Glycolysis aggravates methotrexate toxicity by fueling RFC1-controlled intestinal absorption in rheumatic rats

Methotrexate (MTX) is a first line anti-rheumatic drug. This study was designed to investigate the impact of rheumatoid arthritis (RA) conditions on its oral absorption, and clarify the relevance with changes of MTX absorption-related transporters in rheumatic models. MTX was orally administered to healthy, collagen-induced arthritis (CIA), and adjuvant-induced arthritis (AIA) rats. MTX plasma concentrations were determined by a validated liquid chromatography-mass spectrometry method. We found that intestinal MTX absorption was significantly increased in CIA/AIA rats versus healthy controls. This finding was supported by small intestine-based MTX uptake assay in vitro. Meanwhile, intestinal expression of both reduced folate carrier 1 (RCF1) and proton-coupled folate transporter (PCFT) remained unchanged. The everted intestinal sac assay confirms RFC1 is the key transporter accounting for intestinal MTX absorption, as its antagonist salicylazosulfapyridine showed potent capacity in reducing MTX uptake. No correlation between RA-related cytokines and RCF1 expression was observed in clinical samples. We further revealed that when cultured with AIA rat or RA patient serum, lactate and adenosine triphosphate (ATP) production as well as MTX uptake in MDCKII cells were significantly increased, and this increase was completely abrogated by ATP production-related metabolic inhibitors. Thanks to its inhibitory effects on MTX bioavailability, the glycolysis inhibitor shikonin diminished MTX-induced injuries of kidney and liver in AIA rats. These data demonstrate that glycolysis-driven high energy metabolism increases MTX absorption in rheumatic subjects, leading to the exacerbated toxicity. These findings will have important implications in optimizing MTX regimens for RA treatment with better efficacy and lower toxicity.

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.

Despite high costs, specialty drugs may offer value for money comparable to that of traditional drugs

Specialty drugs are often many times more expensive than traditional drugs, which raises questions of affordability and value. We compared the value of specialty and traditional drugs approved by the Food and Drug Administration (FDA) in the period 1999-2011. To do this, we identified published estimates of additional health gains (measured in quality-adjusted life-years, or QALYs) and increased costs of drug and health care resource use that were associated with fifty-eight specialty drugs and forty-four traditional drugs, compared to preexisting care. We found that specialty drugs offered greater QALY gains (0.183 versus 0.002 QALYs) but were associated with greater additional costs ($12,238 versus $784), compared to traditional drugs. The two types of drugs had comparable cost-effectiveness. However, the distributions across the two types differed, with 26 percent of specialty drugs--but only 9 percent of traditional drugs--associated with incremental cost-effectiveness ratios of greater than $150,000 per QALY. Our study suggests that although specialty drugs often have higher costs than traditional drugs, they also tend to confer greater benefits and hence may still offer reasonable value for money.

Nimesulide improves the symptomatic and disease modifying effects of leflunomide in collagen induced arthritis

Nimesulide is a COX-2 inhibitor used for symptomatic relief of rheumatoid arthritis. Leflunomide is an anti-pyrimidine used to manage the progression of rheumatoid arthritis. Herein we studied the influence of nimesulide and leflunomide combination in terms of disease symptoms and progression using collagen-induced arthritis model in mice, as a model for rheumatoid arthritis. Collagen induced arthritis was induced by immunization with type II collagen. Assessment of joint stiffness and articular hyperalgesia were evaluated using a locomotor activity cage and the Hargreaves method, respectively. Disease progression was assessed via arthritic index scoring, X-ray imaging, myeloperoxidase enzyme activity and histopathologic examination. Nimesulide induced only transient symptomatic alleviation on the top of decreased leucocytic infiltration compared to arthritis group. However, nimesulide alone failed to induce any significant improvement in the radiological or pathological disease progression. Leflunomide alone moderately alleviates the symptoms of arthritis and moderately retarded the radiological and pathological disease progression. Combination of nimesulide and leflunomide significantly improved symptomatic (analgesia and joint stiffness) and arthritic disease progression (radiological, pathological and Myeloperoxidase enzyme activity) in collagen induced arthritis animal model.

