The immunologic basis for the treatment of psoriasis with new biologic agents

Clinical Efficacy of Efalizumab in Patients with Chronic Plaque Psoriasis: Results from Three Randomized Placebo-Controlled Phase III Trials: Part I

Background:

Effective psoriasis therapies are needed for long-term symptom control. ObjectiveAssess efalizumab (Raptiva®) efficacy in a large cohort of psoriasis patients.

Methods:

Data from three Phase III, randomized, double-blind, parallel-group, placebo-controlled, multicenter studies were pooled. Patients ( n = 1,651) with moderate to severe plaque psoriasis received 12 weeks of subcutaneous efalizumab 1 or 2 mg/kg/wk or placebo.

Remits:

All efficacy measures reached statistical significance within each of the individual studies ( p < 0.001) and overall. More efalizumab-treated patients achieved > 75% and ≥ 50% Psoriasis Area and Severity Index (PASI) improvement at week 12 than did placebo-treated patients (27.8% vs 3.8% [ p < 0.001] and 56.1% vs 14.6% [ p < 0.001], respectively). Significant PASI improvements occurred as early as week 2 (12.5% vs 7.9%, p =0.0001). Adverse events were generally mild to moderate.

Conclusion:

Efalizumab resulted in early and significant improvement for all efficacy endpoints and was well tolerated in patients with moderate to severe chronic plaque psoriasis.

XP-828L in the Treatment of Mild to Moderate Psoriasis: Randomized, Double-Blind, Placebo-Controlled Study

Background:

XP-828L, a protein extract obtained from sweet whey, has demonstrated potential benefit for the treatment of mild to moderate psoriasis in an open-label study.

Objective:

To study in a randomized, double-blind, placebo-controlled study the safety and efficacy of XP-828L in the treatment of mild to moderate psoriasis.

Design:

XP-828L 5 g/d (group A, n = 42) or placebo (group B, n = 42) was given orally for 56 days followed by XP-828L 5 g/d in group A and by XP-828L 10 g/d in group B for an additional 56 days.

Results:

Patients receiving XP-828L 5 g/d for 56 days had an improved Physician's Global Assessment (PGA) score compared with patients under placebo ( p < .05). Considering the data of group A only, the PGA score improved from day 1 to day 56 ( p < .01); the Psoriasis Area and Severity Index score improved as well, but to a lesser extent ( p < .05).

Conclusion:

Oral administration of 5 g/d XP-828L compared with a placebo significantly improved the PGA score of patients with mild to moderate psoriasis.

Biologic Therapeutics in the Treatment of Psoriasis. Part 1: Review

Background:

Psoriasis is a chronic inflammatory skin disease principally mediated by activated T cells, which release proinflammatory cytokines with reactive epidermal changes in the skin, producing the characteristic lesions of psoriasis. New research into possible treatment options has been inspired by increased understanding of the pathophysiology of psoriasis and advances in immunology and molecular biology permitting the development of targeted, highly active biologic agents.

Objective:

The aim of this article is to review the efficacy and safety of five biologic therapeutics in the treatment of moderate to severe psoriasis and to provide practical guidelines for integration of these agents in the management of psoriasis.

Methods:

We searched MEDLINE (1966–2005) for articles containing the key words: alefacept, efalizumab, etanercept, infliximab, and adalimumab and searched recent conference abstracts.

Results:

Emerging immunotherapeutic agents (fusion proteins, recombinant cytokines, fusion toxins, or antibodies) target T cells or cytokines responsible for plaque formation that is characteristic of psoriasis. Alefacept is the first biologic to be approved in both the United States and Canada. More recently, efalizumab and etanercept and infliximab have been approved in the United States and Canada for plaque-type psoriasis. Adalimumab is currently in phase III clinical trials.

Conclusion:

These novel biologics offer an intriguing and effective treatment option for patients with moderate to severe psoriasis.

Efalizumab in the Treatment of Psoriasis

Background:

Efalizumab (anti-CD11a), a targeted, reversible T-cell modulator, is a humanized monoclonal antibody that provides a rapid onset of action of clinical benefit and has been studied up to 36 months, showing continuous control of plaque-type psoriasis. Efalizumab has recently been approved in Canada for this indication.

Objective:

To examine the efficacy and safety of efalizumab by presenting the latest data in the treatment of psoriasis.

Methods:

We searched MEDLINE (1966–2005) for randomized, double-blind studies of efalizumab (1 mg/kg for 12 weeks) using the following key words: psoriasis, efalizumab, biologics, and treatment.

Results:

It was found that the proportion of patients who achieved Psoriasis Area and Severity Index (PASI) 75 and PASI 50 ranged from 22 to 39% and 52 to 61%, respectively. PASI 75 improvement was achieved in 44% of patients, who continued to receive efalizumab by week 24. Following 36 months of continuous treatment, a PASI 75 response was achieved by 45% (intent-to-treat [ITT] analysis), 59% (maintenance group analysis), and 73% (as-treated analysis). Its safety profile was similar during the 12-week and 36-month treatment periods.

Conclusions:

Currently, more than 3,500 patients have received efalizumab in clinical trials. Efalizumab may be an important treatment option for dermatologists seeking to provide a well-tolerated and effective treatment modality for patients with moderate to severe chronic plaque psoriasis.

Efficacy Outcomes in Patients Using Alefacept in the AWARE Study

Background:

Alefacept has demonstrated efficacy in clinical trials of patients with chronic plaque psoriasis, either as monotherapy or combined with other treatment modalities such as phototherapy.

Objective:

AWARE (Amevive Wisdom Acquired from Real-World Evidence) is a multicenter, observational, phase IV Canadian registry of psoriasis patients treated with alefacept.

Methods:

Patients with chronic plaque psoriasis were treated with at least one course of alefacept, either alone or added on to their existing antipsoriatic treatment regimen. Each course of alefacept was followed by a period of at least 12 weeks off treatment. Efficacy outcomes included physicians' and patients' assessments of response at week 18, as well as change in percent body surface area (BSA) involvement with psoriasis. The time to retreatment was assessed in patients receiving a second course of alefacept during at least 60 weeks of prospective follow-up.

