Psoriasis: current perspectives with an emphasis on treatment

Latest on biomaterial-based therapies for topical treatment of psoriasis

Psoriasis is an autoimmune inflammatory disease which is fundamentally different from dermatitis. Its treatments include topical medications and systemic drugs depending on different stages of the disease. However, these commonly used therapies are falling far short of clinical needs due to various drawbacks. More precise therapeutic strategies with minimized side effects and improved compliance are highly demanded. Recently, the rapid development of biomaterial-based therapies has made it possible and promising to attain topical psoriasis treatment. In this review, we briefly describe the significance and challenges of the topical treatment of psoriasis and emphatically overview the latest progress in novel biomaterial-based topical therapies for psoriasis including microneedles, nanoparticles, nanofibers, and hydrogels. Current clinical trials related to each biomaterial are also summarized and discussed.

Quality of life of patients living with psoriasis: a qualitative study

BACKGROUND

Psoriasis is a multifactorial inflammatory disease prevalent in dermatology. We aimed to understand the perceptions of patients living with psoriasis in relation to their quality of life and to identify aspects to improve it.

METHODS

This is qualitative research carried out in a dermatology outpatient clinic of the São Paulo State University (UNESP) medical school, Botucatu, Brazil, with 81 psoriasis patients. The interviews were transcribed and analysed using the Discourse of the Collective Subject method (DCS).

RESULTS

Quality of life was linked to well-being, happiness, leisure, good food and financial stability. However, disease symptoms, social and clothing restrictions, impairment of professional activities and the absence of a cure, negatively influenced their perceptions. Suggestions for improvements included an increase of public awareness, stress reduction, disease acceptance and multidisciplinary care.

CONCLUSION

The meanings of quality of life revealed by the participants are subjective, multidimensional, linked to moments experienced by them and to the health-disease process. Public health policies promoting reduction in social stigma and stress as well as multidisciplinary approaches towards care can contribute to improvements of QoL in psoriasis.

Biologic Therapy Utilization in Patients With Moderate to Severe Psoriasis and Psoriatic Arthritis: An Observational Summary of Biologic Therapy Use in a Clinical Setting

Plaque psoriasis affects approximately 2% to 3% of the global population, with psoriatic arthritis observed in approximately 20% to 30% of these individuals. Upon advances in research pathophysiology and treatment over the past decade, biologic therapies have been used more to treat moderate to severe psoriasis. In Canada, reimbursement bodies have defined prior authorization criteria to determine patient eligibility for funding of biologic treatments in moderate to severe plaque psoriasis. Generally, patients will have been treated with conventional therapies such as topical steroids, phototherapy, or systemic treatments such as methotrexate and cyclosporine before starting a biologic therapy. In difficult cases or severe flares in otherwise controlled disease, practitioners may augment the regimen with one or more conventional treatments. The objective of this observational report was to identify treatment pathways for psoriasis and psoriatic arthritis patients in Canada by examining initial biologic treatment and subsequent treatment optimization patterns for informed reimbursement discussions and decisions. A retrospective chart review was conducted at Newlab Clinical Research using medical records of patients who received at least 1 of 4 biologic agents approved at that time of the survey in Canada for the treatment of plaque psoriasis (adalimumab, etanercept, infliximab, ustekinumab). The study population consisted of patients who had moderate to severe plaque psoriasis, diagnosed by a dermatologist, for at least 6 months before the study index date and who attended Newlab Clinical Research between 2008 and 2013. All current and previous agents prescribed for the treatment of psoriasis were captured. A total of 248 patients with psoriasis treated with biologics were identified, of whom 27 (10.9%) were also diagnosed with psoriatic arthritis. Prior to initiating treatment with a biologic, most patients (72.1%) were treated with (or contraindicated to) methotrexate/cyclosporine. Treatment was supplemented with topical agents (70.6%) and/or followed by a course of ultraviolet light phototherapy (51.6%). Only 2.4% of patients were treated with a biologic first. Of 248 patients treated with biologics, almost half (47.6%) needed add-on therapy, whereas 16.5% of patients had an increase in dose or dosing interval. Furthermore, 14.1% of patients added a topical agent, 10.5% a topical steroid, or 6.5% a course of phototherapy while continuing biologic therapies. Finally, 30.4% of patients switched to another biologic treatment. Adalimumab was the most common agent used as a second-line agent (37.2%), and patients who started on adalimumab mainly switched to ustekinumab as a second-line agent (73.9%). Infliximab was the agent least often used as second-line therapy.

Superiority of a vitamin B12-containing emollient compared to a standard emollient in the maintenance treatment of mild-to-moderate plaque psoriasis

Psoriasis is a chronic inflammatory skin disease affecting 2%-3% of the population. The wide range of drugs currently available for its treatment could be associated, in the long term, with organ toxicity and adverse events, thus, clinical monitoring throughout treatment is required. This investigator-initiated trial (IIT) evaluated the efficacy and the safety of a vitamin B12-containing ointment in comparison with glycerol-petrolatum-based emollient cream used twice a day to treat mild-to-moderate plaque psoriasis for a period over 12 weeks followed by a wash-out observation period of 4 weeks. This study was conducted as a randomized, controlled, single-blind, intra-patient left- to right-side trial comparing the efficacy and safety of vitamin B12-containing ointment (M-treatment) with a glycerol-petrolatum-based emollient cream (C-treatment). The Psoriasis Area Severity Index (PASI) was determined at baseline (T0), at time points T2 (14 days), T4 (4 weeks), T8 (8 weeks), T12 (12 weeks) and 4 weeks after the end of the wash-out period (F1). In total, 24 patients with plaque psoriasis were randomized to receive left- or right-side treatment with B12 ointment. From time point T2 to time point F1, there was a statistically significant difference in PASI reduction between M-treatment side and C-treatment side. At time point T 12, the difference between the mean reductions from baseline PASI scores by 5.92 ± 2.49 (87, 6%) in the M-treatment side versus 1.08 ± 1.02 (23, 1%) C-treatment side was statistically highly significant ( PWex < 0.001). On the contemporary panorama in the treatment of psoriasis, we conclude that vitamin B12 ointment will represent a new concrete therapy option and should be considered in the update of therapeutic algorithm for the treatment of psoriasis.

Casual or Causal? Two Unique Cases of Hodgkin's Lymphoma: A Case Report and Literature Review

Case series

Patient: Male, 38 • Male, 30

Final Diagnosis: Hodgkin’s lymphoma

Symptoms: Lymphadenopathy • shortness of breath

Medication: —

Clinical Procedure: —

Specialty: Oncology

Anti-proliferative and anti-inflammatory effects of 3β,6β,16β-Trihydroxylup-20(29)-ene on cutaneous inflammation

ETHNOPHARMACOLOGICAL RELEVANCE

3β,6β,16β-Trihydroxylup-20(29)-ene (TTHL) is a triterpene isolated from the flowers of Combretum leprosum, a plant used in folk medicine in the north of Brazil for the treatment of skin disorders.

