High BMI is associated with lower TNF-α inhibitor serum trough levels and higher disease activity in patients with axial spondyloarthritis.

BACKGROUND: TNF-α inhibitor (TNFi) serum trough levels have previously been found to be related to disease activity in axial spondyloarthritis (axSpA). However, most research regarding serum trough levels has been conducted in patients who only recently started TNFi therapy. Therefore, our objective was to explore TNFi serum trough level measurements in relation to disease activity and BMI in the total axSpA population in daily clinical practice, also including patients on long-term TNFi therapy. METHODS: Consecutive patients from the Groningen Leeuwarden Axial Spondyloarthritis (GLAS) cohort were approached for a TNFi serum trough level measurement during their regular outpatient visit at the UMCG. Spearman's correlation coefficient was used to analyse the relation of serum trough levels with disease activity and BMI. Logistic regression was performed to analyse the relation between therapeutic drug levels and disease activity, corrected for potential confounders, including BMI. RESULTS: Thirty-four patients on adalimumab and 21 patients on etanercept were included. Mean age was 45 ± 12 years, 47% were male, median BMI was 26.4 (IQR 23.9-32.5) and median treatment duration was 41 months (range 2-126). According to definitions of Sanquin, 47% of patients had therapeutic serum trough levels. No significant correlations were found between TNFi levels and disease activity (ASDAS-CRP: adalimumab: ρ = -0.16, p = 0.39; etanercept: ρ = -0.29, p = 0.20). TNFi levels were moderately correlated with BMI (adalimumab: ρ = -0.48, p = 0.004; etanercept: ρ = -0.50, p = 0.021). Patients with active disease (ASDAS ≥ 2.1) showed higher BMI than patients with inactive disease (median 29.7 vs. 24.6, p = 0.015). In multivariable regression analyses, BMI was identified as the only confounder for the relationship between therapeutic drug levels and ASDAS. CONCLUSION: In this cross-sectional, observational study of axSpA patients mainly on long-term treatment with TNFi, higher BMI was significantly associated with lower adalimumab and etanercept serum trough levels and higher disease activity.

Pharmacokinetics and safety of CT-P17 (40 mg/0.4 ml) versus reference adalimumab: randomized study in healthy Japanese adults.

Aim: Comparing pharmacokinetics and safety of CT-P17 and EU-approved reference adalimumab (EU-adalimumab) in Japan. Materials & methods: Double-blind, parallel-group phase I trial at three hospitals. Healthy Japanese adults were randomized (1:1) to CT-P17 or EU-adalimumab (single 40-mg subcutaneous dose). The primary end point was pharmacokinetic equivalence for area under the concentration-time curve from time zero to infinity and maximum serum concentration. Results: Of the 205 randomized subjects (102 CT-P17, 103 EU-adalimumab), 204 received study drug. CT-P17 and EU-adalimumab were pharmacokinetically equivalent: 90% CIs for geometric least-squares mean ratios were within predefined 80-125% equivalence margins. Secondary pharmacokinetic end points, safety and immunogenicity were similar between the groups. Conclusion: CT-P17 had pharmacokinetics, safety and immunogenicity comparable to EU-adalimumab in healthy Japanese adults.

CT-P17 is a biosimilar that has been determined by the EMA to be highly similar to adalimumab. CT-P17 is approved to treat the same inflammatory conditions as reference adalimumab. CT-P17 is formulated at a high concentration (40 mg/0.4 ml) and may be associated with less injection-site pain than the original lower-concentration formulation of the reference product. In this study, healthy Japanese adults were given a single dose of either CT-P17 or EU-approved reference adalimumab. Pharmacokinetics (drug absorption, distribution, metabolism and excretion), safety and immunogenicity (occurrence of immune response to the drug) were comparable between the two groups. Previous studies with CT-P17 did not take place in Japan. These results support applying the conclusions regarding CT-P17 biosimilarity from other studies to the Japanese population.

An Update Review of Biosimilars of Adalimumab in Psoriasis - Bioequivalence and Interchangeability.

