Clinical relevance of monitoring serum adalimumab levels in axial spondyloarthritis

Adalimumab Drug Monitoring and Treatment Adjustment to Drug Antibodies in Noninfectious Uveitis

PURPOSE

To explore the incidence of antibodies against adalimumab (AAA) development in noninfectious uveitis (NIU) and to examine the impact of treatment adjustment in nonresponders.

DESIGN

Retrospective case series.

METHODS

In this single-center study of patients with NIU treated with adalimumab, blood samples for adalimumab and AAA were collected and therapeutic adjustments post-monitoring in non-responders were analyzed including changes in injection intervals, addition of conventional disease-modifying antirheumatic drugs (cDMARD), and treatment alterations to biologic DMARD. The main outcome measures were the proportion of patients with positive AAA and active uveitis, decrease of AAA at final follow-up by different therapeutic interventions.

RESULTS

Of 42 patients who underwent laboratory investigations at 17.9 months after adalimumab initiation, 22 (52.4%) patients who were nonresponders demonstrated AAA (1243 ng/mL) with a mean adalimumab trough level of 3.0 µg/mL, significantly lower than the mean drug levels of patients without AAA (11.8 µg/mL). Fifteen (35.7%) patients were receiving concurrent treatment with a second immunosuppressive agent, but the mean antibody level and the mean adalimumab level were not statistically significantly different from the monotherapy group (P = .13 and P = .34). Reduction in AAA levels and relapse management was greatest among nonresponders who were treated by increasing the adalimumab dose and adding an additional immunosuppressive drug (-3565 ng/mL), followed by patients who were shifted to a different biologic (-1153 ug/mL).

CONCLUSIONS

The presence of AAA was detected in 88% of nonresponder patients and was associated with undetectable adalimumab drug levels. This underscores immunogenicity as a major cause of loss of response in uveitis patients receiving biotherapies. Increasing the dose of adalimumab injections together with the addition of low-dose cDMARDs was the most effective adjustment in immunized nonresponders for whom the adalimumab drug concentration was low.

Adalimumab serum levels and anti-drug antibodies: associations to treatment response and drug survival in inflammatory joint diseases

OBJECTIVES

To explore associations between serum adalimumab level, treatment response and drug survival in order to identify optimal drug levels for therapeutic drug monitoring of adalimumab. Also, to assess the occurrence and risk factors of anti-drug antibody (ADAb) formation.

METHODS

Non-trough adalimumab and ADAb levels were measured by automated fluorescence assays in serum collected after 3 months of adalimumab treatment in patients with RA, PsA or axial SpA (axSpA) included in the observational NOR-DMARD study. Treatment response was evaluated after 3 months and drug survival was evaluated during long-term follow-up.

RESULTS

In 340 patients (97 RA, 69 PsA, 174 axSpA), the median adalimumab level was 7.3 mg/l (interquartile range 4.0-10.3). A total of 33 (10%) patients developed ADAbs. Findings were comparable across diagnoses. In RA and PsA, adalimumab levels ≥6.0 mg/l were associated with treatment response [odds ratio (OR) 2.2 (95% CI 1.0, 4.4)] and improved drug survival [hazard ratio 0.49 (95% CI 0.27, 0.80)]. In axSpA, a therapeutic level could not be identified, but higher adalimumab levels were associated with response. Factors associated with ADAb formation were previous bDMARD use, no methotrexate comedication and the use of adalimumab originator compared with GP2017.

CONCLUSION

Higher adalimumab levels were associated with a better response and improved drug survival for all diagnoses, with a suggested lower threshold of 6.0 mg/l for RA/PsA. This finding, the large variability in drug levels among patients receiving standard adalimumab dose and the high proportion of patients developing ADAbs encourages further investigations into the potential role of therapeutic drug monitoring of adalimumab.

No Correlation between Anti-drug Antibodies and Therapeutic Response in Tunisian Patients with Chronic Inflammatory Diseases Treated by TNF Blockers

INTRODUCTION

Tumor necrosis factor alpha (TNF alpha) blockers such as infliximab (IFX) and adalimumab (ADA) had significantly changed the course of inflammatory diseases such as rheumatoid arthritis (RA), spondyloarthritis (SpA) and Crohn's disease (CD). However, about 30% of patients do not respond to these treatments. This lack of response may be due to the formation of antibodies against these drugs (anti-drug antibodies: ADAbs). The aim of this study was to determine the prevalence of ADAbs against IFX and ADA, and the trough serum concentration of IFX and ADA in RA, SpA or CD patients and to assess their impact on the therapeutic response.

