Adalimumab Concentrations Research Articles

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

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. 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). 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. 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.

Ultrasound transmural healing correlates with higher adalimumab drug concentration in Crohn's disease only in the short-term.

Anti-TNF drugs have revolutionized the treatment of Crohn's disease (CD) and have set new therapeutic targets. A direct correlation between anti-TNF trough levels and endoscopic healing in IBD patients has been established, but the association between drug levels and transmural healing assessed by ultrasound is not yet clearly defined. To evaluate the correlation between the serum concentration of adalimumab (ADA) and sonographic transmural healing in CD patients at different times during the follow-up of patients. In this retrospective, cross-sectional study all patients with CD who were undergoing treatment with ADA in our center were included. Intestinal ultrasound (IUS) was performed before the initiation of the drug and for response monitoring. ADA serum-through levels were compared between patients with and without transmural healing at different periods of time. 92 patients were included, all patients showed signs of inflammatory activity in the baseline IUS. In the IUS monitoring of the response to ADA, 34 (34.8%) patients presented transmural healing. Among patients in the first year of treatment, those with sonographic healing showed higher median levels than patients without transmural healing (12.0 µg/mL vs. 9.3 µg/mL, respectively; p= 0.007). There was no correlation found between adalimumab levels and sonographic healing in patients undergoing treatment for over a year. Higher adalimumab through levels were corelated with transmural healing with ultrasound during the first year of treatment. This correlation was not found after one year of treatment.

Evaluating the Performance of Two Automated Anti-drug Antibodies Assays for Infliximab and Adalimumab Without Acid Dissociation

Monitoring anti-drug antibodies (ADAs) to infliximab and adalimumab is critical to treatment management in various autoimmune disorders. The growing need for proactive therapeutic monitoring further requires the detection of ADAs in the presence of measurable concentrations of infliximab or adalimumab. To provide robust analytical assays for clinical application, we evaluated two automated immunoassays developed using ImmunoCAP™ technology and based on the bridging format to measure serum ADAs to infliximab and adalimumab respectively. Without an acid-dissociation step, these research prototype assays can detect a positive control monoclonal ADA towards infliximab and adalimumab, ranging from < 25 ng/ml to 10,000 ng/mL. Both assays exhibit imprecision less than 20% at different ADA titer levels and can distinguish ADAs towards different drug targets. In method comparison using authentic patient samples, the quantitative results of the ADA assays are not directly comparable to two existing clinical immunoassays for ADAs (correlation coefficient rs = 0.673 for infliximab ADAs; rs = 0.510 for adalimumab ADAs), presumably due to the lack of commutable ADA standards and the polyclonal nature of ADAs. Nevertheless, there is qualitative agreement between the methods when evaluating putative positive and negative patient samples (overall agreement 0.83 for infliximab ADAs; 0.76 for adalimumab ADAs). Biotin and high levels of rheumatoid factors may interfere with the performance of the automated assays due to competitive binding with the biotinylated drug and non-specific formation of bridging complexes. The two ImmunoCAP assays can provide new analytical methods for proactive therapeutic monitoring of adalimumab and infliximab.Graphical

A prediction method for the individual serum concentration and therapeutic effect for optimizing adalimumab therapy in inflammatory bowel disease.

Adalimumab (ADM) therapy is effective for inflammatory bowel disease (IBD), but a significant number of IBD patients lose response to ADM. Thus, it is crucial to devise methods to enhance ADM's effectiveness. This study introduces a strategy to predict individual serum concentrations and therapeutic effects to optimize ADM therapy for IBD during the induction phase. We predicted the individual serum concentration and therapeutic effect of ADM during the induction phase based on pharmacokinetic and pharmacodynamic (PK/PD) parameters calculated using the empirical Bayesian method. We then examined whether the predicted therapeutic effect, defined as clinical remission or treatment failure, matched the observed effect. Data were obtained from 11 IBD patients. The therapeutic effect during maintenance therapy was successfully predicted at 40 of 47 time points. Moreover, the predicted effects at each patient's final time point matched the observed effects in 9 of the 11 patients. This is the inaugural report predicting the individual serum concentration and therapeutic effect of ADM using the Bayesian method and PK/PD modelling during the induction phase. This strategy may aid in optimizing ADM therapy for IBD.

