Comparison of certolizumab pegol with other anticytokine agents for treatment of rheumatoid arthritis: a multiple-treatment Bayesian metaanalysis

A critical review of the United States regulatory pathways for determining the equivalence of efficacy between CT-P13 and original infliximab (Remicade®)

We evaluated the appropriateness of various equivalence margins for CT-P13, an infliximab biosimilar, in the PLANETRA clinical trial. The 95-95% method was used to independently determine an equivalence margin by pooling the historical clinical trials with original infliximab versus placebo, identified in a systematic literature search. The constancy assumption with the PLANETRA trial was assessed for each identified historical clinical trial to decide which study was scientifically justifiable to be pooled. A sensitivity analysis was performed for each study-pooling scenario. As a result, we identified two historical clinical trials that were deemed appropriate, whereas the PLANETRA trial pooled three additional studies to determine an equivalence margin, which was accepted by the United States Food and Drug Administration. However, those extra clinical trials did not meet the constancy assumption in baseline characteristics, methotrexate dose, and efficacy assessment time. The clinically more appropriate equivalence margin was 5.7 percentage points, which was much narrower than the 12 percentage points applied in the approval of CT-P13. In conclusion, the equivalence claim for CT-P13 to original infliximab in patients with rheumatoid arthritis did not appear to be supported when the constancy assumption was strictly assessed. The equivalence margin for biosimilars could be determined more conservatively.

Applied Bayesian Methods in the Rheumatic Diseases

The use of applied Bayesian methods is increasing in rheumatology. Using the Bayes theorem, past evidence is updated with new data. Preexisting data are expressed as a prior probability distribution or prior. New observations are expressed as a likelihood. Through explicit incorporation of preexisting data and new data, this process informs how this new information should change the way we think. In this article, the authors highlight the use of applied Bayesian methods in the study of rheumatic diseases.

Cost-utility analysis of certolizumab pegol in combination with methotrexate in patients with moderate-to-severe active rheumatoid arthritis in Greece

We aimed to evaluate the cost-effectiveness of certolizumab pegol (CZP), a pegylated fc-free anti-TNF, as add-on therapy to methotrexate (MTX) versus etanercept, adalimumab, or golimumab in patients with moderate-to-severe active rheumatoid arthritis (RA) not responding to the conventional synthetic disease-modifying anti-rheumatic drugs (csDMARDs). A Markov model (6-month cycle length) assessed health and cost outcomes of CZP versus other anti-TNFs recommended for RA in Greece over a patient's lifetime. Following discontinuation of first-line anti-TNF, patients switched to second anti-TNF and then to a biologic with another mode of action. Sequential use of csDMARDs followed third biologic. Clinical data and utilities were extracted from published literature. Analysis was conducted from third-party payer perspective in Greece. Costs (drug acquisition, administration, monitoring, and patient management) were considered for 2014. Results presented are incremental cost-effectiveness ratios (ICERs) per quality-adjusted life year (QALY). Probabilistic sensitivity analysis (PSA) ascertained robustness of base-case findings. Base-case analysis indicated that CZP+MTX was more costly and more effective compared with Etanercept+MTX (base-case ICER: €3,177 per QALY), whilst versus adalimumab/golimumab, CZP was dominant (less costly, more effective). For all comparisons, CZP treatment resulted in greater improvements in life expectancy and QALYs. PSA indicated that at the willingness-to-pay threshold of €34,000/QALY, CZP+MTX was associated with a 71.6, 97.9, or 99.2% probability of being cost-effective versus etanercept, golimumab, or adalimumab, respectively, in combination with MTX. This analysis demonstrates CZP+MTX to be a cost-effective alternative over Etanercept+MTX and a dominant option over Adalimumab+MTX and Golimumab+MTX for management of RA in Greece.

Comparative efficacy of biological agents in methotrexate-refractory rheumatoid arthritis patients: a Bayesian mixed treatment comparison

BACKGROUND/AIMS

Biological agents (biologics) targeting proinflammatory signaling have emerged as an important treatment option in rheumatoid arthritis (RA). Despite the clinical effectiveness of biologics for patients with RA who do not respond to 'traditional' disease-modifying anti-rheumatic drugs (DMARDs), there are concerns regarding their cost and long-term safety. In this study, we aimed to compare the efficacy of various biologics and traditional DMARDs in RA patients refractory to methotrexate (MTX).

