Assessing Immunogenicity of Biologic Drugs in Inflammatory Joint Diseases: Progress Towards Personalized Medicine

Assessing early therapeutic drug monitoring of adalimumab as a predictor of treatment efficacy and immunogenicity in rheumatic diseases: "early therapeutic drug monitoring of adalimumab"

INTRODUCTION

Therapeutic drug monitoring (TDM) in inflammatory rheumatic diseases (RMDs) is gaining interest. However, there are unresolved questions about the best practices for implementing TDM effectively in clinical settings.

OBJECTIVE

The primary objective of this study was to evaluate whether early TDM of adalimumab predicts drug survival at 52 weeks in patients with RMDs. The secondary objective was to identify factors associated with pharmacokinetic failure and treatment discontinuation.

METHODS

A retrospective cohort study included patients aged ≥ 18 years with RMDs who initiated adalimumab therapy. Early TDM was performed within the first 26 weeks, and adalimumab trough levels (ATL) and anti-drug antibodies were measured. Drug survival was assessed at 52 weeks and defined as the time from adalimumab initiation to discontinuation for any reason. Multivariate analyses were conducted to identify factors influencing outcomes.

RESULTS

The study included 194 patients, of whom 56.7% exhibited ATL below the therapeutic range during the first 26 weeks. In the multivariate analysis, subtherapeutic concentrations were significantly associated with higher weight (OR = 1.02; p = 0.040) and ankylosing spondylitis diagnosis (OR = 3.68; p < 0.001). At 52 weeks, 43.8% of patients had discontinued adalimumab. Low ATL (< 1 µg/mL) was strongly associated with treatment discontinuation (OR = 7.31; p < 0.001), while concomitant methotrexate reduced this risk (OR = 0.46; p = 0.026).

CONCLUSIONS

Early TDM of adalimumab predicts drug persistence and underscores its clinical relevance as a proactive tool to guide personalized treatment and reduce the risk of treatment failure. These findings highlight the importance of incorporating TDM into routine practice to optimize therapeutic outcomes. Key Points • Early TDM of adalimumab in rheumatic diseases shows that low drug exposure predicts reduced drug survival at 52 weeks. • Approximately half of the patients exhibit low adalimumab exposure with the standard dose (40 mg every other week). • Body weight and methotrexate use significantly impact adalimumab levels. • Immunogenicity, found in 14.4% of patients with low ADL levels, underscores the need for early ADA detection to prevent non-response and discontinuation.

Stopping of adalimumab in juvenile idiopathic arthritis-associated uveitis (ADJUST): a multicentre, double-masked, randomised controlled trial

BACKGROUND

Adalimumab is an effective treatment for juvenile idiopathic arthritis-associated uveitis. Data are scarce on the effects of discontinuing adalimumab after control of the disease had been reached. We aimed to assess efficacy and safety of discontinuing treatment in patients with juvenile idiopathic arthritis-associated uveitis.

METHODS

We conducted a multicentre, double-masked, randomised, placebo-controlled trial at 20 ophthalmology and rheumatology clinics across the USA, the UK, and Australia. Patients aged at least 2 years who had controlled arthritis and uveitis for at least 1 year on adalimumab were randomly assigned in a 1:1 ratio using a web-based system to receive adalimumab or placebo, administered subcutaneously every 2 weeks until the 48-week visit or treatment failure. The primary outcome was the time to treatment failure, defined by recurrence of uveitis or arthritis; all participants were included in the primary and safety analysis. Unmasking occurred at treatment failure, and patients were offered open-label adalimumab through 48 weeks of follow-up. This trial was registered with ClinicalTrials.gov (NCT03816397).

FINDINGS

87 patients were enrolled from March 3, 2020, to Feb 14, 2024, whereafter the prespecified interim stopping criteria were met and enrolment was stopped. One patient in each group dropped out but data were included in analyses. Six (14%) of 43 patients in the adalimumab group and 30 (68%) of 44 patients in the placebo group had treatment failure (hazard ratio 8·7, 95% CI 3·6-21·2; p<0·0001). The median time to treatment failure in the placebo group was 119 days (IQR 84-243). The median time to re-establishing sustained control of inflammation in the placebo group after restarting adalimumab was 105 days (63-196). 226 non-serious adverse events occurred in the adalimumab group (7·5 events per person-year, 95% CI 6·5-8·5), and 115 non-serious adverse events occurred in the placebo group (6·8 events per person-year, 5·6-8·1). Four serious adverse events were reported, all in the adalimumab group.