Efficacy and safety of infliximab and adalimumab in inflammatory bowel disease patients

IntroductionInflammatory bowel disease (IBD), consists of two primary types: Ulcerative Colitis (UC) and Crohn’s Disease (CD). Infliximab (IFX) and Adalimumab (ADA) are frequently utilized in the management of moderate to severe cases of IBD.AimThis study aimed to assess the efficacy and safety of IFX and ADA in individuals diagnosed with moderate to severe IBD.MethodThis study is a prospective open-labeled randomized parallel study that included moderate to severe IBD patients treated with either IFX or ADA. A total of 56 patients participated, with 34 patients received IFX and 22 patients received ADA. Various measures, including Crohn’s Disease Activity Index (CDAI), Mayo Score/ Disease Activity Index (DAI), and C-reactive protein (CRP) levels, were taken at baseline and week 14 to assess the efficacy of the treatments. In addition, the levels of drugs and sTREM-1 were measured at 14 weeks. Patient safety was monitored throughout the study period.ResultsIn the group received IFX, there was a notable decrease in CDAI (P = 0.045), DAI (P = 0.026), and CRP (P = 0.023 for CD, and P = 0.021 for UC) levels. In addition, the group received ADA experienced a significant reduction in CDAI (P = 0.001), DAI (P = 0.032), and CRP (P < 0.018 for CD and P = 0.003 for UC) levels. Responders had higher drug concentrations than non-responders, notably IFX concentration was higher in responders with CD (P = 0.001) and UC (P < 0.001). ADA concentration was higher in UC (P <= 0.001) and all CD patients responded to the treatment. The same trend was observed for sTREM-1 levels in CD and UC patients (P = 0.042, and P = 0.015, respectively) in the IFX group. In UC patients treated with ADA, the level of sTREM-1 was significantly low (P = 0.002).ConclusionBoth IFX and ADA have a good safety profile and deliver a beneficial clinical and laboratory response in moderate-severe IBD patients.Clinical Trial RegistrationThis study is registered on ClinicalTrials.gov under the identifier NCT05291039. (You can access the study at https://clinicaltrials.gov/study/NCT05291039 (First Posted: March 22, 2022).

Population Pharmacokinetics of Adalimumab in Juvenile Idiopathic Arthritis Patients: A Retrospective Cohort Study Using Clinical Care Data.

Juvenile idiopathic arthritis (JIA) is a chronic autoimmune disorder that primarily affects the joints in children. Notably, it is known to co-occur with uveitis. Adalimumab, a monoclonal anti-TNF antibody, is effective in treating both conditions. A deeper understanding of the pharmacokinetics (PK) of adalimumab in JIA is crucial to advance in more personalized treatment approaches. The objective of this study is to evaluate the population PK profile of adalimumab in JIA and to explain causes for its variability. Adalimumab and antidrug antibody concentrations were retrospectively retrieved from the charts of patients with JIA. Initially, five literature-based population PK models of adalimumab were evaluated to assess their ability to describe the observed concentration-time profiles in the JIA cohort. These models included one specifically for the pediatric Crohn's disease population and four derived from studies in adult populations in healthy subjects and rheumatoid arthritis patients. Subsequently, a novel population PK model tailored to the JIA population was developed using NONMEM software. Monte Carlo simulations were then conducted utilizing the final PK model to visualize the concentration-time profile of adalimumab in patients with JIA and the impact of covariates. A cohort of 50 patients with JIA with 78 available adalimumab samples was assessed. The mean age was 11.8±3.9years, with a median body weight of 49kg (interquartile range 29.4-59.8kg). All literature models adequately described the concentration-time profiles in JIA. The best model, which was developed in patients with rheumatoid arthritis during the maintenance phase of treatment, served as a basis for estimating clearance in JIA, resulting in a value of 0.37L per day per 70kg. Patient body weight, antidrug antibodies, methotrexate use, CRP level, and comorbidity of uveitis were found to have a significant impact on adalimumab clearance, and these reduced the inter-patient variability from 58.6 to 28.0%. On steady state in the simulated patient population, the mean trough level was 7.4±5.5mg/L. The two dosing regimens of 20 and 40mg every other week, based on patients' body weight, resulted in comparable simulated overall drug exposure. Five literature models effectively described adalimumab PK in this pediatric cohort, highlighting the potential for extrapolating existing models to the pediatric population. The new JIA model confirmed the effect of several known covariates and found a novel association for drug clearance with methotrexate use (lower) and uveitis (higher), which might have clinical relevance for personalized dosing in JIA.

