Anti-adalimumab Antibodies in Patients with Non-infectious Ocular Inflammatory Disease: A Case Series.

PURPOSE: To report the clinical course of patients with ocular inflammatory disease treated with adalimumab in whom anti-adalimumab antibodies (AAA) were detected. METHODS: Single center case series. RESULTS: Eight patients with initial response to adalimumab developed a disease flare associated with positive AAA testing after 5 to 76 months of therapy. Six patients were receiving no concurrent antimetabolite therapy at the time of AAA diagnosis and four had a temporary lapse in adalimumab therapy prior to AAA discovery. AAA resulted in undetectable drug levels in five of the seven patients for whom data were available, and adalimumab was discontinued in six of the eight patients. Of two patients continued on adalimumab, one maintained detectable serum adalimumab despite AAA and one had a low AAA titer. CONCLUSIONS: For patients receiving adalimumab for ocular inflammatory disease, a disease flare in the setting of previously well-controlled disease should prompt consideration of AAA testing.

Comparison of a new rapid method for determination of serum anti-adalimumab and anti-infliximab antibodies with two established ELISA kits.

BACKGROUND: Adalimumab (ADL), infliximab (IFX) and their biosimilars are widely used biological drugs. Some patients, however, generate neutralizing antibodies that hamper the effectiveness of these drugs. Evidence shows therapeutic drug monitoring of serum levels ADL/IFX and anti-drug antibodies (ADA) is useful to improve treatment effectiveness. We evaluated a new rapid quantitative method, Quantum Blue (QB), for determining serum anti-ADL and anti-IFX antibodies (Research Use Only labelling) by comparing it with two established ELISA kits, Promonitor (PM) and Lisa-Tracker (LT). METHODS: Eighty samples (40 for each drug type) were analysed. Percentage of agreement and kappa statistic were used to compare positive/negative ADA results. Clinical implications for drug treatment in the patients with discordant results were evaluated. The Chi-square test was used to analyze differences for ADA detection in patients with disease flare and without concomitant immunosuppressant treatment. RESULTS: Agreement exceeded 80 % among anti-ADL methods. Although LT ELISA showed a lower capacity in detecting anti-ADL antibodies, discrepancies were found for levels close to the cut-off concentration, thus having minimal impact on clinical decisions. Conversely, QB anti-IFX displayed low agreement with PM and LT ELISA kits (67.5 % and 50 %, respectively), and was unable to detect high levels of antibodies, therefore having major clinical implications. Agreement between PM and LT ELISA anti-IFX kits was 82.5 % with all discordant results being undetected for PM and slightly positive for LT. CONCLUSION: QB anti-ADL shows similar performance to ELISA kits while QB anti-IFX needs further improvements to achieve reliable antibody detection.

No Difference of Adalimumab Pharmacokinetics When Dosed at 40 mg Every Week or 80 mg Every Other Week in IBD Patients in Clinical Remission After Adalimumab Dose Intensification.

INTRODUCTION: The pharmacokinetic equivalence of dose intensification with adalimumab (ADA) 80 mg every other week (EOW) compared to weekly 40 mg has only been supported by modeling systems. AIM OF THE STUDY: To compare the trough levels of ADA (TLA) and the occurrence of anti-ADA antibodies (AAA) between these two treatment regimens. PATIENTS AND METHODS: This was a prospective study including all consecutive patients with inflammatory bowel disease (IBD) who had reached a longstanding and deep remission under treatment with ADA 40 mg once a week. In these patients, the ADA regimen was changed from 40 mg/week to 80 mg EOW. TLA and AAA levels using a drug-tolerant assay were monitored before and ten weeks after from the change in the ADA regimen and the results compared by a Wilcoxon paired test. RESULTS: Sixty-two patients (60% CD, mean age 35 years) were included. Before and ten weeks after the changes of ADA regimen, the median TLA were (6.9 µg/mL versus 7.0 µg/mL, respectively; P = 0.34) and the AAA levels (3.4 µg/ml-eq versus 3.0 µg/ml-eq, respectively; P = 0.25.) were quite similar. Likewise, quartiles of TLA (Kendall test r = 0.91; P < 0.001) and AAA (r = 0.78; P < 0.001) did not differ before and after ADA regimen. When stratifying all the patients into 4 groups based on drug/antibody levels (immunogenic, subtherapeutic, therapeutic, or supratherapeutic), no patient needed for returning to the previous weekly regimen. In terms of acceptability, more than 60% of patients preferred an injection EOW compared once a week. CONCLUSIONS: In IBD patients who achieved a deep clinical remission under ADA 40 mg once a week, the pharmacokinetic of ADA was similar when ADA regimen was changed to 80 mg EOW. Given the patient's preference for the latter regimen, a modification of injection regimen should be systematically proposed.

