A dose adjustment in patients with rheumatoid arthritis not optimally responding to a standard dose of infliximab of 3 mg/kg every 8 weeks can be effective: a Belgian prospective study

Dose modification of anti-TNF in rheumatoid arthritis and estimated economical impact: a review of observational studies

Anti-TNF drugs indicated for the treatment of moderate-to-severe active rheumatoid arthritis (RA) presents similar efficacy, safety and potential toxicity profiles, with more than 10 years' treatment experience. Several pharmacoeconomic evaluations had demonstrated their favorable cost-effectiveness profile in RA patients, based on pivotal clinical studies data from different countries and perspectives. However, in clinical practice, individual profiles of patients and drugs leads to dose modifications that may be associated with substantial cost deviations. Here, we further discuss the effect of dose titration of these biological drugs in clinical practice over their RA cost-effectiveness profiles.

Ten-year Followup of Infliximab Therapy in Rheumatoid Arthritis Patients with Severe, Longstanding Refractory Disease: A Cohort Study

Objective.

Our study describes the 10-year followup data of the Belgian Expanded Access Program (EAP) for infliximab (IFX), which included patients with active rheumatoid arthritis who were refractory to methotrexate. The objectives of the study were to evaluate the continuation rate, reasons for discontinuation, and longterm disease control under IFX treatment, and to study baseline characteristics associated with longterm successful IFX therapy.

Methods.

Between February 2000 and September 2001, 511 patients were enrolled in the Belgian IFX EAP, and 507 effectively started IFX therapy. Previously reported data showed that 160 patients were still treated with IFX after 7 years of followup. We describe the therapy status, reasons for IFX discontinuation, and the level of disease activity of this subgroup after 10 years of followup. Baseline characteristics of the total EAP cohort were used to describe variables associated with longterm successful IFX treatment.

Results.

After 10 years of followup, 110 of the 507 patients (21.7%) were still receiving IFX treatment. In the 7-year to 10-year period, which is the focus of the current study, 16 patients were lost to followup and 34 patients discontinued IFX treatment, mainly because of loss of efficacy. Patients successfully treated with IFX for 10 years had lower baseline values for 28-joint Disease Activity Score (DAS28), patient pain scale, physician visual analog scale, and Health Assessment Questionnaire in comparison with the rest of the study cohort. The mean DAS28 level of the subgroup still taking IFX after 10 years was 2.55 ± 1.01.

Conclusion.

In the Belgian EAP, 21.7% of patients continued to receive maintenance IFX treatment after 10 years of followup. IFX provided good longterm disease control in these patients.

Abatacept for the treatment of rheumatoid arthritis: A review

BACKGROUND

Rheumatoid arthritis (RA) is a chronic, inflammatory disease affecting synovial joints. Patients with persistent, active disease have traditionally been treated with disease-modifying antirheumatic drugs (DMARDs) (eg, methotrexate) or biologic agents (eg, tumor necrosis factor [TNF] antagonists). However, patients may discontinue these treatments due to toxicity, infection, or lack of efficacy. Two additional biologic therapies-rituximab and abatacept-are currently available for TNF-antagonist inadequate responders. Abatacept is also indicated for inadequate responders to traditional DMARDs.

OBJECTIVES

The aims of this review was to provide an overview of the issues surrounding the treatment of RA patients experiencing inadequate responses to current treatment and to discuss the current and future impact of abatacept on the RA treatment armamentarium.

METHODS

The MEDLINE, EMBASE, and BIOSIS databases were searched (search dates: January 1, 2000-September 19, 2007) using the terms abatacept or CTLA-4 or Orencia with rheumatoid arthritis. Full text articles in English were selected for relevance, and only articles presenting primary clinical trial data from randomized, placebo-controlled, clinical trials of abatacept were included. This review focused on the Phase III trials of abatacept in methotrexate and/or TNF-antagonist inadequate responders, as these trials had the largest number of patients and the longest study durations.

RESULTS

The literature search initially yielded 848 papers. A total of 12 articles fulfilled the inclusion criteria. Abatacept is a novel agent that has been reported to reduce the signs and symptoms of RA in patients with active RA with an inadequate response to DMARDs and/or TNF-antagonist treatment. In both of these patient populations, treatment with abatacept was found to provide clinically meaningful health-related quality-of-life benefits, such as improvements in physical function, activity limitation, sleep, and fatigue. Abatacept was reported to have a consistent safety and tolerability profile, with a low rate (3.5%-4.2%) of discontinuation due to adverse events.