Results:

The majority of patients received alefacept in combination with other antipsoriatic therapies. Physicians' and patients' assessments of response at 18 weeks showed that 42% and 41% of patients, respectively, had a “cleared to marked response” and a further 42% had a “moderate to some response.” Among those patients whose psoriasis was moderately controlled or not controlled at baseline, 49 to 51% and 33 to 36%, respectively, improved to “cleared to marked response” at 18 weeks. A substantial shift in percent BSA involvement with psoriasis was observed at 18 weeks, with 55% of patients having a BSA involvement of < 10% at week 18 compared to only 20% having this level of BSA involvement at baseline. The mean time to retreatment among the 60% of patients who received a second course of alefacept was 19.3 weeks (range 2–47 weeks).

Conclusion:

A single course of alefacept therapy improved outcomes in this broad population of real-world chronic plaque psoriasis patients.

Study Limitations:

The limitations of this study include its nonrandomized, noncontrolled, noncomparative design, which allowed multiple different treatment approaches across all patients. The rating scales used in this study have not been previously validated, and ranges were assigned to baseline control and response data that are not specifically defined. Clinicians did not receive specific training in using these scales; therefore, interrater variability could not be assessed.

Efficacy of narrowband ultraviolet B phototherapy and levels of serum vitamin D3 in psoriasis: A prospective study

INTRODUCTION

Narrowband ultraviolet B phototherapy (NBUVB) is safe and effective treatment for psoriasis. Vitamin D plays an important role in pathogenesis of psoriasis. It is known that psoriasis patients have low serum 25(OH)D levels, which increase after NBUVB. We assessed serum 25(OH)D levels, its correlation with Psoriasis Area and Severity Index (PASI), and the effect of NBUVB on 25(OH)D levels among Indian psoriasis patients.

MATERIALS AND METHODS

A prospective study comprising 30 adults with psoriasis with no major comorbidities (PASI > 10 and off-therapy >4 weeks) was conducted. PASI was estimated at baseline among patients and repeated after receiving 12 weeks of NBUVB therapy. Thirty age and gender-matched healthy controls were recruited to compare 25(OH)D levels at baseline and at 12 weeks. Patient demographic parameters, treatment dose, duration, side effects, and its impact on 25(OH)D levels and PASI were serially evaluated.

RESULTS

A total of 30 patients presenting with psoriasis and 30 healthy controls were enrolled in the study. Mean baseline PASI (M: F =19:11) among patients with mean age 36.8 (±7.7) years was 20.5 (±6.3) and all patients were either 25(OH)D deficient (n = 14) or insufficient (n = 16). Their baseline 25(OH)D levels were significantly lower than controls (25.93 nmol/L vs 47.54 nmol/L; P < 0.001). After NBUVB therapy (average cumulative dose 20.76 ± 7.1 J/cm(2); average treatment sessions 32.57 ± 1.9), there was a significant improvement in PASI as well as 25(OH)D (P < 0.05). There was no correlation between the mean improvement in PASI and 25(OH)D after 12 weeks of therapy. Twelve (40%) patients had therapy-related side effects [pruritus (n = 8), erythema (n = 4)], none had major side effects.

CONCLUSION

Improvement in PASI and serum 25(OH)D levels after NBUVB in psoriasis is significant but poorly correlated with each other. Vitamin D may not be the lone mediator of the therapeutic effects of NBUVB on psoriasis.

Anti-TNF agents for paediatric psoriasis

BACKGROUND

Psoriasis is a chronic skin disease that may develop at any age. Estimates for the United States and Europe suggest that psoriasis accounts for 4% of skin diseases in children. In most cases, the condition is mild and can be treated with creams. However, a small percentage of children have moderate to severe disease that requires drugs, such as ciclosporin or methotrexate, and some will require injections with newer biological agents, such as anti-TNF (tumour necrosis factor) drugs. Anti-TNF drugs (among them etanercept, infliximab, and adalimumab) are designed to reduce inflammation in the body caused by tumour necrosis factor. Evidence for the safety and efficacy of these biological agents in paediatric psoriasis is lacking.

OBJECTIVES

To assess the efficacy and safety of anti-TNF agents for the treatment of paediatric psoriasis.

SEARCH METHODS

We searched the following databases up to July 2015: the Cochrane Skin Group Specialised Register, the Cochrane Central Register of Controlled Trials (CENTRAL; 2015, Issue 6), MEDLINE (from 1946), Embase (from 1974), and LILACS (from 1982). We also searched 13 trials registers and checked the reference lists of included studies and key review articles for further references to relevant randomised controlled trials (RCTs). We handsearched conference proceedings and attempted to contact trial authors and relevant pharmaceutical manufacturers. We searched the US Food and Drug Administration's and European Medicines Agency's adverse effects databases.

SELECTION CRITERIA

All relevant RCTs that evaluated the efficacy and safety of anti-TNF agents for the treatment of chronic plaque psoriasis in individuals less than 18 years of age.

DATA COLLECTION AND ANALYSIS

Two review authors independently checked titles and abstracts and performed data extraction and 'Risk of bias' assessment of the included studies. One review author entered data into Review Manager (RevMan), and a second review author checked the data. We also attempted to obtain unclear data from the trial authors where possible.Our primary outcomes were investigator-assessed number of participants achieving a 75% improvement in Psoriasis Area and Severity Index-75 (PASI 75) compared to baseline, improvement in quality of life using an instrument such as Children's Dermatology Life Quality Index (CDLQI), and adverse effects. Our secondary outcomes included the proportion of participants achieving PASI 50 and the Physician's Global Assessment (PGA).