INTERPRETATION

Discontinuing adalimumab led to higher rates of recurrence of uveitis, arthritis, or both in patients with previously controlled juvenile idiopathic arthritis-associated uveitis. However, all patients who had treatment failure successfully regained control of inflammation by the end of the 48-week study period after restarting adalimumab.

FUNDING

US National Institutes of Health (National Eye Institute).

Adalimumab Autoantibodies in Uveitis Patients: Do We Need Routine Drug Monitoring?

BACKGROUND

Adalimumab, an anti-TNF-α biologic agent, has emerged as a principal treatment option for patients with non-infectious uveitis. The influence of adalimumab anti-drug antibodies (AAA) on the efficacy of adalimumab therapy is not yet fully understood. We aim to understand their clinical implications in the context of therapeutic drug monitoring and the factors contributing to the formation of these antibodies.

METHODS

We conducted a retrospective analysis of 114 patients with non-infectious uveitis who developed AAA while undergoing adalimumab therapy.

RESULTS

Among the 114 AAA-positive uveitis patients, a significant correlation was observed between AAA levels and reduced adalimumab serum levels (r = -0.58, p < 0.001). The mean time to AAA detection was 2.1 years (range 0.1-11.9 years), with 45.6% of cases identified through routine testing. If AAA levels were initially low, subsequent measurements for AAA were more likely to become negative during treatment (r = 0.63, p < 0.001). Higher AAA concentrations were associated with a shorter time to detection (r = -0.27, p = 0.01) and younger age (r = -0.21, p = 0.03). There was a trend, though no significant influence, of concomitant immunosuppression with prednisolone ≤ 7.5 mg or methotrexate on antibody formation (p = 0.18). No significant difference was observed in AAA levels between uveitis subtypes.

CONCLUSIONS

Higher AAA concentrations are associated with lower adalimumab serum levels in uveitis patients. Routine clinical testing is essential for optimal therapeutic drug monitoring to prevent early loss of effectiveness.

Therapeutic serum level for adalimumab in rheumatoid arthritis: explorative analyses of data from a randomised phase III trial

OBJECTIVES

The objectives of this study are to identify a therapeutic serum level for adalimumab associated with remission and low disease activity in patients with rheumatoid arthritis.

METHODS

Associations between serum adalimumab trough levels and disease activity were examined using longitudinal data from a 48-week randomised phase III trial including patients with tumour necrosis factor inhibitor-naïve rheumatoid arthritis with active disease starting adalimumab treatment. Disease activity was classified according to 28-joint Disease Activity Score (DAS28)-erythrocyte sedimentation rate and C reactive protein (CRP) levels.

RESULTS

Adalimumab trough levels were recorded longitudinally for 336, 330 and 302 patients at weeks 12, 24 and 48, respectively. All patients received concomitant methotrexate. Median adalimumab trough levels were 6.4 mg/L (IQR 3.4-9.5) at week 12, 7.5 mg/L (IQR 3.5-10.9) at week 24 and 7.6 mg/L (IQR 3.6-12.0) at week 48. In serial serum samples from weeks 12, 24 and 48, trough levels ≥3.9 mg/L were associated with DAS28 remission (OR 3.88 (95% CI 1.80, 8.38), p<0.001) and lower CRP levels (p<0.001). Week 12 trough levels ≥3.5 mg/L were associated with DAS28 low disease activity at week 24 (OR 2.62 (1.50, 4.56), p<0.001) and remission at week 48 (OR 1.99 (1.02, 3.88), p=0.04), as well as lower CRP levels at both time points (p<0.001).

CONCLUSION

Adalimumab trough levels above 4.0 mg/L were associated with remission/low disease activity throughout the first year of adalimumab therapy and can be considered a lower target level for therapeutic drug monitoring of adalimumab therapy.

Proactive therapeutic drug monitoring of biologic drugs in adult patients with inflammatory bowel disease, inflammatory arthritis, or psoriasis: a clinical practice guideline

CLINICAL QUESTION

In adult patients with inflammatory bowel disease, inflammatory arthritis (rheumatoid arthritis, spondyloarthritis, psoriatic arthritis), or psoriasis taking biologic drugs, does proactive therapeutic drug monitoring (TDM) improve outcomes as compared with standard care?

CONTEXT AND CURRENT PRACTICE

Standard care for immune mediated inflammatory diseases includes prescribing biologic drugs at pre-determined doses. Dosing may be adjusted reactively, for example with increased disease activity. In proactive TDM, serum drug levels and anti-drug antibodies are measured irrespective of disease activity, and the drug dosing is adjusted to achieve target serum drug levels, usually within pre-specified therapeutic ranges. The role of proactive TDM in clinical practice remains unclear, with conflicting guideline recommendations and emerging evidence from randomised controlled trials.