Biologic drugs have revolutionized the treatment of psoriasis and other rheumatological diseases. In recent years, many biosimilar agents that are highly similar in structure and function to their originator products have been developed, including the tumor necrosis factor-alpha antagonist adalimumab. The considerably lower cost of these products has greatly cut the economic burden of the patients and increased the accessibility of biologic therapies worldwide. The US Food and Drug Administration and/or the European Medicines Agency have approved eight biosimilars of adalimumab (ABP 501/BI 695501/SB5/GP2017/FKB327/MSB11022/PF-06410293/CT-P17) for the treatment of psoriasis, and others are under review. Given that these agents showed pharmacokinetic, efficacy, safety, and immunogenicity profiles comparable to those of the originator, adalimumab biosimilars were licensed for all indications approved for reference adalimumab based on extrapolation; however, some of the equivalence studies were only conducted in one or two disease populations. This review discusses the bioequivalence of adalimumab biosimilars as demonstrated by various clinical trials, the extrapolation of indications, guidance and policies of the EU and US on interchangeability (nonmedical switching/automatic substitution) between biosimilars and originators, and the real-life practices of switching from reference adalimumab to the respective biosimilars. Further data from real-world studies and post-marketing analyses are needed better to address the efficacy and safety of the transition strategy.

Therapeutic monitoring of adalimumab at non-trough levels in patients with inflammatory bowel disease.

Adalimumab (ADA) trough level and anti-ADA antibody (AAA) positivity influence mucosal healing and loss of response in patients with inflammatory bowel disease (IBD). In this study, we clarified the correlation between ADA monitoring, including non-trough level, and real-world IBD clinical outcomes. This retrospective, observational, single-center study involved patients with ulcerative colitis (19) and Crohn's disease (33) treated with ADA from January 2007 to August 2018. Serum ADA and AAA levels were measured 4‒14 days after ADA administration. The AAA positivity rate was 23.1% (12/52). ADA continuity was higher in AAA-negative patients than in AAA-positive patients (P = 0.223). Receiver operating characteristic (ROC) analysis revealed that a serum AAA cut-off of 9.2 µg/mL was associated with ADA continuity. The ADA level was significantly higher in the endoscopic remission group than in the non-remission group (P = 0.02). Based on the ROC curve analysis results of serum ADA level and endoscopic remission, the cut-off value of the serum ADA level was set to 11.1 µg/mL. Under the combined use of ADA with immunomodulators and AAA positivity, ADA continuity was significantly higher when the serum AAA level at 4-14 days after ADA administration was ≥9.2 µg/mL. Furthermore, endoscopic remission can be expected with a serum ADA level of ≥11.1 µg/mL. Overall, to predict clinical outcomes, it would be useful to measure the blood level of ADA regardless of the timing of the trough.

Pharmacokinetics, safety, and immunogenicity of HLX03, an adalimumab biosimilar, compared with reference biologic in healthy Chinese male volunteers: Results of a randomized, double-blind, parallel-controlled, phase 1 study.

The primary objective of this randomized, double-blind, parallel-controlled study (from December 2016 to October 2018) was to evaluate pharmacokinetic (PK) equivalence of adalimumab biosimilar HLX03 and reference adalimumab in healthy volunteers, and to assess safety, and immunogenicity of HLX03. The primary PK endpoints were maximum observed plasma concentration (Cmax ) and area under the concentration curve from time zero to the last quantifiable concentration (AUC0-t ). Equivalence was determined if the 90% confidence interval (CI) of geometric least square mean ratio between the two treatment groups were within the predefined range of 80%-125%. Safety and immunogenicity were monitored during the study. Healthy Chinese males (N = 220) were randomized 1:1 to receive a single subcutaneous 40 mg dose of HLX03 or China (CN)-sourced adalimumab. The ratios of the geometric mean of Cmax and AUC0-t were 102.2% and 105.7%, respectively, with corresponding 90% CIs falling in the predefined margins, which demonstrated PK equivalence between HLX03 and CN-adalimumab. The incidence of treatment-emergent adverse events (TEAEs) was similar in the two groups (73.8% and 66.0% in the HLX03 and CN-adalimumab groups, respectively). Grade 3-4 TEAEs were reported in 7.5% and 5.7% of participants, respectively. The incidences of participants with antidrug antibodies (HLX03: 96.2%; CN-adalimumab: 93.4%) or neutralizing antibodies (HLX03: 40.6%, CN-adalimumab: 41.4%) were comparable between groups. This study demonstrated PK bioequivalence between HLX03 and CN-adalimumab, with similar safety and immunogenicity profiles. These data support further clinical development of HLX03 as an adalimumab biosimilar.

Pharmacokinetic equivalence of CT-P17 to high-concentration (100 mg/ml) reference adalimumab: A randomized phase I study in healthy subjects.

