An analysis of IL-36 signature genes and individuals with IL1RL2 knockout mutations validates IL-36 as a psoriasis therapeutic target

Interleukin (IL)-36α, IL-36β, and IL-36γ are innate mediators of acute epithelial inflammation. We sought to demonstrate that these cytokines are also required for the pathogenesis of plaque psoriasis, a common and chronic skin disorder, caused by abnormal T helper 17 (T_H17) cell activation. To investigate this possibility, we first defined the genes that are induced by IL-36 cytokines in primary human keratinocytes. This enabled us to demonstrate a significant IL-36 signature among the transcripts that are up-regulated in plaque psoriasis and the susceptibility loci associated with the disease in genome-wide studies. Next, we investigated the impact of in vivo and ex vivo IL-36 receptor blockade using a neutralizing antibody or a recombinant antagonist. Both inhibitors had marked anti-inflammatory effects on psoriatic skin, demonstrated by statistically significant reductions in IL-17 expression, keratinocyte activation, and leukocyte infiltration. Finally, we explored the potential safety profile associated with IL-36 blockade by phenotyping 12 individuals carrying knockout mutations of the IL-36 receptor gene. We found that normal immune function was broadly preserved in these individuals, suggesting that IL-36 signaling inhibition would not substantially compromise host defenses. These observations, which integrate the results of transcriptomics and model system analysis, pave the way for early-stage clinical trials of IL-36 antagonists.

Fabrication of microstructured binary polymer brush "corrals" with integral pH sensing for studies of proton transport in model membrane systems

Binary brush structures consisting of poly(cysteine methacrylate) (PCysMA) "corrals" enclosed within poly(oligoethylene glycol methyl ether methacrylate) (POEGMA) "walls" are fabricated simply and efficiently using a two-step photochemical process. First, the C-Cl bonds of 4-(chloromethyl)phenylsilane monolayers are selectively converted into carboxylic acid groups by patterned exposure to UV light through a mask and POEGMA is grown from unmodified chlorinated regions by surface-initiated atom-transfer radical polymerisation (ATRP). Incorporation of a ratiometric fluorescent pH indicator, Nile Blue 2-(methacryloyloxy)ethyl carbamate (NBC), into the polymer brushes facilitates assessment of local changes in pH using a confocal laser scanning microscope with spectral resolution capability. Moreover, the dye label acts as a radical spin trap, enabling removal of halogen end-groups from the brushes via in situ dye addition during the polymerisation process. Second, an initiator is attached to the carboxylic acid-functionalised regions formed by UV photolysis in the patterning step, enabling growth of PCysMA brushes by ATRP. Transfer of the system to THF, a poor solvent for PCysMA, causes collapse of the PCysMA brushes. At the interface between the collapsed brush and solvent, selective derivatisation of amine groups is achieved by reaction with excess glutaraldehyde, facilitating attachment of aminobutyl(nitrile triacetic acid) (NTA). The PCysMA brush collapse is reversed on transfer to water, leaving it fully expanded but only functionalized at the brush-water interface. Following complexation of NTA with Ni2+, attachment of histidine-tagged proteorhodopsin and lipid deposition, light-activated transport of protons into the brush structure is demonstrated by measuring the ratiometric response of NBC in the POEGMA walls.

Exposure to biological therapies during conception and pregnancy: a systematic review

BACKGROUND

Biological therapies are effective treatments for psoriasis and are often prescribed to women of child-bearing age.

OBJECTIVES

To evaluate the safety of biological therapy in conception and/or pregnancy.

METHODS

We performed a systematic review of PubMed, MEDLINE, Embase and Cochrane databases for multivariate-adjusted studies of women exposed to biologics relevant to the treatment of psoriasis during conception and/or pregnancy.

RESULTS

We identified four population-based cohort studies involving 1300 women exposed to tumour necrosis factor (TNF)-α inhibitors (TNFi) 3 months prior to or during the first 3 months of pregnancy. These studies showed a trend towards drug-specific harm with TNFi exposure in women with different inflammatory diseases, with an increased risk of congenital malformations [three studies; odds ratio (OR) range 1·32-1·64] and preterm birth (one study; OR 1·69, 95% confidence interval 1·10-2·60). This trend did not reach statistical significance in all studies; study heterogeneity, variation across comparator cohorts, inadequate adjustment for important confounding variables such as co-therapy, and an absence of a common constellation of malformations means there is uncertainty about the causal role of TNFi. No studies specifically addressed the effect of TNFi exposure in psoriasis during conception and/or pregnancy, or of interleukin (IL)-17 and IL-12/23 antagonists in any indication.

CONCLUSIONS

When counselling women these findings must be balanced against the potential impact of untreated severe psoriasis on conception and/or pregnancy and maternal wellbeing; ongoing pharmacovigilance via registries remains essential to address this evidence gap.

Differential Drug Survival of Second-Line Biologic Therapies in Patients with Psoriasis: Observational Cohort Study from the British Association of Dermatologists Biologic Interventions Register (BADBIR)

Little is known about the drug survival of second-line biologic therapies for psoriasis in routine clinical practice. We assessed drug survival of second-line biologic therapies and estimated the risk of recurrent discontinuation due to adverse events or ineffectiveness in patients with psoriasis who had failed a first biologic therapy and switched to a second in a large, multicenter pharmacovigilance registry (n = 1,239; adalimumab, n = 538; etanercept, n = 104; ustekinumab, n = 597). The overall drug survival rate in the first year after switching was 77% (95% confidence interval = 74–79%), falling to 58% (55–61%) in the third year. Female sex, multiple comorbidities, concomitant therapy with cyclosporine, and a high Psoriasis Area and Severity Index at switching to the second-line biologic therapy were predictors of overall discontinuation (multivariable Cox proportional hazard model). Compared to adalimumab, patients receiving etanercept were more likely to discontinue therapy (hazard ratio = 1.87, 95% confidence interval = 1.24–2.83), whereas patients receiving ustekinumab were more likely to persist (hazard ratio = 0.46; 95% confidence interval = 0.33–0.64). Discontinuation of the first biologic therapy because of adverse events was associated with an increased rate of second drug discontinuation because of adverse events (hazard ratio = 2.55; 95% confidence interval = 1.50–4.32). In conclusion, drug survival rates differed among biologic therapies and decreased over time; second-line discontinuation because of adverse events was more common among those who discontinued first-line treatment for this reason. The results of this study should support clinical decision making when choosing second-line biologic therapy for patients with psoriasis.

Risk of uveitis and inflammatory bowel disease in people with psoriatic arthritis: a population-based cohort study

OBJECTIVES

To determine the risk of uveitis and inflammatory bowel disease (IBD) in patients with psoriatic arthritis (PsA) compared with the general population and patients with psoriasis.