THE EVIDENCE

Linked systematic review and pairwise meta-analysis which identified 10 trials including 2383 participants. Inflammatory bowel disease, inflammatory arthritis, and psoriasis were grouped together as best current research evidence on proactive TDM did not suggest heterogeneity of effects on outcomes of interest. Proactive TDM of intravenous infliximab during maintenance treatment may increase the proportion of patients who experience sustained disease control or sustained remission without considerable additional harm. For adalimumab, it remains unclear if proactive TDM during maintenance treatment has an effect on sustained disease control or sustained remission. At induction (start) of treatment, proactive TDM of intravenous infliximab may have little or no effect on achieving remission. No eligible trial evidence was available for proactive TDM of adalimumab at induction (start) of treatment. No eligible trial evidence was available for proactive TDM of other biologic drugs in maintenance or at induction (start) of treatment.

RECOMMENDATIONS

The guideline panel issued the following recommendations for patients with inflammatory bowel disease, inflammatory arthritis, or psoriasis:1. A weak recommendation in favour of proactive TDM for intravenous infliximab during maintenance treatment2. A weak recommendation against proactive TDM for adalimumab and other biologic drugs during maintenance treatment3. A weak recommendation against proactive TDM for intravenous infliximab, adalimumab, and other biologic drugs during induction (start) of treatment.

UNDERSTANDING THE RECOMMENDATIONS

When considering proactive TDM, clinicians and patients should engage in shared decision making to ensure patients make choices that reflect their values and preferences. The availability of laboratory assays to implement proactive TDM should also be considered. Further research is warranted and may alter recommendations in the future.

HOW THIS GUIDELINE WAS CREATED

An international panel including patient partners, clinicians, and methodologists produced these recommendations based on a linked systematic review and pairwise meta-analysis which identified 10 trials including 2383 participants. The panel followed standards for trustworthy guidelines and used the GRADE approach, explicitly considering the balance of benefits and harms and burdens of treatment from an individual patient perspective.

Proactive therapeutic drug monitoring of biologic drugs in patients with inflammatory bowel disease, inflammatory arthritis, and psoriasis: systematic review and meta-analysis

Objective

To address the efficacy and safety of proactive therapeutic drug monitoring of biologic drugs for patients with inflammatory bowel disease, inflammatory arthritis, and psoriasis.

Design

Systematic review and meta-analysis.

Data sources

Medline, Embase, Central, and CINAHL, from database inception to 23 May 2024.

Eligibility criteria for selecting studies

Trials including people with inflammatory bowel disease, inflammatory arthritis, and psoriasis were selected. Selected trials also randomly assigned people to either proactive therapeutic drug monitoring of tumour necrosis factor-alpha inhibitors or other biologic drugs in the intervention group, and to either no therapeutic drug monitoring or standard care in the control group. Reviewers worked independently and in duplicate to screen search records and collect data from eligible trials. For each outcome, a frequentist, pairwise, random effects meta-analysis was done and the certainty of evidence was assessed using GRADE (grading of recommendations, assessment, development, and evaluations).

Results

Of 10 eligible trials identified, reporting on 2383 patients, two investigated induction with infliximab (533 patients), four assessed maintenance with infliximab (901 patients), and three assessed maintenance with adalimumab (710 patients). One trial was of maintenance with infliximab, adalimumab, and etanercept (239 patients). For patients who had induction with infliximab, the effects of proactive therapeutic drug monitoring on remission and adverse events were uncertain. Low certainty evidence suggested that proactive therapeutic drug monitoring may have little or no effect on disease activity, physical function, mental health, and quality of life. For patients who had maintenance with infliximab, low certainty evidence suggested that proactive therapeutic drug monitoring may increase the proportion of patients who had sustained disease control or remission (relative risk 1.26 (95% confidence interval (CI) 1.14 to 1.40), absolute risk difference of 146 more per 1000 patients treated for one year (95% CI 78 to 224). Additionally, this treatment and monitoring may reduce disease worsening, and may have little or no effect on disease activity, physical function, mental health, and quality of life. The effects of proactive therapeutic drug monitoring of infliximab on adverse events and formation of anti-drug antibodies were uncertain. For patients who had maintenance with adalimumab, the effects of proactive therapeutic drug monitoring were uncertain.

Conclusion

Proactive therapeutic drug monitoring of infliximab during maintenance may help patients to have sustained disease control or remission. No compelling evidence supported the effectiveness of proactive therapeutic drug monitoring of infliximab during induction or proactive therapeutic drug monitoring of adalimumab during maintenance.