AIM OF THE STUDY

In the present study, TTHL was evaluated as a potential topical anti-inflammatory and anti-proliferative agent through in vivo and in vitro models.

MATERIAL AND METHODS

Anti-inflammmatory and anti-proliferative effects of TTHL were assessed using Swiss mice in acute and chronic models of skin inflammation induced by 12-O-tetradecanoylphorbol-acetate (TPA) application. Anti-proliferative activity was proved through in vitro experiments with the HaCaT human keratinocyte cell line.

RESULTS

Treatment with TTHL inhibited inflammatory parameters such as oedema formation and cellular infiltration in acute and chronic models. In the chronic model, TTHL also inhibited epidermal hyperproliferation, as evidenced by reduction of epidermis thickness and proliferating cell nuclear antigen expression. The anti-proliferative effect was confirmed by the capability of TTHL in reducing the proliferation and inducing cell apoptosis of HaCaT cells. Suggesting a mechanism of action, TTHL showed activation of corticosteroid receptors, but without the induction of corticosteroid-related cutaneous side effects.

CONCLUSION

Our results demonstrate consistent anti-inflammatory and anti-proliferative activity and assign TTHL as a valuable tool in the development of a new treatment for skin inflammatory and proliferative diseases, such as psoriasis.

Integrating Biologic Agents into Management of Moderate-to-Severe Psoriasis: A Consensus of the Canadian Psoriasis Expert Panel

Background:

Approximately 2% of people worldwide have psoriasis, with as many as 1 million people with psoriasis in Canada alone.1,2 The severity of psoriasis ranges from mild to severe. It can lead to substantial morbidity and psychological stress and have a profound negative impact on patient quality of life.3,4 Although available therapies reduce therapies reduce the extent and severity of the disease and improve quality of life,3 reports have indicated a patient preference for more aggressive therapy and a dissatisfaction with the effectiveness of current treatment options.5

Objective:

A Canadian Expert Panel, comprising Canadian dermatologists, convened in Toronto on 27 February 2004 to reach a consensus on unmet needs of patients treated with current therapies and how to include the pending biologic agents in and improve the current treatment algorithm for moderate-to-severe psoriasis. Current treatment recommendations suggest a stepwise strategy starting with topical agents followed by phototherapy and then systemic agents.3,6,7 The Panel evaluated the appropriate positioning of the biologic agents, once approved by Health Canada, for the treatment of moderate-to-severe psoriasis.

Methods:

The Panel reviewed available evidence and quality of these data on current therapies and from randomized, controlled clinical trials.8–14 Subsequently, consensus was achieved by small-group workshops followed by plenary discussion.

Results:

The Panel determined that biologic agents are an important addition to therapies currently available for moderate-to-severe psoriasis and proposed an alternative treatment algorithm to the current step wise paradigm.

Conclusion:

The Panel recommended a new treatment algorithm for moderate-to-severe psoriasis whereby all appropriate treatment options, including biologic agents, are considered together and patients' specific characteristics and needs are taken into account when selecting the most appropriate treatment option.

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.

Root extract of water dropwort, Oenanthe javanica (Blume) DC, induces protein and gene expression of phase I carcinogen-metabolizing enzymes in HepG2 cells

Background

Cytochrome P450 (CYP) isoenzymes are an important phase I enzyme system. In the present study, we investigated the effects of Oenanthe javanica (Blume) DC on CYP1A1 and CYP1A2.

Findings

Whole plants were completely dried and then divided into leaves, stems, and roots for extraction. The human liver hepatocellular carcinoma cell line HepG2 was treated with ethanol extracts of these organs for 72 h and mRNA and protein expression levels were assessed. The root extract of O. javanica significantly elevated the expression of both CYP1A1 and CYP1A2 mRNAs (by 68 and 102 %, respectively). Similarly, the CYP1A1 and CYP1A2 protein levels were increased by the root extract (by 112 and 157 %, respectively). The effects of the root extract were much more pronounced than those of leaf and stem extracts. Subsequent GC–MS analysis revealed that the levels of major coumarin derivatives, xanthotoxin, bergapten, and isopimpinellin, were significantly higher in O. javanica root extracts than in leaf or stem extracts. Of note, 5 μM xanthotoxin (the most abundant furanocoumarin in O. javanica) induced the expression of CYP1A1 mRNA as well as CYP1A2 mRNA and protein, albeit the CYP1A1 protein level was elevated only at 10 μM xanthotoxin.

Conclusions

Although it is difficult to extrapolate such effects to metabolic outcomes because of the inherent limitations of in vitro experiments, it is important to note that dietary exposure to O. javanica may modulate phase I enzymes and thereby affect various xenobiotic metabolism.

Electronic supplementary material

The online version of this article (doi:10.1186/s40064-016-2078-8) contains supplementary material, which is available to authorized users.

1,4-dihydroxy-2-naphthoic Acid Induces Apoptosis in Human Keratinocyte: Potential Application for Psoriasis Treatment

Psoriasis, which affects approximately 1–3% of the population worldwide, is a chronic inflammatory skin disorder characterized by epidermal keratinocytes hyperproliferation, abnormal differentiation, and inflammatory infiltration. Decrease in keratinocyte apoptosis is a specific pathogenic phenomenon in psoriasis. Chinese herbs have been used for the treatment of psoriasis in China showing promising effect in clinical trials. A traditional Chinese medicine has relatively fewer side effects with longer remission time and lower recurrence rate. The extract of Rubia cordifolia L. (EA) was previously found by us to induce HaCaT keratinocytes apoptosis. In this study we identified one of the components in Rubia cordifolia L., the anthraquinone precursor 1,4-dihydroxy-2-naphthoic acid (DHNA), induces HaCaT keratinocytes apoptosis through G0/G1 cell cycle arrest. We have also demonstrated that DHNA acts through both caspase-dependent and caspase-independent pathways. Besides, cytotoxicity and IL-1α release assays indicate that DHNA causes less irritation problems than dithranol, which is commonly employed to treat psoriasis in many countries. Since DHNA possesses similar apoptotic effects on keratinocytes as dithranol but causes less irritation, DHNA therefore constitutes a promising alternative agent for treating psoriasis. Our studies also provide an insight on the potential of using EA and DHNA, alternatively, as a safe and effective treatment modality for psoriasis.

