Calcipotriol versus coal tar: a prospective randomized study in stable plaque psoriasis

Topical Treatment for the Management of Mild-to-Moderate Psoriasis: A Critical Appraisal of the Current Literature

Several comprehensive and updated guidelines are available on the management of psoriasis with systemic treatments. However, there is a lack of updates in recommendations and guidelines on topical treatments, particularly regarding the latest evidence and developments in treatment formulations. Consequently, a comprehensive literature review on this topic, considering the continuous evolution of knowledge and evaluation of the relevance of the available literature evidence, represents a current need to improve the topical management of psoriasis. This study critically appraises the available literature on all topical treatments of psoriasis from the past 20 years to address some relevant issues, such as the vehicle associated with the highest effectiveness, the best vehicle for improving patient adherence, and the best strategy in terms of efficacy and safety for long-term treatment. The greater effectiveness of the foam formulation was demonstrated for calcipotriene/betamethasone dipropionate (Cal/BD) administration compared with the gel and ointment. Without a direct comparison, matching-adjusted indirect comparison analyses support the superiority of the foam versus the cream overall. In addition, the reduced treatment period required by the Cal/BD foam (4 weeks) may favor this formulation over cream (8 weeks). The literature evidence, supported by a broad clinical experience, reported high rates of acceptability and adherence for the foam vehicle. A growing consensus is shared among dermatologists sustaining the proactive approach as the best option for the long-term topical treatment of psoriasis in adults. The Cal/BD foam is the only treatment for which the approved label allows biweekly maintenance use (proactive management), thus representing the first option for long-term topical treatment.

Systematic literature review of long-term efficacy data for topical psoriasis treatments

OBJECTIVE

To identify long-term efficacy evidence that supports use of topical therapies as regular maintenance therapy in the prevention of psoriasis relapse.

METHODS

A systematic literature review identified clinical trials and observational studies that reported efficacy outcomes for topical psoriasis therapies with treatment durations of at least 12 weeks. For therapies with long-term data, the approved treatment schedules in product labels were reviewed.

RESULTS

Forty-six studies with at least 12-week efficacy outcomes were identified. Eight randomized controlled trials and six observational studies or single-arm open-label studies reported efficacy data for >12-week treatment periods. Most studies used treatment regimens that reflect current standard of care of repeated treatment of relapses. The PSO-LONG study is the only identified randomized controlled trial to have compared regular proactive maintenance use of a topical treatment (calcipotriol/betamethasone foam) with reactive management in response to psoriasis relapses.

CONCLUSIONS

Limited high-quality long-term efficacy data are available for topical psoriasis therapies. While some product labels mention clinical experience of up to 12 months, they do not provide specific recommendations on the optimal long-term regimen. Calcipotriol/betamethasone foam is the only treatment for which the approved label allows either reactive treatment of relapse or regular (twice weekly) maintenance use.

Randomized Placebo Control Study of Metformin in Psoriasis Patients with Metabolic Syndrome (Systemic Treatment Cohort)

BACKGROUND

Psoriasis has been found to be associated with obesity, metabolic syndrome (MS), diabetes, and cardiovascular risk factors. Metformin treatment showed improvement in cardiovascular risk factors and hyperinsulinemia.

OBJECTIVE

To evaluate the efficacy and safety of metformin in psoriasis patients with MS.

MATERIALS AND METHODS

This was a single-center, parallel-group, randomized, open-label study with blinded end point assessment of metformin (1000 mg once daily for 12 weeks; n = 20) and placebo (n = 18) in psoriasis patients with MS. Total sample size was 38 participants.