¿Is seropositivity in patients with rheumatoid arthritis treated with adalimumab a factor to develop anti-adalimumab antibodies? / ¿Es la seropositividad en pacientes con artritis reumatoide tratados con adalimumab un factor para desarrollar anticuerpos anti-adalimumab?

ABSTRACT Objective: To determine whether seropositivity in rheumatoid arthritis patients treated with adalimumab (ADL) is associated with the presence of anti-adalimumab (anti-ADL) antibodies. Materials and methods: A descriptive observational study that included patients diagnosed with rheumatoid arthritis according to ACR 1987 criteria, and who were on treatment with ADL as the first biological, for at least six months. All patients were evaluated for rheumatoid factor, anti-citrulline antibodies, erythrocyte sedimentation rate, C-reactive protein, clinimetric indices, and level of anti-ADL antibodies. Results: A total of 80 patients with a mean age of 56 years were evaluated, of whom 86% were women. The mean duration of the disease was 15 years, and the ADL exposure time was 52 months (median value). The seropositivity for rheumatoid factor tended to be higher in patients who developed anti-ADL antibodies compared to those who did not (90.5% vs. 66.1%). The magnitude of the association between rheumatoid factor and the presence of anti-ADL antibodies was shown to be strong and statistically significant (OR = 4.87, 95% CI; 1.03-23.03). Adjusted multivariate regression analyses showed a strong association (OR = 9.77, 95% CI; 1.74-54.79) between seropositivity and the presence of anti-ADL antibodies, which, given the low number of patients, lacks precision (95% CI very wide). Conclusions: Seropositive patients tend to have more anti-ADL antibodies. However, a larger sample size is required to obtain the necessary precision and greater certainty in these findings.

RESUMEN Objetivo: Determinar si la seropositividad en pacientes con artritis reumatoide tratados con adalimumab (ADL), se asocia a la presencia de anticuerpos anti-adalimumab (anti-ADL). Materiales y métodos: Es un estudio observacional descriptivo que incluyó pacientes con diagnóstico de artritis reumatoide según criterios ACR1987, que estaban en tratamiento con ADL como primer biológico, por al menos 6 meses. Todos los pacientes se evaluaron para factor reumatoide, anticuerpos anticitrulina, velocidad de sedimentación globular, proteína C reactiva, índices clinimétricos y nivel de anticuerpos anti-ADL. Resultados: Se evaluaron 80 pacientes con edad promedio de 56 arios, el 86% fueron mujeres, la duración promedio de la enfermedad fue de 15 años y el tiempo de exposición a ADL de 52 meses (valor mediano). La seropositividad para factor reumatoide tendió a ser mayor en los pacientes que desarrollaron anticuerpos anti-ADL en comparación con los que no (90,5% vs. 66,1%). La magnitud de la asociación entre factor reumatoide y la presencia de anticuerpos anti-ADL tendió a ser fuerte y estadísticamente significativa (OR = 4,87; IC 95%: 1,03-23,03). Los análisis ajustados de regresión multivariable mostraron una asociación fuerte (OR = 9,77; IC 95%: 1,74-54,79) entre la seropositividad y la presencia de anticuerpos anti-ADL, que dado el bajo número de pacientes carece de precisión (IC 95% muy amplios). Conclusiones: Los pacientes seropositivos tienden a presentar más anticuerpos anti-ADL; sin embargo, se requiere tener un mayor tamaño muestral para obtener la precisión necesaria y tener mayor certeza en estos hallazgos.

