From conventional to cutting edge: the new era of biologics in treatment of psoriasis

Molecular consideration relevant to the mechanism of the comorbidity between psoriasis and systemic lupus erythematosus (Review)

Systemic lupus erythematosus (SLE), a common autoimmune disease with a global incidence and newly diagnosed population estimated at 5.14 (range, 1.4-15.13) per 100,000 person-years and 0.40 million people annually, respectively, affects multiple tissues and organs; for example, skin, blood system, heart and kidneys. Accumulating data has also demonstrated that psoriasis (PS) can be a systemic inflammatory disease, which can affect organs other than the skin and occur alongside other autoimmune diseases, such as inflammatory bowel disease, multiple sclerosis, rheumatoid arthritis and SLE. The current explanations for the possible comorbidity of PS and SLE include: i) The two diseases share susceptible gene loci; ii) they share a common IL-23/T helper 17 (Th17) axis inflammatory pathway; and iii) the immunopathogenesis of the two conditions is a consequence of the interactions between IL-17 cytokines with effector Th17 cells, T regulatory cells, as well as B cells. In addition, the therapeutic efficacy of IL-17 or TNF-α inhibitors has been demonstrated in PS, and has also become evident in SLE. However, the mechanisms have not been investigated. To the best of our knowledge, there remains a lack of substantial studies on the correlation between PS and SLE. In the present review, the literature, with regards to the epidemiology, genetic predisposition, inflammatory mechanisms and treatment of the patients with both PS and SLE, has been reviewed. Further investigations into the molecular pathogenic mechanism may provide drug targets that could benefit the patients with concomitant PS and SLE.

Current and emerging prospects in the psoriatic treatment

Psoriasis is an autoimmune chronic disorder that causes inflammation and a scaly epidermis. The exact pathogenesis of the disease is not known yet. According to the studies, psoriasis is considered an immune-mediated disease. Until now it is believed that genetic and environmental factors are responsible for the disease. There are many comorbidities associated with psoriasis which increases difficulties as patients in some cases get addicted to drugs, alcohol, and smoking which reduces their quality of life. The patient may face social ignorance or suicidal thoughts which may arise in the patient's mind. Due to the undefined trigger of the disease, the treatment is not fully established but by considering the severe impact of the disease researchers are focusing on novel approaches for successful treatment. which has succeeded to a large extent. Here we review pathogenesis, problems faced by psoriatic patients, the need for the development of new treatments over conventional therapies, and the history of psoriatic treatments. We thoroughly focus on emerging treatments like biologics, biosimilars, and small molecules which are now showing more efficacy and safety than conventional treatments. Also, this review article discusses novel approaches which are now in research such as drug repurposing, treatment by stimulation of the vagus nerve, regulation of microbiota, and autophagy for improving disease conditions.

Perspective insights of small molecules, phytoconstituents and biologics in the management of psoriasis: A focus on targeting major inflammatory cytokine pathways

Psoriasis is an enduring, pruritic and papulosquamous skin ailment that poses a significant burden on public health. It is mainly characterized by hyperkeratosis, acanthosis, parakeratosis, scaly and erythematous plaques. Biomarkers like interleukin-17, interleukin-12 and -23 and tumor necrosis factor-α serve as key drivers of psoriatic pathogenesis. Triggered release of pro-inflammatory cytokines from various up-regulated pathways leads to psoriatic inflammation. Several target moieties like biologics, small molecules and herbal moieties play a fundamental role in the repression of pathogenesis of psoriasis. Biologics and small molecules engaged in the management of psoriasis have been emphasized in detail. An insight into nano-carrier interventions on herbal moieties and clinical aspects of psoriasis are also highlighted. This review emphasizes various pathological targets involved in psoriasis.