RESULTS

Statistically significant improvement was observed in mean percentage change in erythema, scaling, and induration (ESI) (P = 0.048) in metformin as compared to placebo while mean percentage change in psoriasis area and severity index (PASI) and physician global assessment (PGA) scores was not significant (PASI - P = 0.215, PGA - P = 0.070). There was a statistically significant difference in percentage of parameters of MS improved following 12 weeks of treatment in metformin (19%) as compared to placebo (8.9%) group (P = 0.046). Statistically significant difference in percentage of patients achieving 75% reduction in ESI scores (P = 0.024). Significant improvement was observed in mean weight, body mass index (BMI), total cholesterol, and low-density lipoprotein (LDL) cholesterol in metformin group as compared to placebo. Improvement in BMI, fasting plasma glucose, serum triglycerides, high-density lipoprotein, LDL, systolic blood pressure, diastolic blood pressure, and total cholesterol was statistically significant in metformin group over the period of 12 weeks. There was no significant difference in adverse events in two groups except weight gain.

CONCLUSION

Metformin has shown improvement in psoriasis and parameters of MS, hence can be used for the benefit of psoriasis patients having MS. Large, controlled studies are needed to confirm.

Topical Therapies in Psoriasis

Topical therapy as monotherapy is useful in psoriasis patients with mild disease. Topical agents are also used as adjuvant for moderate-to-severe disease who are being concurrently treated with either ultraviolet light or systemic medications. Emollients are useful adjuncts to the treatment of psoriasis. Use of older topical agents such as anthralin and coal tar has declined over the years. However, they are cheaper and can still be used for the treatment of difficult psoriasis refractory to conventional treatment. Salicylic acid can be used in combination with other topical therapies such as topical corticosteroids (TCS) and calcineurin inhibitors for the treatment of thick limited plaques to increase the absorption of the latter into the psoriatic plaques. Low- to mid-potent TCS are used in facial/flexural psoriasis and high potent over palmoplantar/thick psoriasis lesions. The addition of noncorticosteroid treatment can also facilitate the avoidance of long-term daily TCS. Tacrolimus and pimecrolimus can be used for the treatment of facial and intertriginous psoriasis. Tazarotene is indicated for stable plaque psoriasis usually in combination with other therapies such as TCS. Vitamin D analogs alone in combination with TCS are useful in stable plaques over limbs and palmoplantar psoriasis. Topical therapies for scalp psoriasis include TCS, Vitamin D analogs, salicylic acid, coal tar, and anthralin in various formulations such as solutions, foams, and shampoos. TCS, vitamin D analogs, and tazarotene can be used in the treatment of nail psoriasis.

Randomized placebo control study of insulin sensitizers (Metformin and Pioglitazone) in psoriasis patients with metabolic syndrome (Topical Treatment Cohort)

Background

Increased prevalence of metabolic syndrome (MS) is observed in psoriasis. Metformin has shown improvement in cardiovascular risk factors while pioglitazone demonstrated anti proliferative, anti-inflammatory and anti angiogenic effects. Study objective is to evaluate the efficacy and safety of Insulin sensitizers (metformin and pioglitazone) in psoriasis patients with metabolic syndrome (MS).

Methods

Single centre, parallel group, randomized, study of metformin, pioglitazone and placebo in psoriasis patients with MS.

Results

Statistically significant improvement was observed in Psoriasis Area and Severity Index (PASI), Erythema, Scaling and Induration (ESI) and Physician global assessment (PGA) scores in pioglitazone (p values – PASI = 0.001, ESI = 0.002, PGA = 0.008) and metformin groups (p values – PASI = 0.001, ESI = 0.016, PGA = 0.012) as compared to placebo. There was statistically significant difference in percentage of patients achieving 75 % reduction in PASI and ESI scores in metformin (p value – PASI = 0.001, ESI = 0.001) and pioglitazone groups (p vaue – PASI = 0.001, ESI = 0.001). Significant improvement was observed in fasting plasma glucose (FPG) and triglycerides levels in metformin and pioglitazone arms. Significant improvement was noted in weight, BMI, waist circumference, FPG, triglycerides and total cholesterol after 12 weeks of treatment with metformin while pioglitazone showed improvement in FPG, triglyceride levels, systolic blood pressure (SBP), diastolic blood pressure (DBP), total cholesterol and LDL cholesterol levels. There was no difference in pattern of adverse drug reaction in three groups.

Conclusion

Insulin sensitizers have shown improvement in the parameters of MS as well as disease severity in psoriasis patients.

