Estimating the cost and health status consequences of treatment with TNF antagonists in patients with psoriatic arthritis

Model to Determine the Cost-Effectiveness of Screening Psoriasis Patients for Psoriatic Arthritis

OBJECTIVE

Screening psoriasis patients for psoriatic arthritis (PsA) is intended to identify patients at earlier stages of the disease. Early treatment is expected to slow disease progression and delay the need for biologic therapy. Our objective was to determine the cost-effectiveness of screening for PsA in patients with psoriasis in Canada.

METHODS

A Markov model was built to estimate the costs and quality-adjusted life years (QALYs) of screening tools for PsA in psoriasis patients. The screening tools included the Toronto Psoriatic Arthritis Screen, Psoriasis Epidemiology Screening Tool, Psoriatic Arthritis Screening and Evaluation, and Early Psoriatic Arthritis Screening Questionnaire (EARP) questionnaires. States of health were defined by disability levels as measured by the Health Assessment Questionnaire. State transitions were modeled based on annual disease progression. Incremental cost-effectiveness ratios and incremental net monetary benefits were estimated. Sensitivity analyses were undertaken to account for parameter uncertainty and to test model assumptions.

RESULTS

Screening was cost-effective compared to no screening. The EARP tool had the lowest total cost ($2,000 per patient per year saved compared to no screening) and the highest total QALYs (additional 0.18 per patient compared to no screening). The results were most sensitive to test accuracy and the efficacy of disease-modifying antirheumatic drugs (DMARDs). No screening was cost-effective (at $50,000 per QALY) relative to screening when DMARDs failed to slow disease progression.

CONCLUSION

If early therapy with DMARDs delays biologic treatment, implementing screening in patients with psoriasis in Canada is expected to represent a cost savings of $220 million per year and improve the quality of life.

Certolizumab pegol and secukinumab for treating active psoriatic arthritis following inadequate response to disease-modifying antirheumatic drugs: a systematic review and economic evaluation

BACKGROUND

Several biologic therapies are approved by the National Institute for Health and Care Excellence (NICE) for psoriatic arthritis (PsA) patients who have had an inadequate response to two or more synthetic disease-modifying antirheumatic drugs (DMARDs). NICE does not specifically recommend switching from one biologic to another, and only ustekinumab (UST; STELARA^®, Janssen Pharmaceuticals, Inc., Horsham, PA, USA) is recommended after anti-tumour necrosis factor failure. Secukinumab (SEC; COSENTYX^®, Novartis International AG, Basel, Switzerland) and certolizumab pegol (CZP; CIMZIA^®, UCB Pharma, Brussels, Belgium) have not previously been appraised by NICE.

OBJECTIVE

To determine the clinical effectiveness and cost-effectiveness of CZP and SEC for treating active PsA in adults in whom DMARDs have been inadequately effective.

DESIGN

Systematic review and economic model.

DATA SOURCES

Fourteen databases (including MEDLINE and EMBASE) were searched for relevant studies from inception to April 2016 for CZP and SEC studies; update searches were run to identify new comparator studies.

REVIEW METHODS

Clinical effectiveness data from randomised controlled trials (RCTs) were synthesised using Bayesian network meta-analysis (NMA) methods to investigate the relative efficacy of SEC and CZP compared with comparator therapies. A de novo model was developed to assess the cost-effectiveness of SEC and CZP compared with the other relevant comparators. The model was specified for three subpopulations, in accordance with the NICE scope (patients who have taken one prior DMARD, patients who have taken two or more prior DMARDs and biologic-experienced patients). The models were further classified according to the level of concomitant psoriasis.