Physico-chemical characteristics of methotrexate-entrapped oleic acid-containing deformable liposomes for in vitro transepidermal delivery targeting psoriasis treatment

This study aimed to investigate the physico-chemical characteristics and in vitro permeability of methotrexate (MTX)-entrapped deformable liposomes prepared from phosphatidylcholine (PC) and oleic acid (OA), comparing with those of MTX-entrapped conventional liposomes prepared from PC and cholesterol (CH). Two formulations of MTX-entrapped PC2:CH1 and PC9:CH1 liposomes and one formulation of MTX-entrapped PC2.5:OA1 liposomes were prepared. The size, size distribution, zeta potential, thermal properties, entrapment efficiency, stability, and in vitro permeability across a porcine skin of the MTX-entrapped liposomes were evaluated. All liposome formulations showed a narrow size distribution with the size range of 80-140 nm which is appropriate for the skin permeability. The percentage of MTX loading, entrapment efficiency and the stability of MTX-entrapped PC2:CH1 and PC9:CH1 liposomes were slightly higher than those of MTX-entrapped PC2.5:OA1 liposomes. However, the MTX-entrapped PC2.5:OA1 liposomes enhanced the skin permeability characterized by the higher concentration and flux of MTX diffused across or accumulated in the epidermis and dermis layers of porcine skin. The enhanced permeability of MTX-entrapped PC2.5:OA1 liposomes was explained by 2 mechanisms: (1) the deformable and elasticity characteristics of OA-containing liposomes and (2) a property as a skin penetration enhancer of OA. This suggested that the PC2.5:OA1 deformable liposome was one of promising candidates to enhance the permeability of MTX for the treatment of psoriasis.

Celastrol-induced apoptosis in human HaCaT keratinocytes involves the inhibition of NF-κB activity

Psoriasis is a chronic inflammatory skin disease affecting 1-3% of the world's population. Traditional Chinese medicines have been extensively used for treating psoriasis with promising clinical results. Celastrol, a triterpenoid isolated from a Chinese herb Celastrus orbiculatus caulis, has been known to have diverse pharmacological effects such as anti-inflammatory, anti-cancer and antioxidant activities. The present study aimed at evaluating the anti-proliferative action of celastrol on cultured HaCaT cells and elucidating the mechanisms of action involved. Celastrol was shown to inhibit HaCaT cells growth with an IC₅₀ value of 1.1 μM as measured by MTT assay. The ability of celastrol to induce apoptosis was studied by flow cytometric and western blot analyses. Celastrol was found to be capable of inducing apoptosis in HaCaT cells as characterized by phosphatidyl-serine (PS) externalization, depolarization of mitochondrial membrane potential and activation of caspase-3. The apoptosis induced by celastrol could be suppressed by Z-IETD-FMK and Z-LEHD-FMK, the respective caspase-8 and caspase-9 inhibitor. In addition, western blot analysis revealed a significant augmentation in the protein expression of Bax and attenuation in Bcl-2, suggesting that the celastrol-induced apoptosis acts through both death receptor and mitochondrial pathways. Moreover, western blot analysis on the expression of Rel/NF-κB demonstrated that the celastrol-mediated apoptosis on HaCaT cells was associated with the inhibition of the NF-κB pathway. Taken together, the present project has for the first time identified celastrol as a naturally occurring compound with potent apoptogenic action on cultured human keratinocytes, rendering it a promising candidate for further development into an anti-psoriatic agent.

Topical delivery for the treatment of psoriasis

IMPORTANCE OF THE FIELD

Psoriasis is one of the most common human skin diseases. Topical therapy forms the cornerstone in the management of mild-to-moderate psoriasis. Topical therapies are also used as adjunctive to systemic therapy in moderate and severe forms of the disease.

AREAS COVERED IN THIS REVIEW

In this review, an overview of psoriasis pathogenesis, new topical medications for psoriasis, new targets and molecules, combination topical therapies and combination of topical and phototherapy is provided. Over the past decade several efficacious and acceptable treatment options have emerged from the age-old therapies. The development of sophisticated formulation options has led to an enhancement in the rate and extent of drug delivery across the skin, increasing therapeutic value and improving patient compliance.

WHAT THE READER WILL GAIN

Readers will learn about monotherapy and combination topical products as well as new topical drug delivery technology to achieve optimal clinical outcomes. This review will highlight the need to generate more dermal pharmacokinetic data for better understanding of the impact of formulation change on skin pharmacokinetics to help design improved topical drug delivery systems.

TAKE HOME MESSAGE

New topical formulations have the potential to achieve better efficacy with improved safety profile.

Topical treatment of psoriasis

IMPORTANCE OF THE FIELD

The majority of patients with psoriasis can be safely and effectively treated with topical therapy alone, either under the supervision of a family physician or dermatologist. For those requiring systemic agents, topical therapies can provide additional benefit. Optimal use of topical therapy requires an awareness of the range and efficacy of all products.

AREAS COVERED IN THIS REVIEW

The review covers the efficacy and role of topical therapies including emollients, corticosteroids, vitamin D analogs, calcineurin inhibitors, dithranol, coal tar, retinoids, keratolyics and combination therapy. The report was prepared following a PubMed and Embase literature search up to April 2010.

WHAT THE READER WILL GAIN

The paper provides a broad review of the relevant topical therapeutic options available in routine clinical practice for the management of psoriasis and a recommendation for selection of treatment.

TAKE HOME MESSAGE

Topical therapies used appropriately provide a safe and effective option for the management of psoriasis. An awareness of the available products and their efficacy is key to treatment selection and patient satisfaction.

Psoriasis exacerbation after hormonotherapy in prostate cancer patient-Case report

Psoriasis, as the most common inflammatory skin disorder, affects about 2-3% of the world's population. Many non-dermatological conditions have been linked with psoriasis, including cardiovascular diseases, depression, inflammatory bowel disorders, and some cancers, i.e. lung, colon and kidney cancers. Among systemic factors are endocrine and metabolic disturbances as well as many drugs. Erythrodermic psoriasis, the most severe form of the disease, is characterized by diffuse erytrema and scaling, often accompanied by fever, chills, and malaise. A 57-year-old Caucasian man was admitted for curative radiation therapy of adenocarcinoma of the prostate after 3 months of initial hormonal therapy. The management comprised the combined androgen blockade (CAB). On admission the patient reported escalation of psoriasis symptoms, which he had been treated for since 2002. Due to a mild course of the disease he had not required any systemic treatment ever before, even during aggravation periods. The last exacerbation started appearing a month after hormonal therapy implementation. The cutaneous eruptions, already existing, become larger with new foci revealing, mainly on upper and lower limbs. During radiotherapy planning, there appeared a diffuse erythema and scaling on hands and feet with accompanying pruritis. We decided to start the previously planned radiation therapy which included the prostate gland with 1.5 cm margin and provided for the total dose of 72 Gy in 36 fractions. The irradiation was conducted with the four-field technique using a megavoltage linear accelerator. During radiotherapy we photo-documented skin lesions. To our best knowledge hormone therapy (androgen deprivation) of prostate cancer patients has not been reported as an aggravating factor. Thus, the aim of our work is to present the case of a prostate cancer patient who experienced psoriasis exacerbation after implementation of hormonal blockade as a neoadjuvant oncological treatment.