Systematic review registration

https://osf.io/x4m28/.

Is therapeutic drug monitoring a dancing partner for TNF-α inhibitors in real-world practice? Answers from an updated systematic review and meta-analysis

INTRODUCTION

This systematic review aimed to determine the effect of therapeutic drug monitoring (TDM) for tumor necrosis factor-α inhibitors (TNF-αI) in immune-mediated inflammatory diseases (IMIDs) based on real-world evidence, as results from published meta-analyses based on randomized controlled trials (RCTs) may not fully capture the nuances of clinical practice due to strict criteria.

METHODS

We searched PubMed, Embase, and the Cochrane Library up to 1 August 2023. Cohort studies comparing TDM (proactive and reactive) with empirical management were included. Primary outcome was effectiveness [for IBDs: clinical remission; for rheumatic diseases: clinical remission or low disease activity], with certainty of evidence appraised using the GRADE approach. Secondary outcomes included treatment failure, serious adverse events (SAEs), IMIDs-related surgeries or hospitalizations, and anti-drug antibodies (ADAs) development risk.

RESULTS

Twenty-four cohort studies were included and almost all were on infliximab. For IBDs, compared with empirical management, proactive TDM significantly improved clinical remission (RR = 1.15, 95% CI = 1.04-1.28), reduced IBDs-related surgeries (RR = 0.46, 95% CI = 0.26-0.81), hospitalizations (RR = 0.60, 95% CI = 0.43-0.83), SAEs (RR = 0.23, 95% CI = 0.07-0.76), and ADAs development risk (RR = 0.34, 95% CI = 0.19-0.60). Reactive TDM significantly lowered hospitalization rates and might be cost-effective. Proactive TDM outperformed reactive TDM in secondary outcomes. For rheumatic diseases, benefits of TDM were inconclusive due to limited evidence.

CONCLUSIONS

Real-world evidence supports proactive TDM of TNF-αI (particularly infliximab) in IBDs to improve effectiveness, safety, and immunogenicity. However, benefits of TDM for different TNF-αI in other IMIDs remain uncertain.

PROTOCOL REGISTRATION

www.crd.york.ac.uk/ PROSPERO identifier is CRD42022370846.

A phase 3, randomized, double-blind, active-controlled clinical trial to compare BAT1806/BIIB800, a tocilizumab biosimilar, with tocilizumab reference product in participants with moderate-to-severe rheumatoid arthritis with inadequate response to methotrexate: treatment period 2 analysis (week 24 to week 48)

BACKGROUND

Equivalent efficacy and comparable pharmacokinetic, immunogenicity, and safety profiles of the biosimilar BAT1806/BIIB800 and reference tocilizumab (TCZ) in participants with moderate-to-severe rheumatoid arthritis (RA) have been reported up to week 24 (treatment period [TP] 1) of the phase 3 study. Here we present results for TP2 (study weeks 24-48).

METHODS

In this phase 3, multicenter, multiregional, double-blind, active-controlled, equivalence study, participants with active RA despite methotrexate were randomized (1:1:2) to intravenous administration of 8 mg/kg TCZ every 4 weeks to week 48 (TCZ group), or TCZ to week 24 followed by BAT1806/BIIB800 to week 48 (TCZ to BAT1806/BIIB800 group), or BAT1806/BIIB800 to week 48 (BAT1806/BIIB800 group). Efficacy in TP2 was evaluated using American College of Rheumatology (ACR) response criteria (ACR20/50/70) and change from baseline in Disease Activity Score on 28 joints (DAS28). Pharmacokinetics (trough levels), safety, and immunogenicity were also evaluated.

RESULTS

Of 621 randomized participants, 577 (92.9%) completed TP1 and entered TP2 (TCZ: N = 145 [93.5%]; TCZ to BAT1806/BIIB800: N = 142 [92.2%]; BAT1806/BIIB800: N = 290 [92.9%]). Proportions of ACR20 responders were similar between treatment groups throughout TP2 (87.8%, 90.3%, and 90.4%, respectively, at week 48), as were proportions of ACR50 and ACR70 responders, and reduction in DAS28. Drug trough levels and antidrug antibody incidences were comparable between the treatment groups. Adverse events were balanced across the treatment groups and no fatal events were reported.

CONCLUSION

In TP2, efficacy, safety, immunogenicity, and pharmacokinetic profiles were comparable between the TCZ, TCZ to BAT1806/BIIB800, and BAT1806/BIIB800 groups.

