Acceptability of 'as needed' biologic therapy in psoriasis: insights from a multistakeholder mixed-methods study.

BACKGROUND: Biologic therapies have led to increasing numbers of patients with psoriasis who have clear or nearly clear skin. It is current practice to continue biologic therapy indefinitely in these patients, which contributes to a substantial long-term drug and healthcare burden. 'As needed' biologic therapy in psoriasis may address this; however, our understanding of patient and clinician perceptions of this strategy is limited. OBJECTIVES: The aim of this mixed-methods study was to gain insight into the perspectives of both patients and clinicians regarding the acceptability of an 'as needed' approach to biologic therapy in psoriasis, including potential barriers and enablers to implementation in routine care. METHODS: We first conducted UK-wide online scoping surveys of patients with psoriasis and dermatology clinicians to explore their views on 'as needed' biologic therapy. Using topic guides informed by these survey findings, we then carried out qualitative focus groups with patients and clinicians. Themes were identified using reflexive thematic analysis. RESULTS: Of 67 patients and 27 clinicians completing the scoping surveys, 67% (43 of 64 patients) and 78% (21 of 27 clinicians) supported the use of 'as needed' biologic therapy, respectively. Respondents highlighted advantages such as a reduction in healthcare burden and greater ownership of care. Challenges included logistics of 'as needed' drug provision and potential risks of disease flare and drug immunogenicity. Focus groups comprised 15 patients with psoriasis [9 female patients (60%), average disease duration 32 years (range 9-64)] and 9 dermatology clinicians [8 female clinicians (89%), average dermatology experience 20 years (range 8-33)]. Both patients and clinicians felt that an 'as needed' treatment approach will deliver a reduction in treatment burden and present an opportunity for patient-led ownership of care. Both groups highlighted the importance of ensuring ongoing access to medication and discussing the potential impact of psoriasis recurrence. Patient preferences were influenced by their lived experiences, particularly previous difficulties with medication delivery logistics and establishing disease control. Clinician perspectives were informed by personal experience of their patients adapting their own dosing schedules. Clinicians highlighted the importance of targeted patient selection for an 'as needed' approach, ongoing disease monitoring, and prompt reaccess to medications upon psoriasis recurrence. CONCLUSIONS: These data indicate that 'as needed' biologic therapy in psoriasis is acceptable for both patients and clinicians. Formal assessment of clinical effectiveness and cost-effectiveness is warranted to enable the real-world potential of this approach to be realized.

Psoriasis is a common skin disease that affects up to 2% of adults in the UK and causes red, scaly patches of skin. A new group of injectable medicines (called biologics) are extremely effective at controlling psoriasis. However, continuous use of these medicines can increase the risk of negative side-effects (such as infections). 'As needed' biologic therapy is when a person takes their biologic medication at the first sign of psoriasis recurrence (rather than continuously). This approach has potential to reduce the risks associated with taking biologics, while still maintaining good control of psoriasis symptoms. 'As needed' therapy has not been used in psoriasis yet, and so we wanted to know what people with psoriasis and healthcare professionals thought about this approach. We carried out national surveys of people with psoriasis and healthcare professionals to explore their views on 'as needed' biologic therapy. We also held group interviews to understand in more detail the positive aspects and potential issues with this approach. Overall, we found that an 'as needed' approach was viewed as acceptable by people with psoriasis and healthcare professionals. They thought this approach would reduce the negative impacts of treatment and allow patients to have more ownership of their care. Potential issues included the possibility of patients' psoriasis returning, as well as ensuring that they had access to medication quickly enough when needed. These findings indicate that 'as needed' biologic therapy in psoriasis is acceptable from both a patient and clinician perspective.

Psoriasis.

Psoriasis is a common, chronic papulosquamous skin disease occurring worldwide, presenting at any age, and leading to a substantial burden for individuals and society. It is associated with several important medical conditions, including depression, psoriatic arthritis, and cardiometabolic syndrome. Its most common form, chronic plaque or psoriasis vulgaris, is a consequence of genetic susceptibility, particularly in the presence of the HLA-C*06:02 risk allele, and of environmental triggers such as streptococcal infection, stress, smoking, obesity, and alcohol consumption. There are several phenotypes and research has separated pustular from chronic plaque forms. Immunological and genetic studies have identified IL-17 and IL-23 as key drivers of psoriasis pathogenesis. Immune targeting of these cytokines and of TNFα by biological therapies has revolutionised the care of severe chronic plaque disease. Psoriasis cannot currently be cured, but management should aim to minimise physical and psychological harm by treating patients early in the disease process, identifying and preventing associated multimorbidity, instilling lifestyle modifications, and employing a personalised approach to treatment.