HLA allele associations and V-beta T-lymphocyte expansions in patients with psoriasis, harboring toxin-producing Staphylococcus aureus

HLA alleles have been associated with psoriasis. Toxin-producing strains of Staphylococcus aureus behave as superantigens, and if present in patients, might play a role in the exacerbation of psoriatic lesions by activating certain V-beta (V beta) T-lymphocyte subsets. Allele frequencies in 22 patients and 22 controls (alleles determined by DNA/SSP typing) were used to calculate a relative risk of $4.7$ ($P < .05$) for HLA-Cw6. S aureus was isolated from the throat of 11 patients. Enterotoxins A and C were detected by agglutination in the culture filtrate of one isolate. The enterotoxin A and/or C genes were detected by PCR in 9 isolates, and transcripts were detected by RT-PCR in 7 of them. None of the isolates from controls harbored enterotoxin genes. V beta expansions were detected by RT-PCR in all 22 patients. Low or no V beta expansions were obtained in controls. The association of HLA-Cw6 with psoriasis in Lebanese concurs with that reported for other ethnic groups. Toxin-producing isolates that colonize patients might play a role in the exacerbation of psoriatic lesions.

Sulfasalazine and pentoxifylline in psoriasis: a possible safe alternative

BACKGROUND

Conventional therapy of extensive psoriasis is effective but has complications. Biologics are safer but expensive.

OBJECTIVE

To assess the efficacy of sulfasalazine and pentoxifylline, which have TNF antagonizing and anti-proliferative action in the treatment of psoriasis.

METHODS

In this randomized controlled trial, 32 patients with extensive psoriasis were divided into four groups: group A received sulfasalazine; group B received pentoxifylline; group C received both drugs; and group D received methotrexate. The Psoriasis Area and Severity Index (PASI) score was done at weeks 0, 2, 4, 6 and 8.

RESULTS

A significant reduction in PASI score occurred in groups C and D (p = 0.043 and 0.018, respectively). A significantly higher percentage of PASI score reduction occurred in group D compared with groups A, B and C (p = 0.006, 0.003 and 0.030, respectively). An excellent response occurred in one patient (14.3%) in group D. A very good response occurred in two patients (22.2%) in group C, and in five patients (71.4%) in group D. A moderate response occurred in three patients (37.5%) in group A, one patient (12.5%) in group B, and one patient (14.3%) in group D.

CONCLUSION

Although incomparable to methotrexate, combined sulfasalazine and pentoxifylline produced a good response in cases of extensive psoriasis. Multicentre studies are needed to validate these results.

Drug-Induced Psoriasis: An Evidence-Based Overview and the Introduction of Psoriatic Drug Eruption Probability Score

Psoriasis is a common skin disorder that needs a long-term management, not only because, of its prevalence but also because of the profound impact it can have on patients quality of life. Drugs may result in exacerbation of a preexisting psoriasis, in induction of psoriatic lesions on clinically uninvolved skin in patients with psoriasis, or in precipitation of the disease in persons without family history of psoriasis or in predisposed individuals. The knowledge of the drugs that may induce, trigger, or exacerbate the disease is of primary importance in clinical practice. By reviewing the literature, there are many reports on drug-induced psoriasis, but the data are not univocal. We propose, when possible, the use of a probability score from the authors to obtain a better classification and further understanding of drug-induced psoriasis.

The methylation pattern of p16INK4a gene promoter in psoriatic epidermis and its clinical significance

BACKGROUND

Alteration of the p16INK4a gene by epigenetic changes has been described in some hyperproliferative skin diseases, but its importance in psoriasis has not yet been established.

OBJECTIVES

To investigate the methylation status of the p16INK4a gene in psoriatic epidermis, its clinical significance and the possible epigenetic mechanisms of psoriasis.

METHODS

DNA and RNA specimens were obtained from the lesional epidermis of 56 patients with plaque psoriasis. Methylation-specific polymerase chain reaction (PCR) and DNA sequencing were used to detect the density and sites of methylation in the p16INK4a promoter region. The reverse transcription-PCR technique was applied to detect the mRNA expression of p16INK4a.

RESULTS

p16INK4a gene promoter methylation was shown in 17 of 56 (30%) patients with psoriasis. Psoriasis Area and Severity Index scores in patients showing methylation were higher than in those who did not (P<0.05). The mRNA expression level of p16INK4a in the methylated group was significantly lower than in the unmethylated group (t=2.515, P=0.015). In the methylated group, about 50% of the CpG islands were methylated in the promoter region.

CONCLUSIONS

Overall, methylation of the p16INK4a gene promoter is found in psoriatic epidermis, which is associated with the mRNA level of p16INK4a expression and activity of the disease. These data indicate that methylation of the p16INK4a promoter may play a potential role in the pathogenesis of psoriasis.

XP-828L (Dermylex), a new whey protein extract with potential benefit for mild to moderate psoriasisThis article is one of a selection of papers published in this special issue (part 1 of 2) on the Safety and Efficacy of Natural Health Products

Natural health products (NHPs) or complementary and alternative medicine (CAM) are commonly used to prevent disorders or support the usual treatments of many diseases. XP-828L, a whey protein extract, has demonstrated potential benefits for the treatment of mild to moderate psoriasis. The aim of this study was to analyze further clinical data that demonstrated the clinical benefits and safety of the XP-828L in patients with psoriasis and the potential mechanism of action of this product in vitro. Oral administration (2.5 g, twice a day, over 112 days) of XP-828L in 42 human subjects with mild to moderate psoriasis improved their PGA scores (physician’s global assessment). Moreover, no significant changes in haematology or hepatic and renal parameters were observed throughout the study period, indicating the safety of the product. In vitro experiments showed that XP-828L decreased the proliferation of concanavalin A (ConA)-stimulated murine splenocytes and their production of interleukin (IL)-2 and interferon (IFN)-γ. Although the in vivo mechanism of action of XP-828L remains unknown, XP-828L represents an NHP to be used as an alternative or concomitant treatment for mild to moderate psoriasis and potentially for other immune-mediated diseases.