This study aimed to demonstrate pharmacokinetic (PK) equivalence of a single dose of the proposed adalimumab biosimilar CT-P17 to United States-licensed adalimumab (US-adalimumab) and European Union-approved adalimumab (EU-adalimumab). This double-blind, parallel-group, phase I trial (clinicaltrials.gov NCT03970824) was conducted at 10 hospitals (Republic of Korea), in which healthy subjects (1:1:1) were randomized to receive a single 40 mg (100 mg/ml) subcutaneous injection of CT-P17, US-adalimumab, or EU-adalimumab. Primary end points were PK equivalence in terms of: area under the concentration-time curve from time zero to infinity (AUC0-inf ); AUC from time zero to the last quantifiable concentration (AUC0-last ); and maximum serum concentration (Cmax ). PK equivalence was concluded if 90% confidence intervals (CIs) for percent ratios of geometric least squares means (GLSMs) for pairwise comparisons were within the equivalence margin of 80-125%. Additional PK end points, safety, and immunogenicity were evaluated. Of the 312 subjects who were randomized (103 CT-P17; 103 US-adalimumab; 106 EU-adalimumab), 308 subjects received study drug. AUC0-inf , AUC0-last , and Cmax were equivalent among CT-P17, US-adalimumab, and EU-adalimumab, because 90% CIs for the ratios of GLSMs were within the 80-125% equivalence margin for each pairwise comparison. Secondary PK end points, safety, and immunogenicity were similar between treatment groups. In conclusion, PK equivalence for single-dose administration of CT-P17, EU-adalimumab, and US-adalimumab was demonstrated in healthy adults. Safety and immunogenicity profiles were comparable between treatment groups and consistent with previous reports for adalimumab biosimilars.

Is There a Role for Therapeutic Drug Monitoring in Patients with Hidradenitis Suppurativa on Tumor Necrosis Factor-α Inhibitors?

Tumor necrosis factor-α inhibitors, adalimumab and infliximab, are at the forefront of biologic therapy for the management of moderate-to-severe hidradenitis suppurativa, with adalimumab as currently the only approved medication for this condition. In treating patients, primary or secondary lack of response (also termed suboptimal response) is a major burden for both patients and healthcare systems and is a challenge with biologics in part owing to the development of anti-drug antibodies following treatment. To overcome this, therapeutic drug monitoring may be conducted proactively or reactively to a patient's suboptimal response guided by measurements of trough serum drug concentrations and levels of anti-drug antibodies. While strong evidence to support the utility of therapeutic drug monitoring exists in patients with inflammatory bowel disease, current information is limited in the context of hidradenitis suppurativa. We sought to summarize the available evidence and to present the role of therapeutic drug monitoring and other dose optimization strategies in improving clinical response in patients with hidradenitis suppurativa treated with tumor necrosis factor-α inhibitors.

A Randomized, Double-Blind, Parallel-Group, Phase 1 Clinical Trial Comparing the Pharmacokinetic, Safety, and Immunogenicity of the Biosimilar HS016 and the Originator Adalimumab in Chinese Healthy Male Subjects.

A comparison of the immunogenicity, safety, and pharmacokinetic properties of HS016 and its originator, adalimumab, was conducted in Chinese healthy male subjects. This was a phase 1 single-center, randomized, parallel-group double-blind clinical trial. Chinese healthy male subjects (1:1) allocated to HS016 and adalimumab groups were treated with single subcutaneous injections (40 mg/0.8 mL). The pharmacokinetic equivalence of HS016 and adalimumab was assessed by (1) the area under the plasma concentration-time curve (AUC) from time 0 to the last detectable drug concentration (AUC0-t ), (2) the AUC from time 0 extrapolated to infinity (AUC0-∞ ), and (3) the maximum plasma concentration (Cmax ). Other pharmacokinetic parameters (time to Cmax , apparent clearance, and half-life), safety, and immunogenicity were also evaluated. A total of 136 subjects were randomly divided into HS016 (n = 68) or adalimumab (n = 68) groups. The geometric means of AUC0-t , AUC0-∞ , and Cmax were similar for HS016 and adalimumab. The 90%CIs of AUC0-t (87.2% to 106.1%), AUC0-∞ (87.4% to 108.4%), and Cmax (98.6% to 113.6%) were all within the prespecified bioequivalence criteria (80% to 125%). The incidence of treatment-emergent adverse events (TEAEs) was similar in both groups, with most TEAEs being mild; only 3 (4.4%) subjects in the HS016 group experienced moderate TEAEs. No significant differences in the time to Cmax , apparent clearance, half-life, and immunogenicity were detected. The pharmacokinetic profile of HS016 was equivalent to that of the originator, adalimumab, with similar safety and immunogenicity profiles. HS016 may be considered for assessment in the treatment of patients with ankylosing spondylitis.