RESULTS

Nineteen eligible RCTs were included in the systematic review of short-term efficacy. Most studies were well conducted and were rated as being at low risk of bias. Trials of SEC and CZP demonstrated clinically important efficacy in all key clinical outcomes. At 3 months, patients taking 150 mg of SEC [relative risk (RR) 6.27, 95% confidence interval (CI) 2.55 to 15.43] or CZP (RR 3.29, 95% CI 1.94 to 5.56) were more likely to be responders than patients taking placebo. The NMA results for the biologic-naive subpopulations indicated that the effectiveness of SEC and CZP relative to other biologics and each other was uncertain. Limited data were available for the biologic-experienced subpopulation. Longer-term evidence suggested that these newer biologics reduced disease progression, with the benefits being similar to those seen for older biologics. The de novo model generated incremental cost-effectiveness ratios (ICERs) for three subpopulations and three psoriasis subgroups. In subpopulation 1 (biologic-naive patients who had taken one prior DMARD), CZP was the optimal treatment in the moderate-severe psoriasis subgroup and 150 mg of SEC was optimal in the subgroups of patients with mild-moderate psoriasis or no concomitant psoriasis. In subpopulation 2 (biologic-naive patients who had taken two or more prior DMARDs), etanercept (ETN; ENBREL^®, Pfizer Inc., New York City, NY, USA) is likely to be the optimal treatment in all subgroups. The ICERs for SEC and CZP versus best supportive care are in the region of £20,000-30,000 per quality-adjusted life-year (QALY). In subpopulation 3 (biologic-experienced patients or patients in whom biologics are contraindicated), UST is likely to be the optimal treatment (ICERs are in the region of £21,000-27,000 per QALY). The optimal treatment in subpopulation 2 was sensitive to the choice of evidence synthesis model. In subpopulations 2 and 3, results were sensitive to the algorithm for Health Assessment Questionnaire-Disability Index costs. The optimal treatment is not sensitive to the use of biosimilar prices for ETN and infliximab (REMICADE^®, Merck Sharp & Dohme, Kenilworth, NJ, USA).

CONCLUSIONS

SEC and CZP may be an effective use of NHS resources, depending on the subpopulation and subgroup of psoriasis severity. There are a number of limitations to this assessment, driven mainly by data availability.

FUTURE WORK

Trials are needed to inform effectiveness of biologics in biologic-experienced populations.

STUDY REGISTRATION

This study is registered as PROSPERO CRD42016033357.

FUNDING

The National Institute for Health Research Health Technology Assessment programme.

Adalimumab, etanercept, infliximab, certolizumab pegol, golimumab, tocilizumab and abatacept for the treatment of rheumatoid arthritis not previously treated with disease-modifying antirheumatic drugs and after the failure of conventional disease-modifying antirheumatic drugs only: systematic review and economic evaluation

OBJECTIVES

Rheumatoid arthritis (RA) is a chronic inflammatory disease associated with increasing disability, reduced quality of life and substantial costs (as a result of both intervention acquisition and hospitalisation). The objective was to assess the clinical effectiveness and cost-effectiveness of seven biologic disease-modifying antirheumatic drugs (bDMARDs) compared with each other and conventional disease-modifying antirheumatic drugs (cDMARDs). The decision problem was divided into those patients who were cDMARD naive and those who were cDMARD experienced; whether a patient had severe or moderate to severe disease; and whether or not an individual could tolerate methotrexate (MTX).

DATA SOURCES

The following databases were searched: MEDLINE from 1948 to July 2013; EMBASE from 1980 to July 2013; Cochrane Database of Systematic Reviews from 1996 to May 2013; Cochrane Central Register of Controlled Trials from 1898 to May 2013; Health Technology Assessment Database from 1995 to May 2013; Database of Abstracts of Reviews of Effects from 1995 to May 2013; Cumulative Index to Nursing and Allied Health Literature from 1982 to April 2013; and TOXLINE from 1840 to July 2013. Studies were eligible for inclusion if they evaluated the impact of a bDMARD used within licensed indications on an outcome of interest compared against an appropriate comparator in one of the stated population subgroups within a randomised controlled trial (RCT). Outcomes of interest included American College of Rheumatology (ACR) scores and European League Against Rheumatism (EULAR) response. Interrogation of Early Rheumatoid Arthritis Study (ERAS) data was undertaken to assess the Health Assessment Questionnaire (HAQ) progression while on cDMARDs.

METHODS

Network meta-analyses (NMAs) were undertaken for patients who were cDMARD naive and for those who were cDMARD experienced. These were undertaken separately for EULAR and ACR data. Sensitivity analyses were undertaken to explore the impact of including RCTs with a small proportion of bDMARD experienced patients and where MTX exposure was deemed insufficient. A mathematical model was constructed to simulate the experiences of hypothetical patients. The model was based on EULAR response as this is commonly used in clinical practice in England. Observational databases, published literature and NMA results were used to populate the model. The outcome measure was cost per quality-adjusted life-year (QALY) gained.