Mimicking cell-cell interactions at the biomaterial-cell interface for control of stem cell differentiation

The ability to regulate stem cell proliferation and differentiation has relevance in numerous medical applications, including medical devices, tissue engineering, and regenerative medicine. To control cellular behavior at the biomaterial or scaffold interface, many studies have employed surface modifications that mimic the extracellular matrix. Strikingly absent is the immobilization of cell-surface ligands to the biomaterial surface. One cell-to-cell signaling pathway that has been shown to regulate tissue development and stem cell fate is the Notch pathway. Recently, the Notch signaling pathway was identified as a key regulator of epithelial differentiation. Utilizing this knowledge, we applied an affinity immobilization scheme designed to attach and orient the Notch ligand, Jagged-1, in an active conformation on a biomaterial surface. When epithelial stem cells were plated on the bound ligand, the Notch/CBF-1 signaling pathway was stimulated and the cells upregulated both intermediate- and late-stage differentiation markers. In addition, the ligand promoted tight clustering and extensive stratification. Soluble Jagged-1 showed no Notch/CBF-1 signaling and very little, if any, cell differentiating activity. The high potency of bound Jagged-1 suggests that modification of a surface with a Notch ligand presents a powerful method to control stem cell differentiation at the cell-biomaterial interface.

Consistent control of psoriasis by continuous long-term therapy: the promise of biological treatments

Psoriasis is a chronic, incurable disease that frequently requires long-term treatment. Although many patients benefit from effective traditional systemic therapies, namely methotrexate, cyclosporin, retinoids and fumaric acid esters, and some patients achieve long-term disease control, unrestricted long-term administration is not recommended due to the potential for cumulative toxicity. In order to diminish the risk of toxicity, physicians have adopted various treatment approaches (e.g. rotational, sequential, intermittent, and combination). However, these approaches may not provide continuous disease control or a stable treatment regimen. The recent advent of targeted biological therapeutics such as etanercept, infliximab, adalimumab, alefacept and efalizumab may offer physicians and their patients treatment options with improved safety profiles that may permit continuous disease control.

Quality of life in patients with psoriasis

Psoriasis is one of the prevalent skin conditions in the United States. This chronic condition has a significant negative impact on patients' quality of life. Psoriasis has been linked to the depression and suicidal tendencies in the patients. The costs associated with decrements in quality of life, lost productivity, and work absenteeism may be enormous, increasing overall costs associated with the disease management. This review attempts to outline different quality of life measures available for psoriasis and describes their use in studies examining patient reported outcomes associated with pharmacological interventions for psoriasis. Factors associated with quality of life in psoriasis patients are described. It further describes physician's role in the psoriasis management to improve patients' overall well-being.

The cost-effectiveness and cost of treatment failures associated with systemic psoriasis therapies

BACKGROUND

Psoriasis is difficult at times to treat and treatment failures are not uncommon regardless of approach. With the advent of expensive biologic therapies for psoriasis there is increasing discussion on the cost efficacy of a given systemic or biologic agent. An alternative and overlooked aspect of cost efficacy is the cost that accrues from treatment failures.

METHODS

We review the literature and develop a model to analyze the cost-effectiveness and the cost of treatment failures per success for various systemic psoriasis agents using a 12-week treatment period.

RESULTS

For continuous-dose agents, the cost-effectiveness results are: methotrexate $623, acitretin $2729, cyclosporine $2969, nUVB $3692, PUVA $4668, etanercept $16 312, and efalizumab $17 196. The cost of expected treatment failures to achieve one success for the same agents were: methotrexate $187, cyclosporine $505, PUVA $767, nUVB $1034, acitretin $1310, etanercept $8319, and efalizumab $12 897.

CONCLUSIONS

Methotrexate appears to be the most cost-effective agent for the treatment of severe psoriasis. However, greater efficacy can be achieved with cyclosporine and PUVA, albeit at a greater cost. Because of the high cost of treatment failures, access to a wide array of therapies and combination regimens should not be discouraged by physicians or insurers.

Expression profiles of elastase1 (NvElastaseI) and secretory leukocyte protease inhibitor (NvSLPI) during forelimb regeneration in adult Notophthalmus viridescens suggest a role in epithelial remodeling and delamination

Extracellular proteases and their inhibitors may regulate a number of important processes involved in forelimb regeneration in the adult newt, including epithelial remodeling, breakdown of extracellular matrix, and dedifferentiation. We have identified a newt homologue of human ElastaseI (NvElastaseI) and its potential inhibitor, SLPI (NvSLPI), and evaluated their spatial and temporal expression during limb regeneration. NvElastaseI is upregulated early in regeneration and is associated with subdermal and wound epithelial cells, suggesting an involvement in wound healing and the generation of the wound epithelium. Up until 15 days post-amputation, NvElastaseI is also scattered throughout the developing blastema and may have a role in the dedifferentiation of stump tissues. NvSLPI is found at the interface between the intact skin and the wound epithelium, and may limit NvElastaseI activity. NvSLPI is also expressed in dermal glands, and is likely involved in anti-microbial activity or function. Quite apart from regeneration, complementary patterns of expression of NvElastaseI and NvSLPI are associated with newt epithelial sloughing.

A new formulation of an occlusive dressing containing betamethasone valerate 0.1% in the treatment of mild to moderate psoriasis

BACKGROUND

Betamethasone valerate (BMV) is a medium-potency corticosteroid commonly used for the treatment of chronic psoriasis. Although occlusion has been shown to enhance the efficacy of BMV treatment, no ready-to-use occlusive BMV formulation is currently approved for the market.

METHODS

Forty-two patients with mild to moderate psoriasis and with symmetrical lesions were treated with BMV 0.1% tape and BMV 0.12% cream for 30 days in a half-side distribution. Both treatments resulted in a significant clinical improvement. Efficacy and tolerability were evaluated by comparison of pre-treatment and post-treatment psoriasis area and severity index and self-administered psoriasis area and severity index scores, and by comparison of the changes from baseline in clinical appearance and hydration.

RESULTS

Lesions treated with BMV 0.1% tape showed higher reductions from baseline in the psoriasis area and severity index and the self-administered psoriasis area and severity index scores (61.7% and 59.3%, respectively), compared with lesions treated with BMV 0.12% cream (39.5% and 34.0%, respectively). No serious local or systemic treatment-related adverse effects were reported.

CONCLUSIONS

Our results indicate a higher efficacy of BMV 0.1% tape compared with BMV 0.12% cream in the treatment of mild to moderate chronic plaque psoriasis.

Medication-related factors affecting health care outcomes and costs for patients with psoriasis in the United States

BACKGROUND

The impact of psoriasis medication therapy on costs and patient outcomes in large nationally representative samples needs further examination.

OBJECTIVE

This study examined the association between factors related to medication use, health status, and health care costs associated with psoriasis in the United States.

METHODS

A cross-sectional cohort study was performed using the 2000 Medical Expenditure Panel Survey database. Information on health care service use, health status (EuroQol-5D instrument), and patient demographics were obtained from the database representing approximately 1.1 million patients with psoriasis. EuroQol was used in the Medical Expenditure Panel Survey.