Live Rotavirus Vaccination Appears Low-risk in Infants Born to Mothers With Inflammatory Bowel Disease on Biologics

Biologic therapies in the context of inflammatory bowel disease and pregnancy lead to improved maternal and fetal outcomes. Placental transfer results in detectable drug concentrations in infants. Rotavirus infection results in diarrheal related hospitalizations; however, the live oral vaccine is not currently recommended in biologic exposed infants. The aim of this study was to assess the effect of maternal biologic therapies on the infant immune system and safety of live rotavirus vaccination in biologic-exposed infants. Biologic-exposed infants underwent standardized clinical assessments, drug concentration, and immune function testing (complete blood count, differential, immunoglobulin levels, extended B-cell and T-cell subset enumeration, Recent Thymic Emigrants, regulatory T-cell numbers, mitogen stimulation assays, and review of T-cell Receptor Excision Circles in the newborn screen). Rotavirus vaccine-specific adverse effects following immunizations up to 42 days post the last dose of the vaccine series were recorded. There were 57 infants born to 52 mothers with inflammatory bowel disease exposed to infliximab (n= 21), adalimumab (n= 19), vedolizumab (n= 10), and ustekinumab (n= 7) in the third trimester for a median of 39 weeks (interquartile range, 38-39 weeks) at delivery. Immunologic assessments validated for age were normal in all infants despite median infliximab concentrations of 6.1 ug/mL (range, 0.4-28.8 ug/mL), adalimumab concentrations of 1.7ug/mL (range, 0.7-7.9 ug/mL), ustekinumab concentrations of 0.6 ug/mL (range, 0-1.1), and undetectable for vedolizumab at 10.7 weeks (interquartile range, 9.4-12.4) of age. The live oral rotavirus vaccine series was provided to 50 infants with the first dose given at a median of 13weeks of age. No adverse effects following immunization were reported. Immune function testing was normal, and administration of live rotavirus vaccination appeared low-risk in biologic-exposed infants irrespective of circulating drug levels.

Higher Adalimumab Concentration Is Associated With Complete Fistula Healing in Patients With Perianal Fistulizing Crohn’s Disease

Perianal fistulas can develop in around 30% of patients with Crohn's disease (CD) and are associated with impaired quality of life and worse outcomes including increased rates of hospitalizations and surgeries.1 The cornerstone of pharmacologic treatment for perianal fistulizing CD is anti-tumor necrosis factor therapy, mainly infliximab and adalimumab (ADM).2 Therapeutic drug monitoring (TDM) can be used to identify potential pharmacokinetic and pharmacodynamic issues and avoid or manage unwanted outcomes, such as primary nonresponse and secondary loss of response.3 There are several exposure-response relationship data demonstrating a positive correlation between serum infliximab concentrations and favorable objective therapeutic outcomes in patients with perianal fistulizing CD.4 Nevertheless, there are only limited data, which is mostly from small retrospective studies regarding the association of ADM concentration and outcomes in patients with perianal fistulizing CD.4-8 Furthermore, the optimal ADM concentration for fistula healing still remains to be elucidated. This is clinically important because drug concentration cutoffs are used in reactive and proactive TDM algorithms to define therapeutic drug concentrations. This study investigates the association of maintenance ADM concentrations with complete fistula healing (CFH) and identifies an optimal ADM concentration threshold for CFH.

Observational Study to Compare Biological Drug Concentration Quantification Techniques and Immunogenicity in Patients with Immune-Mediated Diseases.

Measuring biological drugs' trough concentrations and the concentrations of anti-drug antibodies is a valuable practice for treatment optimization. ELISA techniques are the gold standard for biological drug concentration quantification, but new techniques such as chemiluminescence immunoassays present some advantages. The aim of this unicentric prospective observational study is to compare the infliximab, adalimumab, vedolizumab and ustekinumab trough levels and anti-adalimumab and anti-infliximab antibodies concentrations obtained when using a chemiluminescent instrument (i-TRACK®, Theradiag, Croissy-Beaubourg, France) and an ELISA instrument (TRITURUS®, Griffols, Barcelona, Spain). Linear regression, Pearson or Spearman tests, Bland-Altman plots and the Cohen kappa test were applied for every sample. The correlation was excellent for both assays in the measurement of all drug concentrations. In general, values were lower when measured using i-TRACK than when using TRITURUS, especially when the values were high. Both techniques proved valuable in clinical practice for monitoring adalimumab and infliximab drug concentration. However, the results were modest for ustekinumab and vedolizumab, so caution is recommended and further research is needed. The limited number of anti-drug antibody-positive samples precluded a comparison between the techniques.