RESULTS

Sixty RCTs met the review inclusion criteria for clinical effectiveness, 38 of these trials provided ACR and/or EULAR response data for the NMA. Fourteen additional trials contributed data to sensitivity analyses. There was uncertainty in the relative effectiveness of the interventions. It was not clear whether or not formal ranking of interventions would result in clinically meaningful differences. Results from the analysis of ERAS data indicated that historical assumptions regarding HAQ progression had been pessimistic. The typical incremental cost per QALY of bDMARDs compared with cDMARDs alone for those with severe RA is > £40,000. This increases for those who cannot tolerate MTX (£50,000) and is > £60,000 per QALY when bDMARDs were used prior to cDMARDs. Values for individuals with moderate to severe RA were higher than those with severe RA. Results produced using EULAR and ACR data were similar. The key parameter that affected the results is the assumed HAQ progression while on cDMARDs. When historic assumptions were used typical incremental cost per QALY values fell to £38,000 for those with severe disease who could tolerate MTX.

CONCLUSIONS

bDMARDs appear to have cost per QALY values greater than the thresholds stated by the National Institute for Health and Care Excellence for interventions to be cost-effective. Future research priorities include: the evaluation of the long-term HAQ trajectory while on cDMARDs; the relationship between HAQ direct medical costs; and whether or not bDMARDs could be stopped once a patient has achieved a stated target (e.g. remission).

STUDY REGISTRATION

This study is registered as PROSPERO CRD42012003386.

FUNDING

The National Institute for Health Research Health Technology Assessment programme.

EQ-5D in skin conditions: an assessment of validity and responsiveness

AIMS AND OBJECTIVES

This systematic literature review aims to assess the reliability, validity and responsiveness of three widely used generic preference-based measures of health-related quality of life (HRQL), i.e., EQ-5D, Health Utility Index 3 (HUI3) and SF-6D in patients with skin conditions.

METHODS

A systematic search was conducted to identify studies reporting health state utility values obtained using EQ-5D, SF-6D, or HUI3 alongside other HRQL measures or clinical indices for patients with skin conditions. Data on test-retest analysis for reliability, known group differences or correlation and regression analyses for validity, and change over time or responsiveness indices analysis were extracted and reviewed.

RESULTS

A total of 16 papers reporting EQ-5D utilities in people with skin conditions were included in the final review. No papers for SF-6D and HUI3 were found. Evidence of reliability was not found for any of these measures. The majority of studies included in the review (12 out of 16) examined patients with plaque psoriasis or psoriatic arthritis and the remaining four studies examined patients with either acne, hidradenitis suppurativa, hand eczema, or venous leg ulcers. The findings were generally positive in terms of performance of EQ-5D. Six studies showed that EQ-5D was able to reflect differences between severity groups and only one reported differences that were not statistically significant. Four studies found that EQ-5D detected differences between patients and the general population, and differences were statistically different for three of them. Further, moderate-to-strong correlation coefficients were found between EQ-5D and other skin-specific HRQL measures in four studies. Eight studies showed that EQ-5D was able to detect change in HRQL appropriately over time and the changes were statistically significant in seven studies.

CONCLUSIONS

Overall, the validity and responsiveness of the EQ-5D was found to be good in people with skin diseases, especially plaque psoriasis or psoriatic arthritis. No evidence on SF-6D and HUI3 was available to enable any judgments to be made on their performance.

Does disease activity add to functional disability in estimation of utility for rheumatoid arthritis patients on biologic treatment?

OBJECTIVE

Treatment in general is mostly directly aimed at disease activity, and measures such as the DAS28 might therefore present important additional information. Our aim was to develop and validate a model that uses a combination of disease activity (DAS28) and HAQs to estimate EuroQoL 5-dimension scale (EQ5D) utilities.

METHODS

Longitudinal data from a cohort study in RA patients from the Utrecht Rheumatoid Arthritis Cohort study Group (Stichting Reumaonderzoek Utrecht) who started treatment with a biologic drug were used for mapping and validation. All 702 observations, including DAS28, HAQ and EQ5D assessed at the same time points, were used. The observations were randomly divided into a subset for development of the model (n = 428 observations) and a subset for validation (n = 274). A stepwise multivariable regression analysis was used to test the association of DAS28 (components) and HAQ (domains) with EQ5D. Model performance was assessed using the explained variance (R(2)) and root mean square errors. Observed and predicted utility scores were compared to check for under- or overestimation of the scores. Finally, the performance of the model was compared with published mapping models.

RESULTS

Lower DAS28 score and HAQ items dressing and grooming, arising, eating, walking and activities were associated with higher EQ5D scores. The final model had an explained variance of 0.35 and a lower root mean square error as compared with other models tested. The agreement between predicted and observed scores was fair.