METHODS

A cross sectional, multi-centric study was conducted, including patients with RA, SpA or CD treated with IFX or ADA as a first biotherapy for at least 6 months. ADAbs and trough levels were measured by an Enzyme Linked Immunosorbent assay (ELISA).

RESULTS

197 patients were included (57 RA, 73 SpA and 67 CD). ADAbs were positive in 40% of cases for IFX and 25% for ADA. They were positive in 40% of SpA, 35% of RA, and 21% of CD. The presence of ADAbs was inversely correlated to the trough levels of IFX and ADA during RA (p = 0.01 and p < 0.0001), SpA (p < 0.01 and p < 0.0001) and CD (p = 0.001 and p = 0.04). For all pathologies, the presence of ADAbs was not correlated with disease activity. Concomitant methotrexate significantly reduced immunogenicity.

CONCLUSION

In our study, the presence of ADAb and low trough levels seem to not affect the therapeutic response in patients on TNF alpha antagonists. Other tracks more than immunogenicity should be investigated to explain the loss of response to these biotherapies.

EULAR points to consider for therapeutic drug monitoring of biopharmaceuticals in inflammatory rheumatic and musculoskeletal diseases

OBJECTIVE

To develop EULAR points-to-consider for therapeutic drug monitoring (TDM) of biopharmaceuticals in inflammatory rheumatic and musculoskeletal diseases (RMDs).

METHODS

The points-to-consider were developed in accordance with EULAR standardised operation procedures by a multidisciplinary task force from eight European countries, based on a systematic literature review and expert consensus. Level of evidence and strength of the points-to-consider were determined, and mean levels of agreement among the task force were calculated using a 10-point rating scale.

RESULTS

Six overarching principles and 13 points-to-consider were formulated. The level of agreement among the task force for the overarching principles and points-to-consider ranged from 8.4 to 9.9.The overarching principles define TDM and its subtypes, and reinforce the underlying pharmacokinetic/pharmacodynamic principles, which are relevant to all biopharmaceutical classes. The points-to-consider highlight the clinical utility of the measurement and interpretation of biopharmaceutical blood concentrations and antidrug antibodies in specific clinical scenarios, including factors that influence these parameters. In general, proactive use of TDM is not recommended but reactive TDM could be considered in certain clinical situations. An important factor limiting wider adoption of TDM is the lack of both high quality trials addressing effectiveness and safety of TDM and robust economic evaluation in patients with RMDs. Future research should focus on providing this evidence, as well as on further understanding of pharmacokinetic and pharmacodynamic characteristics of biopharmaceuticals.

CONCLUSION

These points-to-consider are evidence-based and consensus-based statements for the use of TDM of biopharmaceuticals in inflammatory RMDs, addressing the clinical utility of TDM.

Immunogenicity of subcutaneous TNF inhibitors and its clinical significance in real-life setting in patients with spondyloarthritis

KEY MESSAGES

Considerable proportion of patients with SpA have been immunized to the subcutaneous anti-TNF drug they are using. Concomitant use of MTX protects from immunization, whereas SASP does not. Patients with SpA using subcutaneous anti-TNF drugs can benefit from monitoring of the drug trough levels. Immunization to biological drugs can lead to decreased efficacy and increased risk of adverse effects. The objective of this cross-sectional study was to assess the extent and significance of immunization to subcutaneous tumor necrosis factor (TNF) inhibitors in axial spondyloarthritis (axSpA) patients in real-life setting. A serum sample was taken 1-2 days before the next drug injection. Drug trough concentrations, anti-drug antibodies (ADAb) and TNF-blocking capacity were measured in 273 patients with axSpA using subcutaneous anti-TNF drugs. The clinical activity of SpA was assessed using the Bath AS Disease Activity Index (BASDAI) and the Maastricht AS Entheses Score (MASES). ADAb were found in 11% of the 273 patients: in 21/99 (21%) of patients who used adalimumab, in 0/83 (0%) of those who used etanercept, in 2/79 (3%) of those who used golimumab and in 6/12 (50%) of those who used certolizumab pegol. Use of methotrexate reduced the risk of formation of ADAb, whereas sulfasalazine did not. Presence of ADAb resulted in decreased drug concentration and reduced TNF-blocking capacity. However, low levels of ADAb had no effect on TNF-blocking capacity and did not correlate with disease activity. The drug trough levels were below the consensus target level in 36% of the patients. High BMI correlated with low drug trough concentration. Patients with low drug trough levels had higher disease activity. The presence of anti-drug antibodies was associated with reduced drug trough levels, and the patients with low drug trough levels had higher disease activity. The drug trough levels were below target level in significant proportion of patients and, thus, measuring the drug concentration and ADAb could help to optimize the treatment in SpA patients.