MAIN RESULTS

We included one study with 211 participants (median age 13 years), in which etanercept (dosage ranged from 0.8 to 50 mg per kilogram of body weight) was compared to placebo. Follow-up was over a 48-week period.At week 12, 57% versus 11% who received etanercept or placebo, respectively, achieved the PASI 75 (risk ratio 4.95, 95% confidence interval (CI) 2.83 to 8.65; high-quality evidence). Absolute risk reduction and the number needed to treat to obtain a benefit with etanercept was 45% (95% CI 33.95 to 56.40) and 2 (95% CI 1.77 to 2.95), respectively.The percentage improvement from baseline of the CDLQI scores at week 12 was better in the etanercept group than the placebo group (52.3% versus 17.5%, respectively (P = 0.0001)). Analysis between the groups showed an effect size that was clinically important (mean difference 2.30, 95% CI 0.85 to 3.75; high-quality evidence). However, means, medians, and minimal important difference results and results of the Pediatric Quality of Life Inventory, Stein Impact on Family Scale, and Harter Self-Perception Profile for Children scores must be interpreted with caution, as they were not prespecified outcomes.Three serious adverse events were reported, but they were resolved without sequelae. Deaths or other events such as malignant tumours, opportunistic infections, tuberculosis, or demyelination were not reported in the included study.Also, 13% of participants in the placebo group and 53% in the etanercept group had a PGA of clear or almost clear (risk ratio 3.96, 95% CI 2.36 to 6.66; high-quality evidence) at week 12.

AUTHORS' CONCLUSIONS

This review found only one RCT evaluating the use of this type of biological therapy. Although the risk of publication bias was high, as we included only one industry-sponsored RCT, the risk of allocation, selection, performance, attrition, and selective reporting biases for all outcomes (except for CDLQI) was low, and no short-term serious adverse events were found.We can conclude, based on this single included study, that etanercept seems to be efficacious and safe (at least in the short term) for the treatment of paediatric psoriasis. However, as the GRADE approach refers not to individual studies but to a body of evidence, we shall wait for the results of the ongoing studies in a future update of this review. In addition, future studies should evaluate quality-of-life endpoints established a priori and standardise primary outcome measures such as PASI 75, and should include the PGA as a secondary endpoint. Also, collating and reporting adverse events uniformly is required to better evaluate safety.

The intestinal microbiome in human disease and how it relates to arthritis and spondyloarthritis

Humans and microbes have developed a symbiotic relationship over time, and alterations in this symbiotic relationship have been linked to several immune mediated diseases such as inflammatory bowel disease, type 1 diabetes and spondyloarthropathies. Improvements in sequencing technologies, coupled with a renaissance in 16S rRNA gene based community profiling, have enabled the characterization of microbiomes throughout the body including the gut. Improved characterization and understanding of the human gut microbiome means the gut flora is progressively being explored as a target for novel therapies including probiotics and faecal microbiota transplants. These innovative therapies are increasingly used for patients with debilitating conditions where conventional treatments have failed. This review discusses the current understanding of the interplay between host genetics and the gut microbiome in the pathogenesis of spondyloarthropathies, and how this may relate to potential therapies for these conditions.

The immunologic effects of estrogen on psoriasis: A comprehensive review

BACKGROUND

Immunological changes in pregnancy are associated with improvements in some pre-existing immune-mediated skin diseases. Estrogen has been hypothesized to contribute to these changes by creating a shift from Th1 and Th17 to Th2 immunity. As this hypothesis would predict, psoriasis (a primarily Th17 mediated immune disease) tends to improve during pregnancy. However, the precise mechanism by which estrogen induces immunological change in psoriasis remains poorly understood.

OBJECTIVE

To summarize the immunologic effects of estrogen as they relate to psoriasis during pregnancy.

METHODS

We performed an English-language PubMed search of articles from September 2004 to September 2014 combining the key terms "psoriasis," "estrogen," "autoimmune disease," and "pregnancy."

RESULTS

Estrogen appears to up-regulate Th2 cytokines and down-regulate Th1 and Th17 cytokines. This shift was initially observed in murine systems, which showed decreased mixed lymphocyte reactions of splenocytes and increased antibody production during pregnancy. Antigen stimulated splenocytes produced fewer Th1 cytokines and more Th2 cytokines in pregnant mice. IL17 producing T cells were significantly decreased in healthy pregnancies compared to non-pregnant controls.

LIMITATIONS

This review is limited by the paucity of studies evaluating immunological changes of psoriasis in pregnancy among human subjects.

CONCLUSIONS

Increased estrogen production in pregnancy is associated with decreased Th1 and Th17 cytokine production. While estrogen may be responsible for some of these immune shifts resulting in disease improvement, there remains no definitive evidence to prove the hypothesis that estrogen is responsible for such improvement.

SRSF1 facilitates cytosolic DNA-induced production of type I interferons recognized by RIG-I

BACKGROUND

Evidence has shown that psoriasis is closely associated with infection; however, the mechanism of this association remains unclear. In mammalian cells, viral or bacterial infection is accompanied by the release of cytosolic DNA, which in turn triggers the production of type-I interferons (IFNs). Type I IFNs and their associated genes are significantly upregulated in psoriatic lesions. RIG-I is also highly upregulated in psoriatic lesions and is responsible for IFN production. However, RIG-I mediated regulatory signaling in psoriasis is poorly understood.

METHODS

We screened a cDNA library and identified potential RIG-I interacting partners that may play a role in psoriasis.

RESULTS

We found that serine/arginine-rich splicing factor 1 (SRSF1) could specifically interact with RIG-I to facilitate RIG-I mediated production of type-I IFN that is triggered by cytosolic DNA. We found SRSF1 associates with RNA polymerase III and RIG-I in a DNA-dependent manner. In addition, treatment with a TNFα inhibitor downregulated SRSF1 expression in peripheral blood mononuclear cells (PBMCs) from psoriasis vulgaris patients.

DISCUSSION

Based on the abundance of pathogenic cytosolic DNA that is detected in psoriatic lesions, our finding that RIG-I interacts with SRSF1 to regulate type-I IFN production reveals a critical link regarding how cytosolic DNA specifically activates aberrant IFN expression. These data may provide new therapeutic targets for the treatment of psoriasis.