CONCLUSION

The efficacy and tolerability data from Phase III clinical trials suggest that abatacept is an effective and generally well tolerated treatment option for RA patients with an inadequate response to methotrexate and/or TNF antagonists.

Minimum effective dosages of anti-TNF in rheumatoid arthritis: a cross-sectional study

AIMS

To evaluate the modified dosages of anti-TNF in controlling disease activity in rheumatoid arthritis (RA) measured by DAS28-ESR.

PATIENTS AND METHODS

Cross-sectional study: RA patients treated with etanercept (ETN), adalimumab (ADA) or infliximab (IFX), at standard or modified doses.

MAIN VARIABLES

dosage, concomitant disease modifying drugs (DMARDs), DAS28-ESR.

RESULTS

195 RA patients included (79% women, mean age 58.1 years): ETN=81, ADA=56, IFX=58. Mean disease duration and time to first biological treatment was higher in IFX group (P=.01). Patients distribution by dosage: standard: ETN (72.8%), ADA (69.6%), IFX (27.6%); escalated: IFX (69%), ADA (5.4%), ETN (0%); reduced: ETN (27.1%), ADA (25%), IFX (3.4%). Concomitant DMARDs use was lower in ETN (58.2%) than ADA (66.07%) and IFX (79.31%). Higher proportion of responders (DAS28 ≤3.2) in ADA (65.3%) and ETN (61.7%) than IFX (48.3%).

CONCLUSIONS

RA clinical control can be preserved with modified anti-TNF dosages. Controlled prospective studies should be performed to define when therapy can be tailored and for which patients.

Disability outcomes and dose escalation with etanercept, adalimumab, and infliximab in rheumatoid arthritis patients: a US-based retrospective comparative effectiveness study

INTRODUCTION

Rheumatoid arthritis (RA) is a chronic disease that if left untreated may substantially impair physical functioning. Etanercept, infliximab, and adalimumab are tumor necrosis factor (TNF) blockers whose FDA-approved indications in the US include moderate to severe RA. TNF-blocker dose escalation has been well documented in the literature; however, the comparative effectiveness of these agents remains uncertain.

OBJECTIVE

To compare the effectiveness and dose escalation rates of etanercept, adalimumab, and infliximab in US community settings. We hypothesized that etanercept would be equivalent to infliximab and adalimumab in patient-reported disability 9-15 months after therapy initiation, and that fewer etanercept patients would experience dose escalation.

METHODS

This is a retrospective analysis of the Arthritis, Rheumatism, and Aging Medical Information System (ARAMIS). Adult patients with no biologic use 6 months before TNF-blocker initiation (index) and with Health Assessment Questionnaire Disability Index (HAQ-DI) scores at index and 9-15 months after index were analyzed (218 etanercept, 93 infliximab, and 40 adalimumab).

RESULTS

HAQ-DI change scores at 9-15 months did not differ by treatment (-0.12, -0.10, and -0.08 points for etanercept, infliximab, and adalimumab, respectively; p = 0.52). Dose increases were observed in 1.4% of etanercept, 10.8% of infliximab (p < 0.001), and 12.5% of adalimumab patients (p = 0.004). HAQ-DI change was associated with pre-index HAQ-DI score (p < 0.0001) and disease duration (p = 0.001).

CONCLUSIONS

Fewer etanercept patients escalated dose than infliximab or adalimumab patients, but improvements in functional disability were similar. These differences may have been influenced by package labeling, mode of administration, or other factors. RA treatment with infliximab and adalimumab in community settings, characterized by dose escalation, did not yield greater disability improvements compared to etanercept, which remained at a relatively stable dose. Uncontrolled treatment selection in this observational design may have influenced outcomes, and prior methotrexate treatment may partly explain disability improvements smaller than typically observed in clinical trials.

Adalimumab, etanercept, and infliximab utilization patterns and drug costs among rheumatoid arthritis patients

OBJECTIVES

To evaluate the utilization patterns of the anti-tumor necrosis factor (anti-TNF) agents Humira (adalimumab), Enbrel (etanercept), and Remicade (infliximab) in patients with rheumatoid arthritis (RA) and compare medication costs during the first year of treatment. (Humira is a registered trademark of Abbott Laboratories, IL; Enbrel is a registered trademark of Immunex Corporation, CA; and Remicade is a registered trademark of Janssen Biotech, Inc., PA).