Trial registration

CTRI Registration Number: CTRI/2011/12/002252. Registered on 19/12/2011.

An open label prospective randomized trial to compare the efficacy of coal tar-salicylic Acid ointment versus calcipotriol/betamethasone dipropionate ointment in the treatment of limited chronic plaque psoriasis

Background:

Chronic plaque psoriasis is a common papulosquamous skin disorder, for which a number of topical agents are being used including coal tar, topical steroids and more recently topical calcipotriol/betamethasone dipropionate. There is no study comparing purified coal tar preparation with calcipotriol/betamethasone dipropionate ointment in limited chronic plaque psoriasis.

Aims and Objectives:

A prospective randomized open label controlled trial to compare the efficacy and safety of topical application of coal tar-salicylic acid ointment with calcipotriol/betamethasone dipropionate ointment applied once at night for 12 weeks for the treatment of limited chronic plaque psoriasis.

Materials and Methods:

A total of 62 patients of limited chronic plaque psoriasis (body surface area <10%) were randomized into two treatment groups: Group A received topical application of 6% coal tar with 3% salicylic acid ointment and Group B received calcipotriol/betamethasone dipropionate, once at night for 12 weeks. Results were assessed based on psoriasis area severity index (PASI) scores and patient global assessment (PGA) at each visit.

Results:

Mean PASI was significantly lower at week 2 (P = 0.01) and week 4 follow-up (P = 0.05) and the mean reduction in PASI was significantly higher at week 2 (P = 0.02) with calcipotriol/betamethasone than coal tar-salicylic acid, but this difference was not sustained at subsequent follow-up visits. Similarly, PGA scores at weeks 2 and 4 were significantly lower with calcipotriol/betamethasone dipropionate ointment (P = 0.003 and P = 0.007 respectively). There was no significant difference in any parameter during subsequent follow-up visits or at the end of the treatment phase (12 weeks).

Conclusion:

Topical nightly application of calcipotriol/betamethasone dipropionate ointment leads to an initial, more rapid reduction in disease severity, but the overall outcome parameters are comparable in the two treatment groups.

Topical treatments for chronic plaque psoriasis

BACKGROUND

Chronic plaque psoriasis is the most common type of psoriasis, and it is characterised by redness, thickness, and scaling. First-line management of chronic plaque psoriasis is with topical treatments, including vitamin D analogues, topical corticosteroids, tar-based preparations, dithranol, salicylic acid, and topical retinoids.

OBJECTIVES

To compare the effectiveness, tolerability, and safety of topical treatments for chronic plaque psoriasis, relative to placebo, and to similarly compare vitamin D analogues (used alone or in combination) with other topical treatments.

SEARCH METHODS

We updated our searches of the following databases to February 2011: the Cochrane Skin Group Specialised Register, CENTRAL in The Cochrane Library (2011, Issue 2), MEDLINE (from 1948), EMBASE (from 1980), Science Citation Index (from 2008), Conference Proceedings Citation Index - Science (from 2008), BIOSIS (from 1993), Dissertation Abstracts via DialogClassic (all publication years), and Inside Conferences (all publication years).We identified ongoing and unpublished studies from the UK Clinical Research Network Study Portfolio and the metaRegister of Controlled Trials. We checked the bibliographies of published studies and reviews for further references to relevant trials, and we contacted trialists and companies for information about newly published studies.A separate search for adverse effects was undertaken in February 2011 using MEDLINE and EMBASE (from 2005).Final update searches for both RCTs and adverse effects were undertaken in August 2012. Although it has not been possible to incorporate RCTs and adverse effects studies identified through these final searches within this review, we will incorporate these into the next update.

SELECTION CRITERIA

Randomised trials comparing active topical treatments against placebo or against vitamin D analogues (used alone or in combination) in people with chronic plaque psoriasis.

DATA COLLECTION AND ANALYSIS

One author extracted study data and assessed study quality. A second author checked these data. We routinely contacted trialists and companies for missing data. We also extracted data on withdrawals and on local and systemic adverse events. We defined long-term trials as those with a duration of at least 24 weeks.