The translational revolution and use of biologics in patients with inflammatory skin diseases

Psoriasis and atopic dermatitis (AD) are common inflammatory skin diseases characterized by immune-mediated inflammation and abnormal keratinocyte differentiation. Although T-cell infiltration characterizes both diseases, T-cell polarization differs. Psoriasis is currently the best model for translational medicine because many targeted therapeutics have been developed and testing of targeted therapeutics has cemented psoriasis as IL-23/TH17 polarized. In patients with AD, although therapeutic development is approximately a decade behind that in patients with psoriasis, there is now active development and testing of targeted therapeutics against various immune axes (TH2, TH22, and IL-23/TH17). These clinical trials and subsequent molecular analyses using human samples will be able to clarify the relative roles of polar cytokines in patients with AD.

Microbes, the gut and ankylosing spondylitis

It is increasingly clear that the interaction between host and microbiome profoundly affects health. There are 10 times more bacteria in and on our bodies than the total of our own cells, and the human intestine contains approximately 100 trillion bacteria. Interrogation of microbial communities by using classic microbiology techniques offers a very restricted view of these communities, allowing us to see only what we can grow in isolation. However, recent advances in sequencing technologies have greatly facilitated systematic and comprehensive studies of the role of the microbiome in human health and disease. Comprehensive understanding of our microbiome will enhance understanding of disease pathogenesis, which in turn may lead to rationally targeted therapy for a number of conditions, including autoimmunity.

Biologics in dermatology: an integrated review

The advent of biologics in dermatologic treatment armentarium has added refreshing dimensions, for it is a major breakthrough. Several agents are now available for use. It is therefore imperative to succinctly comprehend their pharmacokinetics for their apt use. A concerted endeavor has been made to delve on this subject. The major groups of biologics have been covered and include: Drugs acting against TNF-α, Alefacept, Ustekinumab, Rituximab, IVIG and Omalizumab. The relevant pharmacokinetic characteristics have been detailed. Their respective label (approved) and off-label (unapproved) indications have been defined, highlighting their dosage protocol, availability and mode of administration. The evidence level of each indication has also been discussed to apprise the clinician of their current and prospective uses. Individual anti-TNF drugs are not identical in their actions and often one is superior to the other in a particular disease. Hence, the section on anti-TNF agents mentions the literature on each drug separately, and not as a group. The limitations for their use have also been clearly brought out.

The Expression of p63 during Epidermal Remodeling in Psoriasis

Psoriasis is a skin disorder of chronic keratinization characterized by epidermal hyperplasia, hyperkeratosis, and inflammation. However, little is known about the mechanism (s) underlying the hyperplasia with elongated rete ridges characteristic of psoriasis. The p63 transcription factor, a homologue of the p53 tumor suppressor, has been implicated in the maintenance of epidermal stem cells and the stratification of the epidermis. p63 is up-regulated in squamous cell carcinomas with anaplasia, suggesting that it is also associated with epidermal hyperplasia. In this study, we examined the expression of p63 in the remodeling of psoriatic epidermis. Lesional tissues from 17 psoriasis patients in various stages of plaque-type psoriasis and normal skin tissues from five healthy subjects were examined by immunohistochemistry using a monoclonal anti-p63 antibody. Normal epidermis stained positively for p63 in the basal cell layer and in 2 to 4 layers of the spinous cell layer. p63 was positive in the thickened rete ridges of the epidermis even in early psoriatic lesions. As the epidermis elongated, p63-positive cells moved down and were localized in the lower parts of the rete ridges where keratinocytes densely proliferated. From these results, we suggest that p63 may be involved in the early stage of the remodeling process of the psoriatic epidermis as well as in the elongation of the rete ridges.

Immunologic biomarkers for clinical and therapeutic management of psoriasis

BACKGROUND

The therapeutic management of psoriasis includes conventional treatments as well as the new generation of highly effective TNF-α inhibitors. However, psoriasis has proven to be a complex therapeutic challenge and treatment failures are not uncommon. Thus, laboratory biomarkers of disease progression/therapeutic efficacy may greatly help in the clinical management of psoriasis.

AIMS

To identify laboratory biomarkers for clinical management and therapeutic monitoring of psoriasis.

METHODS

An observational study performed on 59 patients, presenting moderate to severe psoriasis, undergoing treatment with anti-TNF-α agents (etanercept, adalimumab, and infliximab). Soluble and cellular immune/inflammatory parameters were assessed at baseline and after 12 and 24 weeks of treatment.

RESULTS

Clinical efficacy was achieved in 88% of the subjects at 12 weeks, reaching 90% after 24 weeks. IL-6 and IL-22, which were elevated at baseline, were significantly reduced, in association with a significant decrease of CLA+ T cells and an increase of Treg lymphocytes. T, B, and NK cell subsets and T cell response to recall antigens did not show any evidence of immune suppression.

CONCLUSIONS

Immune/inflammatory parameters including IL-6 and IL-22, CLA+ T cells, and Treg lymphocytes may prove to be valuable laboratory tools for the clinical and therapeutic monitoring of psoriasis.

Thymic stromal lymphopoietin links keratinocytes and dendritic cell-derived IL-23 in patients with psoriasis

BACKGROUND

Thymic stromal lymphopoietin (TSLP) is a major proallergic cytokine that promotes TH2 responses through dendritic cell (DC) activation. Whether it also plays a role in human autoimmune inflammation and associated pathways is not known.

OBJECTIVE

In this study we investigated the potential role of several epithelium-derived factors, including TSLP, in inducing IL-23 production by human DCs. We further dissected the role of TSLP in patients with psoriasis, an IL-23-associated skin autoimmune disease.

METHODS

The study was performed in human subjects using primary cells and tissue samples from patients with psoriasis and healthy donors. We analyzed the production of IL-23 in vitro by blood and skin DCs. We studied the function for TSLP and its interaction with other components of the inflammatory microenvironment in situ and ex vivo.

RESULTS

We found that TSLP synergized with CD40 ligand to promote DC activation and pathogenic IL-23 production by primary blood and skin DCs. In situ TSLP was strongly expressed by keratinocytes of untreated psoriatic lesions but not in normal skin. Moreover, we could demonstrate that IL-4, an important component of the TH2 inflammation seen in patients with atopic dermatitis, inhibited IL-23 production induced by TSLP and CD40 ligand in a signal transducer and activator of transcription 6-independent manner.