METHODS

A cohort study using data from the UK Clinical Practice Research Datalink between 1998 and 2014. Patients with incident PsA aged 18-89 years were identified and matched to a cohort of patients with psoriasis and a general population cohort. The incidence of uveitis, all IBD, Crohn's disease and ulcerative colitis was calculated for each study cohort and adjusted relative risks (RR_adj) were calculated using conditional Poisson regression.

RESULTS

6783 incident cases of PsA were identified with a median age of 49 years. The risk of uveitis was significantly higher in the PsA cohort than in the general population and psoriasis cohorts (RR_adj 3.55, 95% CI 2.21 to 5.70 and RR_adj 2.13, 95% CI 1.40 to 3.24, respectively). A significant increase was observed for Crohn's disease (RR_adj 2.96, 95% CI 1.46 to 6.00 and RR_adj3.60, 95% CI 1.83 to 7.10) but not for ulcerative colitis (RR_adj1.30, 95% CI 0.66 to 2.56 and RR_adj0.98, 95% CI 0.50 to 1.92).

CONCLUSIONS

In a primary care-based incidence cohort of patients with PsA, there were substantial risks of developing uveitis and/or Crohn's disease, but not ulcerative colitis, when compared with the general population and psoriasis controls.

Exome-wide association study reveals novel psoriasis susceptibility locus at TNFSF15 and rare protective alleles in genes contributing to type I IFN signalling

Psoriasis is a common inflammatory skin disorder for which multiple genetic susceptibility loci have been identified, but few resolved to specific functional variants. In this study, we sought to identify common and rare psoriasis-associated gene-centric variation. Using exome arrays we genotyped four independent cohorts, totalling 11 861 psoriasis cases and 28 610 controls, aggregating the dataset through statistical meta-analysis. Single variant analysis detected a previously unreported risk locus at TNFSF15 (rs6478108; P = 1.50 × 10-8, OR = 1.10), and association of common protein-altering variants at 11 loci previously implicated in psoriasis susceptibility. We validate previous reports of protective low-frequency protein-altering variants within IFIH1 (encoding an innate antiviral receptor) and TYK2 (encoding a Janus kinase), in each case establishing a further series of protective rare variants (minor allele frequency < 0.01) via gene-wide aggregation testing (IFIH1: pburden = 2.53 × 10-7, OR = 0.707; TYK2: pburden = 6.17 × 10-4, OR = 0.744). Both genes play significant roles in type I interferon (IFN) production and signalling. Several of the protective rare and low-frequency variants in IFIH1 and TYK2 disrupt conserved protein domains, highlighting potential mechanisms through which their effect may be exerted.

Comparative effectiveness of biological therapies on improvements in quality of life in patients with psoriasis

Background

Evidence of the comparative effectiveness of biological therapies for psoriasis on health‐related quality of life (HRQoL) in routine clinical practice is limited.

Objectives

To examine the comparative effectiveness of adalimumab, etanercept and ustekinumab on HRQoL in patients with psoriasis, and to identify potential predictors for improved HRQoL.

Methods

This was a prospective cohort study in which changes in HRQoL were assessed using the Dermatology Life Quality Index (DLQI) and EuroQoL‐5D (EQ‐5D) at 6 and 12 months. Multivariable regression models were developed to identify factors associated with achieving a DLQI of 0/1 and improvements in the EQ‐5D utility score.

Results

In total, 2152 patients with psoriasis were included, with 1239 patients on adalimumab, 517 on etanercept and 396 on ustekinumab; 81% were biologic naïve. For the entire cohort, the median (interquartile range) DLQI and EQ‐5D improved from 18 (13–24) and 0·73 (0·69–0·80) at baseline to 2 (0–7) and 0·85 (0·69–1·00) at 6 months, respectively (P < 0·001). Similar improvements were achieved at 12 months. At 12 months, multivariable regression modelling showed that female sex, multiple comorbidities, smoking and a higher DLQI or a lower EQ‐5D utility score at baseline predicted a lower likelihood of achieving a DLQI of 0/1 or improvement in the EQ‐5D. Compared with adalimumab, patients receiving etanercept, but not ustekinumab, were less likely to achieve a DLQI of 0/1. There was no significant difference between the biological therapies in EQ‐5D improvement.

Conclusions

In routine clinical practice biological therapies produce marked improvement in HRQoL, which is influenced by the choice of biological therapy, baseline impairment in HRQoL, lifestyle characteristics and comorbidities. These findings should help inform selection of optimal biological therapy for patients related to improvements in HRQoL.

What's already known about this topic?

Evidence of the comparative effectiveness of biological therapies for psoriasis on health‐related quality of life (HRQoL) in routine clinical practice is limited.

Earlier observational studies were either cross‐sectional, thereby limiting the ability to compare changes in HRQoL, or cohort studies that have not taken into account important clinical factors that could influence treatment response, such as alterations in dosing regimens of biological therapies and the concomitant use of conventional systemic treatments for psoriasis.

What does this study add?

This large prospective cohort study found that in routine clinical practice, the use of biological therapies for psoriasis was associated with marked improvements in HRQoL over 12 months.

These improvements were influenced by the choice of biological therapy, baseline impairment in HRQoL, lifestyle characteristics and comorbidities.

Compared with adalimumab, patients receiving etanercept were less likely to achieve a DLQI of 0/1, but there was no significant difference between ustekinumab and adalimumab in the proportion of patients achieving a DLQI of 0/1.

There was no significant difference between the three biological therapies in level of improvement in the EQ‐5D.

Linked Comment: Finlay. Br J Dermatol 2017; 177:1164–1165.

Risk of Serious Infection in Patients with Psoriasis Receiving Biologic Therapies: A Prospective Cohort Study from the British Association of Dermatologists Biologic Interventions Register (BADBIR)

Serious infection is a concern for patients with psoriasis receiving biologic therapies. We assessed the risk of serious infections for biologics used to treat psoriasis by comparison with a cohort receiving non-biologic systemic therapies in a propensity score-weighted Cox proportional hazards model using data from the British Association of Dermatologists Biologic Interventions Register. Overall, 1,352; 3,271; and 994 participants were included in the etanercept, adalimumab, ustekinumab cohorts, respectively, and 3,421 participants were in the non-biologic cohort. A total of 283 patients had a serious infection; the incidence rates with 95% confidence intervals (CI) per 1,000 person-years were as follows: non-biologic, 14.2 (11.5-17.4); etanercept, 15.3 (11.6-20.1); adalimumab, 13.9 (11.4-16.6); and ustekinumab, 15.1 (10.8-21.1). No significant increases in the risk of serious infection were observed for etanercept (hazard ratio [HR] = 1.10, 95% CI = 0.75-1.60), adalimumab (HR = 0.93, 95% CI = 0.69-1.26), or ustekinumab (HR = 0.92, 95% CI = 0.60-1.41) compared with non-biologic systemic therapies or methotrexate-only (etanercept: HR = 1.47, 95% CI = 0.95-2.28; adalimumab: HR = 1.26, 95% CI = 0.86-1.84; ustekinumab: HR = 1.22, 95% CI = 0.75-1.99). The risk of serious infection should not be a key discriminator for patients and clinicians when choosing between non-biologic systemic therapies, etanercept, adalimumab, and ustekinumab for the treatment of psoriasis.