MAIN RESULTS

This update added 48 trials and provided evidence on 7 new active treatments. In total, the review included 177 randomised controlled trials, with 34,808 participants, including 26 trials of scalp psoriasis and 6 trials of inverse psoriasis, facial psoriasis, or both. The number of included studies counted by Review Manager (RevMan) is higher than these figures (190) because we entered each study reporting a placebo and an active comparison into the 'Characteristics of included studies' table as 2 studies.When used on the body, most vitamin D analogues were significantly more effective than placebo, with the standardised mean difference (SMD) ranging from -0.67 (95% CI -1.04 to -0.30; 1 study, 119 participants) for twice-daily becocalcidiol to SMD -1.66 (95% CI -2.66 to -0.67; 1 study, 11 participants) for once-daily paricalcitol. On a 6-point global improvement scale, these effects translate into 0.8 and 1.9 points, respectively. Most corticosteroids also performed better than placebo; potent corticosteroids (SMD -0.89; 95% CI -1.06 to -0.72; I² statistic = 65.1%; 14 studies, 2011 participants) had smaller benefits than very potent corticosteroids (SMD -1.56; 95% CI -1.87 to -1.26); I² statistic = 81.7%; 10 studies, 1264 participants). On a 6-point improvement scale, these benefits equate to 1.0 and 1.8 points, respectively. Dithranol, combined treatment with vitamin D/corticosteroid, and tazarotene all performed significantly better than placebo.Head-to-head comparisons of vitamin D for psoriasis of the body against potent or very potent corticosteroids had mixed findings. For both body and scalp psoriasis, combined treatment with vitamin D and corticosteroid performed significantly better than vitamin D alone or corticosteroid alone. Vitamin D generally performed better than coal tar, but findings relative to dithranol were mixed. When applied to psoriasis of the scalp, vitamin D was significantly less effective than both potent corticosteroids and very potent corticosteroids. Indirect evidence from placebo-controlled trials supported these findings.For both body and scalp psoriasis, potent corticosteroids were less likely than vitamin D to cause local adverse events, such as burning or irritation. Combined treatment with vitamin D/corticosteroid on either the body or the scalp was tolerated as well as potent corticosteroids, and significantly better than vitamin D alone. Only 25 trials assessed clinical cutaneous dermal atrophy; few cases were detected, but trials reported insufficient information to determine whether assessment methods were robust. Clinical measurements of dermal atrophy are insensitive and detect only the most severe cases. No comparison of topical agents found a significant difference in systemic adverse effects.

AUTHORS' CONCLUSIONS

Corticosteroids perform at least as well as vitamin D analogues, and they are associated with a lower incidence of local adverse events. However, for people with chronic plaque psoriasis receiving long-term treatment with corticosteroids, there remains a lack of evidence about the risk of skin dermal atrophy. Further research is required to inform long-term maintenance treatment and provide appropriate safety data.

Efficacy and tolerability of a cosmetically acceptable coal tar solution in the treatment of moderate plaque psoriasis: a controlled comparison with calcipotriene (calcipotriol) cream

BACKGROUND

Topical coal tar is a well known and effective treatment for psoriasis, but the messiness, staining, odor, and inconvenience associated with its use make patient satisfaction and compliance a challenge.

OBJECTIVE

To determine the efficacy, patient tolerability, and cosmetic acceptability of a new topical liquor carbonis distillate (LCD) 15% solution compared with calcipotriene (calcipotriol) cream in patients with moderate, chronic plaque psoriasis.

STUDY DESIGN

A randomized, single-blind, active-controlled, parallel-group, clinical trial consisting of a 12-week treatment phase and a 6-week post-treatment follow-up phase.

SETTING

Outpatient dermatology research unit in an academic hospital.

PATIENTS

Sixty adults with moderate, chronic plaque psoriasis (3-15% body surface area affected) not receiving other psoriasis therapies.