Keratin 6, 16 and 17-Critical Barrier Alarmin Molecules in Skin Wounds and Psoriasis

Located at the skin surface, keratinocytes (KCs) are constantly exposed to external stimuli and are the first responders to invading pathogens and injury. Upon skin injury, activated KCs secrete an array of alarmin molecules, providing a rapid and specific innate immune response against danger signals. However, dysregulation of the innate immune response of KCs may lead to uncontrolled inflammation and psoriasis pathogenesis. Keratins (KRT) are the major structural intermediate filament proteins in KCs and are expressed in a highly specific pattern at different differentiation stages of KCs. While KRT14-KRT5 is restricted to basal proliferative KCs, and KRT10-KRT1 is restricted to suprabasal differentiated KCs in normal skin epidermis, the wound proximal KCs downregulate KRT10-K1 and upregulate KRT16/KRT17-KRT6 upon skin injury. Recent studies have recognized KRT6/16/17 as key early barrier alarmins and upregulation of these keratins alters proliferation, cell adhesion, migration and inflammatory features of KCs, contributing to hyperproliferation and innate immune activation of KCs in response to an epidermal barrier breach, followed by the autoimmune activation of T cells that drives psoriasis. Here, we have reviewed how keratins are dysregulated during skin injury, their roles in wound repairs and in initiating the innate immune system and the subsequent autoimmune amplification that arises in psoriasis.

Type1 Interferons Potential Initiating Factors Linking Skin Wounds With Psoriasis Pathogenesis

Psoriasis is a chronic autoimmune skin disease that can often be triggered upon skin injury, known as Koebner phenomenon. Type 1 interferons (IFNα and IFNβ), key cytokines that activate autoimmunity during viral infection, have been suggested to play an indispensable role in initiating psoriasis during skin injury. Type 1 IFN-inducible gene signature has been identified as one of the major upregulated gene signatures in psoriatic skin. Type 1 IFNs treatments often directly induce or exacerbate psoriasis, whereas blocking type 1 IFNs signaling pathway in animal models effectively inhibits the development of T cell-mediated skin inflammation and psoriasis-like inflammatory diseases. Epidermal keratinocytes (KCs) occupy the outermost position in the skin and are the first responder to skin injury. Skin injury rapidly induces IFNβ from KCs and IFNα from dermal plasmacytoid dendritic cells (pDCs) through distinct mechanisms. Host antimicrobial peptide LL37 potentiates double-stranded RNA (dsRNA) immune pathways in keratinocytes and single-stranded RNA or DNA pathways in pDCs, leading to production of distinct type 1 IFN genes. IFNβ from KC promotes dendritic cell maturation and the subsequent T cell proliferation, contributing to autoimmune activation during skin injury and psoriasis pathogenesis. Accumulating evidences have indicated an important role of this dsRNA immune pathway in psoriasis pathogenesis. Together, this review describes how skin injury induces type 1 IFNs from skin cells and how this may initiate autoimmune cascades that trigger psoriasis. Targeting keratinocytes or type 1 IFNs in combination with T cell therapy may result in more sustainable effect to treat auto-inflammatory skin diseases such as psoriasis.

HLA-C*06:02 Does Not Predispose to Clinical Response Following Long-Term Adalimumab Treatment in Psoriatic Patients: A Retrospective Cohort Study

BACKGROUND

The genetic basis of predisposition to psoriasis is recognised; however, the response to psoriasis treatment in patients with different genetic predisposition is poorly understood.

OBJECTIVE

To analyse the presence of the HLA-C*06:02 polymorphism in psoriatic patients treated with adalimumab.

METHODS

Genomic DNA was extracted from whole blood of 122 patients with moderate-to-severe psoriasis treated with adalimumab for 3 years. Genotyping was performed using PCR. Disease severity was assessed by the Psoriasis Area and Severity Index (PASI) at day 0 and after 1, 3, 6, 12, 24 and 36 months. Logistic regression was used to evaluate the association between dependent variables (including HLA-C*06:02 status) and achievement of PASI 50, 75 and 90.