CONCLUSION

Our results identify TSLP as a novel player within the complex psoriasis cytokine network. Blocking TSLP in patients with psoriasis might contribute to decreasing DC activation and shutting down the production of pathogenic IL-23.

Systematic Review of Interleukin-12, Interleukin-17, and Interleukin-23 Pathway Inhibitors for the Treatment of Moderate-to-Severe Chronic Plaque Psoriasis

Background:

Monoclonal antibodies known as biologic agents specifically targeted against interleukin-12 (IL-12), interleukin-17A (IL-17), and interleukin-23 (IL-23) have been the focus of research for moderate-to-severe chronic plaque psoriasis in recent years.

Objectives:

To discuss the immune-mediated model of psoriasis and to summarize current knowledge of the clinical efficacy and safety of new biologic agents for moderate-to-severe chronic plaque psoriasis.

Methods:

The PubMed database was searched for relevant articles on ustekinumab, briakinumab, tildrakizumab (MK-322), guselkumab, secukinumab, ixekizumab, and brodalumab published between January 2005 and July 2013.

Results:

Fifty-five articles were identified. These studies suggest that the biologic agents specifically targeting IL-12, IL-17, and IL-23 are efficacious and safe in the treatment of moderate-to-severe psoriasis in adults.

Conclusion:

Current data from clinical trials suggest that biologic agents targeting IL-12, IL-17, and IL-23 are safe and efficacious drugs for use in moderate-to-severe chronic plaque psoriasis. Long-term data still need to be established.

Immunological and histological evaluation of clinical samples from psoriasis patients treated with anti-CD6 itolizumab

Psoriasis is a chronic inflammatory disease with a prevalence of approximately 2-3% in the general population. The majority of diagnosed patients have plaque psoriasis, and about 20% have moderate-to-severe disease. Itolizumab, a new monoclonal antibody specific for the CD6 molecule mainly expressed on T lymphocytes, has demonstrated to inhibit in vitro ligand-induced proliferation and pro-inflammatory cytokine production. We assessed the immunological and histopathological effect of the antibody using clinical samples taken from 26 patients with moderate-to-severe psoriasis included in a clinical trial. The precursor frequency of lymphocytes activated with anti-CD2/CD3/CD28 beads, as well as the number of interferon (IFN)-γ-secreting T cells after stimulation, were measured at different time points of the study. Serum cytokine levels and anti-idiotypic antibody response to itolizumab were also evaluated. Additionally, lymphocyte infiltration and epidermis hyperplasia were studied in five patients. A significant reduction in T cell proliferation capacity and number of IFN-γ-producing T cells was found in treated patients. Serum levels of interleukin-6, tumor necrosis factor and IFN-γ showed an overall trend toward reduction. No anti-idiotypic antibody response was detected. A significant reduction in the epidermis hyperplasia was observed in analyzed patients. These results support the relevance of the CD6 molecule as a therapeutic target for the treatment of this disease.

Serum leptin and adiponectin levels in Korean patients with psoriasis

Psoriasis is a disorder caused by genetic and immunological factors. Leptin, a peptide hormone secreted predominantly from adipose tissue, regulates energy intake and expenditure, as well as the T-helper response. There have been conflicting reports regarding serum levels of leptin and adiponectin in patients with psoriasis. In the present study, we measured serum levels of leptin and adiponectin in Korean patients with psoriasis. Twenty-four patients with psoriasis and fifteen control subjects were included in the study. Serum leptin and adiponectin levels were determined by an immunometric sandwich enzyme-linked immunosorbent assay (ELISA). The mean serum leptin concentration in patients with psoriasis was higher than in controls, and the difference was statistically significant. In contrast, serum adiponectin levels in patients with psoriasis were significantly decreased compared with healthy controls. Leptin levels in vitamin D-deficient patients were statistically significantly higher than in vitamin D-sufficient patients. Serum adiponectin concentrations showed a negative correlation with body mass index (BMI) and psoriasis area and severity index (PASI) in patients with psoriasis. In conclusion, the present study demonstrated that leptin and adiponectin may play a role in the immunopathogenesis of psoriasis and may be useful biomarkers indicating severity of psoriasis in Korean patients.

Polyandric acid A, a clerodane diterpenoid from the Australian medicinal plant Dodonaea polyandra, attenuates pro-inflammatory cytokine secretion in vitro and in vivo

Dodonaea polyandra is a medicinal plant used traditionally by the Kuuku I'yu (Northern Kaanju) indigenous people of Cape York Peninsula, Australia. The most potent of the diterpenoids previously identified from this plant, polyandric acid A (1), has been examined for inhibition of pro-inflammatory cytokine production and other inflammatory mediators using well-established acute and chronic mouse ear edema models and in vitro cellular models. Topical application of 1 significantly inhibited interleukin-1β production in mouse ear tissue in an acute model. In a chronic skin inflammation model, a marked reduction in ear thickness, associated with significant reduction in myeloperoxidase accumulation, was observed. Treatment of primary neonatal human keratinocytes with 1 followed by activation with phorbol ester/ionomycin showed a significant reduction in IL-6 secretion. The present study provides evidence that the anti-inflammatory properties of 1 are due to inhibition of pro-inflammatory cytokines associated with skin inflammation and may be useful in applications for skin inflammatory conditions including psoriasis and dermatitis.

Biological Therapy for Pyoderma Gangrenosum

Introduction: pyoderma gangrenosum (PG) is a rare and severe neutrophilic dermatosis associated with inflammatory bowel disease (IBD) and other systemic diseases such as rheumatoid arthritis and hematological malignancies. Diagnosis is based on clinical criteria and exclusion of other skin disorders. There is no gold standard for the treatment of PG; traditionally intravenous corticosteroids are used, but recently the use of drugs that inhibit tumor necrosis factor alpha (TNF-alpha) has changed the management of PG, showing great effectiveness.

Case report: female patient, 23 years old, diagnosed with severe nonspecific ulcerative colitis (UC) three years ago, undergoing treatment with oral mesalamine and azathioprine. She developed PG fourteen days after hospital discharge; hospitalization was due to worsening of intestinal disease symptoms. She was successfully treated using biological therapy after unfavorable evolution with corticosteroid therapy.

