Infliximab dosage and infusion frequency in clinical practice: experiences in the Stockholm biologics registry STURE

Infliximab dose adjustment can improve the clinical and radiographic outcomes of rheumatoid arthritis patients: REVIVE study results

Purpose

We evaluated the clinical responses and radiographic outcomes of 90 patients with rheumatoid arthritis (RA) undergoing continuous or dose-adjusted infliximab treatment over 104 weeks.

Patients and methods

Patients received 3 mg/kg infliximab continuously (the contin group; n=50), or the dose escalation and de-escalation of infliximab (3, 6, and 10 mg/kg) from week 14 (the adjusted group; n=40) based on the patient’s Disease Activity Score in 28 joints (DAS28). The retention rate, clinical response, and radiographic assessment were determined at week 104.

Results

The contin and adjusted groups’ retention rates at week 104 were 56.8 and 66.7%, and the groups’ low disease activity in the DAS28 was 39.1 and 66.7%, respectively. Remission based on the DAS28 and the American College of Rheumatology (ACR)/European League against Rheumatism (EULAR) Boolean-based criteria was significantly increased in the adjusted group. In the radiographic assessment, there was also a significant reduction in the mean changes in total Sharp score. The cumulative rates of any adverse effects showed no significant difference between the groups.

Conclusion

In an assessment of adequate DAS28 results, the RA patients who did not respond to the initial dose of infliximab showed improved clinical responses and radiographic assessment after a dose adjustment of infliximab, without an increased risk of serious adverse events.

Immunogenicity of biologic agents in rheumatoid arthritis patients: lessons for clinical practice

Anti-drug antibodies (ADAbs) develop in up to a third of patients treated with biologic agents, with such immunogenicity being one of the main reasons for the loss of efficacy observed in an important proportion of patients treated with such agents. The appearance of ADAbs has consequences in terms of efficacy and tolerance of the biodrug: the development of ADAbs is associated with a poorer clinical response and with an increased risk of adverse effects. Formation of ADAbs has been observed with all biologic DMARDs, but anti-TNF agent mAbs appear to be the largest contributors, independent of humanization of the antibody. ADAb identification is technically difficult and not standardized, partly explaining important variations between published studies. A variety of factors can influence the risk of ADAb appearance, some of which are linked to the treatment strategy, such as the combination with synthetic DMARDs or the rhythm of administration of the biodrug, whereas other factors are dependent on the patient, such as the level of inflammation at onset or body weight. The detection of these antibodies and/or the dosage of the biologic agent itself could have consequences for the bedside practice of clinicians and should be well understood. This review of the literature proposes an overview of the data published on the subject to help clinicians manage the biodrugs according to these new concepts.

Two dosing regimens of certolizumab pegol in patients with active rheumatoid arthritis

Objective

To investigate clinical efficacy and safety of 2 certolizumab pegol (CZP) maintenance dosing regimens plus methotrexate (MTX) in active rheumatoid arthritis (RA) patients achieving the American College of Rheumatology 20% improvement criteria (ACR20) after the CZP 200 mg every 2 weeks open-label run-in period.

Methods

DOSEFLEX (dosing flexibility) was a double-blind, placebo-controlled randomized study with an open-label run-in phase. During the run-in phase, all patients received CZP 400 mg (weeks 0, 2, and 4) and 200 mg every 2 weeks to week 16. Week 16 ACR20 responders were randomized 1:1:1 at week 18 to CZP 200 mg every 2 weeks, 400 mg every 4 weeks, or placebo.

Results

A total of 209 (of 333) patients were randomized at week 18 (CZP: 200 mg, n = 70; 400 mg, n = 70; placebo, n = 69). Groups had similar baseline characteristics (week 0). Week 34 ACR20 response rates were comparable between the CZP 200 mg every 2 weeks and the 400 mg every 4 weeks groups (67.1% versus 65.2%), which was significantly higher than placebo (44.9%; P = 0.009 and P = 0.017). ACR50/70 and remission criteria were met more frequently in CZP groups than placebo at week 34, with similar responses between anti–tumor necrosis factor–experienced and naive patients. Improvements from baseline Disease Activity Score in 28 joints using the erythrocyte sedimentation rate and Health Assessment Questionnaire disability index scores were maintained in CZP groups from week 16 to 34 while worsening on placebo. Adverse event (AE) rates in the double-blind phase were 62.9% versus 60.9% versus 62.3%; serious AE rates were 7.1% versus 2.9% versus 0.0% (CZP 200 mg, 400 mg, and placebo groups).

Conclusion

In active RA patients with an incomplete MTX response, CZP 200 mg every 2 weeks and 400 mg every 4 weeks were comparable and better than placebo for maintaining clinical response to week 4 following a 16-week, open-label run-in phase.

Infliximab efficacy in rheumatoid arthritis after an inadequate response to etanercept or adalimumab: results of a target-driven active switch study

OBJECTIVE

Evaluate efficacy of infliximab with response-driven dosing in patients with active RA.