RESULTS

No difference was observed after adalimumab treatment between C*06:02 positive (HLA-C*06:02-POS) patients (n = 46) and C*06:02 negative (HLA-C*06:02-NEG) patients (n = 76) over the 3-year follow-up period in terms of PASI response or time-course when PASI response was achieved. However, a small, but non-statistically significant difference was noted between genotypes for PASI 50 at 1 month (HLA-C*06:02-NEG: 44.7% vs. HLA-C*06:02-POS: 56.5%) and at 3 months (HLA-C*06:02-NEG: 71.1% vs. HLA-C*06:02-POS: 80.4%). Simple logistic regression analysis did not reveal an association between independent variables (including C*06:02 status) and PASI response; however, multivariate regression revealed that gender (females better than males) was associated with achievement of PASI 50 at month 1 (OR 0.34, 95% CI 0.16-0.72, p = 0.005) and of PASI 75 at 3 months (OR 0.36, 95% CI 0.16-0.8, p = 0.012).

CONCLUSION

Adalimumab reduced long-term severity in patients with moderate-severe psoriasis, independent of their HLA-C*06:02 status.

Tumor Necrosis Factor and Lymphotoxin in Regulation of Intestinal Inflammation

Ulcerative colitis and Crohn's disease are the major forms of inflammatory bowel disease. Cytokines of the tumor necrosis factor (TNF) family play an important role in the regulation of intestinal inflammation. In this review, we discuss the function of key cytokines of this family - TNF and lymphotoxin (LT) - in mucosal healing, IgA production, and in control of innate lymphoid cells (ILCs), novel regulators of mucosal homeostasis in the gut. TNF plays a central role in the pathogenesis of inflammatory bowel diseases (IBD). LT regulates group 3 of ILCs and IL-22 production and protects the epithelium against damage by chemicals and mucosal bacterial pathogens. In addition, we discuss major mouse models employed to study the mechanism of intestinal inflammation, their advantages and limitations, as well as application of TNF blockers in the therapy for IBD.

Treatment of psoriasis and psoriatic arthritis

Skin and joint manifestations associated with psoriasis and psoriatic arthritis (PsA) can significantly impact a patient's quality of life. Successful treatment is imperative in order to improve signs and symptoms of the disease, and to alleviate physical or psychological distress. For patients with mild psoriasis with or without PsA, topical agents and targeted phototherapy are appropriate treatments for psoriasis. Systemic therapies, such as methotrexate and phototherapy are recommended options for patients with more severe psoriasis, but their long-term use is hindered by safety concerns. Advancements in understanding the pathogenesis of psoriasis, including the role of T cells and cytokines, have been crucial to the development of biological therapies. These target the immune system and are suitable options for patients with extensive disease. Biological therapies for the treatment of psoriasis include targeted therapies (alefacept) and anti-cytokine therapies (anti-tumour necrosis factor [TNF] therapies [adalimumab, etanercept, infliximab] and a monoclonal antibody against interleukin [IL]-12 and IL-23 [ustekinumab]). Patients with PsA should be treated appropriately in order to improve symptoms and inhibit structural joint damage. Non-steroidal anti-inflammatory drugs or local intra-articular injections of corticosteroids can be used successfully in patients with mild PsA; however, neither treatment prevents the development of structural joint damage. For patients with moderate to severely active PsA, disease-modifying antirheumatic drugs (such as methotrexate), TNF inhibitor treatments (adalimumab, etanercept, infliximab and golimumab) or their combination are considered first-line treatment. This review provides a brief overview of treatment options for psoriasis and PsA, with an emphasis on the efficacy and safety of anti-TNF therapies.

Pharmacogenetics of psoriasis: HLA-Cw6 but not LCE3B/3C deletion nor TNFAIP3 polymorphism predisposes to clinical response to interleukin 12/23 blocker ustekinumab

BACKGROUND

Our understanding of the genetic basis of predisposition to psoriasis is increasing exponentially due to the progress of genetic studies. However, so far little is known about genetic predisposition in relation to the response to psoriasis treatments. Recent data identified genetic predictors for the clinical outcome of conventional treatments such as methotrexate, acitretin and vitamin D derivatives, but few studies are available on genetic predictors of response to biologics. We hypothesized that genetic variations associated with increased risk of developing psoriasis may also act as predictors for the outcome of biologic therapy.

OBJECTIVES

The aim of our study was to analyse the presence of three different psoriasis susceptibility genetic variations (HLA-Cw6; TNFAIP3 rs610604 polymorphism; LCE3B/3C gene deletions) in a cohort of patients affected by moderate to severe psoriasis under ustekinumab treatment. Our primary endpoint was to evaluate the association between Psoriasis Area and Severity Index (PASI) 75 response at week 12 and HLA-Cw6 status.