Effect of adalimumab as an anti-inflammatory agent on gene expression of retinal pigment epithelial cells

Adalimumab (ADA) is an anti-inflammatory antibody that has FDA approval as a systemic medication for treating noninfectious uveitis. It is also provisionally being investigated as an intravitreal injection for various retinal conditions. This study aimed to assess the effect of ADA on apoptotic, inflammatory, and fibrogenesis gene expression at mRNA and protein levels in retinal pigment epithelial (RPE) cells. RPEs were treated with serial concentrations of ADA (0.5x, x, 2x, and 4x; [x = 250 µg/mL]) for 24 hours. MTT assay was done and the mRNA and protein expressions were quantified using real-time PCR and ELISA assay, respectively. The mRNA levels of IL-1b and IL-6 were significantly increased in ADA-treated RPEs at 0.5x and x concentrations. However, the increase in cytokine secretion was observed only in IL-1b at x concentration. TGF-β was significantly upregulated in the 0.5x and 4x doses of ADA both at mRNA and protein levels. MTT assay, along with an unchanged BCL-2/BAX ratio confirmed the safety of ADA on RPEs at all studied concentrations. In conclusion, despite its safety, the 2x concentration of ADA was the only dose that did not ignite the expression of any of the studied inflammatory and fibrogenesis genes. This dosage, which is roughly equal to 2 mg intravitreal dose in a clinical setting, might be referred to as a reference starting point for future in-vivo studies in ocular conditions.

Antibiotics influence the risk of anti-drug antibody formation during anti-TNF therapy in Chinese inflammatory bowel disease patients.

Aims: The formation of anti-drug antibodies (ADAs) during anti-tumor necrosis factor (anti-TNF) therapy is reported to lead to reducing serum drug levels, which may bring about a loss of response to treatment. Previous research has suggested an association between specific antibiotic classes and ADA formation during anti-TNF therapy. However, there are few studies specifically examining this association in Chinese inflammatory bowel disease (IBD) patients. Therefore, our study aimed to evaluate the possible effect of antibiotic use on ADA formation to anti-TNF therapy in Chinese patients with IBD. Methods: A total of 166 patients with IBD, including 149 with Crohn's disease (CD) and 17 with ulcerative colitis (UC), were included in this retrospective analysis. These patients were initially treated with anti-TNF therapy (infliximab or adalimumab) after January 2018 and reviewed with available ADA levels before October 2023. After univariable analysis of all the variables, a multivariate Cox proportional hazards model was used to assess the association between antibiotic use and ADA development. Results: Among 166 IBD patients treated with infliximab (108/166, 65.1%) or adalimumab (58/166, 34.9%), 31 patients (18.7%) were measured as positive ADA levels. Cox proportional hazard model demonstrated an increased risk of ADA formation in IBD patients who used β-lactam-β-lactamase inhibitor combinations (BL-BLIs) (HR = 5.143, 95%CI 1.136-23.270, p = 0.033), or nitroimidazoles (HR = 4.635, 95%CI 1.641-13.089, p = 0.004) during 12months before the ADA test. On the contrary, a reduced risk was noted in patients treated with fluoroquinolones (HR = 0.258, 95% CI 0.072-0.924, p = 0.037). Moreover, the median serum infliximab or adalimumab concentration in patients with positive ADA levels was significantly lower than that in patients with negative ADA levels (infliximab: 0.30 vs. 1.85μg/mL, p < 0.0001; adalimumab: 0.45 vs. 7.55μg/mL, p = 0.0121). Conclusion: ADA development is associated with various antibiotic classes. BL-BLIs and nitroimidazoles might increase the risk of ADA formation during anti-TNF therapy in Chinese IBD patients, while the treatment with fluoroquinolones could probably reduce such risk. There were certain limitations in the retrospective analysis of the study, therefore, the results are just for reference, and other studies are needed to further confirm our findings.