RESEARCH DESIGN AND METHODS

Patients (n = 203) with active RA despite methotrexate + etanercept/adalimumab, participated in this active-infliximab-switch study. Infliximab 3 mg/kg was infused at Weeks 0, 2, 6, 14, and 22 with escalation to 5 or 7 mg/kg depending on EULAR response at Weeks 14 and 22. The primary endpoint was EULAR response at Week 10. Safety was assessed through Week 30. Infliximab levels and antibodies to infliximab (ATI) were measured at Weeks 0, 6, 14, and 26.

CLINICAL TRIAL REGISTRATION

NCT 00714493, EudraCT 2007-003288-36.

RESULTS

Of 197 evaluable patients, 120/77 previously received etanercept/adalimumab. Baseline mean (SD) swollen and tender joint counts were 17.3 (10.54) and 30.2 (16.89), respectively; mean DAS28-ESR was 6.19 (0.981). At Week 10, 98 (49.7%; 95% CI: 42.6%, 56.9%) patients achieved EULAR response, with a significantly improved DAS28-ESR score (mean [SD] change -1.1 [1.15]; p < 0.001). EULAR response was achieved by 41.7%/62.3% of patients previously receiving etanercept/adalimumab (p = 0.006). At Week 26, 51.8% (95% CI: 44.6%, 58.9%) of patients achieved or maintained EULAR response. Infliximab dose was escalated in 100 patients, 52% of whom achieved EULAR response at Week 26. Median serum concentration levels at Week 26 showed that dose escalation helped EULAR non-responders achieve levels similar to or higher than the levels seen in responders. ATI were associated with lower serum concentrations of infliximab, consistent with lower efficacy rates among ATI-positive patients.

CONCLUSION

Infliximab, in treat-to-target settings with individual dose escalation, demonstrated significant efficacy at Weeks 10 and 26 in patients switched to infliximab after inadequate response to etanercept/adalimumab. The observed efficacy indicated that the switch to infliximab and ability to increase dose in a targeted fashion were beneficial.

KEY LIMITATIONS

Given the relatively short duration of study follow-up, these safety findings require confirmation in a longer-term study.

Impact of different infliximab dose regimens on treatment response and drug survival in 462 patients with psoriatic arthritis: results from the nationwide registries DANBIO and ICEBIO

OBJECTIVE

The aim of this study was to describe dose regimens, dose escalation and clinical outcomes in TNF-α inhibitor (TNFi)-naive patients with PsA treated with infliximab in routine rheumatology care.

METHODS

We conducted an observational cohort study based on the nationwide Danish Rheumatologic Database (DANBIO) and Center for Rheumatology Research (ICEBIO) registries. Stratified by country, characteristics of patients treated with ≤3 mg infliximab/kg body weight, 3-5 mg/kg or ≥5 mg/kg every 8 weeks were described. Outcomes were evaluated by ACR 20%, 50% and 70% (ACR20/50/70) responses and European League Against Rheumatism good response after 6 months, disease activity after 12 months, Kaplan-Meier plots and regression analyses.

RESULTS

Four hundred and sixty-two patients (376 Danish, 86 Icelandic) received treatment with infliximab. In Danish patients, the starting dose was ≤3 mg/kg in 110 patients (29%), 3-5 mg/kg in 157 (42%), ≥5 mg/kg in 38 (10%) and unregistered in 71 (19%). In Icelandic patients, corresponding numbers were 64 (74%), 17 (27%), 0 (0%) and 5 (6%). Patients with a higher body weight received lower doses per kilogram. Danish patients received higher doses than Icelandic patients at baseline [median 3.1 (interquartile range 3.0-3.8) vs 2.3 (2.1-2.9) mg/kg, P < 0.05] and after 12 months [3.3 (3.0-4.5) vs 2.9 (2.2-3.5) mg/kg, P < 0.0001]. After 12 months, 58% of Danish and 66% of Icelandic patients maintained treatment. Danish patients had shorter drug survival than Icelandic patients (1183 vs 483 days). In univariate analyses stratified by country, time until dose escalation, response rates, drug survival and 1-year's disease activity were independent of starting dose. Drug survival was shorter among patients not receiving concomitant MTX.

CONCLUSION

In clinical practice, > 70% of Icelandic and Danish PsA patients treated with infliximab received sustained doses below the 5 mg/kg every 8 weeks recommended in international guidelines. Lower starting doses did not affect drug survival or response.

Long-term durability and dose escalation patterns in infliximab therapy for psoriasis

BACKGROUND

Infliximab often requires dose escalation to maintain response. Studies regarding long-term durability and dose escalation patterns for psoriasis are few.

OBJECTIVE

We sought to evaluate dose escalation patterns in psoriatic patients to identify factors of lack of optimal response to infliximab.

METHODS

A retrospective cohort study included 93 patients (216.3 patient-years) treated with infliximab for psoriasis. Kaplan-Meier analysis assessed drug durability.