Therapeutic Drug Monitoring in Patients with Suboptimal Response to Adalimumab for Hidradenitis Suppurativa: A Retrospective Case Series.

BACKGROUND: Adalimumab, a tumor necrosis factor-α inhibitor, is a biologic used for the treatment of moderate-to-severe hidradenitis suppurativa (HS). It is well known that patients may experience loss of efficacy from its use in other conditions, and it is suggested that developing a strategy for therapeutic drug monitoring (TDM) may help secure optimal clinical outcomes. OBJECTIVES: We sought to determine serum adalimumab concentrations and anti-adalimumab antibody (AAA) status in patients with moderate-to-severe HS. METHODS: A retrospective case series of 38 patients with suboptimal response to adalimumab 40 mg weekly was conducted at a community dermatology clinic. Adalimumab serum trough levels, AAA status, and inflammatory biomarkers were collected. Blood was drawn on identification of suboptimal response (after a minimum of 12 weeks) and was collected once prior to receiving the next scheduled dose. Kruskal-Wallis and Chi-squared tests were used for data analysis. RESULTS: A total of 38 patients had a median adalimumab trough concentration of 8.76 (interquartile range [IQR] 1.3-12.5) µg/mL. The median duration of adalimumab therapy of all patients was 21 (IQR 12-24) months. AAAs were detected in nine patients (24%), and all had subtherapeutic serum concentrations (< 6 µg/mL). Patients who were AAA+ had a significantly lower median adalimumab concentration than those who were AAA- (0.02 µg/mL [range 0.02-0.81] vs. 10.14 [range 0.76-48.00]; p = 0.0006). CONCLUSION: Patients with AAAs had significantly lower serum adalimumab levels. The current study suggests that TDM may identify underlying reasons for suboptimal response and detect patients who may benefit from dose optimization strategies.

Higher Maintenance Adalimumab Trough Levels are Associated With Achievement of Advanced Remission Targets in Patients With Inflammatory Bowel Disease.

BACKGROUND: Biomarker normalization and endoscopic remission are superior to clinical remission in achieving improved long-term clinical outcomes in patients with inflammatory bowel diseases. GOAL: To study whether higher maintenance adalimumab levels are associated with clinical remission, biomarker normalization, and endoscopic remission. STUDY: Data were collected retrospectively from the patients' medical records. We defined clinical remission as a Harvey Bradshaw Index ≤5 or a partial Mayo score ≤2 for Crohn's disease (CD) and ulcerative colitis (UC), respectively, biomarker normalization as a C-reactive protein <0.5 mg/dL and/or calprotectin <250 (mg/kg), endoscopic remission as a (simple endoscopic score-CD) ≤3/4 for ileal/extensive CD, respectively, or an endoscopic Mayo score ≤1 for UC, and deep remission as the combination of clinical and endoscopic remission with normal biomarkers. RESULTS: Ninety-seven patients were included (82 CD and 15 UC). Patients who achieved clinical remission, biomarker normalization, or endoscopic remission had higher serum trough adalimumab levels compared with patients not in remission [mean (M)±standard error (SE)=8.98±0.78 vs. 5.92±0.96 µg/mL; P=0.016, 9.38±0.85 vs. 5.48±0.87 µg/mL; P=0.002; 9.13±0.88 vs. 6.02±0.77 µg/mL; P=0.019, respectively]. Receiver-operating curve analysis showed that an adalimumab level of ≥8.25 µg/mL was associated with deep remission (sensitivity 84%, specificity 70%, area under the curve 0.775; P<0.001). CONCLUSION: Clinical remission, biomarker normalization, and endoscopic remission are positively associated with adalimumab trough levels. Adalimumab level of ≥8.25 µg/mL is associated with deep remission. This study provides additional data to guide therapeutic drug monitoring with adalimumab.

The Effect of Adiposity on Anti-Tumor Necrosis Factor-Alpha Levels and Loss of Response in Crohn's Disease Patients.