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.

Systematic review of deep learning image analyses for the diagnosis and monitoring of skin disease.

Skin diseases affect one-third of the global population, posing a major healthcare burden. Deep learning may optimise healthcare workflows through processing skin images via neural networks to make predictions. A focus of deep learning research is skin lesion triage to detect cancer, but this may not translate to the wider scope of >2000 other skin diseases. We searched for studies applying deep learning to skin images, excluding benign/malignant lesions (1/1/2000-23/6/2022, PROSPERO CRD42022309935). The primary outcome was accuracy of deep learning algorithms in disease diagnosis or severity assessment. We modified QUADAS-2 for quality assessment. Of 13,857 references identified, 64 were included. The most studied diseases were acne, psoriasis, eczema, rosacea, vitiligo, urticaria. Deep learning algorithms had high specificity and variable sensitivity in diagnosing these conditions. Accuracy of algorithms in diagnosing acne (median 94%, IQR 86-98; n = 11), rosacea (94%, 90-97; n = 4), eczema (93%, 90-99; n = 9) and psoriasis (89%, 78-92; n = 8) was high. Accuracy for grading severity was highest for psoriasis (range 93-100%, n = 2), eczema (88%, n = 1), and acne (67-86%, n = 4). However, 59 (92%) studies had high risk-of-bias judgements and 62 (97%) had high-level applicability concerns. Only 12 (19%) reported participant ethnicity/skin type. Twenty-four (37.5%) evaluated the algorithm in an independent dataset, clinical setting or prospectively. These data indicate potential of deep learning image analysis in diagnosing and monitoring common skin diseases. Current research has important methodological/reporting limitations. Real-world, prospectively-acquired image datasets with external validation/testing will advance deep learning beyond the current experimental phase towards clinically-useful tools to mitigate rising health and cost impacts of skin disease.

Meeting Report: Psoriasis Stratification to Optimize Relevant Therapy Showcase.

A stratified medicine approach for the treatment of psoriasis promises greater certainty of clinical decision making through prediction of response on the basis of clinical, pharmacological, and -omics data from an individual patient. As yet, there is no predictive model for treatment response in routine clinical use for psoriasis. The Psoriasis Stratification to Optimise Relevant Therapy (PSORT) Consortium is a United Kingdom Medical Research Council‒funded, academic‒industrial stratified medicine consortium established with the objective of discovering the predictors and stratifiers of response of psoriasis to biologic therapies. A showcase meeting was convened and attended by 80 stakeholders at the Royal College of Physicians, London, United Kingdom on 18 November 2019. The purpose was to disseminate the research findings from the PSORT consortium discovered thus far. This report summarizes the presentations made on the day and the significant advances made by PSORT toward a stratified medicine approach to the management of psoriasis.

Analysis of the individual and aggregate genetic contributions of previously identified serine peptidase inhibitor Kazal type 5 (SPINK5), kallikrein-related peptidase 7 (KLK7), and filaggrin (FLG) polymorphisms to eczema risk.

BACKGROUND: Polymorphisms in the serine protease inhibitor gene serine peptidase inhibitor Kazal type 5 (SPINK5) and the serine protease kallikrein-related peptidase 7 gene (KLK7) appear to confer risk to eczema in some cohorts, but these findings have not been widely replicated. These genes encode proteins thought to be involved in the regulation of posttranslation processing of filaggrin (FLG), the strongest identified genetic risk factor for eczema to date. OBJECTIVES: We sought to clarify the individual risk of eczema conferred by the SPINK5 polymorphism rs2303067 (Glu420Lys) and a previously described insertion in the 3' untranslated region of KLK7 and to examine potential epistatic effects between these variants and FLG mutations. METHODS: Initially, we examined the effects of these polymorphisms and FLG in 486 unrelated patients from a German family-based study, an additional 287 German patients, and 418 unrelated Irish/English patients with eczema (n for 3 genes studied = 1191 vs 4544 control subjects). We then additionally studied the SPINK5 polymorphism and FLG mutations in 1583 patients with eczema from the Avon Longitudinal Study of Parents and Children cohort (sample size for 2 genes studied = 2774 vs 10,607 control subjects). RESULTS: No association was seen with the SPINK5 or KLK7 variants in the case-control analysis; however, a weaker effect was observed for the SPINK5 variant with maternal transmission in the family-based study. No interactions were seen between the polymorphisms in KLK7, SPINK5, and FLG. CONCLUSION: The SPINK5 420LysSer mutation confers a risk of eczema when maternally inherited but is not a major eczema risk factor. The KLK7 insertion appears to confer no risk of eczema. We found no interaction between the SPINK5 risk allele or the putative KLK7 risk allele and FLG mutations.