METHODS

Four DMARDs (hydroxychloroquine, sulfasalazine, MTX, lef lunomide) and five anti-tumor necrosis factor drugs (adalimumab, etanercept, golimumab, inf liximab, and certolizumab) were selected. A systematic search of published studies was performed from inception through July 2013. Randomized trials of adults with MTX-refractory RA comparing two or more of the selected medications were included. Among 7,938 titles identified, in total, 16 head-to-head trials were selected. Two reviewers independently abstracted the study data and assessed methodological quality using the Cochrane Risk of Bias. Comparative efficacy was analyzed using a Bayesian mixed treatment comparison (MTC).

RESULTS

In total, 9, 4, and 11 studies were included for the outcome measures of the Health Assessment Questionnaire (HAQ), Disease Activity Score 28-erythrocyte sedimentation rate (DAS28-ESR) < 2.6 (remission), and American College of Rheumatology (ACR) 70 response, respectively. The treatments with the highest efficacy for each outcome measure were certolizumab combined with MTX, golimumab combined with MTX, and certolizumab combined with MTX, respectively.

CONCLUSIONS

Based on MTC analysis, using data from published randomized controlled trials, certolizumab and golimumab combined with MTX showed the highest efficacy in the three outcome measures (HAQ, DAS28-ESR < 2.6, and ACR 70 response) in MTX-refractory RA patients.

Tofacitinib versus Biologic Treatments in Moderate-to-Severe Rheumatoid Arthritis Patients Who Have Had an Inadequate Response to Nonbiologic DMARDs: Systematic Literature Review and Network Meta-Analysis

Objective. To compare the efficacy and tolerability of tofacitinib, an oral Janus kinase inhibitor for the treatment of rheumatoid arthritis (RA), as monotherapy and combined with disease-modifying antirheumatic drugs (DMARDs) versus biological DMARDs (bDMARDs) and other novel DMARDs for second-line moderate-to-severe rheumatoid arthritis (RA) patients by means of a systematic literature review (SLR) and network meta-analysis (NMA). Methods. MEDLINE®, EMBASE®, and Cochrane Central Register of Controlled Trials were searched to identify randomized clinical trials (RCTs) published between 1990 and March 2015. Efficacy data based on American College of Rheumatology (ACR) response criteria, improvements in the Health Assessment Questionnaire Disability Index (HAQ-DI) at 6 months, and discontinuation rates due to adverse events were analyzed by means of Bayesian NMAs. Results. 45 RCTs were identified, the majority of which demonstrated a low risk of bias. Tofacitinib 5 mg twice daily (BID) and 10 mg BID monotherapy exhibited comparable efficacy and discontinuation rates due to adverse events versus other monotherapies. Tofacitinib 5 mg BID and 10 mg BID + DMARDs or methotrexate (MTX) were mostly comparable to other combination therapies in terms of efficacy and discontinuation due to adverse events. Conclusion. In most cases, tofacitinib had similar efficacy and discontinuation rates due to adverse events compared to biologic DMARDs.

Tofacitinib Versus Biologic Treatments in Patients With Active Rheumatoid Arthritis Who Have Had an Inadequate Response to Tumor Necrosis Factor Inhibitors: Results From a Network Meta-analysis

PURPOSE

Tofacitinib is an oral Janus kinase inhibitor for the treatment of rheumatoid arthritis (RA). This analysis compared the efficacy and safety of tofacitinib with biologic disease-modifying antirheumatic drugs in patients with RA and a prior inadequate response (IR) to tumor necrosis factor inhibitors (TNFi).

METHODS

A systematic literature review identified 5 randomized placebo-controlled trials that evaluated tofacitinib or biologic disease-modifying antirheumatic drugs (bDMARDs) against placebo in patient populations with RA with a prior IR to TNFi. The definition of TNFi-IR varied across studies, and included patients with an IR or who had failed treatment with TNFi for any reason. A network meta-analysis was conducted comparing study data with regard to American College of Rheumatology response rates and Health Assessment Questionnaire-Disability Index improvement at weeks 12 and 24, rates of treatment withdrawal due to all causes; adverse events (AEs) and lack of efficacy; and rates of AEs, serious AEs, and serious infections.

FINDINGS

The 5 trials included a total of 2136 patients. Tofacitinib 5 mg twice daily combined with methotrexate was found to have relative risk estimates of American College of Rheumatology responses and change from baseline in Health Assessment Questionnaire-Disability Index score comparable with abatacept, golimumab, rituximab, and tocilizumab combined with conventional synthetic disease-modifying antirheumatic drugs. Withdrawal rates from trials due to all causes and AEs were comparable between treatments, and tofacitinib had a lower rate of withdrawals due to lack of efficacy. Rates of AEs and HAQ-DI were comparable between tofacitinib, other active treatments, and placebo. No serious infections were reported with tofacitinib during the placebo-controlled period (up to week 12) in this study population; rates of serious infection with other active treatments were generally low and similar to placebo.