Development and Validation of the Cell-based Functional Method for Neutralizing Anti-adalimumab Antibodies Detection in Human Serum

Introduction. Adalimumab, a fully humanized monoclonal antibody, is a tumor necrosis factor (TNFα) inactivator that is used against a number of autoimmune diseases such as rheumatoid arthritis and other most common inflammatory arthropathies (ankylosing spondylitis, psoriatic arthritis). Despite the proven efficacy of adalimumab treatment, there is a risk of adverse events, tied up with the formation of anti-drug antibodies, including neutralizing antibodies. Currently, the evaluation and characterization of neutralizing antibodies has become an important part of clinical trials in the development of new drugs and biosimilars.Aim. The aim of this study is to develop and validate the cell-based functional method for neutralizing anti-adalimumab antibodies determination in human serum.Materials and methods. For determination of neutralizing anti-adalimumab antibodies, the cell line L-929 has been employed. L-929 is a cell line sensitive to the TNFα-mediated apoptosis; the neutralizing antibodies interact with adalimumab that leads to TNFα-mediated cytotoxicity. Cytotoxicity was measured using resazurin, an aromatic compound that is a redox indicator.Results and discussion. The developed method was validated for cut point, selectivity, sensitivity, precision, specificity and stability (short- and long-term). An important part of a method development for determining neutralizing antibodies is the selection of concentrations of TNFα (4 ng/ml) and adalimumab (250 ng/ml), as well as determining the minimum required dilution – this parameter is established as 1 : 20. Cut point was chosen as a «floating» cut point, and a correction factor (normalization factor) was determined equal to 0,86. The sensitivity of the developed method was estimated at 108,9 ng/ml of neutralizing anti-adalimumab antibodies.Conclusion. The obtained results can be applied for determining anti-adalimumab neutralizing antibodies in the assessment of the adalimumab immunogenicity, including clinical trials.

Prospective study to characterize adalimumab exposure in pediatric patients with rheumatic diseases

BackgroundIn pediatric rheumatic diseases (PRD), adalimumab is dosed using fixed weight-based bands irrespective of methotrexate co-treatment, disease activity (DA) or other factors that might influence adalimumab pharmacokinetics (PK). In rheumatoid arthritis (RA) adalimumab exposure between 2–8 mg/L is associated with clinical response. PRD data on adalimumab is scarce. Therefore, this study aimed to analyze adalimumab PK and its variability in PRD treated with/without methotrexate.MethodsA two-center prospective study in PRD patients aged 2–18 years treated with adalimumab and methotrexate (GA-M) or adalimumab alone (GA) for ≥ 12 weeks was performed. Adalimumab concentrations were collected 1–9 (maximum concentration; Cmax), and 10–14 days (minimum concentration; Cmin) during ≥ 12 weeks following adalimumab start. Concentrations were analyzed with enzyme-linked immunosorbent assay (lower limit of quantification: 0.5 mg/L). Log-normalized Cmin were compared between GA-M and GA using a standard t-test.ResultsTwenty-eight patients (14 per group), diagnosed with juvenile idiopathic arthritis (71.4%), non-infectious uveitis (25%) or chronic recurrent multifocal osteomyelitis (3.6%) completed the study. GA-M included more females (71.4%; GA 35.7%, p = 0.13). At first study visit, children in GA-M had a slightly longer exposure to adalimumab (17.8 months [IQR 9.6, 21.6]) compared to GA (15.8 months [IQR 8.5, 30.8], p = 0.8). Adalimumab dosing was similar between both groups (median dose 40 mg every 14 days) and observed DA was low. Children in GA-M had a 27% higher median overall exposure compared to GA, although median Cmin adalimumab values were statistically not different (p = 0.3). Cmin values ≥ 8 mg/L (upper limit RA) were more frequently observed in GA-M versus GA (79% versus 64%). Overall, a wide range of Cmin values was observed in PRD (0.5 to 26 mg/L).ConclusionThis study revealed a high heterogeneity in adalimumab exposure in PRD. Adalimumab exposure tended to be higher with methotrexate co-treatment compared to adalimumab monotherapy although differences were not statistically significant. Most children showed adalimumab exposure exceeding those reported for RA with clinical response, particularly with methotrexate co-treatment. This highlights the need of further investigations to establish model-based personalized treatment strategies in PRD to avoid under- and overexposure.Trial registrationNCT04042792, registered 02.08.2019.

Development and validation of a novel therapeutic drug monitoring-based nomogram for prediction of primary endoscopic response to anti-TNF therapy in active Crohn's disease.