Including adverse drug events in economic evaluations of anti-tumour necrosis factor-α drugs for adult rheumatoid arthritis: a systematic review of economic decision analytic models

BACKGROUND

Anti-tumour necrosis factor-α drugs (anti-TNFs) have revolutionised the treatment of rheumatoid arthritis (RA). More effective than standard non-biological disease-modifying anti-rheumatic drugs (nbDMARDs), anti-TNFs are also substantially more expensive. Consequently, a number of model-based economic evaluations have been conducted to establish the relative cost-effectiveness of anti-TNFs. However, anti-TNFs are associated with an increased risk of adverse drug events (ADEs) such as serious infections relative to nbDMARDs. Such ADEs will likely impact on both the costs and consequences of anti-TNFs, for example, through hospitalisations and forced withdrawal from treatment.

OBJECTIVE

The aim of this review was to identify and critically appraise if, and how, ADEs have been incorporated into model-based cost-effectiveness analyses of anti-TNFs for adult patients with RA.

METHODS

A systematic literature review was performed. Electronic databases (Ovid MEDLINE; Ovid EMBASE; Web of Science; NHS Economic Evaluations Database) were searched for literature published between January 1990 and October 2013 using electronic search strategies. The reference lists of retrieved studies were also hand searched. In addition, the National Institute for Health and Care Excellence technology appraisals were searched to identify economic models used to inform UK healthcare decision making. Only full economic evaluations that had used an economic model to evaluate biological DMARDs (bDMARDs) (including anti-TNFs) for adult patients with RA and had incorporated the direct costs and/or consequences of ADEs were critically appraised. To be included, studies also had to be available as a full text in English. Data extracted included general study characteristics and information concerning the methods used to incorporate ADEs and any associated assumptions made. The extracted data were synthesised using a tabular and narrative format.

RESULTS

A total of 43 model-based economic evaluations of bDMARDs for adult RA were identified from 2,483 initially identified studies (2,473 published; ten technology appraisals). Of these, nine studies had incorporated the incidence and costs of ADEs and were critically reviewed. One study also explicitly estimated the potential consequences for patient utility. There was a general lack of detail specifically reporting on how ADEs were included in the economic models. Furthermore, there was substantial heterogeneity amongst the nine studies concerning the (i) application of risk-related terminology; (ii) method of incorporating the incidence, costs and consequences of ADEs; and (iii) ADE-related assumptions.

CONCLUSIONS

Model-based economic evaluations have played an integral role in healthcare reimbursement and funding decisions relating to anti-TNFs for adult patients with RA. However, current economic models have not routinely or systematically considered the direct costs or consequences of ADEs, which may bias the estimates of the relative cost-effectiveness of anti-TNFs. Omitting information on relevant costs and consequences of interventions for RA will affect the validity of the associated recommendations for informed decision making. To improve current practice it is recommended that (i) greater efforts be made to provide appropriate long-term safety data on the use of anti-TNFs in adult RA; (ii) empirical research be undertaken to identify and quantify the impact of, and possible methods for, including ADEs in economic models to inform future good practice guidelines; and (iii) economic modelling guidelines and reference cases be updated to explicitly identify ADEs as an important treatment outcome and address how they might be incorporated into economic models. Improved consideration of the possible implications of ADEs in economic models will ensure that healthcare decision makers are provided with reliable and accurate information with which to make efficient reimbursement and financing decisions.

The cost-effectiveness of TNF-inhibitors for the treatment of rheumatoid arthritis in Swedish clinical practice

OBJECTIVE

The objective was to estimate the cost-effectiveness of TNF-inhibitors for the treatment of rheumatoid arthritis in Swedish clinical practice, both as a first and second biological treatment, with or without the combination of conventional DMARDs. Further sub-group analysis of etanercept treatment was performed.