CONCLUSION

HAQ components estimate EQ5D better than total HAQ. Adding DAS28 to HAQ components does not result in better utility estimations.

Novel methods of measuring clinical outcomes from psoriasis and psoriatic arthritis clinical trials

Numerous instruments exist that measure the clinical and health related quality of life impact of psoriasis and psoriatic arthritis (PsA) in clinical trials. However, many of these instruments are not typically used in economic evaluations to inform decision problems facing health care decision makers. This study reviews the current state of psoriasis and PsA health outcome measures and evaluates their limitations in cost-effectiveness analyses (CEAs). We highlight the health related quality of life and clinical outcome measures that are typically used in CEAs, with special focus on studies with quality adjusted life years as a primary outcome measure. Despite the high prevalence of psoriasis and PsA health outcome measures in clinical trials, only a few are used in CEAs. The methods by which utilities are estimated from these measures vary across cost-effectiveness studies. These differences should be considered when conducting cost-effectiveness research in psoriasis and PsA.

High rate of disease remission in moderate rheumatoid arthritis on etanercept therapy: data from GISEA, the Italian biologics register

The aim of this study was to evaluate the clinical outcomes of etanercept in rheumatoid arthritis (RA) patients with moderate or severe disease activity. We analyzed data from the Italian biologics register Gruppo Italiano Studio Early Arthritides (GISEA) to investigate the rate of disease remission and functional improvement, based on the 28-Joint Disease Activity Score (DAS28) and the (Health Assessment Questionnaire (HAQ) score in RA patients with moderate or severe disease activity beginning etanercept therapy. Disease was defined as severe (H-RA) with DAS28 ≥5.1 and moderate (M-RA) with DAS28 ≥3.2 to 5.1 at baseline. Patients were considered in remission if DAS28 was ≤2.6, and HAQ ≤0.5 defined normal function. We enrolled 953 RA patients, 320 with M-RA and 633 H-RA. Age and disease duration were similar in the two cohorts, but H-RA patients had significantly more comorbidities (p < 0.01) and took significantly more disease-modifying antirheumatic drugs (p < 0.001) than M-RA patients. After 1 year, the percentage of patients achieving disease remission and normal function (DAS28 ≤2.6 plus HAQ ≤0.5) was higher in M-RA (21.4 %) than in H-RA patients (14.8 %, p = 0.007), regardless of the disease duration. Additionally, female gender (p = 0.006) and H-RA class (p = 0.002) negatively predicted disease remission at 1 year. However, the drug survival rate did not differ between the two subsets. This study confirms that etanercept was effective in the treatment of active RA, but best response, in terms of disease remission and normal function ability, was greater and easier to attain in M-RA patients. These findings may aid clinicians to choose the best strategy to treat RA.

Comparison of EuroQol-5D and short form-6D utility scores in multiethnic Asian patients with psoriatic arthritis: a cross-sectional study

OBJECTIVE

To compare EuroQol-5D (EQ-5D) and Short Form-6D (SF-6D) utility scores in multiethnic Asian patients with psoriatic arthritis (PsA).

METHODS

Consecutive patients fulfilling the Classification Criteria for Psoriatic Arthritis attending a rheumatology outpatient clinic were recruited and completed the EQ-5D and SF-6D questionnaires. Comparisons were performed by score distribution, mean, median, and the Outcome Measures in Rheumatology filter: i.e., truth, discrimination, and feasibility.

RESULTS

Eighty-six patients were enrolled (69 English-speaking and 17 Chinese-speaking; male:female ratio 0.91). The score distribution of SF-6D was normal, while that of EQ-5D was bimodal. A ceiling effect was observed in 20% of patients for EQ-5D and none for SF-6D. There were moderate correlations (Spearman's rho = 0.59, p < 0.0001) between the 2 scores, but poor agreements on scatterplot, intraclass correlation (ICC 0.43 and standardized ICC 0.21), and Bland-Altman plots. EQ-5D generated lower utility scores than SF-6D in the poorer health subgroup. SF-6D had stronger correlation with the general health status and other external measures of health; and it distinguished better between good and poor general health status, with better effect size and relative efficiency statistics. EQ-5D demonstrated higher patient acceptability.

CONCLUSION

EQ-5D and SF-6D instruments generated different utility scores in PsA. SF-6D may be superior because of normal scaling distribution and the absence of ceiling and floor effects. SF-6D also had better construct validity and better discrimination of poor health status. More studies are required for cost-utility analysis in PsA.