METHODS

Fifty-one patients were genotyped by standard methods and psoriasis severity (PASI score) was evaluated at day 0 and after 4, 12, 24 and 40 weeks of treatment.

RESULTS

We observed increased response to ustekinumab in Cw6-positive (Cw6POS) patients [PASI 75 at week 12: 96·4% in Cw6POS vs. 65·2% in Cw6-negative (Cw6NEG) patients; P = 0·008]. In addition, we show that HLA-Cw6POS patients responded faster to ustekinumab, 89·3% of them reaching PASI 50 at week 4, after a single injection (vs. 60·9% of HLA-Cw6NEG patients). The superior response of HLA-Cw6POS patients was maintained throughout the study period, reaching the highest statistical significance for PASI 75 at week 28 (96·35% Cw6POS vs. 72·7% Cw6NEG; odds ratio 9·8). Analysis of TNFAIP3 rs610604 polymorphism and LCE3B/3C gene deletions did not show any significant association with response to ustekinumab.

CONCLUSIONS

Our observations underline the role of HLA-Cw6 not only as a psoriasis susceptibility gene, but also as a pharmacogenetic marker of response to ustekinumab in psoriasis.

Dermatological adverse reactions during anti-TNF treatments: focus on inflammatory bowel disease

The clinical introduction of tumour necrosis factor (TNF) inhibitors has deeply changed the treatment of inflammatory bowel diseases (IBD). It has demonstrated impressive efficacy as compared to alternative treatments, allowing for the chance to achieve near-remission and long-term improvement in function and quality of life and to alter the natural history of Crohn's disease (CD) and ulcerative colitis (UC). As a consequence of longer follow-up periods the number of side effects which may be attributed to treatment with biologics is growing significantly. Cutaneous reactions are among the most common adverse reactions. These complications include injection site reactions, cutaneous infections, immune-mediated complications such as psoriasis and lupus-like syndrome and rarely skin cancers. We review the recent literature and draw attention to dermatological side effects of anti-TNF therapy of inflammatory bowel disease.

New era of biologic therapeutics in atopic dermatitis

INTRODUCTION

Atopic dermatitis (AD) is a common inflammatory skin disease regulated by genetic and environmental factors. Both skin barrier defects and aberrant immune responses are believed to drive cutaneous inflammation in AD. Existing therapies rely largely on allergen avoidance, emollients and topical and systemic immune-suppressants, some with significant toxicity and transient efficacy; no specific targeted therapies are in clinical use today. As our specific understanding of the immune and molecular pathways that cause different subsets of AD increases, a variety of experimental agents, particularly biologic agents that target pathogenic molecules bring the promise of safe and effective therapeutics for long-term use.

AREAS COVERED

This paper discusses the molecular pathways characterizing AD, the contributions of barrier and immune abnormalities to its pathogenesis, and development of new treatments that target key molecules in these pathways. In this review, we will discuss a variety of biologic therapies that are in development or in clinical trials for AD, perhaps revolutionizing treatment of this disease.

EXPERT OPINION

Biologic agents in moderate to severe AD offer promise for controlling a disease that currently lacks good and safe therapeutics posing a large unmet need. Unfortunately, existing treatments for AD aim to decrease cutaneous inflammation, but are not specific for the pathways driving this disease. An increasing understanding of the immune mechanisms underlying AD brings the promise of narrow targeted therapies as has occurred for psoriasis, another inflammatory skin disease, for which specific biologic agents have been demonstrated to both control the disease and prevent occurrence of new skin lesions. Although no biologic is yet approved for AD, these are exciting times for active therapeutic development in AD that might lead to revolutionary therapeutics for this disease.

Sun exposure rapidly reduces plasmacytoid dendritic cells and inflammatory dermal dendritic cells in psoriatic skin

BACKGROUND

Interferon (IFN)-α-producing plasmacytoid dendritic cells (pDCs), inflammatory CD11c+CD1c- myeloid dendritic cells (mDCs) and macrophages have been found to contribute to the pathogenesis of psoriasis. Heliotherapy is a well-established treatment modality of this disease, although the details of how the effects are mediated are unknown.