INTRODUCTION: A high body mass index is known to adversely affect antitumor necrosis factor-alpha trough levels and secondary loss of response (SLOR) in patients with Crohn's disease. We hypothesize that high levels of adiposity negatively affect these outcomes and aimed to determine if this relationship exists. METHODS: We performed a retrospective cross-sectional study of 69 patients with Crohn's disease from two tertiary inflammatory bowel disease centers between February 1, 2015, and June 30, 2018. Primary responders to infliximab (IFX) or adalimumab (ADA) who had a trough level performed within 6 months of CT or MRI scan and at least 12 months of clinical follow-up were eligible for inclusion. Body composition as measured on CT/MRI scans were correlated with trough concentration and time SLOR. Multivariate adjustments were made for established risk factors known to affect trough levels and SLOR. RESULTS: Of 69 included patients, 44 (63.8%) and 25 (36.2%) patients received IFX and ADA, respectively. Multivariate analysis revealed that IFX trough concentrations were inversely correlated with visceral fat area (-0.02 [-0.04, -0.003], P = 0.03), visceral fat index (-0.07 [-0.12, -0.01], P = 0.02) and visceral fat: skeletal muscle area ratio (-3.81 [-7.13, -0.50], P = 0.03), but not body mass index (-0.23 [-0.52, 0.06], P = 0.11). No predictive factors were found for ADA. Increased total adipose area was associated with an increased risk of SLOR in ADA-treated patients, but not IFX-treated patients (hazard ratio = 1.01 [1.002, 1.016], P = 0.011). DISCUSSION: Visceral adiposity is an important predictor of IFX trough levels, and high total adiposity predicts for SLOR to ADA.

Biomarkers of disease activity and other factors as predictors of adalimumab pharmacokinetics in inflammatory bowel disease.

Inflammatory bowel disease (IBD) is commonly treated with adalimumab. The main objective of the study was to develop a population pharmacokinetic model of adalimumab in IBD patients evaluating the potential biomarkers of disease activity and other factors and its implications in adalimumab dosing. A prospective observational study was performed in adult patients diagnosed with Crohn's disease and ulcerative colitis treated with adalimumab and following a proactive therapeutic drug monitoring of serum concentrations. Adalimumab serum concentrations (ASC) were quantified mainly prior the administration using an enzyme-linked immunosorbent assay (ELISA). A population pharmacokinetic model was developed based on 303 ASC data of 104 IBD patients using non-linear mixed effect modelling approach. Sixty-five ASC from 20 additional patients were randomly selected as an external validation group. A one-compartment model with first order absorption and elimination best describe the ASC time course. Body mass index (BMI), faecal calprotectin (FCP), unexplained decline in ASC and the specific administration pen device exhibited significant influence on apparent clearance (p-value < 0.001). FCP was the inflammatory activity biomarker showing the most relevant impact on adalimumab exposure, higher than C-reactive protein and albumin, and may be useful for adalimumab dosing adjustment. The population-based pharmacokinetic model developed adequately characterized adalimumab exposure in IBD patients. The unexplained decline in ASC, FCP, BMI and the specific administration pen device were identified as meaningful variables significantly influencing adalimumab pharmacokinetics.

Usefulness of monitoring antitumor necrosis factor serum levels during the induction phase in patients with Crohn's disease.

AIMS: The aims of this study were (a) to know the kinetics of antitumor necrosis factor (TNF) drug serum levels during the induction phase in patients with Crohn's disease; (b) to identify variables associated with these levels; and (c) to assess the relation between these levels and short-term effectiveness in Crohn's disease patients. METHODS: Patients with Crohn's disease naïve to anti-TNF treatment were prospectively included. Remission was defined as a Crohn's disease activity index (CDAI) score <150 after 14 weeks of treatment. Blood samples were obtained at baseline and at weeks 4, 8, and 14. Adalimumab and infliximab levels were measured, receiver operating characteristic (ROC) curves were constructed, and the area under the ROC curve was calculated. RESULTS: One-hundred fifty patients with Crohn's disease were included, 79 (53%) received infliximab and 71 (47%) had CDAI > 150 at study entry. At week 14, 52 out of 71 patients with CDAI > 150 at baseline (73%) had clinical remission. There were no differences in infliximab levels between patients with and without remission (8 vs. 9.1 µg/mL, P > 0.05) or with and without response (7 vs. 11 µg/mL, P > 0.05) at week 14. There was a trend to higher levels of adalimumab concentration in responders in comparison with nonresponders (13 vs. 6.7 µg/mL, P = 0.05) and in patients who achieved remission in comparison with nonremitters (13.5 vs. 8.4 µg/mL, P = 0.06). In the multivariate analysis, no variable was predictive of short-term remission, including infliximab and adalimumab serum levels. CONCLUSION: Determining anti-TNF serum levels during the induction phase is not useful for predicting short-term remission in patients with Crohn's disease.