INTERVENTION

Patients were randomized to apply either an LCD 15% solution (Psorent) or a commercially available calcipotriene 0.005% cream (Dovonex) to their psoriasis areas (excluding the head) twice daily at home for 12 weeks.

ASSESSMENTS

A blinded investigator evaluated the patients' psoriasis using a modified Psoriasis Area and Severity Index (PASI) that excluded the head, and a Physician's Global Assessment (PGA) scale at weeks 0 (baseline), 2, 4, 8, and 12 (end of treatment), and 18 (6 weeks after treatment was withdrawn). Patients assessed their psoriasis symptoms and quality of life and completed a cosmetic acceptability survey about their medication.

OUTCOME MEASURES

The changes in the baseline PASI scores after 12 weeks of treatment were compared between LCD and calcipotriene groups. Additional comparisons were performed for success rates during treatment (PASI 75 and PASI 50), changes in PGA scores, patient-reported psoriasis symptom scores, patients' quality-of-life scores, and recurrence rates during post-treatment follow-up.

RESULTS

Both treatment groups showed improvement in psoriasis severity and quality of life. However, the LCD group had greater mean reductions in PASI scores: 58% vs 37% in the calcipotriene group (p < 0.05) at week 12. Additionally, the LCD group had more patients (14/27) with absent or minimal psoriasis on the PGA scale than the calcipotriene group (6/28) by the end of treatment (p < 0.05). LCD-treated patients also maintained their improvement better than calcipotriene-treated patients through week 18 after treatment was withdrawn for 6 weeks. Both treatments were well tolerated and cosmetically acceptable to patients.

CONCLUSION

The newly formulated LCD solution, applied twice daily at home for 12 weeks, was more effective and as well tolerated and cosmetically acceptable as the calcipotriene cream over 12 weeks of treatment and 6 weeks of follow-up. The LCD solution is a patient-accepted and effective corticosteroid-sparing treatment alternative for psoriasis patients.

Washability and fabric‐staining properties of a novel phospholipid‐structured coal tar formulation

BACKGROUND

Coal tar is one of the most preferred and frequently used medicinal agents in various dermatological diseases. However, the coal tar formulations available for clinical use suffer from the limitation of staining clothes and skin, eventually leading to a high degree of patient non-compliance.

OBJECTIVE

To test the staining property of a lecithinized formulation vis-a-vis a conventional formulation of coal tar employing different types of fabric.

METHODS

Six fabrics with different blends of cotton and polyester were employed to test the staining and washability of two coal tar formulations following application for 24 hours and 48 hours.

RESULTS

The study revealed the distinct superiority of the lecithinized coal tar formulation vis-a-vis the conventional marketed formulation due to its markedly reduced staining and easier washability. A significant reduction in the staining of fabrics containing polyester was observed with the lecithinized formulation, with the stain becoming progressively worse as the proportion of polyester in the fabric increased. The stains washed off completely with detergent in the case of the lecithinized coal tar formulation, whereas stains from the conventional coal tar formulation remained intact.

CONCLUSION

The developed lecithinized formulation, owing to its superior non-staining and washability characteristics, would potentially increase the acceptability of coal tar amongst patients.

Topical treatments for chronic plaque psoriasis

BACKGROUND

Chronic plaque psoriasis is the most common type of psoriasis and is characterised by redness, thickness and scaling. First line management of chronic plaque psoriasis is with topical treatments, including vitamin D analogues, topical corticosteroids, tar-based preparations, dithranol, salicylic acid and topical retinoids.

OBJECTIVES

To compare the effectiveness, tolerability and safety of topical treatments for chronic plaque psoriasis with placebo; to compare vitamin D analogues with other topical treatments.

SEARCH STRATEGY

The Cochrane Skin Group's Trials Register was searched (2004/12). To update an unpublished 2002 review we also searched CENTRAL in The Cochrane Library (Issue 1,2005); MEDLINE (to 2005/02); EMBASE (to 2005/08); Science Citation Index (to 2005); Biosis (to 2005); Dissertation Abstracts (all publication years); Inside Conferences (all publication years); SIGLE (to 2005); National Research Register (all projects with a start date of 2001 to 2005); metaRegister of Current Controlled Trials.