Disease burden of psoriatic arthritis compared to rheumatoid arthritis, Hungarian experiment

The objectives of this study were to assess the costs of psoriatic arthritis (PsA) in Hungary and to identify key cost drivers among demographic and clinical variables and to compare cost-of-illness of PsA and rheumatoid arthritis (RA). Cross-sectional retrospective survey of 183 consecutive patients from eight rheumatology centres was conducted. Mean direct medical, direct non medical, indirect and total costs were 1,876, 794, 2,904 and 5,574 euros/patient/year, respectively. Total costs were in significant linear relationship with health assessment questionnaire score and psoriatic area severity index. Costs of RA were higher in all domains than of PsA. Our study was the first from the Eastern European region that provides cost-of-illness data on PsA. Our study revealed that functional status and severity of skin symptoms were the key cost drivers. The costs of PsA in Hungary were lower than in the high-income European countries.

Summary of the International Federation of Psoriasis Associations (IFPA) meeting: a report from the GRAPPA 2009 annual meeting

The International Federation of Psoriasis Associations (IFPA) organized the second World Psoriasis and Psoriatic Arthritis Conference in Stockholm, Sweden, in June 2009. The 2009 collaborative multidisciplinary meeting attracted nearly 1000 clinicians and investigators from dermatology, rheumatology, basic science, and industry, as well as patients and leaders of patient organizations, from 68 countries. The major theme of the meeting was "Psoriasis - Skin and Beyond," and the primary aim was to highlight the significant effects of psoriasis and related comorbidities on patient function and quality of life. The annual meeting of GRAPPA (Group for Research and Assessment of Psoriasis and Psoriatic Arthritis) was held concurrently, and several GRAPPA members attended both meetings. Key presentations at IFPA that GRAPPA members believed were highlights of that meeting are summarized here.

Cost-effectiveness of infliximab for the treatment of active and progressive psoriatic arthritis

BACKGROUND

Despite its proven efficacy, infliximab is often considered to be an expensive treatment for patients with psoriatic arthritis.

OBJECTIVES

To estimate the cost-effectiveness of infliximab among patients with active and progressive psoriatic arthritis.

METHODS

A decision analytic model was constructed to simulate disease progression in hypothetical cohorts of patients with psoriatic arthritis receiving infliximab maintenance treatment. The primary response measure was change in Health Assessment Questionnaire score from a baseline estimated from mixed treatment models drawn from published clinical trials. Palliative care, comprising nonbiologic disease-modifying antirheumatic drugs, was used as a comparator. The primary outcome was quality-adjusted life years. The dose of infliximab was estimated for a range of 60 to 80 kg per patient body weight. The costs and outcomes were discounted at 3.5% for a period of 40 years. Uncertainty around the results was explored with probabilistic sensitivity analysis.

RESULTS

The mixed treatment comparison showed a significant reduction in Health Assessment Questionnaire score across all patients. The tumor necrosis factor α inhibitors were significantly superior to palliative care but comparable with one another. The incremental cost-effectiveness ratios for etanercept, adalimumab, and infliximab relative to palliative care were £17,327; £19,246; and £16,942 to £23,022, respectively, across all patients with psoriatic arthritis and £16,613; £18,170; and £15,788 to £21,736, respectively, in the subgroup with significant psoriasis.

CONCLUSION

Infliximab represents a cost-effective treatment option well within the National Institute for Health and Clinical Excellence threshold relative to palliative care. In light of equivalent outcomes with other tumor necrosis factor α inhibitors, its position in the treatment pathway is likely to be governed by treatment costs.

Understanding the relationship between the EQ-5D, SF-6D, HAQ and disease activity in inflammatory arthritis

BACKGROUND

The growth of economic analyses and in particular cost-utility analyses (CUA), which use the QALY as a measure of outcome, has heightened the interest in the methodologies used to calculate the QALY. The EQ-5D has produced quite different utility values from that of the SF-6D. This article seeks to understand these differences using a cohort of patients with inflammatory arthritis.

OBJECTIVE

To examine the relationship between the disease-specific measure, Health Assessment Questionnaire (HAQ) disability index (DI) and the preference-based measures, SF-6D, EQ-5D and European League Against Arthritis (EULAR) Disease Activity Score (DAS) in patients with rheumatoid arthritis (RA) and psoriatic arthritis (PsA).