RESULTS

Weighted multiple linear regression analysis indicated that use of topical corticosteroid therapy was associated with a decrease in psoriasis-specific health care costs (53.2% lower than average costs vs patients using no medications, P = .022) and better health status (34.0% higher than average scores vs patients using no medications, P = .006).

CONCLUSIONS

We observed an association with topical corticosteroids for treatment of psoriasis on health care outcomes and costs.

Oral pimecrolimus in the treatment of moderate to severe chronic plaque-type psoriasis: a double-blind, multicentre, randomized, dose-finding trial

BACKGROUND

There is a need for safe and effective alternative treatments for patients with moderate to severe psoriasis.

OBJECTIVES

Pimecrolimus is a calcineurin inhibitor that is being investigated in oral form for the treatment of psoriasis.

PATIENTS AND METHODS

A double-blind, randomized, parallel-group, dose-finding study was performed. Healthy adult outpatients with moderate to severe chronic plaque-type psoriasis (n = 143) were randomized to receive oral placebo or pimecrolimus 10 mg, 20 mg or 30 mg twice daily (b.d.) for 12 weeks.

MAIN OUTCOME MEASURES

The Psoriasis Area and Severity Index (PASI) was used to assess clinical severity of psoriasis. Results were analysed at weeks 7 (primary endpoint) and 13. Safety was assessed by monitoring all adverse events, laboratory investigations (blood chemistry, urinalysis, haematology) and physical examinations.

RESULTS

The change from baseline in PASI at week 7 showed a dose-dependent effect. The differences between each of the two higher doses of pimecrolimus and placebo were statistically significant (P < 0.001; ANOVA). The mean percentage decreases from baseline in PASI in the placebo group and pimecrolimus 10 mg, 20 mg and 30 mg b.d. groups at week 7 were 3.1%, 22.2%, 51.3% and 54.0%, respectively. Most adverse events were of mild or moderate severity. The only adverse event to show a dose-response relationship was a transient feeling of warmth. No clinically relevant effects on laboratory parameters were observed, and no increase in skin infection with pimecrolimus was seen.

CONCLUSIONS

Oral pimecrolimus produces a dose-dependent reduction in psoriasis severity, with doses of 20 mg and 30 mg b.d. being the most effective and well tolerated.

Integrating Biologic Agents into Management of Moderate-to-Severe Psoriasis: A Consensus of the Canadian Psoriasis Expert Panel

BACKGROUND

Approximately 2% of people worldwide have psoriasis, with as many as 1 million people with psoriasis in Canada alone.1,2 The severity of psoriasis ranges from mild to severe. It can lead to substantial morbidity and psychological stress and have a profound negative impact on patient quality of life.3,4 Although available therapies reduce therapies reduce the extent and severity of the disease and improve quality of life,3 reports have indicated a patient preference for more aggressive therapy and a dissatisfaction with the effectiveness of current treatment options.5

OBJECTIVE

A Canadian Expert Panel, comprising Canadian dermatologists, convened in Toronto on 27 February 2004 to reach a consensus on unmet needs of patients treated with current therapies and how to include the pending biologic agents in and improve the current treatment algorithm for moderate-to-severe psoriasis. Current treatment recommendations suggest a stepwise strategy starting with topical agents followed by phototherapy and then systemic agents.3,6,7 The Panel evaluated the appropriate positioning of the biologic agents, once approved by Health Canada, for the treatment of moderate-to-severe psoriasis.

METHODS

The Panel reviewed available evidence and quality of these data on current therapies and from randomized, controlled clinical trials.8-14 Subsequently, consensus was achieved by small-group workshops followed by plenary discussion.

RESULTS

The Panel determined that biologic agents are an important addition to therapies currently available for moderate-to-severe psoriasis and proposed an alternative treatment algorithm to the current step wise paradigm.

CONCLUSION

The Panel recommended a new treatment algorithm for moderate-to-severe psoriasis whereby all appropriate treatment options, including biologic agents, are considered together and patients' specific characteristics and needs are taken into account when selecting the most appropriate treatment option.

Topical delivery of cyclosporin A: an in vitro study using monoolein as a penetration enhancer

Topical delivery of cyclosporin A (CysA) is of great interest for the treatment of autoimmune skin disorders, but it is frequently ineffective due to poor drug penetration in the skin. The present study was aimed at investigating whether the presence of monoolein (a lipidic penetration enhancer) in a preparation of propylene glycol can improve CysA delivery to the skin. CysA was incorporated in a propylene glycol preparation containing 5-70% (w/w) of monoolein. The topical (to the skin) and transdermal (across the skin) delivery of CysA were evaluated in vitro using porcine ear skin mounted in a Franz diffusion cell. CysA was quantified by UV-HPLC. At 5%, monoolein increased only the transdermal delivery of CysA. At 10%, it increased both topical and transdermal delivery. When the concentration of monoolein was further increased (20-70% w/w), an interesting phenomenon was observed: the topical delivery of CysA was still elevated but its transdermal delivery was substantially reduced. It was concluded that monoolein (in propylene glycol formulations) can promote the topical delivery of CysA, with reduced transdermal delivery.

TISSUE DISTRIBUTION AND RECEPTOR-MEDIATED CLEARANCE OF ANTI-CD11A ANTIBODY IN MICE

Efalizumab (Raptiva) is a humanized monoclonal antibody specific for CD11a, the alpha-chain component of the lymphocyte function-associated antigen 1. In humans, the rate of efalizumab elimination from serum was related to the level of CD11a cell surface expression. These data suggested a role for the CD11a receptor, itself, in efalizumab clearance. Recently, we conducted a series of in vitro studies that suggested a role for CD11a-expressing T cells in efalizumab clearance as mediated by cellular internalization and lysosome-mediated degradation (Coffey et al., 2004). To further study the mechanism of anti-CD11a clearance in vivo, we assessed the tissue distribution, cellular internalization, and subcellular localization of a rat anti-mouse CD11a monoclonal antibody in various tissues in mice. Anti-CD11a antibody primarily distributed to leukocytes and macrophages in the peripheral blood, spleen, and liver, with uptake in the lymph nodes and bone marrow after 72 h. At least a portion of the antibody was internalized and cleared by peripheral blood mononuclear cells, lymphocytes, and splenocytes in a time-dependent manner in vivo. Internalized antibody costained with LysoTracker Red, suggesting that it was transported to lysosomes for degradation. Together, these data suggest that one clearance mechanism for anti-CD11a antibody in vivo is via receptor-mediated internalization and lysosomal degradation by CD11a-expressing cells and tissues.