Cross-phenotype association mapping of the MHC identifies genetic variants that differentiate psoriatic arthritis from psoriasis

Objectives

Psoriatic arthritis (PsA) is a chronic inflammatory arthritis, with a strong heritable component, affecting patients with psoriasis. Here we attempt to identify genetic variants within the major histocompatibility complex (MHC) that differentiate patients with PsA from patients with cutaneous psoriasis alone (PsC).

Methods

2808 patients with PsC, 1945 patients with PsA and 8920 population controls were genotyped. We imputed SNPs, amino acids and classical HLA alleles across the MHC and tested for association with PsA compared to population controls and the PsC patient group. In addition we investigated the impact of the age of disease onset on associations.

Results

HLA-C*06:02 was protective of PsA compared to PsC (p=9.57×10⁻⁶⁶, OR 0.37). The HLA-C*06:02 risk allele was associated with a younger age of psoriasis onset in all patients (p=1.01×10⁻⁵⁹). After controlling for the age of psoriasis onset no association of PsA to HLA-C*06:02 (p=0.07) was observed; instead, the most significant association was to amino acid at position 97 of HLA-B (p=1.54×10⁻⁹) where the presence of asparagine or serine residue increased PsA risk. Asparagine at position 97 of HLA-B defines the HLA-B*27 alleles.

Conclusions

By controlling for the age of psoriasis onset, we show, for the first time, that HLA-C*06:02 is not associated with PsA and that amino acid position 97 of HLA-B differentiates PsA from PsC. This amino acid also represents the largest genetic effect for ankylosing spondylitis, thereby refining the genetic overlap of these two spondyloarthropathies. Correcting for bias has important implications for cross-phenotype genetic studies.

Obesity, Waist Circumference, Weight Change, and Risk of Incident Psoriasis: Prospective Data from the HUNT Study

Although psoriasis has been associated with obesity, there are few prospective studies with objective measures. We prospectively examined the effect of body mass index, waist circumference, waist-hip ratio, and 10-year weight change on the risk of developing psoriasis among 33,734 people in the population-based Nord-Trøndelag Health Study (i.e., HUNT), Norway. During follow-up, 369 incident psoriasis cases occurred. Relative risk (RR) of psoriasis was estimated by Cox regression. One standard deviation higher body mass index, waist circumference, and waist-hip ratio gave RRs of 1.22 (95% confidence interval [CI] = 1.11-1.34), 1.26 (95% CI = 1.15-1.39), and 1.18 (95% CI = 1.07-1.31), respectively. Compared with normal weight participants, obese people had an RR of 1.87 (95% CI = 1.38-2.52), whereas comparing the fourth with the first quartile of waist circumference gave an RR of 1.95 (95% CI = 1.46-2.61). One standard deviation higher weight change gave an RR of 1.20 (95% CI = 1.07-1.35), and people who increased their body weight by 10 kg or more had an RR of 1.72 (95% CI = 1.15-2.58) compared with being weight stable. In conclusion, obesity and high abdominal fat mass doubles the risk of psoriasis, and long-term weight gain substantially increases psoriasis risk. Preventing weight gain and promoting maintenance of a normal body weight could reduce incidence of psoriasis.

Patterns of biologic therapy use in the management of psoriasis: cohort study from the British Association of Dermatologists Biologic Interventions Register (BADBIR)

BACKGROUND

Treatment modifications, including dose escalations, dose reductions, switches, discontinuations and restarts of biologics may be necessary in the management of psoriasis but the patterns of usage are incompletely defined.

OBJECTIVES

To examine the treatment utilization patterns of adalimumab, etanercept and ustekinumab among biologic-naïve and non-naïve patients with psoriasis enrolled in the British Association of Dermatologists Biologic Interventions Register (BADBIR).

METHODS

The study cohort included adults with chronic plaque psoriasis who were followed up for ≥ 12 months. Treatment modifications were assessed during the first year of therapy. The time-trend method, comparing the cumulative dose (CD) patients received with the recommended cumulative dose (RCD), was used to assess dosing patterns. Concomitant use of other systemic treatments was also examined.

RESULTS

In total, 2980 patients (adalimumab: 1675; etanercept: 996; ustekinumab: 309) were included; 79·2% were biologic-naïve. Over 12 months, 77·4% of patients continued the biologic, 2·6% restarted therapy after a break of ≥ 90 days, 2·5% discontinued, and 17·5% switched biologic therapy. Most patients (85·7%) received the RCD of the biologic, although 8·1% were exposed to a higher CD. In total, 749 (25·1%) patients used conventional systemic therapies concomitantly with a biologic at some stage; methotrexate was used most commonly (458; 61·2%). Of those using combination therapy, 454 (60·6%) continued the use of the conventional systemic therapy for > 120 days after the start of the biologic.

CONCLUSIONS

More than one-third of patients experienced treatment modifications within the first year of initiating a biologic. Conventional systemic therapies, particularly methotrexate, were commonly used concurrently, which should be considered when evaluating treatment response and adverse events to biologics in real-world observational studies.

Screening for anxiety and depression in people with psoriasis: a cross-sectional study in a tertiary referral setting

BACKGROUND

National Institute for Health and Care Excellence guidance recommends assessment of psychological and social well-being in people with psoriasis.

OBJECTIVES

To screen systematically for depression and anxiety in patients with psoriasis in routine clinical practice and to identify at-risk groups for psychiatric morbidity.

METHODS

Consecutive patients attending a single, tertiary centre over a 10-month period were invited to complete the Patient Health Questionnaire Depression Scale (PHQ-9), Generalized Anxiety Disorder Scale (GAD-7) and Dermatology Life Quality Index (DLQI) as part of IMPARTS: Integrating Mental and Physical Healthcare: Research, Training and Services. Information on demographics, treatment and clinical disease severity was collated from electronic patient records. Regression models were used to identify at-risk groups for psychiatric morbidity.