Conclusion: PG, a rare extraintestinal manifestation of IBD of difficult resolution that has significant impact on patient quality of life. The use of biological therapy for PG has higher efficacy in the treatment of patients decreasing wound healing time and return to daily activities.

The risk of herpes zoster during biological therapy for psoriasis and other inflammatory conditions

Recent advances in biological therapies have proved highly effective in treating psoriasis and other inflammatory conditions, including psoriatic arthritis, rheumatoid arthritis, inflammatory bowel disease and ankylosing spondylitis. However, adverse effects related to their immunosuppression have been observed, including an increased propensity to viral infections. This review evaluates the evidence of herpes zoster (HZ) risk from biologics based on clinical reports, cohort studies and randomized controlled studies. The risk of HZ associated with these agents remains controversial, especially when comparing their risk with non-biological therapy used to treat the same inflammatory conditions. This review specifically assesses the risk of the TNF inhibitors etanercept, adalimumab and infliximab, as well as interleukin-12/23 inhibitor ustekinumab. We found multiple cohort studies, randomized controlled trials and case reports that suggest infliximab increases risk of HZ, whereas adalimumab, etanercept and ustekinumab HZ risk remain controversial. Nevertheless, HZ vaccination should be considered prior to initiation of biological therapy, particularly infliximab.

From the Medical Board of the National Psoriasis Foundation: The risk of cardiovascular disease in individuals with psoriasis and the potential impact of current therapies

BACKGROUND

Many studies have identified cardiovascular risk factors in patients with psoriasis. Some psoriasis therapies may increase cardiovascular disease (CVD) and others may decrease CVD.

OBJECTIVE

We reviewed the literature to define the impact of common psoriasis therapies on cardiovascular measures and outcomes.

RESULTS

Phototherapy has no major cardiovascular impact and may reduce levels of proinflammatory cytokines. Acitretin increases serum lipids and triglycerides, but has not been shown to increase cardiovascular risk. Cyclosporine A increases blood pressure, serum triglycerides, and total cholesterol. Methotrexate is associated with a decreased risk of CVD morbidity and mortality. Among the biologics, data for tumor necrosis factor inhibitors suggest an overall reduction in cardiovascular events. Most data on short-term ustekinumab use suggest no effect on major adverse cardiovascular events, however some authorities remain concerned. Nevertheless, ustekinumab use over a 4-year period shows a decrease in major adverse cardiovascular events when compared both with the general US population and with psoriatics in Great Britain.

LIMITATIONS

Most studies lack the power and randomization of large clinical trials and long-term follow-up periods. In addition, the increased risk of CVD associated with psoriasis itself is a confounding factor.

CONCLUSION

Some therapies for moderate to severe psoriasis, including methotrexate and tumor necrosis factor inhibitors, may reduce cardiovascular events in psoriatic patients. Ustekinumab appears to be neutral but there may be a long-term benefit. Appropriate patient counseling and selection and clinical follow-up are necessary to maximize safety with these agents. Further long-term study is necessary to quantify the benefits and risks associated with biologic therapies.

[Psoriasis: physiopathology and immunogenetics]

Psoriasis is a multifactorial disease that involves genetic, immunological and environmental factors. During the last decade, several studies by genome scan on families or cases/controls helped to highlight more than ten loci "PSORS" located on different chromosomes and containing several candidate genes. Psoriasis appears as a genetic disease that follows the mixed model with the involvement of a major gene (PSORS1) and a set of minor genes with a variable penetrance depending on the locus. Genetic data have focused on the involvement of the immune system in the pathogenesis of psoriasis. It is now accepted that psoriasis is an immunological disease involving the response profiles TH1 and TH17. Much remains to be done to better elucidate the mechanisms involved in the genesis of psoriatic lesions to find new therapeutic targets.

The expression of proinflammatory genes in epidermal keratinocytes is regulated by hydration status

Mucosal wounds heal more rapidly, exhibit less inflammation, and are associated with minimal scarring when compared with equivalent cutaneous wounds. We previously demonstrated that cutaneous epithelium exhibits an exaggerated response to injury compared with mucosal epithelium. We hypothesized that treatment of injured skin with a semiocclusive dressing preserves the hydration of the skin and results in a wound healing phenotype that more closely resembles that of mucosa. Here we explored whether changes in hydration status alter epidermal gene expression patterns in rabbit partial-thickness incisional wounds. Using microarray studies on injured epidermis, we showed that global gene expression patterns in highly occluded versus non-occluded wounds are distinct. Many genes including IL-1β, IL-8, TNF-α (tumor necrosis factor-α), and COX-2 (cyclooxygenase 2) are upregulated in non-occluded wounds compared with highly occluded wounds. In addition, decreased levels of hydration resulted in an increased expression of proinflammatory genes in human ex vivo skin culture (HESC) and stratified keratinocytes. Hierarchical analysis of genes using RNA interference showed that both TNF-α and IL-1β regulate the expression of IL-8 through independent pathways in response to reduced hydration. Furthermore, both gene knockdown and pharmacological inhibition studies showed that COX-2 mediates the TNF-α/IL-8 pathway by increasing the production of prostaglandin E2 (PGE2). IL-8 in turn controls the production of matrix metalloproteinase-9 in keratinocytes. Our data show that hydration status directly affects the expression of inflammatory signaling in the epidermis. The identification of genes involved in the epithelial hydration pathway provides an opportunity to develop strategies to reduce scarring and optimize wound healing.

Metabolic syndrome and skin: psoriasis and beyond

Metabolic syndrome (Met S) is a clustering of risk factors comprising of abdominal obesity, dyslipidemia, elevated blood pressure, and abnormal glucose tolerance. The prevalence of Met S has been increasing in the last few years throughout the world. Psoriasis has consistently been associated with Met S as well as its various components. However, the association is no longer limited to psoriasis alone. Various dermatological conditions such as lichen planus, androgenetic alopecia, systemic lupus erythematosus, skin tags, acanthosis nigricans, and even cutaneous malignancies have also been found to be associated with this syndrome. Though chronic inflammation is thought to be the bridging link, the role of oxidative stress and endocrine abnormalities has recently been proposed in bringing them together.