Topical halobetasol propionate in the treatment of plaque psoriasis: a review

Halobetasol propionate (HP) 0.5% ointment and cream are class I topical corticosteroids. We review the efficacy and tolerability of HP for treatment of plaque psoriasis in the English language literature. The efficacy of HP ointment and cream is consistently superior to other super-potent topical corticosteroids. Local adverse events associated with topical HP are similar to those experienced with other super-potent corticosteroids. Combination therapy with calcipotriene (calcipotriol) and tazarotene appears to be superior to monotherapy with topical HP.

p16 expression in psoriatic lesions following therapy with propylthiouracil, an antithyroid thioureylene

Plaque formation is a characteristic finding in patients with psoriasis and reflects cytokine-induced keratinocyte proliferation and/or impaired apoptosis of keratinocytes. Antithyroid thioureylenes such as propylthiouracil (PTU) and methimazole (MMI) are effective in the treatment of plaque psoriasis. Following PTU and MMI treatment, proliferative cell nuclear antigen (PCNA) expression is significantly reduced, suggesting that these medications have an antiproliferative effect. p16 is an antiapoptotic protein that is present in relative abundance in psoriatic plaques and is believed to play a potential role in the persistent senescence and impaired apoptosis of the keratinocytes in the plaque. This study examined p16 expression in biopsy samples of eight patients with plaque psoriasis given 300 mg of propylthiouracil in divided doses for 3 months. Despite significant clinical and histological improvement with PTU treatment, p16 expression was essentially unchanged, suggesting that the beneficial effect of PTU in psoriasis is not mediated through a decrease in p16 expression. The effect of PTU on other antiapoptotic proteins such as bcl-xL remains to be determined.

A 50% reduction in the Psoriasis Area and Severity Index (PASI 50) is a clinically significant endpoint in the assessment of psoriasis

A 75% reduction in the Psoriasis Area and Severity Index (PASI) score (PASI 75) is the current benchmark of primary endpoints for most clinical trials of psoriasis. Many consider this endpoint to be too stringent as it places potentially useful therapies at risk of failing to demonstrate efficacy. We hypothesized that a 50% reduction in the PASI score (PASI 50) represents a meaningful change in a person's life and thus is a better primary endpoint. To test this hypothesis, we analyzed PASI scores, quality of life (QoL) data, and desired re-treatment scores from a number of clinical trials in addition to studying individual elements that make up the PASI. This analysis shows (1). the PASI score is not linearly reflective of psoriasis severity (eg, a reduction in area of 95% without a change in redness, scaliness, and induration translates to only a 66% reduction in PASI); conversely, a drop in erythema, scale, and induration from an average of 3 to 1 would not lead to a 75% reduction in PASI; (2). treatment with methotrexate, an effective psoriasis therapy, more frequently reaches PASI 50 than PASI 75 as evidenced by a recent open trial in which 63% of patients achieved PASI 50 versus 26% achieving PASI 75; (3). improvement in QoL exists at PASI 50, using the Dermatology Quality of Life Index, as documented in several recently completed large clinical trials; (4). patients achieving PASI 75 frequently defer therapy until they are well below PASI 50; a clinical trial where retreatment was patient initiated showed patients did not re-treat until their PASI dropped to an average of 20% improvement from baseline; and (5). effective, meaningful therapies are consistently differentiated from placebo at PASI 50 as evidenced by histologic and photographic parameters of clinical trials of alefacept, efalizumab, and etanercept. We conclude that PASI 50 equates to a clinically meaningful improvement in psoriasis and represents a discerning primary endpoint.

Leflunomide in the treatment of psoriasis: results of a phase II open trial

BACKGROUND

Psoriasis is recognized as the most prevalent T-cell-mediated inflammatory disease in humans, with predominantly activated T-helper (Th) 1 cell effectors. Leflunomide exerts its anti-inflammatory activities by preventing the generation of proinflammatory Th1 effectors and promoting Th2 cell differentiation.

OBJECTIVES

To determine the safety and efficacy of leflunomide in patients with moderate to severe plaque-type psoriasis.

METHODS

In an open-label phase II trial, eight patients with psoriasis received oral leflunomide 20 mg daily for 12 weeks. Patients were evaluated for improvement in psoriasis, quality of life, histological changes and toxicity.

RESULTS

Antipsoriatic effects were obtained in all but two patients. A significant decrease was observed in the mean +/- SD Psoriasis Area and Severity Index score, from 20.08 +/- 6.85 before treatment to 12.51 +/- 11.83 after (P = 0.03). The antipsoriatic efficiency was confirmed histologically, with a significant mean +/- SD decrease in epidermal thickness, from 0.73 +/- 0.19 micro m before to 0.31 +/- 0.16 microm after (P = 0.01). The quality of life score showed an improvement, from 8.58 +/- 2.38 (mean +/- SD) before to 5.33 +/- 1.95 after (P = 0.02). The treatment was well tolerated; adverse reactions primarily consisted of transitory gastrointestinal events.

CONCLUSIONS

Our data suggest that leflunomide for plaque-type psoriasis is a safe and clinically effective option as monotherapy. However, double-blind, placebo-controlled studies are needed.

Tratamento sistêmico da psoríase - Parte I: metotrexato e acitretina

Embora a fisiopatologia da psoríase ainda não esteja totalmente esclarecida e permaneçam dúvidas quanto à natureza dos antígenos que levam à ativação do linfócito T e quanto ao papel dos mecanismos reguladores dos surtos e da resolução da inflamação, são inegáveis os avanços terapêuticos das últimas décadas. Além do surgimento de novos medicamentos, a melhor utilização de tratamentos clássicos e a valorização do impacto da terapêutica na qualidade de vida dos pacientes têm contribuído para a diminuição dos índices de morbidade da doença. Este artigo de EMC-D aborda a utilização de metotrexato e acitretina no tratamento da psoríase. A utilização de outros imunomoduladores e de terapias biológicas será objeto de próximo capítulo.

Serum TNF-alpha in psoriasis after treatment with propylthiouracil, an antithyroid thioureylene

Background

Tumor necrosis factor-α (TNF-α) and its receptors play important roles in the development and persistence of psoriatic plaques. The antithyroid thioureylenes, propylthiouracil and methimazole, are effective in the treatment of patients with psoriasis with a significant number of patients showing clearing or near clearing of their lesions after a several weeks of treatment.

Methods

The present study examined the effect of treatment with propylthiouracil, given in a dose of 100 mg every 8 hours for 3 months, on the serum levels of TNF-α in 9 patients with plaque psoriasis.

Results

Propylthiouracil therapy did not result in a significant decline in serum TNF-α concentrations.

Conclusions

The findings suggest that the therapeutic effect of propylthiouracil in psoriasis appears not to be related to any change in the concentration of TNF-α but occurs via an anti-proliferative mechanism as we have previously speculated.