Therapeutic drug monitoring of biopharmaceuticals in inflammatory rheumatic and musculoskeletal disease: a systematic literature review informing EULAR points to consider

The objectives of this review were to collect and summarise evidence on therapeutic drug monitoring (TDM) of biopharmaceuticals in inflammatory rheumatic and musculoskeletal diseases and to inform the EULAR Task Force for the formulation of evidence-based points to consider. A systematic literature review (SLR) was performed, covering technical aspects and (clinical) utility of TDM, to answer 13 research questions. MEDLINE, Embase and Cochrane were searched until July 2020. American College of Rheumatology and EULAR abstracts were also considered for inclusion. Data were extracted in evidence tables and risk of bias assessment was performed. For the search on technical aspects, 678 records were identified, of which 22 papers were selected. For the clinical utility search, 3846 records were identified, of which 108 papers were included. Patient-related factors associated with biopharmaceutical blood concentrations included body weight, methotrexate comedication and disease activity. The identification of a target range was hampered by study variability, mainly disease activity measures and study type. Evidence was inconsistent for multiple clinical situations in which TDM is currently applied. However, for some particular scenarios, including prediction of future treatment response, non-response to treatment, tapering and hypersensitivity reactions, robust evidence was found. There is currently no evidence for routine use of proactive TDM, in part because published cost-effectiveness analyses do not incorporate the current landscape of biopharmaceutical costs and usage. This SLR yields evidence in favour of TDM of biopharmaceuticals in some clinical scenarios, but evidence is insufficient to support implementation of routine use of TDM.

Therapeutic drug monitoring of biologics in inflammatory bowel disease: unmet needs and future perspectives

Therapeutic drug monitoring (TDM) has emerged as a useful tool for optimising the use of biologics, and in particular anti-tumour necrosis factor (anti-TNF) therapy, in inflammatory bowel disease (IBD). However, challenges remain and are hindering the widespread implementation of TDM in clinical practice. These barriers include identification of the optimal drug concentration to target, the lag time between sampling and results, and the proper interpretation of anti-drug antibody titres among different assays. Solutions to overcome these barriers include the harmonisation of TDM assays and the use of point-of-care testing. Other unmet needs include well designed prospective studies and randomised controlled trials focusing on proactive TDM, particularly during induction therapy. Future studies should also investigate the utility of TDM for biologics other than anti-TNF therapies in both IBD and other immune-mediated inflammatory diseases such as rheumatoid arthritis and psoriasis, and the use of pharmacokinetic modelling dashboards and pharmacogenetics towards individual personalised medicine.

Therapeutic drug monitoring guides the management of patients with chronic non-infectious uveitis treated with adalimumab: a retrospective study

AIM

To assess the relevance of therapeutic drug monitoring (TDM) of adalimumab (ADA) treatment for the control of intraocular inflammation and treatment adjustment in chronic non-infectious uveitis (CNIU).

METHODS

Retrospective study of CNIU patients treated with ADA and for whom at least one dosage of serum ADA level and an antibodies against ADA (AAA) serology were performed, between June 2003 and July 2019.

RESULTS

A total of 44 ADA-treated patients benefited from a TDM. A total of 48/79 (61%) TDM were performed in responders, 11/79 (14%) in primary non-responders, and 20/79 (25%) in secondary non-responders. Responders had significantly higher ADA levels than non-responders (p=0.0004). AAA were detectable in six patients, they were primary non-responders (n=2), secondary non-responders (n=3) or responders (n=1). In the five non-responders and immunised patients, ADA was switched (to golimumab or methotrexate). Among non-responders, TDM led to an increased frequency of injections 12/31 (38%), increased dose 1/31 (3%) and switch of treatment 10/31 (32%) (one missing data). No modification of biotherapy was performed 7/31 (22%) and only local or oral corticotherapy was adjusted. In 24/31 cases of therapeutic adjustment in non-responders, an improvement was observed in 87% of cases. Among responders for whom the ADA level was above the efficacy threshold, the frequency of injections was decreased for 15/31 (48.4%) cases and no relapse was observed in 12/15 (80%) cases.