Lower adalimumab trough levels are associated with higher bowel wall thickness in Crohn's disease.

BACKGROUND: In Crohn's disease, higher adalimumab trough levels and negative anti-adalimumab-antibodies associate with better clinical and endoscopic outcomes. Intestinal ultrasound has become a relevant non-invasive method to monitor treatment. However, data on the association between adalimumab levels and bowel wall thickness measured with ultrasound is limited. OBJECTIVE: The purpose of this study was to examine the possible association between the sonographic transmural-thickness and adalimumab trough levels. METHODS: This prospective observational cohort study was conducted at Sheba Medical Center in 2014-2018. Crohn's disease patients on adalimumab maintenance therapy with intestinal ultrasound performed within <30 days of trough level measurement were included. Associations between terminal ileum and colonic thickness, adalimumab levels and therapy retention were assessed. RESULTS: Fifty events of ultrasound with concomitant adalimumab trough level measurements in 44 Crohn's disease patients were included. Patients with trough level <3 µg/ml had significantly higher bowel wall thickness, both for terminal ileum (p = 0.04) and colon (p = 0.02). Thirty-two patients continued adalimumab therapy over one year. The adalimumab retention rate was higher among those with terminal ileum thickness <4 mm (p = 0.03). CONCLUSION: Lower adalimumab trough levels were associated with higher bowel wall thickness indicating poorer therapy outcome. Transmural thickness measurement with ultrasound may be a useful target for guiding biologic therapy in Crohn's disease.

Comparison of the Efficacy and Safety of Adalimumab (Humira) and the Adalimumab Biosimilar Candidate (HS016) in Chinese Patients with Active Ankylosing Spondylitis: A Multicenter, Randomized, Double-Blind, Parallel, Phase III Clinical Trial.

OBJECTIVE: The aim of this study was to evaluate the efficacy and safety of the biosimilar candidate of adalimumab (HS016) compared with adalimumab (Humira) for the treatment of active ankylosing spondylitis. METHODS: A multicenter, randomized, double-blind, parallel, positive control, phase III clinical trial was conducted at 28 locations in China. Patients with active ankylosing spondylitis were randomized in a 2:1 ratio to subcutaneously receive 40 mg of either HS016 or adalimumab every other week for 24 weeks. The primary endpoint was to achieve at least a 20% improvement (ASAS20) in patients at 24 weeks according to the Assessment of Spondyloarthritis International Society criteria. The secondary endpoint included other efficacy assessment parameters, health evaluations, safety, pharmacokinetic, and immunogenicity parameters. RESULTS: Following the random assignment of 648 patients into HS016 (n = 416) and adalimumab (n = 232) groups, no significant difference was found in the ASAS20 response rates at 24 weeks between the HS016 (364/416, 87.5%) and adalimumab (209/232, 90.1%) treatments and the difference between the response rates (- 2.59%; 90% confidence interval [CI] - 6.77 to 1.60) was within the predefined equivalence margin (± 15%). There were also no significant differences when the secondary endpoints were compared (all p > 0.05). Similarly, the rates of treatment-emergent adverse events (TEAEs) were not significantly different between the two groups, with most TEAEs being mild to moderate. Only nine severe cases were found, including seven within the HS016 group, three (0.7%) of which were tuberculosis cases. Plasma concentrations of HS016 and adalimumab from weeks 12 to 14 were similar during the steady-state period and steady-state maximal concentration (Cmax,ss) was equivalent for HS016 (7356.6 ng/mL) and adalimumab (7600.3 ng/mL). The accumulated proportion of patients with positive human anti-human antibodies (HAHAs) at week 24 was 326/412 (79.1%) in the HS016 group and 183/229 (79.9%) in the adalimumab group (p > 0.05), while the accumulated proportion of patients with positive neutralizing antibody (NAb) tests were 72/412 (17.5%) in the HS016 group and 43/229 (18.8%) in the adalimumab group (p > 0.05). CONCLUSION: HS016 resembled adalimumab in efficacy and safety over the 24-week treatment period. TRIAL REGISTRATION NUMBER: ChiCTR1900022520.