Anti-tumor necrosis factor (TNF) monoclonal antibodies, especially infliximab (IFX) and adalimumab (ADA), are considered the first-line treatment for active Crohn's disease (CD). However, the predictive role of therapeutic drug monitoring (TDM) of serum anti-TNF in monitoring the treatment of inflammatory bowel disease (IBD) remains controversial. To explore the correlation between serum anti-TNF levels and early endoscopic response in active CD using a TDM-based nomogram. Cross-sectional study. The simplified endoscopic activity score for CD (SES-CD), Crohn's disease activity index (CDAI), laboratory parameters, and the serum trough levels of IFX and ADA were assessed. The trough levels of IFX or ADA were significantly higher in patients with endoscopic response compared to non-responders in the development cohort (p < 0.001). The IFX and ADA levels showed a weak but significantly negative correlation with SES-CD (p < 0.001), CDAI (p < 0.001), and C-reactive protein (CRP) (p < 0.001) at week 14 post-IFX therapy in the development cohort. Furthermore, the receiver operating characteristic curve revealed that an optimal level of IFX (4.80 μg/mL) and ADA (8.80 μg/mL) exhibited the best performance in predicting endoscopic response. Concomitantly, we developed a novel nomogram prediction model based on the results of multivariate logistic regression analysis, which consisted of CRP, albumin (Alb), and anti-TNF trough levels at week 14. The nomogram showed significant discrimination and calibration for both IFX and ADA in the development cohort and performed well in the external validation cohort. This study demonstrates a robust association between serum concentrations of IFX, ADA, Alb, and CRP and primary endoscopic response in active CD patients. Importantly, the TDM- and laboratory marker-based nomogram may be used to evaluate the primary endoscopic response to anti-TNF therapy, especially for optimizing treatment strategies and switching therapy in CD patients.

Monitoring Adalimumab concentration, Adalimumab antibodies, fecal calprotectin, and QuantiFERON test positivity in patients with inflammatory bowel disease

&amp;lt;p&amp;gt;&amp;lt;strong&amp;gt;Introduction.&amp;lt;/strong&amp;gt; Inflammatory bowel diseases (IBD) are a serious global health problem affecting mostly younger and middle-aged persons. Despite the availability of variety of treatment approaches, the disease often progresses unpredictably. Biological drugs offer hope for IBD treatment. Our research share our preliminary findings regarding the monitoring of adalimumab (ADM) and adalimumab antibodies (ADA) concentrations, fecal calprotectin levels, and the frequency of QuantiFERON test positivity in IBD patients treated with biological drugs.&amp;lt;strong&amp;gt; &amp;lt;/strong&amp;gt;&amp;lt;/p&amp;gt; &amp;lt;p&amp;gt;&amp;lt;strong&amp;gt;Methods.&amp;lt;/strong&amp;gt; The study was designed as a retrospective, descriptive, single-center study and was conducted at the University Clinical Center of the Republic of Srpska, Banja Luka, from January 2018 to June 2022. Medical records of patients treated at the Internal Medicine Clinic were analyzed. Patients were categorized based on underlying disease and duration of biological therapy. ADM and ADA concentrations were monitored at intervals, and QuantiFERON test positivity and fecal calprotectin levels were recorded. Statistical methods, including analysis of Variance (ANOVA) and paired t-test were performed using the SPSS program version 29.&amp;lt;/p&amp;gt; &amp;lt;p&amp;gt;&amp;lt;strong&amp;gt;Results.&amp;lt;/strong&amp;gt; Medical records of 117 patients were analyzed. Most of them, 44 were treated with adalimumab. Male patients were predominant (59.10%) in our study over females. Patients were also categorized based on the length of biological therapy. ADM and ADA concentrations increased with time (after 6, 12, 18 and 24 months), but without statistical significance. Fecal calprotectin levels decreased after 12 and 24 months of treatment. Out of the total number of patients, 53.83% of QuantiFERON positive patients were treated with adalimumab. Prophylactic isoniazid therapy was carried out in 63.6% of patients.&amp;lt;/p&amp;gt; &amp;lt;p&amp;gt;&amp;lt;strong&amp;gt;Conclusion. &amp;lt;/strong&amp;gt;Our initial experience in monitoring biological drug concentrations and fecal calprotectin levels in IBD patients showed a decrease in fecal calprotectin levels and an increase in ADM and ADA concentrations over time but there were no statistically significant differences.&amp;lt;/p&amp;gt;

Defining a therapeutic range for adalimumab serum concentrations in the management of pediatric noninfectious uveitis, a step towards personalized treatment