SELECTION CRITERIA

Randomised trials comparing treatments against placebo or against vitamin D analogues in people with chronic plaque psoriasis.

DATA COLLECTION AND ANALYSIS

One author extracted study data and assessed study quality. A second author checked these data. We routinely contacted triallists and companies for missing data. We extracted data on withdrawals and adverse events.

MAIN RESULTS

The review included 131 RCTs with 21,448 participants. Vitamin D was significantly more effective than placebo, although there was a wide variation in effect size with the standardised mean difference (SMD) ranging from -0.82 (95% CI -1.34 to -0.29) to -1.90 (95% CI -2.09 to -1.71). With one exception, all corticosteroids performed better than placebo, with potent corticosteroids (SMD: -0.95 (95% CI: -1.11 to -0.80; I(2): 61.1%; 17 studies; 2386 participants)) having smaller benefits than very potent corticosteroids (SMD: -1.29 (95% CI: -1.45 to -1.13; I(2): 53.2%; 11 studies; 1571 participants)). Dithranol and tazarotene performed better than placebo. Head-to-head comparisons of vitamin D against potent or very potent corticosteroids found no significant differences. However, combined treatment with vitamin D /corticosteroid performed significantly better than either vitamin D alone or corticosteroid alone. Vitamin D performed better than coal tar, but findings relative to dithranol were mixed. Potent corticosteroids were less likely than vitamin D to cause local adverse events. No comparison of topical agents found a significant difference in systemic adverse effects.

AUTHORS' CONCLUSIONS

Corticosteroids perform as well as vitamin D analogues and are associated with a lower incidence of local adverse events. Further research is required to inform long-term maintenance treatment.

Management of childhood psoriasis

Treating children with psoriasis represents one of the most rewarding yet constantly challenging endeavors in dermatology. These patients require time, energy, enthusiasm, empathy, and current, comprehensive knowledge of the unique clinical presentations in children and available therapies, including clinical action spectrum, mechanism of action, potential toxicity, and monitoring. Longitudinal trials examining the epidemiology and natural history of psoriasis, as well as the safety and efficacy of current and emerging treatments, are desperately needed in the pediatric population. Partner with the patient, family, and other multidisciplinary providers to form an educational and therapeutic alliance. Early in the course of disease, schedule frequent visits for reinforcement of the therapeutic plan, education, clinical and treatment monitoring, and support. As the disease and the patient's physical, psychosocial and emotional level of functioning evolve, so too will the requirement for follow-up and monitoring. Patient advocacy and education groups, such as the National Psoriasis Foundation (www.psoriasis.org; 800-723-9166) are excellent resources and can serve as an extension of your comprehensive care.

Topical tar: back to the future

The use of medicinal tar for dermatologic disorders dates back to the ancient times. Although coal tar is utilized more frequently in modern dermatology, wood tars have also been widely employed. Tar is used mainly in the treatment of chronic stable plaque psoriasis, scalp psoriasis, atopic dermatitis, and seborrheic dermatitis, either alone or in combination therapy with other medications, phototherapy, or both. Many modifications have been made to tar preparations to increase their acceptability, as some dislike its odor, messy application, and staining of clothing. One should consider a tried and true treatment with tar that has led to clearing of lesions and prolonged remission times. Occupational studies have demonstrated the carcinogenicity of tar; however, epidemiologic studies do not confirm similar outcomes when used topically. This article will review the pharmacology, formulations, efficacy, and adverse effects of crude coal tar and other tars in the treatment of selected dermatologic conditions.

Serum levels of the pro-inflammatory cytokine interleukin-12 and the anti-inflammatory cytokine interleukin-10 in patients with psoriasis treated by the Goeckerman regimen

BACKGROUND

The Goeckerman regimen (GR) involves the dermal application of a crude coal tar (polycyclic aromatic hydrocarbon, PAH) and exposure to ultraviolet (UV) radiation. Both PAH and UV radiation exhibit immunosuppressive activity. This study describes the changes in the serum levels of the pro-inflammatory cytokine interleukin-12 (IL-12) and the anti-inflammatory cytokine IL-10 in patients with psoriasis (n = 55) treated with GR.