Promising new treatments for psoriasis

Psoriasis is a chronic, proliferative, and inflammatory skin disease affecting 2-3% of the population and is characterized by red plaques with white scales. Psoriasis is a disease that can affect many aspects of professional and social life. Currently, several treatments are available to help control psoriasis such as methotrexate, ciclosporin, and oral retinoids. However, the available treatments are only able to relieve the symptoms and lives of individuals. The discovery of new immunological factors and a better understanding of psoriasis have turned to the use of immunological pathways and could develop new biological drugs against specific immunological elements that cause psoriasis. Biological drugs are less toxic to the body and more effective than traditional therapies. Thus, they should improve the quality of life of patients with psoriasis. This review describes new psoriasis treatments, which are on the market or currently in clinical trials that are being used to treat moderate-to-severe plaque psoriasis. In addition, this paper describes the characteristics and mechanisms in detail. In general, biological drugs are well tolerated and appear to be an effective alternative to conventional therapies. However, their effectiveness and long-term side effects need to be further researched.

Psoriasis vulgaris and familial cancer risk- a population-based study

Background

Follow-up studies of psoriasis patients indicate an increased risk in the occurrence of malignancies at different sites of origin. Population stratification and/or complicated interpretation of evidence on the risk of cancer (due to the small number of patients included in most series) lead to inconsistent data. Herein we investigated the risk of occurrence of malignancies at different sites of origin in a series of 517 psoriasis patients and their 1st degree relatives.

Methods

We evaluated the tumour spectrum as well as the age of the patient at diagnosis of cancers in psoriasis families along with the observed and expected frequencies of malignancies. The distribution of 17 common mutations/polymorphisms in 10 known cancer susceptibility genes among psoriasis patients and 517 matched healthy controls were examined. No such study has been published to date.

Results

The statistical comparison of the observed and expected frequencies of cancers revealed a higher than expected occurrence of Hodgkin’s lymphoma among males in psoriasis families when compared to the general population (OR=1.8, 95%CI 1.6-2.1, p=0.002). There was a non-significant tendency towards a younger age of onset and overrepresentation of laryngeal cancer and leukaemia in psoriasis families. We found no major differences in the distribution of cancer susceptibility mutations among our cases and the healthy controls.

Conclusions

The results of our study suggest an increased risk of Hodgkin’s lymphoma for male members of psoriasis families. Further studies are needed to confirm the findings and to evaluate whether or not the application of cancer surveillance protocols for Hodgkin’s lymphoma, leukaemia and laryngeal cancer are justified in these families.

IL-17 targeted therapies for psoriasis

INTRODUCTION

Psoriasis is a chronic, disabling, inflammatory skin disease whose pathogenesis still remains to be fully elucidated. Genetic and environmental factors induce an immune response mediated by several cytokines and chemokines, including IL-17A.

AREAS COVERED

Emerging evidence now suggests that IL-17A is central in the pathogenesis of psoriasis. Three agents neutralizing IL-17 (i.e., secukinumab and ixekizumab) or antagonizing its receptor (i.e., brodalumab) are in development and are being studied in Phase III clinical trials to evaluate their overall efficacy and safety. However, Phase II results of IL-17 blockade with each of these agents has shown a marked improvement of disease severity, thus confirming the pathogenic relevance of IL-17 in mediating crucial inflammatory circuits in psoriasis.

EXPERT OPINION

Anti-IL-17 agents are likely to become important future therapeutics in this disease and the may potentially impact on cardiovascular diseases, arthritis and other comorbidities associated with psoriasis.

An Overview of the Pharmacokinetics and Pharmacodynamics of Efalizumab: A Monoclonal Antibody Approved for Use in Psoriasis

Efalizumab is a recombinant humanized monoclonal IgG(1) antibody shown to be efficacious for the treatment of moderate to severe chronic plaque psoriasis. Efalizumab, a targeted inhibitor of T cell interactions, binds to the CD11a subunit of lymphocyte function-associated antigen 1 (LFA-1), thereby preventing LFA-1 binding to intercellular adhesion molecule 1 (ICAM-1). The authors review the pharmacokinetic and pharmacodynamic data from the efalizumab clinical development program and discuss how these data led to selection of the optimal weekly subcutaneous (SC) dose of efalizumab (1.0 mg/kg) in adults. Efalizumab SC dosages of 1.0 mg/kg/wk or greater exerted maximal pharmacodynamic effects for CD11a expression and available CD11a binding sites on T lymphocytes. Dosages greater than 1.0 mg/kg/wk SC did not provide additional benefits; moreover, higher doses did not alter the safety profile. During long-term administration of efalizumab, serum levels were generally stable and pharmacodynamic markers remained maximally affected.

Pharmacokinetics and Pharmacodynamics of Multiple Weekly Subcutaneous Efalizumab Doses in Patients With Plaque Psoriasis

Efalizumab pharmacokinetics, pharmacodynamics, and efficacy were assessed after subcutaneous administration of 1.0 or 2.0 mg/kg/wk for 12 weeks with 12 weeks of follow-up in subjects with psoriasis. Steady-state serum concentrations were achieved by 4 and 8 weeks, respectively. C(max) was 12 and 31 microg/mL, occurring approximately 2 days after a SC dose. Serum trough levels were 9 and 24 microg/mL, and CL/F(ss) was 24 and 16 mL/kg/d. At both doses, CD11a expression on T lymphocytes was maximally down-modulated to approximately 20% of baseline, and CD11a binding sites were >95% saturated. The extent of this PD effect was less for other leukocytes. Leukocyte counts increased by approximately 40%, with the majority of this increase related to a significant but reversible increase in the lymphocyte population. Maximal pharmacodynamic effects were sustained at both dose levels through the course of treatment and were commensurate with improvements in psoriasis.