IMPLICATIONS

During a 24-week period, tofacitinib had efficacy and rates of AEs comparable with currently available bDMARDs in the treatment of patients with RA who had a prior IR to TNFi. ClinicalTrials.gov identifiers: ORAL Step, NCT00960440; ATTAIN, NCT00124982; GO-AFTER, NCT00299546; RADIATE, NCT00106522; REFLEX, NCT00462345.

Modeling of the clinical and economic impact of a risk-sharing agreement supporting a treat-to-target strategy in the management of patients with rheumatoid arthritis in France

OBJECTIVES

To evaluate the cost-effectiveness of a Treat-to-Target strategy with certolizumab pegol in patients with rheumatoid arthritis in the context of a pay-for-performance agreement in which medication costs are refunded in case of discontinuation during the first 3 months of treatment.

METHODS

The Treat-to-Target strategy consisted of a systematic switch to second-line tumor necrosis factor (TNF)α inhibitor in case of an unmet ACR50 response at 3 months compared to current routine clinical practice. A reference cohort treated first-line with certolizumab pegol according to current practice without systematic switching was considered as the comparator. A decision-tree model was constructed to estimate clinical outcome (health assessment questionnaire-disability index or HAQ-DI score), time spent in ACR50 response (ACR 50), and direct costs of treatment over a 2-year period. HAQ scores were derived from American College of Rheumatology 50 (ACR50) responses. All TNFα inhibitors were assumed to have equivalent efficacy and tolerability. Costs were estimated at 2013 French retail prices (date of the pay-for-performance agreement).

RESULTS

The mean duration of an ACR50 response was 1.23 years in the Treat-to-Target strategy certolizumab pegol cohort vs 0.98 years in the reference cohort, resulting in a mean gain in HAQ at 24 months of 0.117. The Treat-to-Target strategy with a mix of TNFα inhibitors as second-line therapy was more expensive than the reference strategy in absolute terms, but this difference was entirely offset by the pay-for-performance agreement. The Treat-to-Target strategy was, thus, cost-neutral over a 2-year period after the payback of CZP cost for patients not achieving the target at 3 months.

CONCLUSIONS

In the context of a pay-for-performance agreement, the management of patients with rheumatoid arthritis using a Treat-to-Target strategy with certolizumab pegol in first line is dominant compared to standard use of this drug in the French setting in 2013.

Immunogenicity of infliximab and adalimumab: what is its role in hypersensitivity and modulation of therapeutic efficacy and safety?

INTRODUCTION

TNF-α inhibitors have demonstrated efficacy both as monotherapy and in combination with disease-modifying antirheumatic drugs (DMARDs) in the treatment of chronic inflammatory immune-mediated diseases such as rheumatoid arthritis, Crohn's disease, ankylosing spondylitis, psoriasis and/or psoriatic arthritis, and may be administered off-label to treat disseminated granuloma annulare systemic lupus erythematosus and systemic sclerosis. There are several TNF-α inhibitors available for clinical use including infliximab, adalimumab, golimumab, certolizumab pegol and etanercept.

AREAS COVERED

infliximab and adalimumab can induce the development of anti-infliximab (anti-IFX) and anti-adalimumab (anti-ADA) monoclonal antibodies (mAbs). In this review, we discuss the impact of anti-IFX and anti-ADA mAbs upon efficacy and safety of these biological agents.

EXPERT OPINION

IgG/IgE neutralizing antibodies against infliximab and adalimumab decrease the possibility of achieving a minimal disease activity state or clinical remission, decrease drug survival, increase the need for doctors to prescribe a higher drug dosage and, finally, favor the occurrence of adverse events. Concomitant administration of DMARDs such as methotrexate or leflunomide prevents the development of neutralizing Abs against infliximab and adalimumab.

Effect of combination therapy on joint destruction in rheumatoid arthritis: a network meta-analysis of randomized controlled trials

Background

Despite significant cost differences, the comparative effect of combination treatments of disease modifying anti-rheumatic drugs (DMARDs) with and without biologic agents has rarely been examined. Thus we performed a network meta-analysis on the effect of combination therapies on progression of radiographic joint erosions in patients with rheumatoid arthritis (RA).

