNF-α (etanercept, infliximab, adalimumab and certolizumab pegol), IL-12/23 (ustekinumab), IL-17 (secukinumab, ixekizumab, brodalumab) and IL-23 (guselkumab, risankizumab, tildrakizumab) inhibitors. The objective of this narrative review is to revise efficacy and safety data of the latest biologicals, small oral molecules and biosimilar drugs for the treatment of chronic plaque psoriasis at Phase III of clinical development. The latest IL-17 and IL-23 inhibitors include bimekizumab, netakimab and mirikizumab as well as oral small molecules, such as deucravacitinib, a tyrosine kinase 2 selective inhibitor, and piclidenoson, an agonist of the Gi protein-associated A3 adenosine receptor. Additional molecules are in an early phase of development. Highly promising biologicals and small oral molecules are the leading edge of the systemic treatment of psoriasis.

Efficacy of dimethyl fumarate treatment for moderate-to-severe plaque psoriasis: presentation extracts from the 29th EADV virtual congress, 29-31 October 2020

Background: The 29th EADV Virtual Congress took place between the 29th-31st of October 2020. On October 29th, there was a Session on systemic treatment in which Professors Ulrich Mrowietz and Mar Llamas-Velasco presented the latest research on the efficacy of dimethyl fumarate (DMF) treatment for moderate-to-severe plaque psoriasis (BRIDGE and DIMESKIN 1 studies, respectively). The accepted DMF abstract from Professor Matthias Augustin, on the SKILL study, is also presented here. Results: Data from either prospective interventional (BRIDGE) or non-interventional (DIMESKIN 1, SKILL) studies among patients with moderate-to-severe psoriasis showed that DMF provides a positive efficacy profile in all four body regions included in the Psoriasis Area and Severity Index assessment (head and neck, trunk, upper and lower extremities) and a particularly interesting profile (strong efficacy) in the head and neck region. These findings may be of special interest to patients with scalp psoriasis who have been using topical therapies for a long time. Patient-reported outcomes (quality of life, pruritus) also improved during the 24 weeks of DMF treatment. The safety profile of DMF was similar to the previously described with fumaric acid esters. Conclusions: In summary, these results confirm the favorable efficacy and safety profile of DMF in long-term treatment.

Adenosine Signaling in Autoimmune Disorders

The molecular components of the purinergic system (i.e., receptors, metabolizing enzymes and membrane transporters) are widely expressed in the cells of the immune system. Additionally, high concentrations of adenosine are generated from the hydrolysis of ATP in any "danger" condition, when oxygen and energy availability dramatically drops. Therefore, adenosine acts as a retaliatory metabolite to counteract the nucleotide-mediated boost of the immune reaction. Based on this observation, it can be foreseen that the recruitment with selective agonists of the receptors involved in the immunomodulatory effect of adenosine might represent an innovative anti-inflammatory approach with potential exploitation in autoimmune disorders. Quite surprisingly, pro-inflammatory activity exerted by some adenosine receptors has been also identified, thus paving the way for the hypothesis that at least some autoimmune disorders may be caused by a derailment of adenosine signaling. In this review article, we provide a general overview of the roles played by adenosine on immune cells with a specific focus on the development of adenosine-based therapies for autoimmune disorders, as demonstrated by the exciting data from concluded and ongoing clinical trials.