Comparative nonclinical assessments of the biosimilar PF-06410293 and originator adalimumab.

Adalimumab, a recombinant fully human monoclonal antibody targeting tumor necrosis factor (TNF), is approved in the United States and Europe to treat various inflammatory and autoimmune indications. Biosimilars are approved biologics highly similar, but not identical, to approved biotherapeutics. To support clinical development of PF-06410293, an adalimumab biosimilar, nonclinical studies evaluated the structural, functional, toxicologic, and toxicokinetic similarity to originator adalimumab sourced from the United States (adalimumab-US) and European Union (adalimumab-EU). Structural similarity was assessed by peptide mapping. Biologic activity was measured via inhibition of TNF-induced apoptosis and Fc-based functionality assessments. In vivo nonclinical similarity was evaluated in a toxicity study in cynomolgus monkeys administered subcutaneous PF-06410293 or adalimumab-EU (0 or 157 mg/kg/week). Peptide mapping demonstrated PF-06410293, adalimumab-US, and adalimumab-EU had identical amino acid sequences. Comparative functional and binding assessments were similar. Effects of PF-06410293 and adalimumab-EU were similar and limited to pharmacologically mediated decreased cellularity of lymphoid follicles and germinal centers in spleen. Toxicokinetics were similar; maximum plasma concentration and area-under-the-concentration-time curve ratio of PF-06410293:adalimumab-EU ranged from 1.0 to 1.2. These studies supported PF-06410293 entry into clinical development. Many regulatory agencies now only request nonclinical in vivo testing if there is residual uncertainty regarding biosimilarity after in vitro analytical studies.

Proactive Monitoring of Adalimumab Trough Concentration Associated With Increased Clinical Remission in Children With Crohn's Disease Compared With Reactive Monitoring.

BACKGROUND & AIMS: Proactive monitoring of drug trough concentrations and antibodies against drugs might help determine whether patients are likely to respond to treatment and increase efficacy. We investigated whether proactive drug monitoring is associated with higher rates of clinical remission in pediatric patients with Crohn's disease (CD). METHODS: We performed a nonblinded, randomized controlled trial of 78 children with CD (6-18 years old; 29% female; mean age, 14.3 ± 2.6 years) who had not received prior treatment with a biologic agent but had responded to adalimumab induction therapy, under scheduled monitoring of clinical and biologic measures (based on clinical factors and levels of C-reactive protein and fecal calprotectin), at pediatric gastroenterology units in Israel from July 2015 through December 2018. The patients were randomly assigned to groups that received proactive monitoring (trough concentrations measured at weeks 4 and 8 and then every 8 weeks until week 72, n = 38) or reactive monitoring (physicians were informed of trough concentrations after loss of response, n = 40). In both groups, doses and intervals of adalimumab were adjusted to achieve trough concentrations of 5 µg/mL. The primary endpoint was sustained corticosteroid-free clinical remission at all visits (week 8 through week 72). RESULTS: The primary endpoint was achieved by 31 children (82%) in the proactive group and 19 children (48%) in the reactive group (P = .002). Sixteen patients in the proactive monitoring group (42%) achieved a composite outcome of sustained corticosteroid-free remission, C-reactive protein ≤0.5 mg/dL, and level of fecal calprotectin ≤150 µg/g compared with 5 patients in the reactive monitoring group (12%) (P = .003). By week 72 of treatment, 33 patients in the proactive monitoring group had received adalimumab intensification (87%) compared with 24 patients in the reactive monitoring group (60%) (P = .001). CONCLUSIONS: In a randomized controlled trial of pediatric patients with CD, we found that proactive monitoring of adalimumab trough concentrations and adjustment of doses and intervals resulted in significantly higher rates corticosteroid-free clinical remission than reactive monitoring (measuring trough concentration after loss of response). Clinicaltrials.gov no.: NCT02256462.

Therapeutic drug monitoring to improve outcome of anti-TNF drugs in pediatric inflammatory bowel disease.