Methods and Findings

The following combination drug therapies compared versus single DMARD were investigated: Double DMARD: 2 DMARDs (methotrexate, sulfasalazine, leflunomide, injectable gold, cyclosporine, chloroquine, azathioprin, penicillamin) or 1 DMARD plus low dose glucocorticoid (LDGC); triple DMARD: 3 DMARDs or 2 DMARDs plus LDGC; biologic combination: 1 DMARD plus biologic agent (tumor necrosis factor α inhibitor (TNFi) or abatacept or tocilizumab or CD20 inhibitor (CD20i)). Randomized controlled trials were identified in a search of electronic archives of biomedical literature and included in a star-shaped network meta-analysis and reported according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement protocol. Effects are reported as standardized mean differences (SMD). The effects of data from 39 trials published in the period 1989–2012 were as follows: Double DMARD: −0.32 SMD (CI: −0.42, −0.22); triple DMARD: −0.46 SMD (CI: −0.60, −0.31); 1 DMARD plus TNFi: −0.30 SMD (CI: −0.36, −0.25); 1 DMARD plus abatacept: −0.20 SMD (CI: −0.33, −0.07); 1 DMARD plus tocilizumab: −0.34 SMD (CI: −0.48, −0.20); 1 DMARD plus CD20i: −0.32 SMD (CI: −0.40, −0.24). The indirect comparisons showed similar effects between combination treatments apart from triple DMARD being significantly better than abatacept plus methotrexate (−0.26 SMD (CI: −0.45, −0.07)) and TNFi plus methotrexate (−0.16 SMD (CI: −0.31, −0.01)).

Conclusion

Combination treatment of a biologic agent with 1 DMARD is not superior to 2–3 DMARDs including or excluding LDGC in preventing structural joint damage. Future randomized studies of biologic agents should be compared versus a combination of DMARDs.

Certolizumab pegol (CDP870) for rheumatoid arthritis in adults

BACKGROUND

Tumour necrosis factor (TNF)-alpha inhibitors are beneficial for the treatment of rheumatoid arthritis (RA) in terms of reducing the risk of joint damage, improving physical function and improving quality of life. This Cochrane review is an update of a review of the treatment of RA with certolizumab pegol that was first published in 2011.

OBJECTIVES

To assess the clinical benefits and harms of certolizumab pegol (CDP870) in patients with RA who have not responded well to conventional disease-modifying anti-rheumatic drugs (DMARDs).

SEARCH METHODS

We searched the Cochrane Central Register of Controlled Trials (The Cochrane Library 2014, Issue 5), MEDLINE, EMBASE, Scopus, TOXLINE, Web of Knowledge; websites of the US Food and Drug Administration (FDA) and European Medicines Evaluation Agency (EMEA); reference lists of articles; and searched http/clinicaltrials.gov. The searches were updated from 2009 (date of last search for the original review) to 5 June 2014.

SELECTION CRITERIA

Randomised controlled trials that compared certolizumab pegol with any other agent including placebo or methotrexate (MTX) in adult patients with active RA despite current or prior treatment with conventional disease-modifying anti-rheumatic drugs (DMARDs), such as MTX.

DATA COLLECTION AND ANALYSIS

Two authors independently assessed search results, trial quality and extracted data. Disagreements were resolved by discussion or referral to a third author.

MAIN RESULTS

Eleven trials were included in this update. Ten (4324 patients) were included in the pooled analysis for benefits, five more than previously, and 10 (3711 patients) in the pooled analysis for harms, four more trials (1930 patients) than previously. The duration of follow-up varied from 12 to 52 weeks and the range of doses of certolizumab pegol varied from 50 to 400 mg given subcutaneously (sc). In phase III trials, the control was placebo plus MTX in five trials and placebo in four trials. The risk of bias of the included studies was assessed as low but there may have been a risk of attrition bias.Statistically significant improvements were observed at 24 weeks with the approved dose of 200 mg certolizumab pegol every other week, in 1) American College of Rheumatology (ACR) 50% improvement: 27% absolute improvement (95% CI 20% to 33%), NNT of 4 (95% CI 3 to 8), risk ratio (RR) 3.80 (95% CI 2.42 to 5.95); 2) the Health Assessment Questionnaire (HAQ): -12% absolute improvement (95% CI -9% to -14%), NNT of 6 (95% CI 5 to 8), mean difference (MD) - 0.35 (95% CI -0.43 to -0.26) (scale 0 to 3); 3) Disease Activity Score (DAS) remission improvement: absolute improvement 11% (95% CI 8% to 15%), NNT of 9 (95% CI 4 to 20), RR 8.47 (95% CI 4.15-17.28); and 4) radiological changes: erosion score (ES) absolute improvement -0.29% (95% CI -0.42% to -0.17%), NNT of 6 (95% CI 4 to 10), MD -0.67 (95% CI -0.96 to -0.38) (scale 0 to 230). Serious adverse events were statistically significantly more frequent for certolizumab pegol (200 mg every other week) with an absolute rate difference of 4% (95% CI 2% to 6%), NNTH of 32 (95% CI 17 to 88), Peto odds ratio (OR) 1.77 (95% CI 1.27 to 2.46). There was a statistically significant increase in all withdrawals in the placebo groups (for all doses and all follow-ups) with an absolute rate difference of -34% (95% CI -18% to -50%), NNTH of 4 (95% CI 3 to 5), NNTH of 4 (95% CI 3 to 5), RR 0.42 (95% CI 0.36 to 0.50); and there was a statistically significant increase in all withdrawals due to adverse events in the certolizumab groups (for all doses and all follow-up) with an absolute rate difference of 2% (95% CI 1% to 3%), NNTH of 55 (95% CI 27 to 238), Peto OR 1.66 (95% CI 1.15 to 2.37).The risk of bias was low and the quality of evidence was downgraded to moderate because of high rates of dropouts (> 20%) in most of the trials. We did not find any problems with inconsistency, indirectness, imprecision or publication bias.