RESULTS

Of 607 patients included (56·2% on biologics), 9·9% (95% confidence interval 7·5-12·3%) screened positive for major depressive disorder (MDD) and 13·1% (79/604) (95% confidence interval 10·4-15·8%) for generalized anxiety disorder (GAD; GAD-7 score > 9). Suicidal ideation was reported in 35% of those with MDD; DLQI was < 10 in 38·3% and 45·6% cases of MDD and GAD, respectively. After adjusting for covariates, the risk of MDD or GAD was significantly higher in women and those with severe clinical disease, psoriatic arthritis and previous depression/anxiety. The risk of GAD was significantly increased with Asian ethnicity and use of topical treatments only.

CONCLUSIONS

Systematic screening for anxiety and depression identifies clinically important levels of depression and anxiety that may be missed using DLQI data alone. Women and those with severe disease, psoriatic arthritis and/or a prior history of psychiatric morbidity may be at particular risk.

Treatment of severe, chronic hand eczema: results from a UK-wide survey

Treatment of severe hand eczema (HE) that is resistant to topical potent corticosteroid treatment is challenging. In 2013, we surveyed 194 UK dermatologists to obtain information about their usual treatment pathways to inform the choice of the comparator in a trial of alitretinoin in severe HE (ALPHA trial); the results indicated that the treatment approaches favoured by UK dermatologists differ. Psoralen combined with ultraviolet A (PUVA) and alitretinoin were identified as the most frequent first-line treatment options for hyperkeratotic HE, whereas oral corticosteroids were identified as the most frequent first-line treatment for vesicular HE, followed by PUVA and alitretinoin. In terms of potential adverse effects of long-term or repeated use, oral steroids and ciclosporin A were reported to cause most concern. There is uncertainty about which treatment gives the best short and long-term outcomes, because of a lack of definitive randomised controlled trials evaluating the effectiveness of different treatment pathways in severe HE.

AP1S3 Mutations Cause Skin Autoinflammation by Disrupting Keratinocyte Autophagy and Up-Regulating IL-36 Production

Prominent skin involvement is a defining characteristic of autoinflammatory disorders caused by abnormal IL-1 signaling. However, the pathways and cell types that drive cutaneous autoinflammatory features remain poorly understood. We sought to address this issue by investigating the pathogenesis of pustular psoriasis, a model of autoinflammatory disorders with predominant cutaneous manifestations. We specifically characterized the impact of mutations affecting AP1S3, a disease gene previously identified by our group and validated here in a newly ascertained patient resource. We first showed that AP1S3 expression is distinctively elevated in keratinocytes. Because AP1S3 encodes a protein implicated in autophagosome formation, we next investigated the effects of gene silencing on this pathway. We found that AP1S3 knockout disrupts keratinocyte autophagy, causing abnormal accumulation of p62, an adaptor protein mediating NF-κB activation. We showed that as a consequence, AP1S3-deficient cells up-regulate IL-1 signaling and overexpress IL-36α, a cytokine that is emerging as an important mediator of skin inflammation. These abnormal immune profiles were recapitulated by pharmacological inhibition of autophagy and verified in patient keratinocytes, where they were reversed by IL-36 blockade. These findings show that keratinocytes play a key role in skin autoinflammation and identify autophagy modulation of IL-36 signaling as a therapeutic target.

Speech and swallowing dysfunction in multisystem atrophy

Speech and swallowing functioning was assessed in 10 patients diagnosed as having the degenerative disease multisystem atrophy (MSA). Swallowing was assessed using clinical and radiographic examinations. The results showed that three of the 10 subjects were aspirating. The aspiration was silent and therefore not evident on clinical swallowing assessment, although there were indications of laryngeal dysfunction. The remaining subjects all had some degree of swallowing dysfunction and presented with at least a mild dysarthria. This suggests that any MSA patient presenting with even mild dysarthria should have a detailed swallowing assessment. The role of the speech therapist in the multidisciplinary management of patients with MSA is discussed.

Risk of Serious Infections in Patients with Psoriasis on Biologic Therapies: A Systematic Review and Meta-Analysis

A comprehensive evaluation of the risk of serious infections in biologic therapies for psoriasis is lacking. We performed a systematic review and meta-analysis of randomized controlled trials (RCTs) and prospective cohort studies reporting serious infections in people taking any licensed biologic therapy for psoriasis compared with those taking placebo, nonbiologic therapy, or other biologic therapies. The quality of the studies was assessed using Grading of Recommendations Assessment, Development and Evaluation criteria. No significant heterogeneity was detected in data from 32 RCTs (n = 13,359 participants) and one cohort study (n = 4,993 participants). In adults, low- to very-low-quality RCT data showed no significant difference between any biologic therapy and placebo at weeks 12–16 (overall pooled Peto odds ratio = 0.71, 95% confidence interval = 0.36–1.41) and weeks 20–30 (odds ratio = 2.27, 95% confidence interval = 0.45–11.49). No significant differences were found in any of the other comparisons in underpowered RCT data. Prospective cohort study data of low quality suggests that only adalimumab (adjusted hazard ratio [adjHR] = 2.52, 95% confidence interval = 1.47–4.32) was associated with a significantly higher risk of serious infection compared with retinoid and/or phototherapy in adults. No association between biologic therapies and serious infections in patients with psoriasis who were eligible for RCTs was detected. Further observational studies are needed to inform the uncertainty around this risk in the real world.

Differential Drug Survival of Biologic Therapies for the Treatment of Psoriasis: A Prospective Observational Cohort Study from the British Association of Dermatologists Biologic Interventions Register (BADBIR)

Drug survival reflects a drug's effectiveness, safety, and tolerability. We assessed the drug survival of biologics used to treat psoriasis in a prospective national pharmacovigilance cohort (British Association of Dermatologists Biologic Interventions Register (BADBIR)). The survival rates of the first course of biologics for 3,523 biologic-naive patients with chronic plaque psoriasis were compared using survival analysis techniques and predictors of discontinuation analyzed using a multivariate Cox proportional hazards model. Data for patients on adalimumab (n=1,879), etanercept (n=1,098), infliximab (n=96), and ustekinumab (n=450) were available. The overall survival rate in the first year was 77%, falling to 53% in the third year. Multivariate analysis showed that female gender (hazard ratio (HR) 1.22; 95% confidence interval (CI): 1.09-1.37), being a current smoker (HR 1.19; 95% CI: 1.03-1.38), and a higher baseline dermatology life quality index (HR 1.01; 95% CI: 1.00-1.02) were predictors of discontinuation. Presence of psoriatic arthritis (HR 0.82; 95% CI: 0.71-0.96) was a predictor for drug survival. As compared with adalimumab, patients on etanercept (HR 1.63; 95% CI: 1.45-1.84) or infliximab (HR 1.56; 95% CI: 1.16-2.09) were more likely to discontinue therapy, whereas patients on ustekinumab were more likely to persist (HR 0.48; 95% CI: 0.37-0.62). After accounting for relevant covariates, ustekinumab had the highest first-course drug survival. The results of this study will aid clinical decision making when choosing biologic therapy for psoriasis patients.