Comparison of Drug Discontinuation, Effectiveness, and Safety Between Clinical Trial Eligible and Ineligible Patients in BADBIR.

Importance: Patients with psoriasis enrolled in clinical trials of biologics may not be representative of the real-world population. There is evidence that patients ineligible for such trials have a greater risk of serious adverse events (SAEs), but the effect on drug discontinuation and effectiveness are unknown. Objective: To determine whether (1) drug discontinuation, (2) effectiveness, and (3) rates of SAEs differ in patients with psoriasis categorized as eligible or ineligible for clinical trials. Design, Setting, and Participants: An observational study using 157 dermatology centers in the United Kingdom and Republic of Ireland was carried out wherein we applied the eligibility criteria of clinical trials of biologic therapies for psoriasis to patients who were being followed up in the British Association of Dermatologists Biologic Interventions Register (BADBIR) and being prescribed biologics as part of standard clinical care. Patients with psoriasis registered to BADBIR who were taking etanercept (enbrel only; n = 1509), adalimumab (n = 4000), and ustekinumab (n = 1627) with at least 1 follow-up visit. Eligibility criteria were extracted from phase 3 licensing trials for etanercept, adalimumab, and ustekinumab for the treatment of moderate to severe psoriasis. Patients in BADBIR with a missing baseline Psoriasis Area and Severity Index (PASI) or baseline PASI value less than 10 (etanercept) or less than 12 (adalimumab; ustekinumab) but who would otherwise be eligible were investigated separately. Eligibility categories applied to BADBIR included: eligible, ineligible, insufficient baseline PASI only, and missing baseline PASI only. Main Outcomes and Measures: (1) Drug discontinuation: cumulative incidence at 12 months by stop reason per eligibility category and drug; (2) effectiveness: linear regression of absolute change in PASI from baseline to 6 and 12 months; and (3) SAEs: incidence rate ratio (IRR) at 12 months between eligibility categories per drug. Results: The mean (SD) age of the 7136 patients included in the analysis was 45 (13) years and 2924 (41%) were women and 4212 (59%) were men. Of 7136 patients, 839 (56%) etanercept, 2219 (56%) adalimumab, and 754 (46%) ustekinumab registrations were categorized as eligible. The most common reasons for ineligibility were diabetes (etanercept, 143 [9%]; ustekinumab, 201 [12%]) and nonchronic plaque psoriasis (adalimumab, 157 [4%]). Patients categorized as ineligible (etanercept, 367 [24%]; adalimumab, 282 [7%]; ustekinumab, 394 [24%]) achieved a smaller absolute change in PASI after 6 and 12 months (adalimumab, ustekinumab), and had significantly higher rates of SAEs compared with the eligible category (etanercept: IRR, 1.9; 95% CI, 1.4-2.6; adalimumab: IRR, 2.0; 95% CI, 1.5-2.6; ustekinumab: IRR, 2.8; 95% CI, 2.1-3.8). No significant differences in drug discontinuation were observed between categories. Conclusions and Relevance: Clinical trial effectiveness and safety outcomes are not representative of real-world patients in BADBIR patients categorized as ineligible for such trials.

Interaction between genetic control of vascular endothelial growth factor production and retinoid responsiveness in psoriasis.

Vascular endothelial growth factor (VEGF) promotes angiogenesis, and elevated levels are found in plaques of psoriasis. Two VEGF polymorphisms, +405 and -460, are associated with early-onset psoriasis and are close to the functional activator protein-1 site (+419) through which retinoids, an established systemic therapy for psoriasis, can block production of VEGF. We report that peripheral blood mononuclear cells (PBMCs) and epidermal keratinocytes (KC) from patients with psoriasis demonstrate differential, genotype-dependent, regulation of VEGF. For PBMCs, VEGF genotype distinguishes two groups of patients with psoriasis - "high and low VEGF producers" (P < 0.001). In contrast, KC production of VEGF is not genotype dependent. However, the effects of all-trans retinoic acid (RA) on cellular expression of VEGF are determined by both cell type and genotype. RA inhibits KC production of VEGF in a genotype-dependent manner (P < 0.005) whereas RA stimulates PBMCs production irrespective of VEGF genotype (P < 0.001). We also report that the -460 VEGF polymorphism appears to have a clinical pharmacogenetic role in predicting response or non-response of psoriasis to acitretin (P = 0.01). In future, determination of VEGF gene polymorphisms and thus individual patient VEGF "signatures" may be used as a prognostic factor for psoriasis susceptibility/severity and as a means for optimizing treatment response.