Background Adalimumab is currently considered the most efficacious anti-TNFα agent for childhood noninfectious uveitis (NIU). The objective of this study was to define a therapeutic range for adalimumab trough levels in the treatment of childhood NIU.MethodsA retrospective, observational, pilot study of 36 children with NIU aged < 18 years, treated with adalimumab. Serum adalimumab through levels and adalimumab anti-drug antibodies (ADA) were analysed at least 24 weeks after start adalimumab.ResultsAdalimumab trough levels were significantly higher in complete responders 11.8 μg/mL (range 6.9–33.0) compared to partial or non-responders 9,2 μg/mL (range 0–13.6) (p = 0,004). Receiver–operator characteristics analyses with an area under the curve of 0,749 (95% CI, 0,561–0,937) defined 9.6 µg/mL as the lower margin for the therapeutic range. This cut-off corresponds with a sensitivity of 88% and a specificity of 56% (positive predictive value, 85%; negative predictive value, 62.5%). A concentration effect curve defined 13 µg/mL as the upper margin. Approximately one-third (30.5%) of patients had an adalimumab trough concentration exceeding 13 µg/mL. Free ADA were observed in 2 patients (5.5%).ConclusionsA therapeutic range of adalimumab trough levels of 9.6 to 13 µg/mL, which corresponds with an optimal clinical effect, was identified. Therapeutic drug monitoring may guide the optimisation of treatment efficacy in children with NIU in the treat-to-target era.

Quantifying the Effect of Methotrexate on Adalimumab Response in Psoriasis by Pharmacokinetic–Pharmacodynamic Modeling

Previously, we showed that the combination of methotrexate and adalimumab treatment leads to less antidrug antibody development. In this study, we quantify the pharmacokinetics/pharmacodynamics (PK/PD) of adalimumab and evaluate the influence of methotrexate cotreatment. A population PK-PD model was developed using prospective data from 59 patients with psoriasis (baseline PASI= 12.6) receiving adalimumab over 49 weeks. Typical PK and PD parameters and their corresponding interpatient variability were estimated. We performed a covariate analysis to assess whether interpatient variability could be explained by addition of methotrexate and other covariates. In total, 330 PASIs, 252 adalimumab serum concentrations, and 247 antidrug antibody titers were available. Presence of antidrug antibodies (adalimumab group= 46.7%, adalimumab+ methotrexate group= 38.7%; P= .031) was correlated with increased adalimumab apparent clearance (P < .001). In the PD model, the use of concomitant methotrexate was borderline to significantly correlated with a decreased half-maximal inhibitory concentration (adalimumab concentration for which clinical response score is reduced by half; P < .10). On the basis of our PK-PD model, concomitant use of methotrexate indirectly increases adalimumab concentration, partially through less antidrug antibodies formation, which may result in better efficacy.

Retrospective Assessment of an Adalimumab Model-Informed Precision Dosing Support Tool for Use in Pediatric Inflammatory Bowel Disease.

Therapeutic drug monitoring in pediatric inflammatory bowel disease (IBD) has been used to achieve and maintain remission. Few guidelines exist to aid clinicians in the adjustment of anti-tumor necrosis factor therapies. The objective was to assess the agreement between real-world postinduction and posteriori analysis of retrospective data, using 2 novel pharmacokinetic (PK) models for adalimumab. A retrospective chart review was conducted in pediatric IBD patients treated with adalimumab. A Bayesian clinical decision support tool (InsightRX) was used. Postinduction serum concentration measurements of adalimumab were performed by drug-tolerant, homogenous shift mobility assay. Predicted serum adalimumab concentrations from both models were compared to the actual serum concentrations through a Bland-Altman analysis. Paired sample t test was used for equivalence. A total of 47 patients were included. Forty-one patients (87%) had Crohn disease, and 30 (64%) were male. Most were induced with 160 mg of adalimumab and maintained on 40 mg biweekly. No significant difference resulted between the de Klaver average prediction and mean population concentration (p = 0.294). Significant difference was observed between Ternant and mean population serum adalimumab concentration (p < 0.001). The Bland-Altman plot for the de Klaver method showed no proportional bias. Additionally, 49% of patients required a dose adjustment during maintenance therapy. The de Klaver model was able to provide less bias than the Ternant model and may aid in predicting serum adalimumab concentrations. Approximately half of the patients required dose adjustment during maintenance therapy to obtain a therapeutic drug concentration or achieve clinical remission.

Higher Adalimumab Trough Levels Are Associated with Histologic Remission and Mucosal Healing in Inflammatory Bowel Disease.