Clinically important neutralizing anti-drug antibodies detected with an in-house competitive ELISA.

Therapeutic drug monitoring of TNF-alpha inhibitors is crucial for evaluating patients with inflammatory diseases on a personalized level. It has been clinically observed that many patients receiving TNF-alpha inhibitors, with negative drug and anti-drug antibody results from bridging ELISA (bELISA), lose their drug response over time, despite dose optimization. Our aims were to develop innovative in-house competitive ELISAs (cELISAs) for the detection of neutralizing antibodies against infliximab and adalimumab and compare their results to reporter gene assay (RGA) and in-house bELISA. Furthermore, we aimed to evaluate patient anti-drug antibody results in regard to their clinical records and potential benefits of therapeutic drug monitoring with the novel cELISAs. Sera of patients treated with infliximab (n = 46) or adalimumab (n = 31), having undetectable drug levels, were tested with our in-house cELISA. Briefly, samples were incubated with a fixed amount of drug and the neutralizing capacity of the samples was determined. The cELISA results were compared to RGA and bELISA results using Spearman's correlation coefficient. Additionally, patient clinical data were evaluated in line with the results of cELISA, bELISA, and RGA using the Kaplan-Meier analysis and the Log Rank test. Both anti-infliximab and anti-adalimumab cELISAs showed very good correlation to RGA (r = 0.932, p < 0.0001 and r = 0.947, p < 0.0001, respectively). Furthermore, a positive result in anti-infliximab cELISA can predict treatment failure in 100% of patients with negative bELISA, while a positive result in anti-adalimumab cELISA can predict treatment failure in 80% of patients with negative bELISA. Taken together, we developed innovative cELISAs enabling quantification of functional and neutralizing anti-drug antibodies, comparable to RGA. The association between cELISA results and loss of drug response in patients identified clinically important anti-drug antibodies, as measured by cELISA.

Is the Pharmacokinetic Profile of a First Anti-TNF Predictive of the Clinical Outcome and Pharmacokinetics of a Second Anti-TNF?

AIM: The aim of this study was to evaluate prospectively the clinical outcomes and pharmacokinetics of a second anti-TNF according to the pharmacokinetics of the first anti-TNF in patients with inflammatory bowel disease (IBD). METHODS: In patients in loss of response (LOR) to a first optimized anti-TNF and switched to a second anti-TNF, pharmacokinetics of anti-TNF were measured at the switch time, 30 weeks later, at the time of LOR, or at the end of the study (102 weeks). RESULTS: At the switch time, patients (n = 59) belonged to 4 groups according to the pharmacokinetics of the first anti-TNF: group 1 (n = 18), therapeutic trough levels; group 2 (n = 13) undetectable trough levels with antibodies against anti-TNF; group 3 (n = 13) without antibodies against anti-TNF; and group 4 (n = 15) subtherapeutic trough levels. After switching, the failure rates at week 30 and during the follow-up were as follows, respectively: in group 1 with therapeutic levels, 50% and 78%, despite therapeutic levels of the second anti-TNF in 83% of cases; in group 2 with undetectable levels and antibodies, 15% and 69% with undetectable levels of the second anti-TNF and antibodies in 85% of cases; in group 3 with undetectable levels without antibodies, 0% and 31% with therapeutic levels in 77% of cases; in group 4 with subtherapeutic levels, 13% and 33% with therapeutic levels in 73% of cases. Clinical remission rates were significantly lower (P ≤ 0.05) in groups 1 and 2 with therapeutic or undetectable levels with antibodies than in the 2 other groups. CONCLUSION: In the case of LOR with therapeutic levels of the first anti-TNF or undetectable levels with antibodies, the switch to a second anti-TNF results in pharmacokinetic profile similar to the first one and again in LOR in most of the patients.

Association between serum adalimumab concentrations and endoscopic disease activity in patients with Crohn's disease.