Biological therapies for the treatment of severe psoriasis in patients with previous exposure to biological therapy: a cost-effectiveness analysis

BACKGROUND

Biologic therapies have revolutionised the care of patients with psoriasis, although they come at significant extra cost. Guidance on their use in the UK National Health Service (NHS) has so far focused on patients who are "biologic naive", yet a minority of patients have poor response and require further treatment.

OBJECTIVES

To assess the potential cost effectiveness of sequential biologic therapies in patients with psoriasis who have been exposed to previous biologic therapy.

METHODS

A two-part model with a 10-year time horizon was built to model an initial 13.5-week "trial" phase and a longer-term "treatment" period with annual Markov cycles. Psoriasis Area and Severity Index (PASI) response rates from subgroup analyses of three randomised placebo-controlled trials evaluating biologic agents were considered. A meta-analysis of these data provided probabilities of achieving PASI response (50/75/90) in the short term, and published evidence and assumptions were used to predict outcomes over the longer term. Benefits were measured in quality-adjusted life years (QALYs), and costs (2013-14) to the UK NHS included drugs, administration, monitoring, and hospitalisation. Costs and benefits were discounted 3.5 % per annum. Cost effectiveness of sequential biologic therapy was measured using an incremental cost-effectiveness ratio (ICER) compared to best supportive care (BSC). Extensive sensitivity analyses were performed to assess the impact of alternative assumptions on the results.

RESULTS

Results indicate that over 10 years, switching to a second biologic following intolerance to or failure of a first is likely to generate more QALYs than BSC, but at a higher cost. Base case results suggest the ICER of the second biologic compared to BSC is £17,681 per QALY; however, sensitivity analyses indicate that changes in the efficacy of BSC, drug costs, dropout rates, and rates of hospitalisation have a significant impact, causing the ICER to range from less than £10,000 to over £50,000 per QALY.

CONCLUSIONS

Further biologic therapy for patients with psoriasis who have previously been treated with biologic therapy may be cost effective, although there is considerable uncertainty in the results. Future studies should be designed to evaluate the clinical efficacy of biologic therapies in this subgroup with particular attention given to short-term and longer-term responses.

Characterization of innate lymphoid cells in human skin and blood demonstrates increase of NKp44+ ILC3 in psoriasis

Innate lymphoid cells (ILCs) are increasingly appreciated as key regulators of tissue immunity. However, their role in human tissue homeostasis and disease remains to be fully elucidated. Here we characterize the ILCs in human skin from healthy individuals and from the inflammatory skin disease psoriasis. We show that a substantial proportion of IL-17A and IL-22 producing cells in the skin and blood of normal individuals and psoriasis patients are CD3-negative innate lymphocytes. Deep immunophenotyping of human ILC subsets showed a statistically significant increase in the frequency of circulating NKp44+ ILC3 in the blood of psoriasis patients compared with healthy individuals or atopic dermatitis patients. More than 50% of circulating NKp44+ ILC3 expressed cutaneous lymphocyte-associated antigen, indicating their potential for skin homing. Analysis of skin tissue revealed a significantly increased frequency of total ILCs in the skin compared with blood. Moreover, the frequency of NKp44+ ILC3 was significantly increased in non-lesional psoriatic skin compared with normal skin. A detailed time course of a psoriasis patient treated with anti-tumor necrosis factor showed a close association between therapeutic response, decrease in inflammatory skin lesions, and decrease of circulating NKp44+ ILC3. Overall, data from this initial observational study suggest a potential role for NKp44+ ILC3 in psoriasis pathogenesis.

Psoriasis: guidance on assessment and referral

This concise guideline summarises the key recommendations from the recent National Institute for Health and Care Excellence (NICE) clinical guideline on the assessment and management of psoriasis (CG153) that are relevant to the non-dermatologist. The aim is to highlight important considerations for assessment and referral of people with psoriasis, including identification of relevant comorbid conditions. Psoriasis is a common inflammatory skin condition and, especially when severe, can be associated with increased risk of cardiovascular disease, diabetes and depression. Functional, psychological and social morbidity can also be encountered, and the extent of the disability is frequently underestimated. Importantly, highly effective treatments are available. Appropriate assessment and referral of people with psoriasis therefore has the potential to improve outcomes by correctly identifying the appropriate treatment pathway. Assessment should involve not only disease severity but also the impact on patient well-being and whether the patient has any comorbid conditions, such as psoriatic arthritis, which requires rapid referral to a rheumatologist.

Predicting treatment response in psoriasis using serum levels of adalimumab and etanercept: a single-centre, cohort study

BACKGROUND

A substantial proportion of patients with psoriasis do not respond, or lose initial response to tumour necrosis factor-α antagonists. One possible mechanism relates to subtherapeutic drug levels due to an immunogenic antibody response.

OBJECTIVES

To investigate the association between serum adalimumab and etanercept levels, antidrug antibody levels and clinical response in a cohort of patients with psoriasis using a commercially available enzyme-linked immunoassay.

METHODS

In a single-centre cohort of 56 adults with chronic plaque psoriasis initiated on adalimumab or etanercept monotherapy between 2009 and 2011, drug and antidrug antibody levels were measured at the patients' routine clinic reviews (4, 12 and 24 weeks of treatment and the last available observation). Patients' responses at 6 months were stratified into responders [75% reduction in Psoriasis Area and Severity Index from baseline (PASI 75) or Physician's Global Assessment score of 'clear' or 'nearly clear'] and nonresponders (failure to achieve PASI 50).

RESULTS

After 4 weeks, adalimumab levels were significantly higher in responders compared with nonresponders (P = 0·003) and these higher levels were sustained at 12 and 24 weeks. Anti adalimumab antibodies were detected in 25% of nonresponders (two of eight patients, average 22·5 weeks' follow-up) and none of the responders (n = 23, average 26·1 weeks' follow-up). There was no significant association between etanercept levels and clinical response at 4 weeks (P = 0·317) and no antietanercept antibodies were detected. Lack of serum trough levels may have resulted in underestimation of the prevalence of antidrug antibodies.

CONCLUSIONS

Early adalimumab drug level monitoring at 4 weeks may be useful in predicting treatment response and potentially reduce drug exposure (and associated cost) with earlier review of treatment in those with low levels. No conclusions about the value of etanercept drug monitoring can be made due to the paucity of data. Larger studies are now required to assess the clinical utility and cost-effectiveness of these assays in personalizing therapy in psoriasis.