Therapeutic targeting of eosinophil adhesion and accumulation in allergic conjunctivitis

Considerable evidence indicates that eosinophils are important effectors of ocular allergy. Increased worldwide prevalence of allergic eye pathologies has stimulated the identification of novel drug targets, including eosinophils and adhesion molecules. Accumulation of eosinophils in the eye is a key event in the onset and maintenance of allergic inflammation and is mediated by different adhesion molecules. Antihistamines with multiple mechanisms of action can be effective during the early and late phases of allergic conjunctivitis by blocking the interaction between β(1) integrins and vascular cell adhesion molecule (VCAM)-1. Small molecule antagonists that target key elements in the process of eosinophil recruitment have been identified and reinforce the validity of α(4)β(1) integrin as a therapeutic target. Glucocorticoids are among the most effective drugs for ocular allergy, but their use is limited by adverse effects. Novel dissociated glucocorticoids can prevent eosinophil accumulation and induce apoptosis of eosinophils, making them promising candidates for ophthalmic drugs. This article reviews recent understanding of the role of adhesion molecules in eosinophil recruitment in the inflamed conjunctiva along with effective treatments for allergic conjunctivitis.

Etanercept suppresses regenerative hyperplasia in psoriasis by acutely downregulating epidermal expression of interleukin (IL)-19, IL-20 and IL-24

BACKGROUND

Psoriasis is a Th17/Th1-mediated skin disease that often responds to antitumour necrosis factor (TNF)-α therapies, such as etanercept.

OBJECTIVES

To better define mechanisms by which etanercept improves psoriasis and to gain insight into disease pathogenesis.

METHODS

We investigated the early biochemical and cellular effects of etanercept on skin lesions in responder patients prior to substantial clinical improvement (≤ 4 weeks).

RESULTS

By 1 week, etanercept acutely suppressed gene expression of the interleukin (IL)-20 subfamily of cytokines (IL-19, IL-20, IL-24), which were found to be predominantly epidermis-derived and which are implicated in stimulating epidermal hyperplasia. Additionally, by 1 week of therapy, suppression of other keratinocyte-derived products (chemokines, antimicrobial proteins) occurred, while suppression of epidermal regenerative hyperplasia occurred within 1-3 weeks. Th17 elements (IL-23p19, IL-12p40, IL-17A, IL-22) were suppressed by 3-4 weeks. In vitro, TNF-α and IL-17A coordinately stimulated the expression of the IL-20 subfamily in normal keratinocytes.

CONCLUSIONS

Based on the rapid suppression of regenerative hyperplasia, chemokines and other keratinocyte-derived products, including the IL-20 subfamily, we propose that epidermal activation is a very early target of etanercept. As many of these keratinocyte markers are stimulated by TNF-α, their rapid downregulation is likely to reflect etanercept's antagonism of TNF-α. Additionally, decreased epidermal hyperplasia might result specifically from acute suppression of the IL-20 subfamily, which is also a likely consequence of etanercept's antagonism of TNF-α. Thus, the IL-20 subfamily has potential importance in the pathogenesis of psoriasis and therapeutic response to etanercept.

Reviewing concepts in the immunopathogenesis of psoriasis

Insights into the pathogenesis of psoriasis led to the development of therapeutic tools aimed at blocking its immunological trigger. In parallel, cytokines such as the tumor necrosis factor (TNF) have been recognized as playing a crucial role in the pathogenesis of psoriasis and its associated comorbidities. Genetic and immunological studies have contributed effectively towards establishing the currently held concepts regarding this complex disease.

Transcriptome classification reveals molecular subtypes in psoriasis

BACKGROUND

Psoriasis is an immune-mediated disease characterised by chronically elevated pro-inflammatory cytokine levels, leading to aberrant keratinocyte proliferation and differentiation. Although certain clinical phenotypes, such as plaque psoriasis, are well defined, it is currently unclear whether there are molecular subtypes that might impact on prognosis or treatment outcomes.

RESULTS

We present a pipeline for patient stratification through a comprehensive analysis of gene expression in paired lesional and non-lesional psoriatic tissue samples, compared with controls, to establish differences in RNA expression patterns across all tissue types. Ensembles of decision tree predictors were employed to cluster psoriatic samples on the basis of gene expression patterns and reveal gene expression signatures that best discriminate molecular disease subtypes. This multi-stage procedure was applied to several published psoriasis studies and a comparison of gene expression patterns across datasets was performed.

CONCLUSION

Overall, classification of psoriasis gene expression patterns revealed distinct molecular sub-groups within the clinical phenotype of plaque psoriasis. Enrichment for TGFb and ErbB signaling pathways, noted in one of the two psoriasis subgroups, suggested that this group may be more amenable to therapies targeting these pathways. Our study highlights the potential biological relevance of using ensemble decision tree predictors to determine molecular disease subtypes, in what may initially appear to be a homogenous clinical group. The R code used in this paper is available upon request.

Tolerability, pharmacokinetics and pharmacodynamics of CMAB001, an anti-CD11a antibody, in Chinese healthy volunteers and psoriatic patients

AIM

To evaluate the pharmacokinetics (PK), pharmacodynamics (PD) and primary tolerability of an anti-CD11a monoclonal antibody (CMAB001) in Chinese healthy volunteers and psoriatic patients.

METHODS

Two open-label studies were conducted. One was a parallel-group, single-center, dose-escalation test, including 24 healthy adult volunteers from 18 to 45 years in age. All subjects randomly received a single subcutaneous injection dose of 0.5, 1.0 or 2.0 mg/kg. The other was a multiple-dose study: 10 adult psoriatic patients were administered weekly subcutaneous injections of 1.0 mg/kg for 7 weeks.

RESULTS

CMAB001 was well tolerated in the single- and multiple-dose studies. Slow absorption was observed in both studies. In the single-dose study, the concentration of CMAB001 reached its highest level 2 d later after the injection, and the C(max) increased in an approximate dose-proportionate manner, while the area under curve (AUC) showed much greater than dose-proportionate increase. In the multiple-dose study, the steady-state serum concentration level was attained following the 4th injection.

CONCLUSION

CMAB001 exhibited a nonlinear pharmacokinetic profile over the dose range from 0.5 to 2.0 mg/kg, and was well tolerated in healthy volunteers and psoriatic patients.