METHODS

Patients with RA and PsA (n = 504) attending a tertiary rheumatology referral centre completed the HAQ, SF-6D and the EQ-5D before starting biological therapy and again 12 months later. The SF-36 was converted into a utility using the preference-based SF-6D. Clinical outcomes such as the DAS, joint counts and laboratory measures were also recorded. We calculated single index utility scores from the preference-based instruments using UK population norms. We used regression analysis to derive a mapping function and calculated utility scores from the HAQDI and the DAS 28.

RESULTS

The mean utility observed at baseline for RA was 0.43 for the EQ-5D and 0.54 for the SF-6D and for PsA was 0.49 for the EQ-5D and 0.57 for the SF-6D. The utility gain demonstrated by the EQ-5D was over twice that of the SF-6D. The EQ-5D scored 17% of the RA group as less than 0 (state defined as worse than death); 7% of this group remained less than 0 at follow-up. The distribution of the utility estimates was similar for both RA and PsA.

CONCLUSIONS

Our findings draw attention to the impact of states worse than death on the overall distribution for the EQ-5D derived utilities and how these impact on its use in practice. EQ-5D-derived QALY changes are over twice that of the SF-6D. The implication of this for decision makers is that cost-effectiveness evaluations for treatments in this disease class are likely to be very sensitive to the choice of utility measure.

Real-World Anti-Tumor Necrosis Factor Treatment in Rheumatoid Arthritis, Psoriatic Arthritis, and Ankylosing Spondylitis: Cost-Effectiveness Based on Number Needed to Treat to Improve Health Assessment Questionnaire

Objective.

To determine the effectiveness and cost-effectiveness of anti-tumor necrosis factor (anti-TNF) medications in a real-world environment for the treatment of rheumatoid arthritis (RA), psoriatic arthritis (PsA), and ankylosing spondylitis (AS) using the Health Assessment Questionnaire (HAQ).

Methods.

We created a database of patients with RA, PsA, or AS treated with anti-TNF agents (etanercept, infliximab, or adalimumab) at a large outpatient rheumatology clinic. Patient characteristics, baseline HAQ prior to treatment, subsequent yearly HAQ, and reasons for termination were collected. The cost based on percentage of patients achieving ≥ 0.2 improvement in HAQ (minimal clinically important difference, MCID) was calculated using the 2008 direct cost (Cdn) of the medication.

Results.

Data were available on 297 patients (206 with RA, 57 PsA, 34 AS). The mean age was 55 years, with 12 years of disease, and the mean baseline HAQ (standard error, SE) was 1.37 (0.04). The changes in HAQ (SE) at Years 1, 2, and 3 were −0.31 (0.04), −0.24 (0.06), and −0.27 (0.07) for annual cost to achieve MCID of $41,636, $42,077, and $42,147, respectively. The number needed to treat (NNT) was 1.94 (RA), 1.88 (PsA), and 2.30 (AS). There were no statistical differences between the diseases studied.

Conclusion.

We obtained data on the effectiveness and cost-effectiveness of anti-TNF drugs using the HAQ score, which is known to be an excellent predictor of work disability, morbidity, and mortality. HAQ scores decreased with treatment and were sustained throughout the 3–5 years of followup. The NNT of approximately 2 seems favorable and was similar between diseases.

Treatment strategies for early psoriatic arthritis

BACKGROUND

Until a few years ago, the early diagnosis of psoriatic arthritis (PsA) did not receive much attention, especially in view of the lack of drugs capable of altering the disease course. This changed with the introduction of the TNF-alpha-blocking agents, as a result of which the early diagnosis of PsA is now a topic of great interest.

OBJECTIVE

The aim of the study was to review the treatment for PsA in order to determine the optimal approach to managing early disease.

METHODS

The systematic review performed by members of GRAPPA (Group of Research and Assessment of Psoriasis and Psoriatic Arthritis) was integrated with data from more recent studies.

RESULTS/CONCLUSION

After making the diagnosis of PsA, the next step is to stage of the disease with the aim of establishing the prevalent manifestation (peripheral arthritis, peripheral enthesitis, axial involvement and dactylitis) and degree of severity (mild, moderate or severe) of the disease. Each patient should be treated according to the defined disease status following the suggested treatment algorithms.

The psoriatic arthritis cost evaluation study: a cost-of-illness study on tumour necrosis factor inhibitors in psoriatic arthritis patients with inadequate response to conventional therapy

OBJECTIVE

To evaluate costs, benefits and cost-effectiveness of anti-TNF agents in PsA patients with inadequate response to conventional treatment.