Psoriasis and cardiovascular disease: where is the risk?

In this issue, Dowlatshahi et al. publish results from their population-based study in Rotterdam showing that, despite an increase in body mass index and smoking, individuals with psoriasis have no increased risk of incident cardiovascular disease. These results should be interpreted with caution: the study included relatively small numbers of patients with psoriasis, most of whom had mild disease.

Topical therapies for the treatment of localized plaque psoriasis in primary care: a cost-effectiveness analysis

BACKGROUND

Topical therapies are a mainstay of psoriasis treatment, but they vary substantially in terms of cost.

OBJECTIVES

To determine the cost-effectiveness and optimal treatment sequence for psoriasis of the trunk, limbs and scalp.

METHODS

Probabilities of response from a network meta-analysis were used to determine the short-term efficacy of topical therapies. Longer-term outcomes, including relapse, were informed by published evidence and clinical opinion. Benefits of treatment were measured as quality-adjusted life years (QALYs). Direct costs included topical agents, primary and secondary care visits and second-line therapies for treatment failures.

RESULTS

For the trunk and limbs, initial treatment with a two-compound formulation (TCF) product containing vitamin D and potent corticosteroid provided the most QALYs, followed by separate morning and evening application of vitamin D and potent corticosteroid [two-compound application, TCA (am/pm)], and then twice-daily potent corticosteroids. The use of twice-daily potent corticosteroids was the most cost-effective first-line strategy (incremental cost-effectiveness ratio £ 20,000 per QALY), followed by TCA (am/pm) (£ 22,658 per QALY) and TCF product (£ 179,439 per QALY). For scalp psoriasis, initial treatment with very potent corticosteroids generated the most QALYs, followed by TCF product and then potent corticosteroids. Very potent corticosteroids were the most cost-effective treatment but, if too aggressive, potent corticosteroids were optimal followed by TCF product (£ 219,846 per QALY). The cost-effectiveness of second- and third-line topical agents varied with the assumptions made.

CONCLUSIONS

Potent corticosteroids, used alone or in combination with vitamin D, are the most cost-effective treatment for patients with psoriasis of the trunk and limbs. Potent or very potent corticosteroids are the most cost-effective treatment for patients with scalp psoriasis.

Tmem79/Matt is the matted mouse gene and is a predisposing gene for atopic dermatitis in human subjects

BACKGROUND

Atopic dermatitis (AD) is a major inflammatory condition of the skin caused by inherited skin barrier deficiency, with mutations in the filaggrin gene predisposing to development of AD. Support for barrier deficiency initiating AD came from flaky tail mice, which have a frameshift mutation in Flg and also carry an unknown gene, matted, causing a matted hair phenotype.

OBJECTIVE

We sought to identify the matted mutant gene in mice and further define whether mutations in the human gene were associated with AD.

METHODS

A mouse genetics approach was used to separate the matted and Flg mutations to produce congenic single-mutant strains for genetic and immunologic analysis. Next-generation sequencing was used to identify the matted gene. Five independently recruited AD case collections were analyzed to define associations between single nucleotide polymorphisms (SNPs) in the human gene and AD.

RESULTS

The matted phenotype in flaky tail mice is due to a mutation in the Tmem79/Matt gene, with no expression of the encoded protein mattrin in the skin of mutant mice. Matt(ft) mice spontaneously have dermatitis and atopy caused by a defective skin barrier, with mutant mice having systemic sensitization after cutaneous challenge with house dust mite allergens. Meta-analysis of 4,245 AD cases and 10,558 population-matched control subjects showed that a missense SNP, rs6684514, [corrected] in the human MATT gene has a small but significant association with AD.

CONCLUSION

In mice mutations in Matt cause a defective skin barrier and spontaneous dermatitis and atopy. A common SNP in MATT has an association with AD in human subjects.

Dysphagia therapy in stroke: a survey of speech and language therapists

BACKGROUND

Dysphagia is common after stroke, leading to adverse outcome. There is a paucity of high-quality evidence for dysphagia therapy, thus making it difficult to determine the best approaches to treatment. Clinical decisions are often based on usual practice, however no formal method of monitoring practice patterns exists.

AIMS

To determine speech and language therapists' (SLTs) approaches to direct dysphagia therapy with stroke patients in the UK and Ireland.

METHODS & PROCEDURES

A 24-item questionnaire was developed, piloted and delivered in a web-based cross-sectional survey targeting all SLTs working with stroke patients in the UK and Ireland.

OUTCOMES & RESULTS

A total of 138 SLTs responded from a range of clinical settings and levels of experience. There was variation in the responses to all questions. Respondents reported treating patients a median of once a day, 3 days a week for 15 min. The most commonly recommended direct exercises were supervised swallow trials (recommended 'frequently or always' by 73%). Despite most respondents having access to an instrumental swallowing assessment, over half reported rarely or never conducting one before recommending exercises. Most (93%) did not use a protocol for systematically progressing patients' exercises and only 37% reported using standardized outcome measures.

CONCLUSIONS & IMPLICATIONS

This survey gives valuable insight into the direct dysphagia therapy practices of SLTs based in the UK and Ireland working in stroke. It highlights discrepancies between reported approaches and recommendations from existing evidence and clinical guidelines. The variation in responses indicates a need to develop a consensus statement and further research to guide practice.

Identification of 15 new psoriasis susceptibility loci highlights the role of innate immunity

To gain further insight into the genetic architecture of psoriasis, we conducted a meta-analysis of 3 genome-wide association studies (GWAS) and 2 independent data sets genotyped on the Immunochip, including 10,588 cases and 22,806 controls. We identified 15 new susceptibility loci, increasing to 36 the number associated with psoriasis in European individuals. We also identified, using conditional analyses, five independent signals within previously known loci. The newly identified loci shared with other autoimmune diseases include candidate genes with roles in regulating T-cell function (such as RUNX3, TAGAP and STAT3). Notably, they included candidate genes whose products are involved in innate host defense, including interferon-mediated antiviral responses (DDX58), macrophage activation (ZC3H12C) and nuclear factor (NF)-κB signaling (CARD14 and CARM1). These results portend a better understanding of shared and distinctive genetic determinants of immune-mediated inflammatory disorders and emphasize the importance of the skin in innate and acquired host defense.

Infliximab for the treatment of psoriasis in the U.K.: 9 years' experience of infusion reactions at a single centre

BACKGROUND

Infliximab is an antitumour necrosis factor-α chimeric monoclonal antibody that is an established treatment for severe chronic plaque psoriasis. The recommended administration of a 2-h infusion followed by 2 h of monitoring is practised due to the potential occurrence of infusion reactions. However, accelerated infusions and shortened monitoring periods are used in patients with rheumatological disorders and inflammatory bowel disease without an increase in adverse events.