METHODS AND MATERIALS

Patient level data were obtained from three regions of the Swedish Rheumatology Registers. The dataset contained 2,558 patients who had started TNF-inhibitor treatment, 1,049 with etanercept as their first biological treatment. A total of 819 patients had switched to a second TNF-inhibitor, of which 425 to etanercept. A Markov cohort model was used in which health states of disease severity were classified according to HAQ and DAS28. Disease progression and discontinuation rates of TNF-inhibitors were based on the registry and for the comparator on published literature. Mortality, costs and utilities were based on Swedish data. The main analysis had a societal perspective over 20 years and efficacy was measured in quality-adjusted life-years (QALYs).

RESULTS

TNF-inhibitor treatment was associated with an increase in QALYs and an incremental cost compared to no biological treatment. The cost per QALY gained with the three TNF-inhibitors ranged from euro 50,000 to euro 120,000, with lower estimates for TNF-inhibitors used in combination with MTX and as a first biologic. At a progression of 0.045 for the comparator, most values remain within the accepted range for cost-effectiveness.

CONCLUSIONS

These results demonstrate that the cost per QALY for TNF-inhibitors was higher than in previous assessments based on registry data and that the results were sensitive to the HAQ progression of the comparator.

Similar biotherapeutic products: overview and reflections

Biotherapeutic products (BPs) have revolutionized medicine, changing the way we treat several pathologies such as autoimmune diseases and cancer, among others. Herein, we present an overview of similar BPs (SBPs), also called biosimilars, including the manufacturing process and regulatory aspects involved. The objective of developing an SBP is to manufacture a molecule that is highly similar to a reference BP by conducting a comparability exercise (CE) that can demonstrate similar safety and efficacy. This CE consists of quality, as well as nonclinical and clinical evaluation. A case-by-case analysis approach guided by scientific and objective standards must be the foundation for the SBP approval process. The establishment of a balance between a comprehensive CE for SBPs and their reference BPs, and the design of costeffective strategies to provide better access to BPs, should be the key goal for national regulatory authorities.

Economic evaluation of tocilizumab combination in the treatment of moderate-to-severe rheumatoid arthritis in Italy

OBJECTIVE

This study was designed to evaluate the cost utility of tocilizumab in rheumatoid arthritis (RA) patients, with inadequate responses to traditional disease-modifying anti-rheumatic drugs (tDMARDs) from a payer's perspective in Italy.

METHODS

An individual patient simulation model was used to project lifetime medical costs (payer's perspective) and quality-adjusted life-years (QALYs). Treatment sequences starting with tocilizumab or the most commonly prescribed biologics (etanercept, adalimumab, or infliximab) were compared. The addition of tocilizumab to standard of care, without the replacement of anti-tumor necrosis factor (TNF)-α treatments, was also evaluated. Patient characteristics, treatment efficacy, and quality-of-life data were based on three phase 3 tocilizumab clinical trials (TOcilizumab Pivotal Trial in Methotrexate Inadequate respONders [OPTION], Tocilizumab in cOmbination With traditional DMARD therapy [TOWARD], and TociLIzumab Safety and THE Prevention of Structural Joint Damage [LITHE]). Mixed-treatment comparison was used to estimate response probabilities. Resource utilization, treatment acquisition, administration, and monitoring costs were estimated using Italian secondary sources. Uncertainty in model parameters was evaluated by probabilistic sensitivity analysis.

RESULTS

Replacement of anti-TNF-α treatments with tocilizumab reduced total costs over a patient's lifetime (base-case analysis: tocilizumab sequence, €141,100 vs standard of care sequence, €143,500). Patients receiving tocilizumab realized more QALYs than patients receiving standard of care (9.8881 vs 9.3502 QALYs). Therefore, according to the base-case analysis, the tocilizumab sequence dominated the standard of care. In a sensitivity analysis, the model base-case result was robust to input changes. When tocilizumab was added to standard of care, without replacing anti-TNF-α treatments, the incremental cost-effectiveness ratio was €17,100 per QALY.

CONCLUSION

The analysis demonstrates that, in Italy, replacing another biologic DMARD with tocilizumab or adding tocilizumab to the current standard of care is a cost-effective strategy in the treatment of RA patients with inadequate responses to tDMARDs.