TRIAL REGISTRATION

NCT03830203 and EudraCT 2018-002202-31.

Biologics or Janus Kinase Inhibitors in Rheumatoid Arthritis Patients Who are Insufficient Responders to Conventional Anti-Rheumatic Drugs

Rheumatoid arthritis (RA) is a chronic immune-mediated inflammatory disease which can induce progressive disability if not properly treated early. Over the last 20 years, the improvement of knowledge on the pathogenesis of the disease has made available several drugs targeting key elements of the pathogenetic process, which now represent the preferred treatment option after the failure of first-line therapy with conventional drugs such as methotrexate (MTX). To this category of targeted drugs belong anti-cytokine or cell-targeted biological agents and more recently also Janus kinase inhibitors (JAKis). In the absence to date of specific biomarkers to guide the therapeutic choice in the context of true precision medicine, the choice of the first targeted drug after MTX failure is guided by treatment cost (especially after the marketing of biosimilar products) and by the clinical characteristics of the patient (age, sex, comorbidities and compliance) and the disease (presence or absence of autoantibodies and systemic or extra-articular manifestations), which may influence the efficacy and safety profile of the available products. This viewpoint focuses on the decision-making process underlying the personalized approach to RA therapy and will analyse the evidence in the literature supporting the choice of individual products and in particular the differential choice between biological drugs and JAKis.

An observer-blind, randomised, placebo-controlled, phase 1, single ascending dose study of dengue monoclonal antibody in healthy adults in Australia

BACKGROUND

Dengue is highly prevalent in Asia and Latin America and has no specific dengue antiviral treatment. A recombinant monoclonal antibody (VIS513) that neutralises all four serotypes of the dengue virus has been developed in India. After confirmation of safety and efficacy in preclinical studies, it was tested in a first-in-human study to assess the safety and pharmacokinetics.

METHODS

This was a partially blind (observer-blind), randomised, placebo-controlled, phase 1, single ascending dose study in Australia. Participants were dengue naive, healthy adults (aged 18-45 years) with no clinically significant disorders or immunosuppressive conditions. Four dose levels of dengue monoclonal antibody (ie, 1 mg/kg, 3 mg/kg, 7 mg/kg, and 12 mg/kg; n=4 for 1 mg/kg and n=10 each for 3 mg/kg, 7 mg/kg, and 12 mg/kg doses) were assessed in a dose-ascending way with a placebo control (n=2 for each dose cohort, total n=6) for each cohort except for 1 mg/kg. Within each cohort, participants were first randomly assigned (1:1) in a sentinel sub-cohort and then randomly assigned (9:1) in an expansion sub-cohort to dengue monoclonal antibody or placebo except for the 1 mg/kg cohort. Participants, investigators, and outcome assessors were masked and treatment administrators were not masked. 40 participants received a single intravenous injection or infusion of either dengue monoclonal antibody or placebo over a period of 3 min to 2 h and were followed up until day 85. The primary outcomes were proportion of participants with adverse events and serious adverse events (SAEs) up to 84 days after dosing whereas the secondary outcomes were to assess the pharmacokinetic profile of dengue monoclonal antibody and to assess the presence of anti-drug antibody (ADA) to dengue monoclonal antibody. All participants were included in the safety analysis and the pharmacokinetic population involved participants receiving dengue monoclonal antibody. This study is registered with ClinicalTrials.gov, NCT03883620.

FINDINGS

Between March 22 and Dec 23, 2019, 40 healthy adults were randomly assigned and all completed the study. There were no SAEs reported. None of the placebo recipients (n=6) reported any adverse events. 31 (91%) of 34 participants receiving dengue monoclonal antibody reported 143 adverse events (1 mg/kg: four [100%] of four participants; 3 mg/kg: ten [100%] of ten participants; 7 mg/kg: seven [70%] of ten participants; 12 mg/kg: ten [100%] of ten participants). Of these 143 adverse events, 80 were treatment-related adverse events in 28 (82%) of 34 participants. Headache (16 [47%] of 34), infusion reaction (11 [32%] of 34), lymphopenia (seven [21%] of 34), fatigue (five [15%] of 34), and pyrexia (four [12%] of 34) were the most common reactions. Infusion reactions were reduced in the 7 mg/kg (two [20%] of ten participants) and 12 mg/kg (three [30%] of ten) cohorts with paracetamol premedication compared with the 3 mg/kg cohort (five [50%] of ten). The majority of adverse events were grade 1 or grade 2 in severity, and resolved completely. Median maximum serum concentrations ranged from 28 μg/mL (1 mg/kg) to 525 μg/mL (12 mg/kg). The median elimination half-life ranged from 775 h (1 mg/kg) to 878 h (12 mg/kg). No ADA against dengue monoclonal antibody was detected.