METHODS

This retrospective analysis of medical and pharmacy claims included patients who were aged ≥18 years, had ≥2 RA diagnosis codes, and had ≥365 days of persistence with the index anti-TNF. Patients excluded had claims for anti-TNF agents within 6 months before the index date. Refill patterns for adalimumab and etanercept, number of infliximab infusions, time between infusions, and dose per infusion were analyzed for 12 months. Direct anti-TNF medication costs were compared among anti-TNFs for the initial treatment year.

RESULTS

Infliximab-treated patients (n = 457) were significantly older than adalimumab- (n = 337) or etanercept-treated patients (n = 902). Time between refills was longer than recommended for 28% and 30% of adalimumab and etanercept refill periods, respectively. Potential cumulative time without therapy was 33 days for adalimumab and 43 days for etanercept. Statistically significant differences in mean per-patient anti-TNF medication costs for the first year were reported for adalimumab, etanercept, and infliximab ($14,991, $13,361, and $18,139, respectively; p < 0.0001); however, a cost assessment using labeled dosing of the anti-TNF agents with optimal treatment compliance yielded comparable annual medication costs.

LIMITATIONS

This analysis only evaluated utilization patterns for selected anti-TNF agents and was not inclusive of other medications that patients may have been using for RA. Absolute patient adherence could not be assessed due to lack of information on how patients were self-administering adalimumab and etanercept or if samples of the agents were made available.

CONCLUSIONS

This study identified gaps in patients' refills compared with prescriber recommendations. The infliximab-treated group had infusion patterns consistent with prescribing information. Potential clinical and economic implications of dose attenuation with adalimumab and etanercept should be explored further.

Clinical response and tolerability to abatacept in patients with rheumatoid arthritis previously treated with infliximab or abatacept: open-label extension of the ATTEST Study

Objective

To assess the efficacy and safety of abatacept in biological-naive patients with rheumatoid arthritis and an inadequate response to methotrexate treated in the long-term extension (LTE) of the ATTEST trial.

Methods

Patients randomly assigned to abatacept, placebo or infliximab completing the 1-year double-blind period were eligible to receive abatacept ∼10 mg/kg in the open-label LTE. Efficacy to year 2 is presented for patients randomly assigned to abatacept or infliximab who switched to open-label abatacept. Safety data are presented for all patients entering LTE regardless of double-blind treatment.

Results

Of 431 patients randomly assigned, 79.8% remained on abatacept at year 2. At years 1 and 2, 19.7% and 26.1% of abatacept and 13.3% and 28.6% of infliximab-to-abatacept patients achieved disease activity score 28-defined remission (<2.6). Safety with abatacept during the cumulative study period was consistent with the double-blind experience, with no increase in adverse event incidence following the switch to abatacept.

Conclusion

In methotrexate-inadequate responders, abatacept efficacy was maintained over 2 years. For infliximab-to-abatacept patients, efficacy improvements were seen in year 2 after patients switched to abatacept. Switching directly from infliximab to abatacept was well tolerated. These data demonstrate that abatacept provides sustained responses and consistent safety, suggesting that switching from infliximab to abatacept is a viable treatment option.

When to initiate and discontinue biologic treatments for rheumatoid arthritis?

The introduction of biologic therapies heralded a new era in the treatment for chronic inflammatory autoimmune diseases of which rheumatoid arthritis is one of the most prevalent. From a scientific point of view, these therapies demonstrated that the targeting of individual cytokines or cell-surface markers is a very effective approach. For the physician, the appropriate selection of patients in whom these therapies should be initiated is critical, as is the even more contentious issue of whether these therapies can or should be discontinued in selected patients with excellent clinical responses. Whereas the former issue has been addressed in a large number of clinical trials and observational studies, the latter remains poorly investigated and is currently the subject of further study.

Baseline tumour necrosis factor alpha levels predict the necessity for dose escalation of infliximab therapy in patients with rheumatoid arthritis

OBJECTIVES

To investigate the possible role of baseline plasma tumour necrosis factor alpha levels (baseline-TNF) on the clinical response to infliximab in patients with rheumatoid arthritis (RA).

METHODS

Patients with RA refractory to methotrexate received 3, 6, or 10 mg/kg of infliximab every 8 weeks, in a randomised, double-blind manner: the RISING study. Clinical response (disease activity score in 28 joints based on C-reactive protein or American College of Rheumatology core set) at week 54 and serum infliximab levels were compared in three patient groups with low, intermediate, or high baseline-TNF (TNF-low, TNF-int, or TNF-high).