A randomized, investigator-masked clinical evaluation of the efficacy and safety of clobetasol propionate 0.05% shampoo and tar blend 1% shampoo in the treatment of moderate to severe scalp psoriasis.

The clinical benefit of currently available tar blend shampoos for the treatment of scalp psoriasis is restricted due to their limited efficacy, low cosmetic appeal and potential for carcinogenicity. This 4-week multicentre, randomized, parallel-group, investigator-masked study included 162 subjects and aimed to compare the efficacy, safety and cosmetic acceptability of clobetasol propionate 0.05% shampoo versus a currently marketed tar blend 1% shampoo in subjects with moderate to severe scalp psoriasis. Clobetasol propionate shampoo was superior to tar blend shampoo with respect to all efficacy variables tested (p<0.001): Total and Global Severity Score; erythema; plaque thickening; desquamation; pruritus; total scalp area involved; and the subject's global assessment of clinical improvement. Both treatments were safe and well-tolerated. Furthermore, more subjects indicated that clobetasol propionate shampoo was more cosmetically acceptable than tar blend shampoo. Clobetasol propionate 0.05% shampoo is a good alternative to tar blend shampoo in the treatment of moderate to severe scalp psoriasis.

Analysis of five chronic inflammatory diseases identifies 27 new associations and highlights disease-specific patterns at shared loci.

We simultaneously investigated the genetic landscape of ankylosing spondylitis, Crohn's disease, psoriasis, primary sclerosing cholangitis and ulcerative colitis to investigate pleiotropy and the relationship between these clinically related diseases. Using high-density genotype data from more than 86,000 individuals of European ancestry, we identified 244 independent multidisease signals, including 27 new genome-wide significant susceptibility loci and 3 unreported shared risk loci. Complex pleiotropy was supported when contrasting multidisease signals with expression data sets from human, rat and mouse together with epigenetic and expressed enhancer profiles. The comorbidities among the five immune diseases were best explained by biological pleiotropy rather than heterogeneity (a subgroup of cases genetically identical to those with another disease, possibly owing to diagnostic misclassification, molecular subtypes or excessive comorbidity). In particular, the strong comorbidity between primary sclerosing cholangitis and inflammatory bowel disease is likely the result of a unique disease, which is genetically distinct from classical inflammatory bowel disease phenotypes.

The major psoriasis susceptibility locus PSORS1 is not a risk factor for late-onset psoriasis.

PSORS1 is the major susceptibility locus for psoriasis vulgaris (PV) and lies within an approximately 200 kb segment of the major histocompatibility complex on chromosome 6p21.3. Alleles of candidate genes in this region including human leukocyte antigen (HLA)-C, alpha-helical coiled coil rod (HCR), and corneodesmosin (CDSN) show association with early-onset PV. Late-onset psoriasis (LOP) is defined as a disease with onset after 40 y of age and is typically sporadic. We assessed the role of PSORS1 in genetic susceptibility to LOP. Genotyping for HLA-C alleles and seven single nucleotide polymorphisms (SNP) within the genes HCR and CDSN was performed in LOP (n=145) and normal controls (n=309). Statistical analysis of allelic frequencies included calculation of odds ratio and chi2 comparisons. LOP demonstrated only a weak association to PSORS1 alleles HLA-Cw*6 (p=0.037), CDSN*5 (p=0.041), HCR*WC (p=0.013), and HCR SNP +325 (p=0.038). Patients with age of onset for psoriasis of 50 y or above provided no evidence of association with any of these alleles. These data suggest that the study cohort may include a number of subjects who harbor PSORS1 predisposition to early-onset psoriasis and yet do not present with disease by the age of 40 y. Thus this study demonstrates that PSORS1 is not a major inherited risk factor in the pathogenesis of LOP. These data suggest that the exclusion of LOP subjects from case-control studies will aid further delineation of the PSORS1 locus. Future genome-wide studies will be required to identify loci conferring risk for late-onset disease.

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.

Enhanced meta-analysis and replication studies identify five new psoriasis susceptibility loci.