OBJECTIVES

To test the hypothesis that exposure to natural sun affects pathogenic DC subsets in lesional skin.

METHODS

Skin biopsies were obtained from lesional and nonlesional skin in 10 patients with moderate to severe psoriasis subjected to controlled sun exposure on Gran Canaria. Biopsies were obtained at baseline, day 2 and day 16 and examined by immunohistochemistry.

RESULTS

Sixteen days of heliotherapy had excellent clinical effect on patients with psoriasis, with significant reductions in Psoriasis Area and Severity Index (PASI) scores. In lesional skin pDC numbers and expression of MxA, a surrogate marker for IFN-α, were rapidly reduced. Inflammatory CD11c+CD1c- mDCs were significantly reduced whereas resident dermal CD11c+CD1c+ mDCs were unaffected. Expression levels of the maturation marker DC-LAMP (CD208) on mDCs were significantly reduced after sun exposure, as were the numbers of lesional dermal macrophages. A decrease of dermal DC subsets and macrophages was already observed after 1 day of sun exposure. An additional finding was that DC-SIGN (CD209) is primarily expressed on CD163+ macrophages and not DCs.

CONCLUSIONS

The clinical improvement in psoriasis following sun exposure is associated with rapid changes in dermal DC populations and macrophages in lesional skin, preceding the clinical effect. These findings support the concept that these DC subsets are involved in the pathogenesis of psoriasis and suggest that sun-induced clinical benefit may partly be explained by its effect on dermal DCs.

[Treatment of psoriasis using biologics]

Psoriasis is a chronic inflammatory skin disease, which is characterized by red, scaly, raised plaques. Its symptoms may range in severity and there are severe clinical subtypes of psoriasis including pustular psoriasis. Pre-biological systemic therapies were targeting mainly keratinocyte proliferation and T cell activation. However, there were cases, in which these classic therapies were not fully effective or could not be used because of the accompanied severe organ failure of the psoriasis patient. Recent progress in psoriasis research has clarified which of the cells, cell surface molecules and cytokines play a pivotal role in the pathogenesis of psoriasis. Biological systemic therapies targeting these molecules have turned out to be extremely effective in treating psoriasis and are now used to treat moderate to severe psoriasis worldwide. These biological therapies are not only more effective than pre-biological systemic therapies, but also show more rapid response, and long-term efficacy is expected. The TNF-alpha inhibitors are now approved as the first biological therapy for psoriasis in Japan. These TNF-alpha inhibitors are expected to be a new standard therapy for severe psoriasis, however, since the long-term safety is an unsolved issue, careful clinical monitoring is required. (193 words).

Drug-Induced Lichenoid Dermatitis with Histopathologic Features of Mycosis Fungoides in a Patient with Psoriasis

Background:

With recent advancements in the understanding of psoriasis, treatment has evolved toward more targeted therapy in the form of biologics. Although generally safe and well tolerated, various adverse reactions may occur with the use of biologics.

Objectives:

The objective of this article is to present a case of a biologic-induced drug eruption initially presenting with histopathologic features of mycosis fungoides (MF).

Methods and Results:

A 47-year-old male presented with an extensive erythematous macular eruption approximately 14 hours after a single dose of etanercept. Histopathology initially revealed a lichenoid dermatitis with features of MF, but immunohistopathology later refuted the presence of MF.

Conclusions:

It is important for clinicians to be aware that adverse cutaneous reactions with biologic therapy may initially present with histopathologic features of MF.