RESULTS

In TNF-low patients, the clinical response to different doses of infliximab was comparable, whereas TNF-int patients exhibited a dose-dependent trend. In contrast, TNF-high patients (approximately 13% of the total patients) had a clinical response to 10 mg/kg significantly better than the response to 3 and 6 mg/kg of infliximab. In TNF-high patients, the median trough serum levels of infliximab were below the detection limit (<0.1 μg/ml) at 3 and 6 mg/kg but were greater than 2 μg/ml at 10 mg/kg, whereas the levels were approximately 1 μg/ml for each dosage group in TNF-low patients.

CONCLUSION

In patients with RA, baseline-TNF is significantly associated with the clinical response to infliximab in patients with a high baseline-TNF. A higher dose of infliximab may be necessary in these patients, whereas lower doses of infliximab are sufficient for those with a low baseline-TNF. Baseline-TNF may be a useful measure for personalising the treatment of RA using infliximab.

Unresolved issues in biologic therapy for rheumatoid arthritis

The advent of biologic therapies for the treatment of rheumatoid arthritis (RA) has radically changed this therapeutic area. The currently available biologic agents have been studied extensively as part of their development and also during their subsequent years of use in clinical practice; as a result, the knowledge base regarding these therapeutics is very large. Nonetheless, a number of important questions remain and some key issues are still incompletely understood. In this Review, I discuss a number of these unresolved issues, including: the correct placement of biologic therapies in the long-term evolution of the RA disease process, and the expectations associated with such use; comparisons of therapeutic strategies that include conventional as well as biologic agents; optimal dosing of biologic agents; the elusive goal of personalized therapy; and an appraisal of the real impact of biologic therapy on patients' lives. It is concluded that, despite these unresolved issues, important progress has been made and many additional advances in our understanding can be expected during the coming years.

Trough infliximab concentrations predict efficacy and sustained control of disease activity in rheumatoid arthritis

Infliximab is a chimeric monoclonal antibody that binds to human tumor necrosis factor alpha and is approved for refractory rheumatoid arthritis. We studied the association between infliximab concentration and long-term control of disease activity in patients with rheumatoid arthritis treated on a routine basis both in cross-sectional analysis and over the long term. Trough serum infliximab concentrations were measured in patients with rheumatoid arthritis receiving infliximab infusions during the period August to October 2006. Disease activity was assessed by the Disease Activity Score for 28 Joints (DAS28) and usual biologic markers. During a 42-week follow-up period, patients were classified into two groups: those continuing with the same or lower doses of infliximab (Group A = treatment success) and those who switched to another biopharmaceutical or required an increase in infliximab dose (Group B = treatment failure). Treatment maintenance for Group A was analyzed by categories of infliximab concentration at baseline and compared by the log rank test. In 28 patients, C-reactive protein and infliximab concentrations were inversely related. Infliximab concentration in patients with low disease activity (DAS28 3.2 or less) was higher than in those with persistent active disease (DAS28 greater than 3.2); median values were 3.26 and 0.16 mg/L, respectively (P < 0.01). Analysis after 42 weeks showed that patients in Group A had higher infliximab concentrations at baseline than those with treatment failure (P < 0.01). In rheumatoid arthritis, infliximab concentration is predictive of sustained efficacy with the same infliximab regimen and should be considered on a routine basis.

Seven-year follow-up of infliximab therapy in rheumatoid arthritis patients with severe long-standing refractory disease: attrition rate and evolution of disease activity

Introduction

This study is based on the results from a Belgian expanded access program in which patients with active refractory and erosive rheumatoid arthritis (RA) were treated with intravenous infusions of infliximab in combination with methotrexate. The objectives of this study were to evaluate the continuation rate of infliximab and its clinical effect over a 7-year period and to document the reasons for discontinuation.

Methods

Between 2000 and 2001, 511 patients with severe and refractory RA were enrolled and treated with infliximab. After 7 years, apart from routine clinical follow-up, treating rheumatologists were asked to complete a questionnaire designed specifically for the present study to evaluate the current therapy with infliximab, the level of disease activity (Disease Activity Score in 28 joints [DAS28]) and the reasons for infliximab discontinuation.

Results

After 7 years, 160 of 511 patients (31%) were still on infliximab treatment. The major reasons for infliximab discontinuation included lack of efficacy (104 patients), adverse events (107 patients) and elective change of therapy (70 patients). The majority of cases of treatment discontinuation for safety reasons occurred during the first 2 years. In contrast, discontinuation due to ineffectiveness showed a more constant rate over the 7-year period. Mean DAS for patients still on treatment with infliximab decreased from 5.7 (standard error [SE] 0.1) at baseline to 3.0 (SE 0.1) at year 4 and remained that low until year 7 (3.0 [SE 0.1]). Low disease activity (defined as DAS28 <3.2) was present in 60.9% of patients, and 45.5% achieved remission (DAS28 <2.6). DAS28 at the time of treatment discontinuation due to ineffectiveness decreased over the 7-year period from 5.6 (SE 0.3) in 2001 to 4.8 (SE 0.3) in 2008.