METHODS

The serum levels of IL-12 and IL-10 were compared before and after GR. In addition, the IL-12 and IL-10 levels in psoriatic patients were compared with those in a control group of healthy blood donors (n = 47). The Psoriasis Area and Severity Index (PASI) was used to evaluate the efficacy of GR.

RESULTS

When compared with the control group, both IL-12 and IL-10 were significantly higher in psoriatic patients in all cases (P < 0.001). When compared before and after GR, the IL-12 and IL-10 levels (P < 0.01) and PASI value (P < 0.001) were significantly lower after GR. The decrease in the serum level of IL-12 and IL-10 after GR was related to the entry value before GR (IL-12, r = 0.60, P < 0.001; IL-10, r = 0.36, P < 0.01). There was a significant correlation between the IL-10 level before GR and the PASI value after GR (r = -0.39; P < 0.01).

CONCLUSIONS

The results indicate a strong pro-inflammatory effect of IL-12 in the immunopathogenesis of psoriasis, and confirm the immunosuppressive and anti-inflammatory effect of GR. IL-10 seems to be a promising individual marker for a positive effect of GR therapy.

Melanocyte receptors: clinical implications and therapeutic relevance

The activation or the inhibition of melanocyte-specific receptors offers novel means of augmenting normal melanocyte function, skin color, and photoprotection, or treating melanocytic disorders, namely at this time, metastatic melanoma. Melanocyte-specific receptors include melanocortin-1 (MCR1) and melatonin receptors. Other receptors that play an important role in melanoma progression are G-protein couple receptors such as Frizzled 5 and receptor tyrosine kinases such as c-Kit and hepatocyte growth factor (HGF) receptor. These receptors activate two crucial cell-signaling pathways, RAS/RAF/MEK/ERK and PI3K/AKT, integral to melanoma cell survival, and can serve as targets for therapy of disseminated melanoma. Activation of death receptors is another pathway that can be exploited with targeted therapeutics to control advanced melanoma. This article reviews the current understanding of melanocyte receptors, their agonists and inhibitors, and their potential to treat the melanocytic pathology.

Psoriasis: consensus on topical therapies

OBJECTIVE

A consensus conference was convened to evaluate the topical treatment of psoriasis.

PARTICIPANTS

Members of the International Psoriasis Council (IPC) with broad clinical experience in the treatment of psoriasis and a specialist in meta- and pharmacoeconomic analyses were invited to participate on the consensus panel. Those accepting the invitation convened in Saariselkä, Finland.

EVIDENCE

An advisory group on topical treatments was nominated by the organizing panel members. All participants reported at the consensus conference on evidence based data with respect to disease severity assessment, the available data on efficacy and safety and on a comparative efficacy/safety analysis.

CONSENSUS PROCESS

At the consensus conference, the presentations were discussed and conclusions, which were reached by the group, were recorded. Active participants of the group wrote assigned sections of this consensus document with a majority of participants agreed on the conclusions.

Evidence of covalent interaction of fumaric acid esters with sulfhydryl groups in peptides

Fumaric acid esters, namely dimethylfumarate, have been used for the treatment of psoriasis for many years. Still, their mode of action is not fully clear. Because addition of nucleophiles to the double bonds of fumarates can occur (Michael analogous addition), a study of the interaction of fumarates with cysteine and cysteine-containing peptides possessing nucleophilic sulfhydryl group was carried out. Experiments were performed in aqueous medium at pH 7.4 and at 37 degrees C to simulate physiological conditions. It was proven by mass spectrometric measurements using an ion-trap and time-of-flight instrument that a covalent bond can form between fumarates and the sulfhydryl group of cysteine or cysteinyl residues in peptides. Structures of the interaction products were elucidated by multistage mass spectrometry applying collision-induced dissociation. Higher reactivity of dimethylfumarate in comparison to monomethylfumarate and fumaric acid was observed.