INTERPRETATION

Dengue monoclonal antibody was safe and well tolerated. It showed a dose-proportionate increase in pharmacokinetic exposure. These data support further evaluation of dengue monoclonal antibody in patients with dengue for safety and efficacy.

FUNDING

Serum Institute of India.

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.

Clinical pharmacokinetics and pharmacodynamics of oral systemic nonbiologic therapies for psoriasis patients

INTRODUCTION

Psoriasis is a chronic inflammatory immune condition. Treatments for psoriasis vary with disease severity, ranging from topicals to systemic biologic agents. The pharmacokinetic (PK) and pharmacodynamic (PD) properties of these therapies establish drug efficacy, toxicity, and optimal dosing to ensure therapeutic drug levels are sustained and adverse effects are minimized.

AREAS COVERED

A literature search was performed on PubMed, Google Scholar, and Ovid MEDLINE for PK and PD, efficacy, and safety data regarding oral systemic nonbiologic therapies utilized for moderate-to-severe plaque psoriasis. The findings were organized into sections for each drug: oral acitretin, methotrexate, cyclosporine, apremilast, tofacitinib, and deucravacitinib.

EXPERT OPINION

Some psoriasis patients may not respond to initial therapy. Ongoing research is evaluating genetic polymorphisms that may predict an improved response to specific medications. However, financial and insurance barriers, as well as limited genetic polymorphisms correlated with treatment response, may restrict the implementation of genetic testing necessary to personalize treatments. How well psoriasis patients adhere to treatment may contribute greatly to variation in response. Therapeutic drug monitoring may help patients adhere to treatment, improve clinical response, and sustain disease control.

Clinical consequences of infliximab immunogenicity and the effect of proactive therapeutic drug monitoring: exploratory analyses of the randomised, controlled NOR-DRUM trials

BACKGROUND

Antidrug antibodies to TNF inhibitors might affect clinical outcomes. Proactive therapeutic drug monitoring allows for early detection of antidrug antibodies and might reduce negative clinical consequences. We aimed to explore how antidrug antibodies to the TNF inhibitor infliximab influence treatment outcomes, and to assess the effect of proactive therapeutic drug monitoring.

METHODS

This was a predefined exploratory analysis of data from the randomised, controlled NOR-DRUM trials. The trials were conducted in rheumatology, gastroenterology, and dermatology departments at 21 Norwegian hospitals. Adult patients (aged 18-75 years) with immune-mediated inflammatory diseases were randomly assigned to proactive therapeutic drug monitoring or standard infliximab dosing in the NOR-DRUM A trial (30-week follow-up) and the NOR-DRUM B trial (52-week follow-up). Antidrug antibodies were assessed with a drug-sensitive assay before each infusion. The outcomes of remission (at week 30), disease worsening (during 52 weeks), infusion reactions, and infliximab discontinuation were assessed according to the presence of antidrug antibodies and use of therapeutic drug monitoring.

FINDINGS

Between March 1, 2017, and Dec 12, 2019, 616 patients were included in the NOR-DRUM trials, of whom 615 had at least one serum infliximab and antidrug antibody assessment and were included in the present analyses. Mean age was 45 years (IQR 32-56), 305 (50%) patients were women, and 310 (50%) patients were men. Antidrug antibodies were detected in 147 (24%) patients. Remission at week 30 occurred in 25 (35%) of 72 patients with antidrug antibodies and 180 (54%) of 335 without antidrug antibodies (risk ratio 0·62 [95% CI 0·45-0·86]; p=0·0037). In patients with antidrug antibodies compared with patients without antidrug antibodies, higher rates were found for: disease worsening over 52 weeks (0·76 per person-year vs 0· 35 per person-year, hazard ratio [HR] 2·02 [95% CI 1·33-3·07]; p=0·0009), infusion reactions (0·16 per person-year vs 0·03 per person-year, HR 17·02 [6·98-41·47]; p<0·0001), and infliximab discontinuation (1·00 per person-year vs 0·20 per person-year, HR 6·64 [4·84-9·11]; p<0·0001). These associations were more pronounced in patients with high concentrations of antidrug antibodies than in those with low concentrations of antidrug antibodies. Independent of antibody status, therapeutic drug monitoring was associated with a lower risk of disease worsening (HR 0·41 [0·29-0·59]; p=0·0001) or an infusion reaction (HR 0·30 [0·12-0·73]; p=0·0076), and was associated with an increase in the rate of infliximab discontinuation (HR 1·37 [1·02-1·83]; p=0·037).