BACKGROUND AND AIMS: The serum trough level of adalimumab (ADA) associated with mucosal healing (MH) remains unclear. Our objective was to determine the association between ADA trough levels and the endoscopic activity in Crohn's disease. MATERIALS AND METHODS: This was a cross-sectional study including 42 patients with Crohn's disease. Endoscopic activity was assessed using the modified Rutgeerts scoring system. The primary outcome was mucosal healing, and the secondary outcomes were serum levels of C-reactive protein and albumin. RESULTS: Endoscopic disease activity negatively correlated with serum ADA trough levels (Spearman's rank correlation coefficient (ρ) = -0.42, P < 0.01). MH was achieved in 14 of 42 patients (33.3%). Serum ADA trough levels were significantly higher in the MH group than in the no-MH group (ADA mean trough level, 11.7 vs 7.5 µg/mL). The proportion of patients with ADA as the first biologic was significantly higher in the MH group than in the no-MH group (85.7% vs 53.5%, P = 0.04). The ADA trough levels that were best associated with normal C-reactive protein and albumin levels were 5.57 µg/mL (odds ratio [OR] 16.0, specificity 0.80) and 6.95 µg/mL (OR 9.2, specificity 0.81), respectively. The ADA trough level that was best associated with MH was 7.9 µg/mL (OR 13.5, specificity 0.86). The endoscopic disease activity was significantly higher in the patients with ADA as the second biologic as compared with those with ADA as the first biologic (P < 0.05). CONCLUSION: Mucosal healing requires higher ADA trough levels, compared with those required to normalization of routine clinical markers.

The clinical relevance of early anti-adalimumab antibodies detection in rheumatoid arthritis, ankylosing spondylitis and psoriatic arthritis: A prospective multicentre study.

OBJECTIVES: To evaluate the relevance of anti-adalimumab (anti-ADA) antibodies (Abs) and their relationship with clinical/laboratory features in rheumatoid arthritis (RA), ankylosing spondylitis (AS) and psoriatic arthritis (PsA). METHODS: Fifty-eight patients affected with RA, AS and PsA were prospectively enrolled. Clinical/laboratory characteristics, disease activity, anti-ADA, anti-nuclear (ANA), anti-double strand (ds)DNA, anti-extractable nuclear antigens (anti-ENA) and anti-phospholipid Abs (aPL) were evaluated at baseline, 4, 12 and 24 weeks of adalimumab treatment. RESULTS: Anti-ADA Abs were observed in 11/58 (19%) patients; they were detected within the 4th week of therapy in 90.9% of the positive subjects. Anti-ADA positivity was associated with significantly lower mean adalimumab serum levels (P<0.05). Treatment failure was observed in 20/58 (34.5%) patients and was significantly associated with anti-ADA Abs (P<0.05). Mean adalimumab serum levels were significantly lower in patients with treatment failure than in the responders one, both in the whole cohort (P<0.01) and in the group of anti-ADA positive patients (P<0.01). Adverse events happened more often in anti-ADA positive then in anti-ADA negative patients (27.3% vs 14.9%). CONCLUSIONS: Anti-ADA abs could be considered an early marker associated to a poor clinical response to adalimumab treatment. Routine ANA/anti-ENA/aPL monitoring did not reveal as useful tools to predict the development of anti-ADA abs.

Comparative study of both versions of an immunoassay commercialized for therapeutic drug monitoring of adalimumab in rheumatoid arthritis.

OBJECTIVE: To describe the results of the comparative study between both versions of an immunoassay commercialized for therapeutic drug monitoring of adalimumab (ADA) in rheumatoid arthritis (AR). MATERIAL AND METHODS: 140 samples of patients with RA treated with ADA 40mg every 14 days were analyzed by both versions of the test (V1 or previous and V2 or updated). RESULTS: A good correlation was obtained by both versions. In general V2 provides higher results of ADA's concentration than V1 and presents greater precision in the range of concentrations for clinical decisions, adjusting for the real concentration of the drug in blood. In addition, V2 allows for complete automation, which simplifies the analysis and reduces significantly the variability. CONCLUSION: ADA's monitoring with the updated version demonstrated to have technical significant advantages, constituting a more practical tool for therapeutic decisions in patients with RA.