CONCLUSION

TDM of ADA treatment proved relevant to provide CNIU patients with a personalised and optimised treatment course (in terms of frequency and type of drug).

Immunogenicity of antitumor necrosis factor therapy in patients with spondyloarthritis

Objectives To evaluate the serum dosage of the biomedicine (DBM) and the incidence of antidrug antibody (ADA) against antitumor necrosis factor (TNF) in spondyloarthritis, and to demonstrate the influence of these parameters on the clinical efficiency. Methods We conducted a cross-sectional multicentric study including patients with spondylarthritis (SpA) under antiTNF (infliximab [INF], etanercept [ETA] and adalimumab [ADL]) for at least 6 months. A dosage of the ADA and DBM were practiced by the immuno-enzymatic essay. Result Seventy one patients were recruited. Disease modifying antirheumatic drugs (DMARDs) were associated with anti-TNF in 30%. ADA was positive in 54% for INF, 33% for ADL and 0% for ETA with a significant difference(p<0.0001). Immunogenicity was correlated to a bad therapeutic response (Bath Ankylosing Spondylitis Disease Activity Index [BASDAI]≥4)(p=0.04). The DBM was inversely correlated with the rate of ADA for patients treated with INF(p<0.0001) and ADL(p<0.0001). The DBM was also inversely correlated with BASDAI of INF(p=0.03) and ADL (p=0.01). ADA was significantly associated with an anterior switch of anti TNF(p=0.04), the use of INF(p=0.002), presence of coxitis(p=0.01) and higher body mass index (BMI)(p=0.007). DMARDs associated with anti TNF were not a protective factor for positive ADA. In a multivariate study, only INF and BMI were independent factors of positive ADA. Conclusion The ADA formation lowered the DBM and favored the therapeutic failure.

Residual Disease Burden in Patients With Axial Spondyloarthritis and Psoriatic Arthritis Despite Low Disease Activity States in a Multiethnic Asian Population

Objectives

To evaluate the burden of residual disease in patients with axial spondyloarthritis (axSpA) or psoriatic arthritis (PsA) who achieved low disease activity (LDA) status.

Methods

We used baseline data from a clinic registry of SpA in a tertiary hospital in Singapore. For axSpA, LDA was defined as Ankylosing Spondylitis (AS) Disease Activity Score based on erythrocyte sedimentation rate (ASDAS-ESR) < 2.1 or Bath AS Disease Activity Index (BASDAI) < 3/10. For PsA, LDA was defined by achieving 5/7 cutoffs in the minimal disease activity (MDA) or Clinical Disease Activity Index for Psoriatic Arthritis (cDAPSA) ≤ 13.

Results

In 262 cases of axSpA (21% women; mean ± standard deviation (SD) age 42 ± 14 yrs), 33% and 43% of patients achieved ASDAS-ESR and BASDAI LDA states, respectively, while in 142 cases of PsA (49% women, mean age 51 ± SD 14 yrs), 35% and 63% achieved MDA and cDAPSA LDA, respectively. Both axSpA and PsA patients with LDA had pain scores ranging from 14.0 to 21.4/100 and fatigue scores ranging from 3.1 to 3.6/10. Substantial burden in physical disability and mental well-being were observed, with low physical and mental component summary scores on the 36-item Short Form Health Survey. AxSpa patients in BASDAI LDA had higher ESR and lower disability than those in ASDAS-ESR LDA. cDAPSA classified nearly twice as many PsA patients into LDA than MDA. Compared to PsA patients in MDA LDA, those in cDAPSA LDA had higher active joint counts, dactylitis, enthesitis, pain scores, and patient global assessment.

Conclusion

Despite being in LDA, patients with axSpA and PsA experienced substantial residual burden in pain, poorer physical function, and mental well-being.

Head-to-Head Comparison of Etanercept vs. Adalimumab in the Treatment of Ankylosing Spondylitis: An Open-Label Randomized Controlled Crossover Clinical Trial