INTERPRETATION

In patients where antidrug antibodies were detected, remission was less likely to be reached and sustained, and infusion reaction or discontinuation of infliximab was more likely. Timely detection of antidrug antibodies by proactive therapeutic drug monitoring facilitated treatment decisions that reduced the negative consequences, both regarding infliximab effectiveness and safety. This highlights the role of proactive therapeutic drug monitoring in optimising infliximab therapy.

FUNDING

Inter-regional KLINBEFORSK grants and South-Eastern Norway Regional Health Authority grants.

Biologics, theranostics, and personalized medicine in drug delivery systems

The progress in human disease treatment can be greatly advanced through the implementation of nanomedicine. This approach involves targeted and cell-specific therapy, controlled drug release, personalized dosage forms, wearable drug delivery, and companion diagnostics. By integrating cutting-edge technologies with drug delivery systems, greater precision can be achieved at the tissue and cellular levels through the use of stimuli-responsive nanoparticles, and the development of electrochemical sensor systems. This precision targeting - by virtue of nanotechnology - allows for therapy to be directed specifically to affected tissues while greatly reducing side effects on healthy tissues. As such, nanomedicine has the potential to transform the treatment of conditions such as cancer, genetic diseases, and chronic illnesses by facilitating precise and cell-specific drug delivery. Additionally, personalized dosage forms and wearable devices offer the ability to tailor treatment to the unique needs of each patient, thereby increasing therapeutic effectiveness and compliance. Companion diagnostics further enable efficient monitoring of treatment response, enabling customized adjustments to the treatment plan. The question of whether all the potential therapeutic approaches outlined here are viable alternatives to current treatments is also discussed. In general, the application of nanotechnology in the field of biomedicine may provide a strong alternative to existing treatments for several reasons. In this review, we aim to present evidence that, although in early stages, fully merging advanced technology with innovative drug delivery shows promise for successful implementation across various disease areas, including cancer and genetic or chronic diseases.

Cardiovascular Risk Factors and the Risk of Discontinuation of Advanced Therapies Due to Treatment Failure in Rheumatoid Arthritis: Results From the Ontario Best Practices Research Initiative

OBJECTIVES

Our goal was to investigate whether cardiovascular disease (CVD) risk factors are associated with the retention of biologic disease-modifying antirheumatic drugs (bDMARDs) or targeted-synthetic DMARDs (tsDMARDs) in patients with rheumatoid arthritis (RA).

METHODS

We included participants in the Ontario Best Practices Initiative RA registry who initiated their first bDMARD or tsDMARD. Participants were grouped by the number of baseline CVD risk factors (0, 1, or ≥2). The primary outcome was time-to-discontinuation of therapy for any reason. Secondary outcomes included discontinuation for primary failure, secondary failure, or due to adverse events. Competing risks hazards model, adjusted for clinically important confounders, estimated the association between CVD risk factors and treatment retention.

RESULTS

The sample included 872 patients, of which 58% (n = 508) discontinued their b/tsDMARD after a median of 13 months from the time of initiation. The most common causes for treatment discontinuation were primary failure (n = 72), secondary failure (n = 126), or adverse events (n = 133). Patients with no CVD risk factors experienced significantly longer treatment survival compared to patients with 1 or ≥2 CVD risk factors. In multivariable-adjusted analysis, there was no association between all-cause discontinuation and CVD risk factors. However, there was a significant association between the presence of >1 CVD risk factor and treatment discontinuation, notably due to secondary treatment failure, but not due to adverse events.

CONCLUSION

Multiple CVD risk factors increase the risk of treatment failure in RA, particularly for secondary treatment failure. To improve patient outcomes, future research should focus on developing strategies to identify early treatment nonresponse and investigate the potential modifiability of this association.

HLA-DQA1∗05 Genotype and Immunogenicity to Tumor Necrosis Factor-α Antagonists: A Systematic Review and Meta-analysis

BACKGROUND & AIMS

Identifying patients at high risk of immunogenicity is important when selecting tumor necrosis factor (TNF)-α antagonists in patients with immune-mediated inflammatory diseases (IMIDs). We evaluated the association HLA-DQA1∗05 genotype and risk of immunogenicity with TNF-α antagonists.

METHODS

Through a systematic review through July 14, 2022, we identified studies in patients with IMIDs treated with TNF-α antagonists, which reported the risk of immunogenicity and/or secondary loss of response in patients with HLA-DQA1∗05 variants. Primary outcome was risk of immunogenicity. We performed random effects meta-analysis and used GRADE to appraise certainty of evidence.