AUTHORS' CONCLUSIONS

The results and conclusions did not change from the previous review. There is moderate-level evidence from randomised controlled trials that certolizumab pegol alone or combined with methotrexate is beneficial in the treatment of RA. Adverse events were more frequent with active treatment. We found a potential risk of serious adverse events.

Comparative efficacy of biologics as monotherapy and in combination with methotrexate on patient reported outcomes (PROs) in rheumatoid arthritis patients with an inadequate response to conventional DMARDs--a systematic review and network meta-analysis

Objective

To compare biologics as monotherapy or in combination with methotrexate (MTX) in terms of patient reported outcomes (PROs) in RA patients with an inadequate response to conventional DMARDs (DMARD-IR).

Methods

With a systematic literature review 17 RCTs were identified that evaluated adalimumab, certolizumab pegol, etanercept, golimumab, infliximab, abatacept, anakinra or tocilizumab. Treatment effects in terms of pain (0-100 mm), patient’s global assessment of disease activity (PGA; 0-100 mm), Health Assessment-Questionnaire (HAQ) disability index (DI; 0–3), and the physical component summary (PCS) of the SF36 Health Survey (0–100) at 24 weeks were combined by means of Bayesian network meta-analyses.

Results

With tocilizumab monotherapy, greater improvements in pain (difference = -11.1; (95% Credible Interval -21.3, -0.1)) and PGA (-10.3 (-20.4, 0.8)) were observed than with aTNF monotherapy. Tocilizumab was at least as efficacious as aTNF in HAQ-DI improvements (-0.16; (-0.37, 0.05)). aTNF + MTX (-17.9 (-23.1, -13.0) & -19.1 (-24.2, -14.4)), abatacept + MTX (-23.0 (-47.3, 1. 5) & -13.6 (-28.4, 2.0)) and tocilizumab + MTX (-16.0 (-26.3, -6.3) & -15.1 (-25.1, -5.7)) showed comparable reductions in pain and PGA relative to MTX. Efficacy of anakinra + MTX was much smaller as compared to other biologics. The greatest improvements in HAQ-DI relative to MTX were observed with aTNF + MTX (-0.30 (-0.37, -0.22)) and tocilizumab + MTX (-0.27 (-0.42, -0.12)), followed by abatacept + MTX (-0.21 (-0.37, -0.05)) and anakinra + MTX (-0.11 (-0.26, 0.05)). The improvements in SF36-PCS with abatacept + MTX, aTNF + MTX and tocilizumab + MTX were comparable. There is a >90% probability that aTNF + MTX results in a greater improvement in pain (-12.4), PGA (-16.1) and HAQ-DI (-0.21) than aTNF as monotherapy. Efficacy of tocilizumab + MTX showed comparable improvements in PROs as tocilizumab monotherapy.

Conclusions

Based on a network meta-analysis involving indirect comparison of trial findings, the following observations were made for DMARD-IR patients. In monotherapy, tocilizumab was associated with a greater improvement in pain and self-reported disease activity than aTNF, and was at least as efficacious regarding functional ability. The improvements in PROs with aTNF, abatacept and tocilizumab in combination with MTX were comparable. Improvements in PROs with tocilizumab as monotherapy were similar to that of tocilizumab + MTX, whereas aTNF as monotherapy was likely to be less efficacious than aTNF + MTX.

Efficacy and safety of infliximab-biosimilar compared to other biological drugs in rheumatoid arthritis: a mixed treatment comparison

OBJECTIVE

The aim of this meta-analysis was to compare the efficacy and safety of infliximab-biosimilar and other available biologicals for the treatment of rheumatoid arthritis (RA), namely abatacept, adalimumab, certolizumab pegol, etanercept, golimumab, infliximab, rituximab and tocilizumab.