Conclusions

This observational study revealed that patients who continue to receive infliximab experience sustained clinical benefit. The majority of safety issues occurred during the first 2 years of infliximab therapy. We observed that the DAS at the time of therapy discontinuation showed a trend to decrease over time.

Therapeutic agents for patients with rheumatoid arthritis and an inadequate response to tumour necrosis factor-alpha antagonists

BACKGROUND

Rheumatoid arthritis (RA) is a disabling autoimmune disease; unless adequately controlled, patients have a poor long-term prognosis. Tumour necrosis factor (TNF)-alpha antagonists have provided relief for many RA patients; however, despite their efficacy, some patients do not respond or fail to maintain initial response. In the UK, patients with an inadequate response to TNF-alpha antagonists have limited options, as the National Institute of Clinical Excellence (NICE) currently only recommend switching to an alternative TNF-alpha antagonists if discontinuation occurs due to safety during the first 6 months of treatment. The EU has approved three biological agents, rituximab, abatacept, and tocilizumab, for patients with RA with an inadequate response to TNF-alpha antagonists.

OBJECTIVE

This review examines the clinical experience with two therapies targeting key immune cells involved in RA -- rituximab (lyses B-cells), and abatacept (T-cell co-stimulation modulator) -- specifically focusing on patients with an inadequate response to TNF-alpha blockade.

METHODS

Phase II/III clinical trials and original studies were identified using Medline and Pubmed; articles assessing the efficacy and/or safety of rituximab or abatacept in patients with RA refractory to TNF-alpha blockade were reviewed.

CONCLUSIONS

Clinical data for rituximab and abatacept demonstrate that both reduce disease activity in TNF-alpha antagonist inadequate responders, suggesting that agents with alternative mechanisms of action, such as those targeting key immune cells, may be useful in this patient population.

Infliximab concentration monitoring improves the control of disease activity in rheumatoid arthritis

Introduction

Adjustment of infliximab dosage for individuals may be useful in improving therapeutic response in rheumatoid arthritis (RA). Herein, we aimed to determine whether measurement of infliximab serum concentration modifies the therapeutic decision and improves the control of disease activity.

Methods

RA patients routinely treated with infliximab were included in an observational open-label study. On visit 1 (V1), according to the disease activity, a preliminary therapeutic decision was selected among four therapeutic options and a blood sample was collected to measure trough serum infliximab concentration. The final therapeutic decision, based on both disease activity and serum infliximab concentration assessed at V1, was applied at the following infusion (V2). Clinical and biological evaluations were performed at V3 and V4 and compared with those at V1.

Results

We included 24 patients. The final therapeutic decision differed from the preliminary decision for 12 patients (50%). For patients with increased infliximab dosage at V2, mean disease activity score for 28 joints (DAS28) decreased by about 20% at V3 or V4 as compared with V1 (P < 0.05). Decreased DAS28 was correlated with increased serum infliximab concentration (P < 0.02).

Conclusions

The measurement of infliximab trough concentration modifies the therapeutic decision for RA patients and helps improve control of disease activity. Therapeutic drug monitoring of infliximab in RA may be useful for individual dosage adjustment.

Dose escalation of infliximab therapy in arthritis patients is related to diagnosis and concomitant methotrexate treatment: observational results from the South Swedish Arthritis Treatment Group register

OBJECTIVE

To study frequency of dose escalation in infliximab-treated patients and to identify possible predictors thereof.

METHODS

Patients with chronic arthritis initiating their first course of anti-TNF treatment with infliximab at Lund University Hospital were included in a structured clinical follow-up protocol. Information on diagnosis, drug dosage, disease duration, previous and ongoing DMARDs, treatment start and cessation were prospectively collected during the period March 1999 through February 2007. All patients were started on a dose of 3 mg/kg at time 0, week 2, week 6 and then every eighth week independent of diagnosis and were followed for a period of 2 yrs.