METHODS

A total of 107 patients, from nine Italian rheumatology centres, with different forms of PsA were given anti-TNF treatment, mainly etanercept (87%). Information on resource use, health-related quality of life, disease activity, function and laboratory values were collected at baseline and through out the 12 months of therapy. Cost (expressed in euro 2007) and utility (measured by EuroQol) before and after anti-TNF therapy initiation were compared in order to estimate the incremental cost per quality-adjusted life year (QALY) gained, and cost-effectiveness acceptability curve was calculated.

RESULTS

At the end of 12 months, there was a significant increase in direct cost due to an increase of drug cost caused by TNF inhibitors that was only partially offset by the decrease in indirect cost. In the last 6 months of therapy, the direct cost increased by euro5052, the cost for the National Health System (NHS) by euro5044 and the social cost by euro4638. However, a gain of 0.12 QALY resulted in a cost per QALY gained of euro40 876 for the NHS and of euro37 591 for the society. The acceptability curve showed that there would be a 97% likelihood that anti-TNF therapy would be considered cost-effective at willingness-to-pay threshold of euro60 000 per QALY gained.

CONCLUSION

Cost-effectiveness ratios are within the commonly accepted willingness-to-pay threshold. These results need to be confirmed in larger samples of patients.

Economic burden of psoriatic arthritis

Psoriatic arthritis (PsA) is a chronic autoimmune disease characterized by inflammatory arthritis in association with skin psoriasis (Ps). PsA may show a heterogeneous and variable clinical course, with involvement of peripheral and axial diarthrodial joints, periarticular structures such as entheses, as well as the skin and nails. Evidence is increasing that affected patients can have significant radiographic joint damage, functional impairment, reduced quality of life (QOL) and long-term work disability. The economic burden of PsA can be considerable. There is an increasing interest in pharmacoeconomic evaluations in PsA, driven mostly by the introduction of highly effective but expensive biologic agents, particularly inhibitors of the proinflammatory cytokine tumour necrosis factor (TNF)-alpha. Treatment with TNFalpha inhibitors results in not only substantial improvements in signs and symptoms of arthritis, but also improvements in all distinct sites of the disease, such as axial arthritis, dactylitis, enthesitis and skin disease. There is a dearth of published pharmacoeconomic evaluations in the field of PsA. The notable clinical efficacy of the TNFalpha inhibitors needs to be factored into a comprehensive assessment of their value. Further analyses are needed to optimize the use of the new biologic agents in PsA.

Tumor necrosis factor as a therapeutic target of rheumatologic disease

TNF-alpha is a crucial pro-inflammatory and immunoregulatory cytokine that is central to the pathogenesis of various inflammatory and autoimmune conditions. A number of controlled trials have shown effectiveness for TNF-alpha inhibitors in several diseases, in particular rheumatoid arthritis, ankylosing spondylitis, psoriatic arthritis and Crohn's disease. These agents may also be useful in additional autoimmune conditions. The introduction of TNF-alpha inhibitors has revolutionized the therapeutic approach and treatment paradigms especially for patients with rheumatoid arthritis. Despite extensive investigation, the full profile of their mechanisms of action remain incompletely understood. Optimal use of these agents requires consideration of their possible adverse effects. In addition to the presently available TNF-alpha blockers, other agents targeting this key mediator are under study. Recent advances and future directions in anti-TNF-alpha therapy are discussed in this paper.

Cost-effectiveness of psoriasis therapy with etanercept in Germany

BACKGROUND

We estimated the cost-effectiveness of intermittent therapy with etanercept in patients with moderate-to-severe plaque-type psoriasis in comparison to non-systemic therapy in Germany.

PATIENTS AND METHODS

We performed a cost-utility analysis using the endpoint costs per quality-adjusted life year gained (costs/QALY). For this purpose, we adapted a UK-based Markov model by means of resource use data that we derived from a German cost study. Efficacy data, information on frequency of adverse events and changes in quality of life were derived from three pooled clinical trials. We extrapolated the further course of the disease and its treatment over a 10 year course.

RESULTS

For patients with an initial Psoriasis Area and Severity Index (PASI) > 10 and a Dermatology Life Quality Index (DLQI) > 10 the incremental cost-effectiveness ratio (ICER) for etanercept compared to non-systemic therapy was 45,491 euro/QALY. For patients with PASI and DLQI > 15 costs/QALY were 32,058 euro and among patients with severe plaque psoriasis (DLQI and PASI > 20) 18,154 euro.