METHODS

A systematic literature review of MEDLINE database until August 2013 was carried out to identify relevant randomized controlled trials (RCTs). Bayesian mixed treatment comparison method was applied for the pairwise comparison of treatments. Improvement rates by the American College of Rheumatology criteria (ACR20 and ACR50) at week 24 were used as efficacy endpoints, and the occurrence of serious adverse events was considered to assess the safety of the biologicals.

RESULTS

Thirty-six RCTs were included in the meta-analysis. All the biological agents proved to be superior to placebo. For ACR20 response, certolizumab pegol showed the highest odds ratio (OR) compared to placebo, OR 7.69 [95% CI 3.69-14.26], followed by abatacept OR 3.7 [95% CI 2.17-6.06], tocilizumab OR 3.69 [95% CI 1.87-6.62] and infliximab-biosimilar OR 3.47 [95% CI 0.85-9.7]. For ACR50 response, certolizumab pegol showed the highest OR compared to placebo OR 8.46 [3.74-16.82], followed by tocilizumab OR 5.57 [95% CI 2.77-10.09], and infliximab-biosimilar OR 4.06 [95% CI 1.01-11.54]. Regarding the occurrence of serious adverse events, the results show no statistically significant difference between infliximab-biosimilar and placebo, OR 1.87 [95% CI 0.74-3.84]. No significant difference regarding efficacy and safety was found between infliximab-biosimilar and the other biological treatments.

CONCLUSION

This is the first indirect meta-analysis in RA that compares the efficacy and safety of biosimilar-infliximab to the other biologicals indicated in RA. We found no significant difference between infliximab-biosimilar and other biological agents in terms of clinical efficacy and safety.

Current immunotherapy in rheumatoid arthritis

Rheumatoid arthritis is a common autoimmune disease primarily manifesting as chronic synovitis, subsequently leading to a change in joint integrity. Progressive disability and systemic complications are strongly associated with a decreased quality of life. To maintain function and health in patients with rheumatoid arthritis, early, aggressive and guided immunosuppressive therapy is required to induce clinical remission. Antirheumatic drugs are capable of controlling synovial inflammation and are therefore named 'disease-modifying antirheumatic drugs' (DMARDs). This article aims to bridge the beginning of DMARD therapy with agents such as methotrexate, leflunomide, sulfasalazine, injectable gold and (hydroxy)chloroquine with biological therapies, and with the new era of kinase inhibitors. Mechanisms of action, as well as advantages and disadvantages of DMARDs, are discussed with respect to the current literature and current recommendations.

The ACR20 and defining a threshold for response in rheumatic diseases: too much of a good thing

In the past 20 years great progress has been made in the development of multidimensional outcome measures (such as the Disease Activity Score and ACR20) to evaluate treatments in rheumatoid arthritis, a process disseminated throughout rheumatic diseases. These outcome measures have standardized the assessment of outcomes in trials, making it possible to evaluate and compare the efficacy of treatments. The methodologic advances have included the selection of pre-existing outcome measures that detected change in a sensitive fashion (in rheumatoid arthritis, this was the Core Set Measures). These measures were then combined into a single multidimensional outcome measure and such outcome measures have been widely adopted in trials and endorsed by the American College of Rheumatology (ACR) and the European League Against Rheumatism (EULAR) and regulatory agencies. The secular improvement in treatment for patients with rheumatoid arthritis has been facilitated in part by these major methodologic advancements. The one element of this effort that has not optimized measurement of outcomes nor made it easier to detect the effect of treatments is the dichotomization of continuous measures of response, creating responders and non-responder definitions (for example, ACR20 responders; EULAR good responders). Dichotomizing response sacrifices statistical power and eliminates variability in response. Future methodologic work will need to focus on improving multidimensional outcome measurement without arbitrarily characterizing some patients as responders while labeling others as non-responders.