RESULTS

A total of 206 patients were included in the study. Thirty-two of the patients had PsA, 25 had AS and 149 patients had RA. A minor dose escalation, defined as less than doubling of the dosage, was observed for 53, 48 and 42% of the patients with PsA, AS and RA, respectively. The corresponding values for major dose escalation was observed for 19, 8 and 15% of the patients, respectively. Regression analysis showed that patients with a diagnosis of PsA (P = 0.03), longer follow-up period (P < 0.01), and lack of concomitant MTX treatment (P = 0.03) were significantly associated with risk of dose escalation.

CONCLUSION

Dose escalations were performed in 59% of all infliximab-treated patients during the first 2 yrs of treatment. Our data suggest that PsA patients might require higher dosages than RA and AS patients.

Efficacy and safety of etanercept 50 mg twice a week in patients with rheumatoid arthritis who had a suboptimal response to etanercept 50 mg once a week: results of a multicenter, randomized, double-blind, active drug-controlled study

OBJECTIVE

To evaluate the efficacy and safety of treatment with 50 mg of etanercept twice a week plus weekly methotrexate (MTX; > or =15 mg) in patients with rheumatoid arthritis (RA) who had a suboptimal response to 50 mg of etanercept once a week plus weekly MTX (> or =15 mg).

METHODS

In this multicenter, randomized, double-blind, active drug-controlled study, suboptimal responders to treatment with MTX plus etanercept 50 mg once weekly were given MTX plus etanercept 50 mg twice weekly (n = 160) or MTX plus etanercept 50 mg once weekly plus a placebo (n = 40) for 12 weeks. In a subsequent 12-week open-label period, patients who responded to etanercept 50 mg twice weekly decreased their dosage to 50 mg once weekly, those who had a partial response to etanercept 50 mg once weekly increased their dosage to 50 mg twice weekly, and those who had no response to etanercept 50 mg twice weekly were discontinued. The primary end point was the proportion of patients with a response on the Disease Activity Score 28-joint assessment (DAS28) at week 12.

RESULTS

A total of 201 patients were randomized; 187 completed 12 weeks, and 102 completed 24 weeks. At week 12 (double-blind period), the DAS28 response in the 50 mg twice weekly and the 50 mg once weekly groups was not significantly different (45.6% versus 35.0%; P = 0.285), and similar proportions of patients in the groups taking 100 mg and 50 mg experienced adverse events (34.4% versus 37.5%; P = 0.711). Serious adverse events occurred in 7 of 160 of the 50 mg twice weekly group and 0 of 40 of the 50 mg once weekly group (P = 0.387), and serious infectious events occurred in 3 of 160 patients in the 50 mg twice weekly group (P = 0.884).

CONCLUSION

Etanercept 50 mg once weekly is an optimal dosage in most patients with RA. Increasing the dosage from 50 mg once weekly to 50 mg twice weekly in suboptimal responders did not significantly improve their DAS28 responses.

Rheumatoid arthritis: strategies in the management of patients showing an inadequate response to TNFalpha antagonists

The introduction of medications that target specific proinflammatory cytokines has revolutionized the management of patients with rheumatoid arthritis. The agents that antagonize the effects of tumour necrosis factor (TNF)-alpha -- infliximab, etanercept and adalimumab -- have consistently shown very good efficacy for controlling the clinical and radiographic manifestations of the disease. However, it has become apparent that some patients will receive no clinical benefit, gradually lose the effect over time or experience adverse effects with the TNFalpha antagonists. The management of these patients is challenging and there are no clear guidelines. The concomitant administration of a disease-modifying antirheumatic drug, such as methotrexate, has been shown to improve outcomes. Optimization of the methotrexate or TNFalpha antagonist dose may lead to improved responses, as demonstrated in some dose escalation studies. Switching to another TNFalpha antagonist is a step that is supported by small, mostly uncontrolled studies. Finally, the T-cell co-stimulation antagonist abatacept, as well as the B-cell depleting agent rituximab, are also available for use in patients who have had an inadequate response or intolerance to the TNFalpha antagonists.Genotypic studies have identified TNF and TNF receptor polymorphisms that appear to predict independently whether a patient will respond to a TNFalpha antagonist, but genotyping is not available for routine use in clinical practice. Until such tools for predicting response are widely available, the management of patients with poor responses to TNFalpha antagonists will have to depend upon the wishes of the patient regarding medication dosage schedules and adverse effect profiles, as well as how comfortable the treating physician is with the available biological medications. In this article, we review the current data and construct an algorithm to help guide clinicians in the management of patients with inadequate responses to the TNFalpha antagonists.