CONCLUSIONS

According to internationally accepted levels of cost-effectiveness thresholds, the intermittent treatment of (moderate to) severe plaque-type psoriasis with etanercept is a cost-effective measure within the German healthcare system.

Limited correlation between the Health Assessment Questionnaire (HAQ) and EuroQol in rheumatoid arthritis: questionable validity of deriving quality adjusted life years from HAQ

OBJECTIVES

There is growing emphasis on the cost-effectiveness of treating rheumatoid arthritis. Few trials directly record the health utility measures, like EuroQol, needed for economic analyses. Consequently linear regression methods have been used to transform Health Assessment Questionnaire (HAQ) scores into utility measures. The authors examined whether this is justified.

METHODS

The authors compared HAQ and EuroQol in cross-sectional and treatment change observational studies of rheumatoid arthritis patients; they also measured SF-36 and Nottingham Health Profiles.

RESULTS

In the cross-sectional study, HAQ and EuroQol scores were moderately inversely correlated (Spearman rank correlation, r = 0.76). HAQ showed a Gaussian distribution whereas EuroQol was bimodal. In the treatment change study, changes in HAQ and EuroQol were unrelated (r = 0.08); the changes showed similar Gaussian and bimodal distributions.

CONCLUSIONS

Not all patient-based measures are analogous, and evidence of clinical equivalence, especially in treatment response, is needed before data transformation is considered. Specifically, as HAQ and EuroQol are demonstrably not equivalent, economic evaluations of treatment cost effectiveness should not be based on EuroQol data transformed from HAQ. The use of such transformed data by regulatory bodies which determine drug availability means that the issue is no longer only of academic interest but a real clinical concern.

Economic issues with new rheumatologic therapeutics

PURPOSE OF REVIEW

Pharmacoeconomic evaluations are increasingly important in all aspects of medicine. In rheumatology, such studies have become all the more relevant following the introduction of highly effective biologic agents. Brought to the clinic initially for the treatment of rheumatoid arthritis, biologic agents have found expanded indication in other rheumatic diseases.

RECENT FINDINGS

Building upon a long tradition in rheumatology, recent studies have updated and expanded upon the costs of various rheumatic diseases. These studies set the stage for determining the value of newer therapies. As a result of the chronic nature of rheumatic diseases, pharmacoeconomic evaluations must be carried out over sufficiently long time frames. Therefore, methodologic issues continue to be an area of ongoing discussion. Finally, ongoing studies have estimated the cost-effectiveness of novel rheumatologic therapies, in particular the inhibitors of tumor necrosis factor. These studies have shown that in several clinical circumstances, tumor necrosis factor inhibitors can indeed have an incremental cost-efficacy within the range of generally accepted medical interventions. While many of these studies focused on rheumatoid arthritis, there is growing interest in pharmacoeconomic evaluations in other rheumatic diseases.

SUMMARY

Pharmacoeconomic evaluations are crucial to the optimal use of new therapies in rheumatology.

The comparative effectiveness of anti-TNF therapy and methotrexate in patients with psoriatic arthritis: 6 month results from a longitudinal, observational, multicentre study

OBJECTIVES

To compare the response to treatment with tumour necrosis factor (TNF) inhibitors and methotrexate (MTX) monotherapy in patients with psoriatic arthritis (PsA) within a real-life clinical setting.

METHODS

We analysed data from an ongoing longitudinal, observational multicentre study in Norway. Our data comprised 526 cases of patients with PsA who received either anti-TNF treatment (n = 146) or MTX monotherapy (n = 380) and were followed for at least 6 months with measures of disease activity, health status and utility scores. A propensity score was computed to adjust for channelling bias. The changes in measures of disease activity and health-related quality of life from baseline to 3- and 6-month follow-up were compared between the groups with adjustments for the baseline value of the dependent variable and the propensity score (analyses of covariance (ANCOVA)).

RESULTS

The groups were significantly different at baseline with respect to demographic and disease activity measures. The variables included in the propensity score were age, sex, number of previous disease modifying anti-rheumatic drugs (DMARDs), presence of erosive disease, treatment centre and investigator's global assessment. The adjusted changes at 6 months were significantly larger in the anti-TNF group for ESR, DAS-28, M-HAQ, patient's assessments of pain, fatigue and global disease activity on a visual analogue scale (VAS) and 4 out of 8 SF-36 dimensions.

CONCLUSIONS

Clinical improvement was superior with TNF inhibitors compared to MTX monotherapy in patients with PsA, when assessed in this setting of daily clinical practice.