(1) Many patients with inflammatory bowel disease (IBD) in endoscopic remission have persistent histologic activity, which is associated with worse outcomes. There are limited data on the association between adalimumab drug concentrations and histologic outcomes using validated histologic indices. We aimed to assess the relationship between adalimumab concentrations and the Robarts Histopathology Index (RHI). (2) Patients from a tertiary IBD center from 2013 to 2020 with serum adalimumab (ADA) trough concentrations measured during maintenance therapy (≥14 weeks) and a colonoscopy or flexible sigmoidoscopy with biopsies performed within 90 days of drug level were included. Blinded histologic scoring using the RHI was performed. Primary analysis assessed the relationship between adalimumab drug concentrations and histologic remission using receiver operating characteristic curve analysis. (3) In 36 patients (26 Crohn's Disease, 9 ulcerative colitis, 1 indeterminate), median adalimumab concentrations were higher (17.3 ug/mL, 12.2-24.0) in patients with histologic remission compared to those without (10.3 ug/mL, 6.8-13.9, p = 0.008). The optimal ADA concentration identified using the Youden threshold was ≥16.3 ug/mL (sensitivity 70%, specificity 90%). Patients with ADA ≥ 16.3 ug/mL had higher histologic remission rates (78%) compared to lower ADA concentrations (14%, p= 0.002), as well as higher mucosal healing rates (86%) compared to lower levels (12%, p = 0.001). Symptoms correlated weakly and non-significantly with both histologic (RHI) scores (r = 0.25, p = 0.2) and adalimumab concentrations (r = 0.05, p = 0.8). (4) The current study demonstrated that higher serum adalimumab concentrations (≥16.3 ug/mL) are needed for histologic remission and mucosal healing assessed using the RHI.

Serum levels of infliximab and adalimumab are associated with deep remission in inflammatory bowel disease

ObjectiveDeep remission defined by clinical-biomarker remission and mucosal healing has emerged as a new therapeutic target in inflammatory bowel disease. The aim of this study was to define an optimal cut-off concentration for infliximab and adalimumab during maintenance therapy associated with deep remission. The secondary objective, was to evaluate the influence of variables on anti tumor necrosis factor-alpha concentrations and deep remission. MethodRetrospective study including 120 and 122 patients inflammatory bowel disease diagnosed who received maintenance therapy with infliximab and adalimumab. Biomarker remission was considered by C-reactive protein < 5 mg/L and fecal calprotectin < 100 µg/g. Crohn's disease clinical remission was defined by a Harvey Bradshaw score < 5 and mucosal healing by a simple endoscopic score for Crohn's disease< 3. In ulcerative colitis, it was defined as a Mayo total score < 3 and Mayo endoscopic subscore < 2. Receiver operating characteristic test was performed to determine drug concentration thresholds associated with deep remission. Anti tumor necrosis factor-alpha concentrations were classified into quartiles. X2 and Kruskal-Wallis test were used to compare discrete and continuous variables between quartile groups. Multivariate logistic regression was performed to identify patient characteristics and serological facto C-reactive protein rs associated with deep remission. ResultsAnti tumor necrosis factor-alpha concentrations were higher in patients with deep remission, in infliximab (4.4, interquartile range: 3.3-6.5 vs 2.3, interquartile range: 1.1-4.2 µg/mL, P < 0.005) and adalimumab (6.3, interquartile range: 4.2-8.2 vs 3.9, interquartile range: 2.4-5.5 µg/mL, P < 0.005). A Receiver operating characteristic test identified a concentration threshold of 3.1 µg/mL in infliximab (area under the Receiver operating characteristic test curve, 0.72) and 6.3 µg/mL in adalimumab (area under receiver operating characteristic test curve, 0.75) associated with deep remission. Factors associated with the highest quartiles of serum infliximab concentration were: elevated body mass index, absence of previous inflammatory bowel disease-surgery, C-reactive protein < 5 mg/L, and fecal calprotectin < 100 µg/g. In adalimumab, higher quartiles were related to concomitant immunosuppressants, low body mass index, absence of previous inflammatory bowel disease-surgery, and C-reactive protein < 5 mg/L and fecal calprotectin < 100 µg/g. Multivariate regression identified fecal calprotectin < 100 µg/g, C-reactive protein < 5 mg/L, infliximab > 3.1 µg/mL and adalimumab concentrations > 6.3 µg/mL as factors significantly associated with deep remission. ConclusionsTrough infliximab and adalimumab concentrations, C-reactive protein < 5 mg/L and fecal calprotectin < 100 µg/g are associated with deep remission during maintenance therapy. Cutoff point of 3.1 and 6.3 g/mL for infliximab and adalimumab respectively, were identified as deep remission predictors.