Long-term use of adalimumab in the treatment of moderate to severe plaque psoriasis: a review of the literature

Psoriasis is a chronic T-cell-mediated inflammatory disease that primarily affects the skin and joints. Patients with moderate to severe psoriasis constitute about 30% of the psoriasis population. Treatment of this group is challenging due to the long-term side effects, toxicities and inconvenience of conventional treatments such as phototherapy, methotrexate and cyclosporine. However, recent advances in our understanding of the pathogenesis of psoriasis have led to the popular use of biologics, which offer a safer, more convenient and effective targeted therapy. Adalimumab was originally approved for treating rheumatoid arthritis. Currently, adalimumab is also approved for treatment of adult patients with moderate to severe chronic plaque psoriasis who are candidates for systemic therapy or phototherapy or when other systemic therapies are medically less appropriate. Since the onset of the use of biologics, there have been concerns over safety and efficacy when used as long-term therapy. This paper reviews all publications, posters and abstracts reporting original data on the efficacy and/or safety of adalimumab in patients treated for chronic plaque psoriasis for more than 1 year.

Recent developments in the treatment of uveitis: an update

The management of complex uveitis is often based around the use of oral corticosteroids. To spare the side effects of corticosteroids, second-line oral immunosuppressant drugs are used. Newer systemic immunosuppressive drugs, including biologics, and locally delivered treatments are being evaluated. This article reviews current conventional treatments, discusses their limitations and evaluates newer treatment strategies. Current theories about the pathogenesis of uveitis and potential targets for treatment are discussed in this context. We are still in search of a low-risk, where possible, locally delivered and targeted treatment for uveitis.

[Long term treatment of psoriasis with TNF-alpha antagonists. Occurrence of malignant melanoma]

A 51-year-old white man developed de novo a cutaneous malignant melanoma (Stage Ia) after a 30-month treatment period with TNF-alpha-antagonists, consecutively using infliximab, adalimumab and etanercept because of a recalcitrant moderate to severe plaque psoriasis. The patient previously had been treated fumarates for 4 years, cyclosporine A for 2 months and methotrexate for 5 weeks. He also received cycles of cream PUVA and UVB before and then between systemic medications. A possible causal connection between development of melanoma and immunosuppressive treatment is discussed in the light of recent literature. The termination of TNF-alpha-antagonist therapy following development of melanoma is recommended.

Dermatology for the general surgeon

Preparation of the patient with preexisting skin disease for surgery can be challenging. In addition to encountering the skin with nearly every procedure, the surgeon will also likely experience skin-related conundrums, concerns, and associated conditions in the preoperative, perioperative, or postoperative periods. These concerns are reviewed using best available evidence.

Review article: anti TNF-alpha induced psoriasis in patients with inflammatory bowel disease

BACKGROUND

Anti TNF-alpha agents are used successfully for several autoimmune diseases, including IBD and psoriasis. An emerging challenge is the increasing incidence of anti TNF-alpha induced psoriasis. A total of 120 cases have been currently reported, of whom 18 patients were treated with biological agents for IBD.

OBJECTIVES

To analyse all cases of anti TNF-alpha induced psoriasis in patients with IBD in the literature and to investigate potential mechanisms of action.

METHODS

A literature review was performed in the PubMed, Medline, Cochrane and EMBASE databases, with simple analysis of demographic data, drug administration and psoriasis onset. Risk and incidence patient/year/duration (pyd) was calculated.

RESULTS

A total of 18 patients with IBD treated by anti TNF-alpha agents developed drug-induced psoriasis of which, 17 patients developed with infliximab, one with adalimumab. The most frequent time of onset is between 3rd and 4th infusion of infliximab. Withdrawal of infliximab led to regression of lesions in 16 patients. In six patients, infliximab was reintroduced with no further recurrence of psoriasis.

CONCLUSIONS

Although anti TNF-alpha induced psoriasis is extremely rare, understanding the mechanism will be a key step towards better realizing the role played by TNF-alpha and its pharmacological inhibitors in immune-mediated diseases.

Discovery and structure-activity study of a novel benzoxaborole anti-inflammatory agent (AN2728) for the potential topical treatment of psoriasis and atopic dermatitis

A series of phenoxy benzoxaboroles were synthesized and screened for their inhibitory activity against PDE4 and cytokine release. 5-(4-Cyanophenoxy)-2,3-dihydro-1-hydroxy-2,1-benzoxaborole (AN2728) showed potent activity both in vitro and in vivo. This compound is now in clinical development for the topical treatment of psoriasis and being pursued for the topical treatment of atopic dermatitis.