RESULTS

On meta-analysis of 13 studies (3756 patients; median follow-up, 12 months; 41% with variants), HLA-DQA1∗05 variants were associated with 75% higher risk of immunogenicity compared with non-carriers (relative risk, 1.75; 95% confidence interval, 1.37-2.25) with considerable heterogeneity (I2 = 62%) (low certainty evidence). Positive and negative predictive values of HLA-DQA1∗05 variants for predicting immunogenicity were 30% and 80%, respectively. Proactive therapeutic drug monitoring, but not concomitant use of IMMs, IMIDs, and TNF-α antagonist-type, modified this association. Patients with HLA-DQA1∗05 variants experienced 2.2-fold higher risk of secondary loss of response (6 cohorts; relative risk, 2.24; 95% confidence interval, 1.67-3.00; I2 = 0%) (moderate certainty evidence).

CONCLUSION

Variants in HLA-DQA1∗05 are associated with an increased risk in immunogenicity and secondary loss of response in patients with IMIDs treated with TNF-α antagonists. However, the positive and negative predictive value is moderate, and decisions on concomitant use of IMMs to prevent immunogenicity should be individualized based on all factors that influence drug clearance.

Adalimumab Therapeutic Drug Monitoring Improves Treatment Outcome in Patients with Psoriasis

Therapeutic drug monitoring (TDM) or the measurement of drug concentrations (ideally at trough level) and antidrug antibodies are important tools for optimizing biologic therapy. Limited studies evaluated TDM in dermatological indications. A retrospective study of 170 patients with psoriasis who were treated with adalimumab and received TDM reported that adalimumab TDM is practical and promising in routine psoriasis care. However, TDM interpretation requires careful attention to the clinical context to address the controversies and challenges.

Biosimilars in the treatment of rheumatoid arthritis: a pharmacokinetic overview

INTRODUCTION

As of May 2023, 19 and 18 biosimilars have been approved for the treatment of rheumatoid arthritis (RA) by the European Medicines Agency (EMA) and United States Food and Drug Administration (US FDA) respectively.

AREA COVERED

Pharmacokinetic results of phase 1 studies of approved biosimilars were reviewed by systematic literature search. The impact of immunogenicity on the pharmacokinetic data and clinical response was assessed, and the potential benefit of monitoring serum concentrations of biologic drugs is discussed. The advantage of subcutaneous CT-P13 (an infliximab biosimilar) in clinical practice is reviewed.

EXPERT OPINION

Biosimilars are approved based on the totality of evidence including comparable physiochemical properties, PK / PD profiles, and clinical efficacy and safety to the originator. To utilize biosimilars more effectively, physicians should be aware of the utility of combination DMARD therapy to reduce immunogenicity and maintain efficacy and PK profile. PK monitoring, however, is not currently recommended in clinical practice. CT-P13 subcutaneous (SC) is the first SC infliximab used for treatment of RA patients. Based on data from clinical studies and the real world, SC-infliximab is an attractive therapeutic option compared to IV formulations of infliximab based on its efficacy, pharmacokinetics, patient-reported outcomes, and safety profile.

HLA-DQ2 is associated with anti-drug antibody formation to infliximab in patients with immune-mediated inflammatory diseases

BACKGROUND

Immunogenicity to tumour necrosis factor inhibitors is a significant clinical problem leading to treatment failure and adverse events. The study aimed to assess human leukocyte antigen (HLA) associations with anti-drug antibody (ADAb) formation to infliximab.

METHODS

Immune-mediated inflammatory disease patients on infliximab therapy (n = 612) were included. Neutralising ADAb were assessed with a drug-sensitive assay. Next generation sequencing-based HLA typing was performed.

RESULTS

Overall, 147 (24%) patients developed ADAb. Conditional analyses indicated HLA-DQB1 (p = 1.4 × 10^-6 ) as a primary risk locus. Highest risk of ADAb was seen when carrying at least one of the HLA-DQ2 haplotypes; DQB1*02:01-DQA1*05:01 or DQB1*02:02-DQA1*02:01 (OR 3.18, 95% CI 2.15-4.69 and p = 5.9 × 10^-9 ). Results were consistent across diseases and when adjusting for concomitant immunomodulator. Computational predictions indicated that these HLA-DQ2 haplotypes bind to peptide motifs from infliximab light chain.

CONCLUSION

A genome-wide significant association between two HLA-DQ2 haplotypes and the risk of ADAb formation to infliximab was identified, suggesting that HLA-DQ2 testing may facilitate personalised treatment decisions.