Background: Anti-tumor necrosis factor biological agents had been proved to have a dramatic effect in ankylosing spondylitis (AS). We aimed to determine the efficacy and safety of crossover effects of adalimumab vs. etanercept in AS patients. Methods: A randomized, open-label crossover study was done in patients with active AS. Patients were randomized into two sequence groups, etanercept first (treatment arm) vs. adalimumab first (control arm) 8 weeks and then switched over for another 8 weeks. The primary endpoints were the difference of the Bath AS activity index and AS disease activity score (ASDAS)crp at week 16. Secondary endpoints were ASDASesr, ASAS20, and ASAS40 response rates and the proportion of patients achieving ASDAS inactive disease and low disease activity at weeks 8 and 16. Patient global assessment and preference was grading on a numerical scale. Results: A total of 21 patients were screened, and 19 of them were randomly allocated into the treatment arm (n = 9) and control arm (n = 9). At baseline, age, sex, Bath AS activity index, and ASDAS of both arms were comparable (p > 0.05). Both arms showed dramatic improvement, whereas no significance was observed between the changes of ASDAScrp (0.90 ± 1.39 vs. 1.24 ± 1.40 at week 8, p = 0.612; 1.02 ± 1.22 vs. 1.26 ± 1.44 at week 16, p = 0.707, respectively). ASAS20 and ASAS40 response rates were also comparable at week 8 (33 vs. 44%, p = 1.000; 22 vs. 22%, p = 1.000) and week 16 (22 vs. 22%, p = 1.000; 22 vs. 22%, p = 1.000), respectively. Both arms were well-tolerated without a serious adverse event. Adalimumab was relatively more favorable by patients in both arms, with a total mean grading score of 0.4 (-5-5, p = 0.218). Conclusion: Etanercept and adalimumab can both dramatically improve disease activity in 16 weeks. Crossover administration of etanercept and adalimumab revealed comparable efficacy and safety. Trial Registration: The protocol was approved by the Institutional Review Board with the register CS08019 from Chung Shan Medical University Hospital (CSMUH), Taichung, Taiwan and registered at ClinicalTrials.gov Protocol Registration and Results System: NCT02489760.

What Is the Clinical Relevance of TNF Inhibitor Immunogenicity in the Management of Patients With Rheumatoid Arthritis?

Tumor necrosis factor-α inhibitors (TNFis) have revolutionized the management of rheumatoid arthritis (RA), however despite considerable progress, only a small proportion of patients maintain long-term clinical response. Selection of, and switching between, biologics is mainly empirical, experiential, and not evidence-based. Most biopharmaceutical proteins (BP) can induce an immune response against the foreign protein component. Immunogenicity and the development of anti-drug antibodies (ADAs) is considered one of the main reasons for loss of therapeutic efficacy (secondary failure). ADAs may neutralize and/or promote clearance of circulating BP with resultant low serum drug levels, loss of clinical response, poor drug survival and adverse events, such as infusion reactions. ADA identification is technically difficult and not standardized, making interpretation of immunogenicity data from published clinical studies challenging. Trough TNFi drug levels correlate with clinical outcomes, exhibiting a "concentration-response" relationship. Measurement of ADA and drug levels may improve patient care and improve cost-effectiveness of BP use. However, in the absence of clinically-validated, reliable assays and consensus guidelines, therapeutic drug monitoring (TDM) and immunogenicity testing have not been widely adopted in routine clinical practice in Rheumatology. Here we discuss the utility and relevance of TDM and immunogenicity testing of TNFis in RA (focusing on the most widely used TNFis globally, with the most available data, i.e., infliximab, adalimumab, and etanercept), the limitations of currently available assays and potential future immunopharmacological strategies to personalize disease management.

Therapeutic drug monitoring with biologic agents in immune mediated inflammatory diseases

Introduction: Biologic therapy has revolutionized the treatment of immune mediated inflammatory diseases (IMID), such as inflammatory bowel disease (IBD), rheumatoid and psoriatic arthritis, ankylosing spondylitis and psoriasis. Nevertheless, some patients exhibit primary nonresponse (PNR) or secondary loss of response (SLR) to biologics. Areas covered: This collaborative review provides data on the role of therapeutic drug monitoring (TDM) in IMID for optimizing biologic therapy including infliximab, adalimumab, certolizumab pegol etanercept and golimumab vedolizumab, secukinumab and ustekinumab. Expert opinion: Most exposure-response relationship studies show a positive correlation between biologic drug concentrations and favorable therapeutic outcomes in IMID with higher drug concentrations typically associated with more objective outcomes. Clinically, reactive TDM rationalizes the management of PNR and SLR to anti-tumor necrosis factor therapy and is emerging as the new standard of care in IBD as it is also more cost-effective than empiric dose escalation. Preliminary data suggest that proactive TDM with the goal to achieve a threshold drug concentration is associated with better therapeutic outcomes when compared to empiric drug optimization and/or reactive TDM of infliximab and adalimumab in IBD. However, more data from well-designed prospective studies are needed to prove the benefit of TDM-based algorithms in real life clinical practice in IMID.