Cost effectiveness analysis of disease-modifying antirheumatic drugs in rheumatoid arthritis. A systematic review literature

The cost effectiveness of treatments that have changed the “natural history” of a chronic progressive disease needs to be evaluated over the long term. Disease-modifying antirheumatic drugs (DMARDs) are the standard treatment of rheumatoid arthritis (RA) and should be started as early as possible. A number of studies have shown that they are effective in improving disease activity and function, and in joint damage. Our review was focused on revision and critical evaluation of the studies including the literature on cost effectiveness of DMARDs (cyclosporine A, sulphasalazine, leflunomide, and methotrexate). The European League Against Rheumatism (EULAR) recommendations showed that traditional DMARDs are cost effective at the time of disease onset. They are less expensive than biological DMARDs and can be useful in controlling disease activity in early RA.

Serum levels of anti-CCP antibodies, anti-MCV antibodies and RF IgA in the follow-up of patients with rheumatoid arthritis treated with rituximab

Rheumatoid arthritis (RA) is characterized by the presence of circulating rheumatoid factor (RF) and anticitrullinated peptide antibodies (ACPA), which are positive in about 70-80% of patients. APCA have a higher specificity and therefore a higher diagnostic power than RF, but are less informative than RF in monitoring the course of the disease in patients under treatment. Recently, it has been reported that the anticitrullinated vimentin (a-MCV) antibody test can identify a particular subgroup of APCA that may be negative for anticyclic citrullinated peptide (a-CCP) antibodies. Concerning RF, the RF IgA isotype has been described as a more specific marker of erosive joint damage than total RF. The aim of our study was to monitor the levels of a-CCP, a-MCV, total RF and RF IgA in the follow-up of patients with RA treated with B-lymphocytedepletive rituximab (RTX), to detect any differences or peculiarities in patterns of these autoantibodies, especially in relation to their potential use as predictive markers of therapeutic response. We studied 30 patients with RA treated with RTX. All patients were previously unresponsive to at least 6 months of therapy with disease-modifying antirheumatic drugs (DMARDs; methotrexate, leflunomide, cyclosporine, chloroquine) and/or at least 6 months of therapy with anti-TNF biologics. The evaluation of response to RTX was made at month +6 using the EULAR criteria (DAS28). a-CCP, a-MCV, total RF and RF IgA were determined at baseline (before the first infusion of RTX) and after 1, 3 and 6 months. In serum samples obtained before treatment two cytokines essential for Blymphocyte proliferation, interleukin 6 (IL-6) and B-lymphocyte stimulator (BLyS) were also determined. In all patients a significant and consistent reduction in all the tested antibodies was found during follow-up, with no differences in respect of the degree of response to RTX. Of note, at baseline, generally a higher titre of all autoantibodies was seen in patients who then showed a better response to RTX. Finally, there were no differences in serum concentrations of IL-6 and BLyS in patients in relation to the presence or absence of the autoantibodies investigated, nor was there any significant correlation between the serum concentrations of the cytokines and the titres of the autoantibodies. Thus, neither a-MCV compared to a- CCP, nor RF IgA compared to routine total RF, provided any additional predictive information in the follow-up of patients with RA treated with RTX.

PGD2, IL-1-Family Members and Mast Cells

Cytokines are immunomodulatory and inflammatory compounds produced by many different cell types. The IL-1 family consists of at least eleven cytokines including IL-18 and IL-13 and are essential to the host defence against severe infections and mediate inflammation. IL-18 also enhances tumour rejection and has high capacity to augment the cytotoxicity of NK cells and T cells. IL-33 stimulates basophils and mast cells to produce cytokines and histamine independently of IgE. Mast cells play a crucial role in the development of allergy through the cross-linking of their surface receptors for IgE leading to degranulation and inflammation. Activated mast cells induce the generation of PGD2, detectable in 2–15 minutes after challenge, and LTC4. Here we review the interrelationship between PGD2, IL-1 family members and mast cells.