Therapeutic human monoclonal antibodies in inflammatory diseases

Monoclonal antibodies (mAbs) are antibodies of a single antigen specificity produced by identical immune cells, i.e., clones of a common germ cell. They offer unprecedented opportunities to drug development because of their ability to target almost any cell surface or secreted molecule with remarkable efficacy and safety. In this chapter, the application of human mAbs in the treatment of inflammatory diseases is reviewed. We discuss in detail several mAb-based drugs such as anti-tumor necrosis factor (anti-TNF), anti-interleukin-1 (anti-IL-1) receptor, anti-IL-6 receptor, anti-α4 integrin subunit, and anti-CD20 agents, all of which have been documented by clinical trials to be efficacious and have been approved for the therapy of several inflammatory and immune diseases, including rheumatoid arthritis, Crohn's disease, ulcerative colitis, spondyloarthropathies, juvenile arthritis, psoriasis, psoriatic arthritis, and others. These novel drugs can be used either as a monotherapy or in combination with other conventional therapeutic modalities, particularly if the disease under treatment is refractory to therapy using solely conventional techniques. As a large variety of mAb-based agents targeting a plethora of cytokines, chemokines, adhesion and co-stimulatory molecules, receptors, as well as diverse cell types, are presently under investigation, the therapeutic armamentarium of the clinician is expected to greatly broaden in the near future, providing improved patient care for a wide range of devastating diseases of our times.

Targeting F box protein Fbxo3 to control cytokine-driven inflammation

Cytokine-driven inflammation underlies the pathobiology of a wide array of infectious and immune-related disorders. The TNFR-associated factor (TRAF) proteins have a vital role in innate immunity by conveying signals from cell surface receptors to elicit transcriptional activation of genes encoding proinflammatory cytokines. We discovered that a ubiquitin E3 ligase F box component, termed Fbxo3, potently stimulates cytokine secretion from human inflammatory cells by mediating the degradation of the TRAF inhibitory protein, Fbxl2. Analysis of the Fbxo3 C-terminal structure revealed that the bacterial-like ApaG molecular signature was indispensible for mediating Fbxl2 disposal and stimulating cytokine secretion. By targeting this ApaG motif, we developed a highly unique, selective genus of small-molecule Fbxo3 inhibitors that by reducing TRAF protein levels, potently inhibited cytokine release from human blood mononuclear cells. The Fbxo3 inhibitors effectively lessened the severity of viral pneumonia, septic shock, colitis, and cytokine-driven inflammation systemically in murine models. Thus, pharmacological targeting of Fbxo3 might be a promising strategy for immune-related disorders characterized by a heightened host inflammatory response.

Incorporating data from various trial designs into a mixed treatment comparison model

Estimates of relative efficacy between alternative treatments are crucial for decision making in health care. Bayesian mixed treatment comparison models provide a powerful methodology to obtain such estimates when head-to-head evidence is not available or insufficient. In recent years, this methodology has become widely accepted and applied in economic modelling of healthcare interventions. Most evaluations only consider evidence from randomized controlled trials, while information from other trial designs is ignored. In this paper, we propose three alternative methods of combining data from different trial designs in a mixed treatment comparison model. Naive pooling is the simplest approach and does not differentiate between-trial designs. Utilizing observational data as prior information allows adjusting for bias due to trial design. The most flexible technique is a three-level hierarchical model. Such a model allows for bias adjustment while also accounting for heterogeneity between-trial designs. These techniques are illustrated using an application in rheumatoid arthritis.

Why the findings of published multiple treatment comparison meta-analyses of biologic treatments for rheumatoid arthritis are different: an overview of recurrent methodological shortcomings

OBJECTIVES

To evaluate the quality of published multiple treatment comparison (MTC) meta-analyses on biologic disease modifying antirheumatic drugs (bDMARDs) for rheumatoid arthritis (RA), and to identify methodological issues that can explain the discrepancies in the findings of these MTCs.

METHODS

We searched MEDLINE for MTCs of bDMARDs for RA. Following the PRISMA guidelines, we extracted a large set of methodological items. These comprised of inclusion/exclusion criteria, information sources, reported results and outcomes measures, approaches to dealing with differing response profiles to available treatments, monotherapies versus combination therapies, and potential sources of heterogeneity.

RESULTS

We identified 13 published MTCs, of which nine were published since 2009. Despite similar stated eligibility criteria and objectives across MTCs, we identified major discrepancies in the estimated treatment effects, the inclusion of trials and analytic approaches. The number of included trials was typically much smaller than the number of eligible trials at the time of publication. Three out of six MTCs including patients of differing response profiles inappropriately combined DMARD-naive and DMARD-inadequate responder patients in the analyses. Four out of eight MTCs that considered both monotherapy and combination therapy (ie, concomitant DMARD) did not adjust for the potential effect modification. Half of the identified MTCs did not explore potential sources of heterogeneity, and the explored sources varied considerably. Last, most MTCs only included one or two efficacy outcomes (eg, ACR50) and only two considered health related quality of life outcomes (eg, HAQ).

CONCLUSIONS

The identified methodological shortcomings and inconsistencies most likely explain the observed discrepancies in findings across MTCs.