RESULTS

A median infliximab dose of 5.42 mg/kg/mo (range: 2.71-10.83) for a mean of 28 months was administered. Two thirds of patients received a dose escalation. Concurrent methotrexate extended duration of therapy (by a mean ± SD of 19.5 ± 8.1 months, P = .034), including time until first dose escalation (by a mean ± SD of 12.0 ± 6.1 months, P = .037), and failure (by a mean ± SD of 20.7 ± 6.7 months, P = .034). Patients who increased the infusion frequency before increasing the dose remained on infliximab 8.4 months longer than those who first increased the dose (P = .045). Four patients experienced adverse events; 2 required discontinuation.

LIMITATIONS

Psoriasis Area and Severity Index, infliximab levels, and antibody titers were not measured.

CONCLUSIONS

Dose escalation optimizes durability of infliximab. The probability of maintaining response is enhanced by concomitant methotrexate and increasing the infusion frequency before increasing the dose.

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.

Tumor necrosis factor blocker dose escalation among biologic naïve rheumatoid arthritis patients in commercial managed-care plans in the 2 years following therapy initiation

OBJECTIVE

This study uses real-world US managed-care claims data to estimate dose escalation rates over the first and second years of therapy among biologic naïve rheumatoid arthritis (RA) patients initiating tumor necrosis factor (TNF) blocker therapy with etanercept, adalimumab, or infliximab.

METHODS

Non-elderly adult (age 18-65 years) RA patients initiating etanercept, adalimumab, or infliximab from July 1, 2005 to April 30, 2009, were identified using the MarketScan Commercial Database. National and regional dose-escalation patterns were evaluated 12 and 24 months after initiation. In the single-instance method, dose escalation was defined as having one average weekly dose 115%, 130%, or 150% greater than the initial average weekly dose. By the two-instances method, dose escalation was defined as having two consecutive claims with an average weekly dose 115% or 130% greater than the initial average weekly dose.

RESULTS

A total of 2747 patients met the inclusion criteria (mean age 50 years [SD=10]; 74% female). More patients initiated etanercept (44%) than adalimumab (37%) or infliximab (20%). Using the single-instance method, dose escalation at 12 months ranges were 0.8-1.5% for etanercept, 10.8-12.5% for adalimumab, and 16.4-42.5% for infliximab; ranges at 24 months were 0.8-2.1% for etanercept, 14.3-17.5% for adalimumab, and 26.4-57.6% for infliximab. The two-instances method showed a similar relationship among the treatment cohorts at both 12 and 24 months, with lower dose-escalation rates for etanercept (0.8%, 0.8%) than adalimumab (8.7%, 13.3%) or infliximab (22.9%, 37.6%) at the 130% threshold (p<0.001). Dose-escalation rates for etanercept, adalimumab, and infliximab were consistent across US geographic regions.

CONCLUSION

Patients initiating etanercept had lower rates of dose escalation than patients initiating adalimumab or infliximab in the first and second year following therapy initiation, as well as across US geographic regions. These results may not be generalizable to the entire US RA population.

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.

Therapeutic hotline: Re-induction may be useful to manage psoriasis relapse during long-term maintenance treatment with infliximab: a retrospective analysis

Infliximab is an anti-tumor necrosis factor-alpha monoclonal antibody that is highly effective for the treatment of psoriatic disease. During maintenance treatment, some patients may experience a disease relapse, and, in such circumstances, dose intensification is frequently used to regain efficacy. We report our cumulative experience on the use of infliximab re-induction in patients whose psoriasis relapsed during long-term maintenance treatment with infliximab. From September 2005 to January 2009, 22 patients required re-induction because of a relapse of their psoriasis. Re-induction was effective in restoring response in most patients and was well tolerated in all cases, without occurrence of serious or unexpected adverse events.

Infliximab treatment in patients with rheumatoid arthritis and spondyloarthropathies in one rheumatological center: two years' drug survival

The aim of the present study was to determine the drug survival during 2 years' follow-up in patients (n = 104) with active rheumatoid arthritis (RA) or spondyloarthropathy (SpA) who were treated with infliximab as their first biological anti-rheumatic drug in a single rheumatological center. According to the national guidelines, infliximab was added to the treatment with combinations of traditional disease-modifying anti-rheumatic drugs (DMARD). Patients' records were analyzed at baseline and after 2 years of follow-up. The response to treatment was determined inadequate if the response was lower than ACR50 (American College of Rheumatology 50) in RA or the reduction of Bath Ankylosing Spondylitis Disease Activity Index (BASDAI) was lower than 50% or 2 cm in SpA. Drug survival in infliximab-treated patients after 2 years was 40%, and among those who continued with the therapy the prednisolone dose has been reduced by 52%. Discontinuation rate was 60% during 2 years of follow-up, where 7% achieved remission and 22% of the patients were regarded as poor responders. As much as 24% of the patients discontinued due to an adverse event, mainly infections and hypersensitivity reactions. Two drug-related leukopenias were diagnosed. In the present study, infliximab therapy was initiated in RA or SpA patients who had active disease despite ongoing treatment with combinations of DMARDs. The drug survival with infliximab was 40% after 2 years of follow-up. During the 2-year follow-up, 60% discontinued infliximab treatment, mainly due to unsatisfactory or waning efficacy or a severe adverse event.

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.