OBJECTIVES

To review the standard infliximab infusion protocol, the incidence of acute infusion reactions, the use of concomitant methotrexate and the clinical relevance of the 2-h postinfusion monitoring period.

METHODS

A retrospective case note and pharmacy database review of all infliximab infusions administered to patients with psoriasis at a tertiary dermatology centre was carried out.

RESULTS

Fifty-nine consecutive patients received a total of 858 infliximab infusions (range 1-43 infusions per patient) between January 2001 and June 2010. The incidence of infusion reactions was 1.5%, affecting 16.9% of patients and occurring between the first and eleventh infusions. Mild, moderate and severe acute reactions occurred in 0.6% (n=5), 0.3% (n=3) and 0.3% (n=3) of infliximab infusions, respectively. Thirty-three patients (56%) received concomitant systemic treatments during part of or throughout the infliximab treatment, including 24 (41%) on methotrexate (5-20 mg weekly). The prevalence of infusion reactions in patients receiving infliximab alone was 27% compared with 4% in those receiving concomitant methotrexate (P=0.05). All infusion reactions were managed as per our trust protocol with only one infusion reaction occurring in the postinfusion period (10 min after infusion completion).

CONCLUSION

The risk of infusion reactions in our cohort of patients was low, with the majority occurring early in the treatment cycle. Concomitant methotrexate may reduce this risk. A shortened postinfusion monitoring period can be safely considered.

Infliximab for the treatment of psoriasis in the U.K.: 9 years' experience of infusion reactions at a single centre

BACKGROUND

Infliximab is an antitumour necrosis factor-α chimeric monoclonal antibody that is an established treatment for severe chronic plaque psoriasis. The recommended administration of a 2-h infusion followed by 2 h of monitoring is practised due to the potential occurrence of infusion reactions. However, accelerated infusions and shortened monitoring periods are used in patients with rheumatological disorders and inflammatory bowel disease without an increase in adverse events.

OBJECTIVES

To review the standard infliximab infusion protocol, the incidence of acute infusion reactions, the use of concomitant methotrexate and the clinical relevance of the 2-h postinfusion monitoring period.

METHODS

A retrospective case note and pharmacy database review of all infliximab infusions administered to patients with psoriasis at a tertiary dermatology centre was carried out.

RESULTS

Fifty-nine consecutive patients received a total of 858 infliximab infusions (range 1-43 infusions per patient) between January 2001 and June 2010. The incidence of infusion reactions was 1.5%, affecting 16.9% of patients and occurring between the first and eleventh infusions. Mild, moderate and severe acute reactions occurred in 0.6% (n=5), 0.3% (n=3) and 0.3% (n=3) of infliximab infusions, respectively. Thirty-three patients (56%) received concomitant systemic treatments during part of or throughout the infliximab treatment, including 24 (41%) on methotrexate (5-20 mg weekly). The prevalence of infusion reactions in patients receiving infliximab alone was 27% compared with 4% in those receiving concomitant methotrexate (P=0.05). All infusion reactions were managed as per our trust protocol with only one infusion reaction occurring in the postinfusion period (10 min after infusion completion).

CONCLUSION

The risk of infusion reactions in our cohort of patients was low, with the majority occurring early in the treatment cycle. Concomitant methotrexate may reduce this risk. A shortened postinfusion monitoring period can be safely considered.

Demyelination during tumour necrosis factor antagonist therapy for psoriasis: a case report and review of the literature

Central nervous system (CNS) demyelination in a patient receiving tumour necrosis factor alpha (TNF-α) antagonist therapy in our practice prompted a search of the literature to assess the evidence for a causal relationship between TNF antagonist therapy and demyelination. We summarise clinical data extracted on 65 reported cases of CNS demyelination in patients receiving TNF antagonist therapy and show that the data are consistent with a drug-related aetiology given the temporal relationship between TNF antagonist initiation and symptoms, de-challenge-re-challenge phenomenon and the later age of disease onset compared with sporadic multiple sclerosis. Research on TNF signalling pathways also suggests a plausible causative role of TNF antagonist therapy in demyelination. However to date, controlled trial and pharmacovigilance data do not show an increased risk of demyelination in patients receiving TNF antagonist therapy. These data may be underpowered to exclude such a risk and pooled, collaborative data from multiple registries are warranted. Given the uncertainty in this area, clinicians should adhere to existing clinical guidance advising avoidance of TNF antagonist therapy in patients with a personal or family history of demyelination, and ensure all suitable patients are enrolled in long term safety registries in countries where these are established.

A systematic review of the literature on the treatment of pityriasis rubra pilaris type 1 with TNF-antagonists

BACKGROUND

Adult pityriasis rubra pilaris (PRP) type 1 is a rare chronic papulosquamous disorder with clinical and histological parallels with psoriasis. Treatment is challenging and recent case reports suggest a potential role for tumour necrosis factor (TNF) antagonists.

OBJECTIVES

Our objective was to systematically review the literature for evidence of efficacy of TNF antagonists in the treatment of adult PRP.

METHODS

We performed a systematic search of the Cochrane library, EMBASE, Pubmed and MEDLINE databases. We defined diagnosis of PRP, classified clinical response and whether this was clearly attributed to TNF-antagonists. We also reviewed disease, treatment duration and follow up.

RESULTS

Sixteen articles were selected for detailed review. From these, 12 articles (13 cases) met our predefined criteria and were included in the systematic review. The authors identified two more cases from their personal archive. A total of 15 evaluable cases were included for analysis. Twelve showed complete response (CR) (80%) to TNF-antagonists with a mean time to maximal response of 5 months. In 10 of the CR cases (83%) this was clearly attributable to TNF antagonist therapy.

CONCLUSION

These data indicate that TNF-antagonists may be of value in treating adult type 1 PRP refractory to other systemic agents but selective reporting bias, together with the lack of standard diagnostic criteria and established spontaneous resolution in PRP, prevent any firm recommendations on their place in management.

A validation study of multicenter diffusion tensor imaging: reliability of fractional anisotropy and diffusivity values

BACKGROUND AND PURPOSE

DTI is increasingly being used as a measure to study tissue damage in several neurologic diseases. Our aim was to investigate the comparability of DTI measures between different MR imaging magnets and platforms.

MATERIALS AND METHODS

Two healthy volunteers underwent DTI on five 3T MR imaging scanners (3 Trios and 2 Signas) by using a matched 33 noncollinear diffusion-direction pulse sequence. Within each subject, a total of 16 white matter (corpus callosum, periventricular, and deep white matter) and gray matter (cortical and deep gray) ROIs were drawn on a single image set and then were coregistered to the other images. Mean FA, ADC, and longitudinal and transverse diffusivities were calculated within each ROI. Concordance correlations were derived by comparing ROI DTI values among each of the 5 magnets.