One target, different effects: a comparison of distinct therapeutic antibodies against the same targets

To date, more than 30 antibodies have been approved worldwide for therapeutic use. While the monoclonal antibody market is rapidly growing, the clinical use of therapeutic antibodies is mostly limited to treatment of cancers and immunological disorders. Moreover, antibodies against only five targets (TNF-α, HER2, CD20, EGFR, and VEGF) account for more than 80 percent of the worldwide market of therapeutic antibodies. The shortage of novel, clinically proven targets has resulted in the development of many distinct therapeutic antibodies against a small number of proven targets, based on the premise that different antibody molecules against the same target antigen have distinct biological and clinical effects from one another. For example, four antibodies against TNF-α have been approved by the FDA -- infliximab, adalimumab, golimumab, and certolizumab pegol -- with many more in clinical and preclinical development. The situation is similar for HER2, CD20, EGFR, and VEGF, each having one or more approved antibodies and many more under development. This review discusses the different binding characteristics, mechanisms of action, and biological and clinical activities of multiple monoclonal antibodies against TNF-α, HER-2, CD20, and EGFR and provides insights into the development of therapeutic antibodies.

Systematic review and meta-analysis of the efficacy and safety of existing TNF blocking agents in treatment of rheumatoid arthritis

Background and Objectives

Five-tumour necrosis factor (TNF)-blockers (infliximab, etanercept, adalimumab, certolizumab pegol and golimumab) are available for treatment of rheumatoid arthritis. Only few clinical trials compare one TNF-blocker to another. Hence, a systematic review is required to indirectly compare the substances. The aim of our study is to estimate the efficacy and the safety of TNF-blockers in the treatment of rheumatoid arthritis (RA) and indirectly compare all five currently available blockers by combining the results from included randomized clinical trials (RCT).

Methods

A systematic literature review was conducted using databases including: MEDLINE, SCOPUS (including EMBASE), Cochrane library and electronic search alerts. Only articles reporting double-blind RCTs of TNF-blockers vs. placebo, with or without concomitant methotrexate (MTX), in treatment of RA were selected. Data collected were information of patients, interventions, controls, outcomes, study methods and eventual sources of bias.

Results

Forty-one articles reporting on 26 RCTs were included in the systematic review and meta-analysis. Five RCTs studied infliximab, seven etanercept, eight adalimumab, three golimumab and three certolizumab. TNF-blockers were more efficacious than placebo at all time points but were comparable to MTX. TNF-blocker and MTX combination was superior to either MTX or TNF-blocker alone. Increasing doses did not improve the efficacy. TNF-blockers were relatively safe compared to either MTX or placebo.

Conclusions

No single substance clearly rose above others in efficacy, but the results of the safety analyses suggest that etanercept might be the safest alternative. Interestingly, MTX performs nearly identically considering both efficacy and safety aspects with a margin of costs.

Certolizumab in the long-term treatment of rheumatoid arthritis

Rheumatoid arthritis is the most common inflammatory arthritis and continues to have major long-term effects on quality of life. Early and intensive treatment has now become the norm in clinical practice with changes of medication dictated by measuring the presence of continued disease activity. Biologics, particular tumor necrosis factor inhibitors, have a crucial role in the management of very severe disease. Certolizumab is a relatively new tumor necrosis factor inhibitor which uses a novel strategy to neutralize TNF-alpha - the conjugation of tumor necrosis factor specific Fab antibody fragments to polyethylene glycol. Two Phase II and three Phase III randomized controlled trials have evaluated the efficacy and toxicity of certolizumab. More than 2000 patients were enrolled, and followed from 12-52 weeks. The number of patients achieving significant improvements with certolizumab, was indicated by the American College of Rheumatology with a 50% response rate. The risk ratios of achieving this response at 24 weeks was 6.01 (95% confidence interval [CI]: 3.84-9.40). At 52 weeks the risk ratio was 5.27 (95% CI: 3.19-8.71). The number of patients needed to treat, to obtain this benefit at 24 weeks was 4 (95% CI: 3-5). Certolizumab also had important clinical benefits in reducing erosive damage to joints, limiting disability, and enhancing other outcomes of importance to patients such as fatigue. The patient-related benefits were present from the early weeks of treatment. The clinical trials showed serious adverse events, including infections, which were more frequent for certolizumab. The most common adverse events comprised upper respiratory tract infections, hypertension, and nasopharyngitis. The balance of evidence suggests that certolizumab is equivalent to other tumor necrosis factor inhibitors, though no head-to-head trials have been undertaken. Having several effective treatments available, benefits patient choice, because the frequency and route of administration of these treatments varies. Furthermore, as intolerance and antibody development against existing biologics is not uncommon, having several agents allows opportunities to switch from one inhibitor to another.