Anti-thyroid thioureylenes in the treatment of psoriasis

Psoriasis is a common skin disorder associated with significant morbidity. Many agents are used in the medical management of this debilitating condition with the newer anti-cytokine agents being the most recent addition to the pharmacological armamentarium to battle the disorder. Cost concerns are very important with the newer "biologic" treatments costing in excess of 10,000 US dollars annually. The need for cheaper, orally administered agents is therefore imperative. This paper addresses the potential role of anti-thyroid thioureylenes, propylthiouracil and methimazole, in the treatment of psoriasis and reviews the possible mechanism of action of these drugs in this disorder. It is hypothesized that the beneficial effect of anti-thyroid thioureylenes in psoriasis is linked to their effect as anti-proliferative agents as reflected by significant decrease in markers of cellular proliferation such as proliferative cell nuclear antigen in biopsy specimens after treatment with these drugs. Propylthiouracil has been shown to bind to the hepatic T 3 receptor and it is possible that propylthiouracil (6-n-propyl-2-thiouracil) binding to the ligand-binding site normally occupied by T 3 impairs transcription by inactivating the effect of T 3 as well as by squelching retinoic X receptor heterodimer formation with other receptors of the steroid receptor superfamily such as the peroxisome proliferator-activated receptor, retinoic acid receptor and vitamin D receptors.

Improved health-related quality of life following a randomized controlled trial of alefacept treatment in patients with chronic plaque psoriasis

BACKGROUND

Psoriasis has a negative impact on patients' quality of life. Treatment strategies should address both the cutaneous manifestations of the disease and their impact on quality of life.

OBJECTIVES

To evaluate the effect of alefacept on quality of life in 553 patients with chronic plaque psoriasis.

METHODS

In this multicentre, double-blind, parallel-groups study, patients were randomized to receive alefacept for two courses, alefacept in course 1 and placebo in course 2, or placebo in course 1 and alefacept in course 2. In each course, alefacept 7.5 mg or placebo was administered once weekly by 30-s intravenous injection for 12 weeks followed by 12 weeks of observation. The Dermatology Life Quality Index (DLQI), Dermatology Quality of Life Scales (DQOLS) and Short Form-36 Health Survey (SF-36) were administered at baseline, 2 weeks after the last dose in both courses, at the beginning of course 2, and at the end of the observation period in both courses.

RESULTS

In course 1, alefacept significantly reduced (improved) mean DLQI scores compared with placebo: 4.4 vs. 1.8 at 2 weeks after the last dose (P<0.0001) and 3.4 vs. 1.4 at 12 weeks after the last dose (P<0.001). Patients who received two courses of alefacept experienced additional enhancement of quality of life measures during the second course. Similar results were observed for the DQOLS. The SF-36 survey confirmed that alefacept had no negative impact on general quality of life.

CONCLUSIONS

Alefacept improved quality of life in patients with chronic plaque psoriasis and maintained this benefit for at least 12 weeks following cessation of treatment. A second course of alefacept provided additional quality of life benefit.

CD1a expression in psoriatic skin following treatment with propylthiouracil, an antithyroid thioureylene

BACKGROUND

The antithyroid thioureylenes, propylthiouracil (PTU) and methimazole (MMI), are effective in the treatment of patients with plaque psoriasis. The mechanism of action of the drugs in psoriasis is unknown. Since the drugs reduce circulating IL-12 levels in patients with Graves' hyperthyroidism, the effect of propylthiouracil on CD1a expression in psoriatic lesions was examined in biopsy samples of patients with plaque psoriasis. CD1a is a marker of differentiated skin antigen presenting cells (APC, Langerhans cells). Langerhans cells and skin monocyte/macrophages are the source of IL-12, a key cytokine involved in the events that lead to formation of the psoriatic plaque.

METHODS

Biopsy specimens were obtained from six patients with plaque psoriasis who were treated with 300 mg propylthiouracil (PTU) daily for three months. Clinical response to PTU as assessed by PASI scores, histological changes after treatment, and CD1a expression in lesional skin before and after treatment were studied.

RESULTS

Despite significant improvement in clinical and histological parameters the expression of CD1a staining cells in the epidermis did not decline with propylthiouracil treatment.

CONCLUSIONS

It appears that the beneficial effect of propylthiouracil in psoriasis is mediated by mechanisms other than by depletion of skin antigen-presenting cells.

Comparative tolerability of systemic treatments for plaque-type psoriasis

Psoriasis is a chronic, debilitating skin condition that affects millions of people and is attributed to both genetic and environmental factors. Topical therapy is generally considered to be the first-line treatment of psoriasis. However, many patients do not respond to topical therapy or have disease so extensive that topical therapy is not practical. For these patients, systemic therapy is indicated. Presently, there are four available systemic treatments, psoralen with ultraviolet A (PUVA), methotrexate, oral retinoids (acitretin), and cyclosporin. Unfortunately, all of these treatments have significant potential adverse effects. PUVA may acutely cause nausea, pruritus and sunburn. More chronic and concerning is the development of PUVA lentigines, ocular complications and skin cancer. Non-melanoma skin cancer has been directly linked to PUVA; however, the association with melonoma is more elusive. Methotrexate use most notably carries the risk of hepatic fibrosis and cirrhosis, which is not always evident on liver function tests. Other more rare, but potentially life-threatening adverse effects include pancytopenia, lymphoproliferative disorders and acute pneumonitis. The addition of folic acid may help to reduce the risk of increasing liver enzymes and haematological toxicity seen in those taking methotrexate. Both methotrexate and oral retinoids are teratogenic and should never be used in pregnancy. Oral retinoids are probably the least effective available systemic medication for the treatment of plaque psoriasis. The effects are improved with the addition of other systemic therapies. Acitretin has replaced the formerly used etretinate primarily because of the significantly shorter half-life. The adverse effects are generally mild and reversible, making the drug fairly safe for long-term use. The most commonly seen adverse effects include elevated serum lipids, generalised xerosis and alopecia. Bony abnormalities, while somewhat controversial, have also been described and include diffuse idiopathic skeletal hyperostosis, skeletal calcifications and osteoporosis. Cyclosporin is the most recently approved systemic medication for plaque psoriasis. The nephrotoxicity associated with the use of cyclosporin can be minimised when used in lower doses and for a limited duration. Hypertension is usually mild and can be seen in up to about one-third of patients receiving long-term therapy. Cutaneous and internal malignancies have also been reported with cyclosporin and tend to be correlated with duration of treatment. In this review, we will examine the potential adverse effects with these US Food and Drug Administration-approved treatments in adults, with specific emphasis on the controversies that surround long-term therapy with these agents and their cumulative adverse effects.