RESULTS

Mean concordance for FA was 0.96; for both longitudinal and transverse diffusivities, it was 0.93; and for ADC, it was 0.88. Mean scan-rescan concordance was 0.96-0.97 for all DTI measures. Concordance correlations within platforms were, in general, better than those between platforms for all DTI measures (mean concordance of 0.96).

CONCLUSIONS

We found that a 3T magnet and high-angular-resolution pulse sequence yielded comparable DTI measurements across different MR imaging magnets and platforms. Our results indicate that FA is the most comparable measure across magnets, followed by individual diffusivities. The comparability of DTI measures between different magnets supports the feasibility of multicentered clinical trials by using DTI as an outcome measure.

Identification of a novel proinflammatory human skin-homing Vγ9Vδ2 T cell subset with a potential role in psoriasis

γδ T cells mediate rapid tissue responses in murine skin and participate in cutaneous immune regulation including protection against cancer. The role of human γδ cells in cutaneous homeostasis and pathology is characterized poorly. In this study, we show in vivo evidence that human blood contains a distinct subset of proinflammatory cutaneous lymphocyte Ag and CCR6-positive Vγ9Vδ2 T cells, which is rapidly recruited into perturbed human skin. Vγ9Vδ2 T cells produced an array of proinflammatory mediators including IL-17A and activated keratinocytes in a TNF-α- and IFN-γ-dependent manner. Examination of the common inflammatory skin disease psoriasis revealed a striking reduction of circulating Vγ9Vδ2 T cells in psoriasis patients compared with healthy controls and atopic dermatitis patients. Decreased numbers of circulating Vγ9Vδ2 T cells normalized after successful treatment with psoriasis-targeted therapy. Taken together with the increased presence of Vγ9Vδ2 T cells in psoriatic skin, these data indicate redistribution of Vγ9Vδ2 T cells from the blood to the skin compartment in psoriasis. In summary, we report a novel human proinflammatory γδ T cell involved in skin immune surveillance with immediate response characteristics and with potential clinical relevance in inflammatory skin disease.

Clinical and pharmacogenetic influences on response to hydroxychloroquine in discoid lupus erythematosus: a retrospective cohort study

The recommended systemic therapy of choice for discoid lupus erythematosus (DLE) is the 4-aminoquinolone antimalarial hydroxychloroquine. There is limited published information on the likelihood of clinical response and, in particular, what factors influence outcome. We conducted a multicenter observational and pharmacogenetic study of 200 patients with DLE treated with hydroxychloroquine. The primary outcome was clinical response to hydroxychloroquine. We investigated the effects of disease attributes and metabolizing cytochrome P450 (CYP) polymorphisms on clinical outcome. Although the majority of patients responded to hydroxychloroquine, a significant proportion (39%) either failed to respond or was intolerant of the drug. Cigarette smoking and CYP genotype did not have any significant influence on response to hydroxychloroquine. Moreover, multivariate analysis indicated that disseminated disease (odds ratio (OR): 0.21; 95% confidence interval (CI): 0.08-0.52; P<0.001) and concomitant systemic lupus erythematosus (SLE; OR: 0.06; 95% CI: 0.01-0.49; P = 0.009) were significantly associated with lack of response to hydroxychloroquine. These findings suggest that baseline lupus severity and SLE are predictors of response to hydroxychloroquine. A prospective study is now required to further investigate the relationship between disease activity and response to hydroxychloroquine. This will have the potential to further inform the clinical management of this disfiguring photosensitive disease.

How genetic variation affects patient response and outcome to therapy for psoriasis

Psoriasis is a prevalent chronic inflammatory condition that affects the skin. There are many treatments available for psoriasis but they are not universally effective and some have associated toxicities. Pharmacogenetics and pharmacogenomics explore the relationship between individual genetic variation and drug effect to allow targeted 'personalized' therapy for patients. There has been very limited pharmacogenetic research regarding psoriasis, with most limited to small retrospective case-control studies looking at single-nucleotide polymorphisms in candidate genes involved in drug pharmacokinetics. We review the pharmacogenetic investigation of treatments for psoriasis to date, including emerging pharmacogenomic studies. In addition, we discuss how such genetic data could be incorporated into routine clinical practice and future areas for development in this field.

A retrospective cohort study of the impact of biologic therapy initiation on medical resource use and costs in patients with moderate to severe psoriasis

BACKGROUND

Biologic therapy has become established as an important treatment option in patients with severe psoriasis, but is significantly more expensive in terms of drug costs than traditional treatment options. Relatively little is known about the total healthcare cost of treating severe psoriasis in daily clinical practice and what the budgetary impacts of such high-cost drugs are when compared with standard systemic therapy.

OBJECTIVES

To describe the impact of biologic therapy introduction on the use of medical resources, costs and where available, outcomes in patients with moderate to severe psoriasis.

METHODS

Data were extracted from case notes of a sequential patient cohort with psoriasis attending a tertiary referral severe psoriasis service and initiated on biologics (adalimumab, efalizumab, etanercept or infliximab) for treatment of their psoriasis. Data on hospital resource use (inpatient, outpatient, day ward, accident and emergency visits and phototherapy sessions) and drug usage (systemic nonbiologic and biologic psoriasis therapies and supportive drugs) were collected for 12 months prior to, and at least 6 months following initiation of biologic therapy. Outcome was measured using the Psoriasis Area and Severity Index (PASI). Differences in resource use and associated costs and outcomes, between 12 months before and after initiation of biologic therapy, were tested using Wilcoxon paired sign tests for continuous data and the McNemar test for categorical data. Confidence intervals (CI) around treatment costs were constructed using a 5000-sample bootstrap analysis.

RESULTS

The primary analysis population comprised 76 patients completing 12 months of biologic therapy: 71% males; mean age at time of study 47·3 years (range 23-74); mean duration of psoriasis 24·7 years (range 5·3-45·5). Significant reductions (P < 0·05) in the year following initiation of biologic therapy were observed for all hospital resource use categories, with mean annual costs reduced by £1682 (95% CI -3182 to -182·2; P = 0·05). Mean annual drug costs increased by £9456 (95% CI 8732-10,182; P < 0·001). Mean PASI fell by 8·9 points from 18·7 to 9·8 (95% CI -10·8 to -7·1; P < 0·001).

CONCLUSIONS

Total healthcare costs associated with treatment of severe psoriasis with biologic therapy are significantly greater than with traditional systemic therapy. However, some of these are offset by substantial reductions in the number and length of hospital admissions and use of photo- and systemic therapy, and result in significantly improved patient outcome (as inferred by improvement in PASI).