Double-blinded infliximab dose escalation in patients with rheumatoid arthritis

OBJECTIVE

To determine the efficacy, safety and pharmacokinetics of infliximab dose escalation in patients with rheumatoid arthritis (RA) who had an inadequate response to 3 mg/kg infliximab treatment or whose disease flared after initially responding.

METHODS

Patients with active RA, despite receiving methotrexate, received infliximab 3 mg/kg at weeks 0, 2, 6 and 14 in one of the three arms of the START trial. Beginning at week 22, patients had their infliximab dose increased in a double-blind fashion in increments of 1.5 mg/kg if the total tender and swollen joint count did not improve by at least 20% from baseline (lack of response) or the improvement at week 22 or later worsened by 50% or more (criterion for flare).

RESULTS

Of the 329 evaluable patients, 100 (30.4%) patients required dose escalation at or after week 22 because of flare or lack of response. The majority of patients (>80%) who received up to three dose escalations showed >/=20% improvement in the total tender and swollen joint count after their last dose escalation. Patients who required dose escalations generally had lower preinfusion serum infliximab concentrations than those who did not require them. The incidences of adverse events and serious adverse events for the patients who received dose escalation(s) were similar to those of patients who did not receive dose escalation.

CONCLUSION

Fewer than one-third of patients required a dose escalation. The majority of patients showed improvement after receiving increased doses of infliximab, without an increased risk of adverse events.

Pooled indices to measure rheumatoid arthritis activity: a good reflection of the physician's mind?

Several pooled indices for the assessment of rheumatoid arthritis disease activity are available to rheumatologists. Face and criterion validity of these instruments can be assessed by determining the association of their measurements with opinions of physicians. Several confounding aspects must be considered in such analyses, especially blinding of the person(s) making the decisions to the instruments being studied and to the objective of the study in general. From several studies in the literature, there is currently no evidence that any one of the available composite indices is better or worse than any other. The choice of index in clinical practice should ideally be based on practical considerations related to the needs of the rheumatologist in the respective health care setting.

Four-year follow-up of infliximab therapy in rheumatoid arthritis patients with long-standing refractory disease: attrition and long-term evolution of disease activity

Although there is strong evidence supporting the short-term efficacy and safety of anti-tumour necrosis factor-alpha agents, few studies have examined the long-term effects. We evaluated 511 patients with long-standing refractory rheumatoid arthritis treated with intravenous infusions of infliximab 3 mg/kg at weeks 0, 2, 6, and 14 and every 8 weeks thereafter for 4 years. Among the initial 511 patients included in the study, 479 could be evaluated; of these, 295 (61.6%) were still receiving infliximab treatment at year 4 of follow-up. The most common reasons for treatment discontinuation were lack of efficacy (65 patients, 13.6%), safety (81 patients, 16.9%), and elective change (38 patients, 7.9%). Analysis of disease activity scores (DAS28 [disease activity score based on the 28-joint count]) over time showed that, after the initial rapid improvement during the first 6 to 22 weeks of therapy, a further decrease in disease activity of 0.2 units in the DAS28 score per year was observed. DAS28 scores, measured at week 14 or 22, were found to predict subsequent discontinuation due to lack of efficacy. In conclusion, long-term maintenance therapy with infliximab 3 mg/kg is effective in producing further reductions in disease activity. Disease activity measured by the DAS28 at week 14 or 22 of infliximab therapy was the best predictor of long-term attrition.

Dosisanpassung bei Patienten mit rheumatoider Arthritis unter Therapie mit Infliximab in der rheumatologischen Versorgung in Deutschland

OBJECTIVE

Data from international observational studies show that a considerable proportion of patients use higher dosages of infliximab (INF) than the usual 3 mg every 8 weeks used in Germany for treatment of rheumatoid arthritis. The Data are, however, inconsistent and vary between countries. Using data from the German Biologics Register RABBIT we investigated: (1) how dosage of INF develops during the first year of treatment in routine care, and (2) how dosage translates into clinical effectiveness.

PATIENTS

We analysed data from 344 patients who started a treatment with INF at their inclusion into the register and who were observed for the subsequent 12 months. Mean dosage at 3 months (after the loading dose) was 3.2 mg/kg body weight/infusion and 3.3 mg/kg after 1 year. If we also consider shortening the infusion intervals, the mean dosages at the start and after 1 year were 4.0 mg/kg body weight every 8 weeks.

RESULTS

Patients who were treated with low dosages of up to 3 mg/kg/8 weeks showed significantly less improvement (EULAR response) than those who were treated with higher dosages.