Psoriasis is a chronic autoimmune disease with complex genetic architecture. Previous genome-wide association studies (GWAS) and a recent meta-analysis using Immunochip data have uncovered 36 susceptibility loci. Here, we extend our previous meta-analysis of European ancestry by refined genotype calling and imputation and by the addition of 5,033 cases and 5,707 controls. The combined analysis, consisting of over 15,000 cases and 27,000 controls, identifies five new psoriasis susceptibility loci at genome-wide significance (P<5 × 10(-8)). The newly identified signals include two that reside in intergenic regions (1q31.1 and 5p13.1) and three residing near PLCL2 (3p24.3), NFKBIZ (3q12.3) and CAMK2G (10q22.2). We further demonstrate that NFKBIZ is a TRAF3IP2-dependent target of IL-17 signalling in human skin keratinocytes, thereby functionally linking two strong candidate genes. These results further integrate the genetics and immunology of psoriasis, suggesting new avenues for functional analysis and improved therapies.

Genetic analysis of PSORS1 distinguishes guttate psoriasis and palmoplantar pustulosis.

The PSORS1 locus in the major histocompatibility complex region is the major genetic determinant for psoriasis vulgaris. Within the PSORS1 region reside at least three potential candidate genes for psoriasis susceptibility. Specific allelic variants of the genes HLA-Cw*6, HCR*WWCC, and CDSN*5 are strongly associated with psoriasis vulgaris and are in strong linkage disequilibrium with each other. We have genotyped the three psoriasis vulgaris susceptibility alleles of the PSORS1 locus in two clinical variants of psoriasis (guttate psoriasis and palmoplantar pustulosis) to study whether PSORS1 is also involved in the pathogenesis of these variants. We also asked whether these two clinical subgroups could help us to distinguish the causative gene within the high-risk PSORS1 haplotype. The association of guttate psoriasis with the three PSORS1 susceptibility alleles was similar and even stronger than seen with psoriasis vulgaris. Palmoplantar pustulosis, however, did not show association with any of the three candidate genes at this locus. Finally, no correlation with the age of onset for disease was observed. Our results show conclusively that psoriasis vulgaris and guttate psoriasis have a similar genetic basis for their association to PSORS1, whereas palmoplantar pustulosis appears to be a distinct disorder.

The IL23R A/Gln381 allele promotes IL-23 unresponsiveness in human memory T-helper 17 cells and impairs Th17 responses in psoriasis patients.

We and others have shown that the minor, nonconserved allele Gln381 of the Arg381Gln single-nucleotide polymorphism (rs11209026G>A) of the IL-23 receptor gene (IL23R) protects against psoriasis. Moreover, we have recently shown impaired IL-23-induced IL-17A production and STAT-3 phosphorylation in Th17 cells generated in vitro from healthy individuals heterozygous for the protective A allele (GA). However, the biological effect of this variant has not been determined in homozygous carriers of the protective A allele (AA), nor in psoriatic patients. Here we expand our functional investigation of the IL23R Arg381Gln gene variant to include AA homozygous individuals. By using isolated memory CD4+ T cells, we found attenuated IL-23-induced Th17 response in heterozygous individuals. Moreover, we found that AA homozygous individuals were strikingly unresponsive to IL-23, with minimal or no IL-17A and IL-17F production and failure of human memory Th17 cell survival/expansion. Finally, IL-23-induced Th17 response was also attenuated in age- and sex-matched GA versus GG psoriatic patients undergoing systemic treatment. Taken together, our data provide evidence for an allele-dosage effect for IL-23R Gln381 and indicate that common gene alleles associated with complex diseases might have biological effects of considerable magnitude in homozygous carriers.

The value of monitoring ciclosporin concentration 2 hours post-dose (C2) in dermatology: a prospective cohort study.

BACKGROUND: Ciclosporin (CsA) is an effective treatment for several inflammatory dermatoses, including psoriasis and eczema. In contrast to transplantation medicine, dermatologists do not routinely use CsA blood concentrations to guide therapy. OBJECTIVE: To determine the range of CsA levels at 2 hours after dosing (C2 levels) and whether these C2 levels had any relationship to clinically relevant parameters, such as CsA dose, serum creatinine, blood pressure, PASI (psoriasis area and severity index) or DLQI (dermatology life quality index). METHODS: A total of 18 patients on CsA maintenance therapy (cohort 1) and eight patients commencing on CsA (cohort 2) were included in the study. In cohort 1, CsA blood concentrations were measured at 2 hours post-dose on one occasion only, while in cohort 2, C2 levels were performed at baseline and at 4, 8 and 12 weeks after commencing CsA treatment. RESULTS: In cohort 1, a significant relationship between C2 levels and PASI was found. However, no relationship was found between C2 levels and CsA dose, blood pressure, or serum creatinine. In cohort 2, higher C2 levels were associated with lower PASI scores (p <0.05) and DLQI scores at 4 weeks (p = 0.014). CONCLUSION: We suggest that C2 levels may be beneficial in patients who are not responding well to CsA treatment in the loading phase.