Cost-effectiveness treatment with Rituximab in patients with rheumatoid arthritis in real life

The cost-effectiveness of treatments that have the potential to change the "natural history" of a chronic progressive disease has to be evaluated over the long term. Cost-effectiveness estimates have been based on the concept that, with treatment, patients will not progress to the next level(s) of disease severity or will take a longer time to progress, thus avoiding or delaying the high costs and low utility associated with more severe disease. This analysis focused on the use of Rituximab in treating patients with moderate to severe RA for whom at least one anti-TNFα blocking agent had failed. The aim of our study was to evaluate the cost-effectiveness in 32 patients with rheumatoid arthritis in therapy with a single infusion of Rituximab 1,000 mg given on days 1 and 15 of each month for 1 year. After 6 months of treatment, we observed for all 32 patients a total quality-adjusted life year (QALY) gained of 11,840 with an average of 0.37 QALY for a single patient, a treatment cost of euro 5,610 and a QALY/cost ICER (incremental cost-effectiveness ratio) of euro 15,114. After 1 year of treatment, we observed data for 28 patients with a total QALY gained of 11,480 with an average of 0.41 QALY for a single patient, a treatment cost of euro 9,690 and a QALY/cost ICER (incremental cost-effectiveness ratio) of euro 23,696. The benefit of using Rituximab is cost-effectiveness with a QALY/gained under the acceptable threshold of euro 50,000 in our observational study. These are important data for discussion from the economic point of view when we choose a biologic therapy for rheumatoid arthritis in clinical practice.

Inflammatory Mediator Serotonin Receptor Gene (5-HTR3A) Expression Changes on Human Peripheral Blood Lymphocytes in Rheumatoid Arthritis

The 5-HT3 receptor is a pentameric ligand-gated cation channel located in the central and peripheral nervous system and on extraneuronal locations like lymphocytes, monocytes and fetal tissue. Serotonin receptor gene expressions and their alterations in RA diseases have not been reported. The aim of this study is to show whether the serotonin receptor gene expresses on peripheral blood lymphocytes and also to characterise the lymphocyte serotonin receptor expression profiles in patients suffering from rheumatoid arthritis (RA). In the present study, using RT-PCR technique, the research team investigated 5-HT3A receptor gene expression in peripheral blood lymphocyte cells (PBMC) of forty healthy individuals compared to forty RA patients. The PBMC was separated from whole blood by Ficoll-hypaque. Total cellular RNA was extracted and then cDNA was synthesized. The research team analyzed quantititavely gene expression profile by Real time-PCR using primer pairs specific for 5-HT3A receptor and for β-actin as internal control. Each PCR product of 5-HT3A receptor was confirmed by DNA sequencer ABI 3700 capillary system (Applied Biosystem, USA). The results showed that the 5-HT3A receptor gene is detected on the lymphocytes of both normal control and RA patients. There was a significant difference between 5-HT3A receptor expression profile in RA and that of healthy individuals. Moreover, no SNP-based change on sequenced fragments was observed. In conclusion, the present study indicated that not only human lymphocytes in normal individuals and patients express 5HT3A receptor, but the expression pattern of 5HT3A receptor gene is different between normal controls and RA patients. Moreover, after sequencing no changes in either controls or patients were observed. The above-mentioned changes can contribute to new information related to the pathogenesis of RA disease.

Inter-Relationship between Chemokines and Mast Cells

The inflammatory response is mediated by immunological and chemotactic factors, proteins of the complement system, histamine, serotonin, arachidonic acid products and cytokines. All these compounds, including cytokines/chemokines, are major contributors to the symptoms of inflammation. Cytokines/chemokines, commonly referred to as “biological response modifiers”, are relatively new compounds for possible use in stimulation of the immune response, and display a number of overlapping abilities to stimulate cells of various lineages and differentiation stages; nonetheless, most of these compounds are potent inflammatory mediators. Mast cell mediators are either contained within secretory granules or can be synthesized de novo and can be released upon activation by either a massive degranulation, or by a selective release of specific molecules. These cells accumulate in the stroma of a variety of inflamed and transformed tissues in response to locally produced chemotactic factors for immune-cells, such as RANTES and MCP-1. Here we describe some connections between mast cells and chemokines.