CONCLUSIONS

The data show that German rheumatologists are aware of the high costs of treatment and try to use the lowest possible dosage. However, for a certain proportion of the patients this might be insufficient.

Recommendations of the French Society for Rheumatology. TNFalpha antagonist therapy in rheumatoid arthritis

OBJECTIVES

To develop recommendations for TNFalpha-antagonist therapy in patients with rheumatoid arthritis (RA) seen in everyday practice, under the aegis of the French Society for Rheumatology.

METHOD

We used the methods recommended by the French Agency for Healthcare Accreditation and Evaluation, the AGREE collaboration, and the European League against Rheumatism (EULAR). The recommendations focus on patient selection, monitoring, and treatment adjustments.

RESULTS

Criteria for selecting patients eligible for TNFalpha-antagonist treatment of RA include: 1) a definitive diagnosis of RA; 2) disease activity for longer than 1 month, including presence of objective signs of inflammation; or radiographic progression; 3) previous failure of methotrexate in the highest tolerated dosage or of another disease-modifying antirheumatic drug in patients with contraindications to methotrexate; 4) absence of contraindications to TNFalpha-antagonist therapy. When starting TNFalpha-antagonist therapy 1) a thorough baseline evaluation should be conducted; 2) any of the three available agents can be used, as no differences in efficacy have been identified in patient populations; 3) concomitant methotrexate therapy is recommended regardless of the TNFalpha antagonist used; and 4) patients should receive standardized follow-up at regular intervals. Treatment adjustments should be based on the following: 1) the treatment objective is achievement of a EULAR response; 2) when such a response is not achieved, the dosage or dosing interval can be changed, or the patient can be switched to another TNFalpha antagonist; 3) in patients who experience intolerance to a TNFalpha antagonist, another TNFalpha antagonist may be tried, depending on the nature of the adverse event; 4) occurrence of a remission should lead to a reduction in symptomatic medications, most notably glucocorticoids where used; in the event of a prolonged remission, either the TNFalpha antagonist or the concomitant disease-modifying antirheumatic drug may be reduced.

CONCLUSION

These recommendations are intended to help physicians use TNFalpha antagonists in their everyday practice with RA patients. They do not constitute regulations.

DAS28: a useful instrument to monitor infliximab treatment in patients with rheumatoid arthritis

The Disease Activity Score using 28 joint counts (DAS28) has been developed in a cohort of patients with rheumatoid arthritis in which only conventional anti-rheumatic treatments were used. It has extensively been validated to monitor disease activity in daily clinical practice as well as in clinical trials. The study of Vander Cruyssen and colleagues showed that the DAS28 correlated best with the decisions of rheumatologists to increase the infliximab dose because of insufficient response. This result once more confirms the validity of the DAS28 to monitor disease activity in patients with rheumatoid arthritis and to titrate treatment with biologicals.

DAS28 best reflects the physician's clinical judgment of response to infliximab therapy in rheumatoid arthritis patients: validation of the DAS28 score in patients under infliximab treatment

This study is based on an expanded access program in which 511 patients suffering from active refractory rheumatoid arthritis (RA) were treated with intravenous infusions of infliximab (3 mg/kg+methotrexate (MTX)) at weeks 0, 2, 6 and every 8 weeks thereafter. At week 22, 474 patients were still in follow-up, of whom 102 (21.5%), who were not optimally responding to treatment, received a dose increase from week 30 onward. We aimed to build a model to discriminate the decision to give a dose increase. This decision was based on the treating rheumatologist's clinical judgment and therefore can be considered as a clinical measure of insufficient response. Different single and composite measures at weeks 0, 6, 14 and 22, and their differences over time were taken into account for the model building. Ranking of the continuous variables based on areas under the curve of receiver-operating characteristic (ROC) curve analysis, displayed the momentary DAS28 (Disease Activity Score including a 28-joint count) as the most important discriminating variable. Subsequently, we proved that the response scores and the changes over time were less important than the momentary evaluations to discriminate the physician's decision. The final model we thus obtained was a model with only slightly better discriminative characteristics than the DAS28. Finally, we fitted a discriminant function using the single variables of the DAS28. This displayed similar scores and coefficients as the DAS28. In conclusion, we evaluated different variables and models to discriminate the treating rheumatologist's decision to increase the dose of infliximab (+MTX), which indicates an insufficient response to infliximab at 3 mg/kg in patients with RA. We proved that the momentary DAS28 score correlates best with this decision and demonstrated the robustness of the score and the coefficients of the DAS28 in a cohort of RA patients under infliximab therapy.