Introduction: Medical treatment of pediatric inflammatory bowel diseases (IBD) has been greatly changed by the introduction of a number of biologic agents that are able to target various players of the immune response. In particular, monoclonal antibodies against the pro-inflammatory cytokine TNF-alpha (TNF) such as infliximab, adalimumab, and golimumab are now in the clinics both in induction and maintenance therapy, and several efforts are currently ongoing to optimize the use of these drugs in children. Areas covered: This review focuses on therapeutic drug monitoring (TDM) of anti-TNF levels and antidrug antibodies (ADAs), in IBD children. A revision of the analytical assays used for assessing anti-TNF plasma levels is also provided. Expert opinion: Although there is a consensus across studies that higher anti-TNF trough levels are associated with a better clinical outcome, and that early anti-TNF serum measurements could be predictive of long-term response, it is still not clear what the best predictive time of sampling is and what the ideal target drug plasma concentration to achieve. Indeed, there are a number of published studies, particularly in pediatric cohorts, limited by the population size analyzed and more prospective large studies are needed to examine the value of these predictive markers.

A Narrative Review on Anti-Tumor Necrosis Factor α Therapies in Inflammatory Bowel Disease During Pregnancy: Immunoglobulin Placental Translocation and its Impact.

INTRODUCTION: Inflammatory bowel disease activity is associated with adverse pregnancy outcomes. Anti-tumor necrosis factor α therapy is often required to treat flares and to maintain disease remission. However, there are concerns regarding treatment with these agents during pregnancy, as they actively cross the placental barrier. MATERIAL AND METHODS: Studies regarding anti-tumor necrosis factor α therapy during pregnancy were identified from PubMed from 1958 to January 2018. The reference lists of the selected studies were reviewed to identify complementary publications. RESULTS AND DISCUSSION: Anti-tumor necrosis factor α agents are efficient treatments for moderate-to-severe inflammatory bowel disease and may ensure remission during pregnancy. Although these drugs cross the placenta, they are considered safe for both the mother and the fetus. Furthermore, up-to-date guidelines support therapy continuation during pregnancy aiming for disease control. The same guidelines also consider stopping treatment during the third trimester to limit maternal-fetal drug transfer. However, data shows that this strategy does not completely prevent fetus exposure. In addition, stopping treatment incurs in risk of disease flare and threatens subsequent therapy response. Fetus drug exposure has not showed an association with adverse childhood development. However, as infant drug levels could be detected up to seven months after birth, postponement of live virus vaccination is recommended. CONCLUSION: There should be no disagreement among the medical community as to the need to maintain therapy aiming for disease remission during gestation in inflammatory bowel disease. Anti-tumor necrosis factor α agents are safe for both the mother and the fetus.

Introdução: O melhor preditor de complicações durante a gravidez, na doença inflamatória intestinal, é a atividade da doença. A terapêutica com agentes anti-tumor necrosis factor α atravessa a barreira placentária o que levanta questões relativamente à sua segurança durante a gravidez. Material e Métodos: Revisão bibliográfica suportada a partir de artigos indexados na PubMed (1958 a 01/2018) sobre a terapêutica anti-tumor necrosis factor α durante a gravidez na doença inflamatória intestinal. Resultados e Discussão: Os agentes anti-tumor necrosis factor α são eficazes na doença inflamatória intestinal e podem garantir a remissão clínica durante a gravidez. Estes fármacos atravessam a barreira placentária, mas são seguros para a mãe e feto. Neste sentido, as orientações atuais defendem a manutenção terapêutica durante a gravidez para assegurar a remissão clínica. Paralelamente, as mesmas orientações consideram a suspensão terapêutica durante o terceiro trimestre para limitar a exposição fetal ao fármaco. No entanto, esta estratégia não só não previne totalmente a exposição fetal, como aumenta o risco de agudização da doença e da perda de resposta à terapêutica após o seu reinício. Esta exposição fetal não está associada a alterações do desenvolvimento in utero ou neonatal. Ainda assim, uma vez que é possível dosear fármaco no recém-nascido até aos sete meses de vida, recomenda-se adiar a administração de vacinas vivas em recém-nascidos expostos. Conclusão: Não deve haver discordância na comunidade médica quanto à necessidade de garantir a remissão da doença inflamatória intestinal durante a gestação. Os agentes anti-tumor necrosis factor α devem ser vistos como opções terapêuticas seguras para mãe e feto durante a gravidez.

Subcutaneous Absorption Contributes to Observed Interindividual Variability in Adalimumab Serum Concentrations in Crohn's Disease: A Prospective Multicentre Study.

BACKGROUND AND AIM: Therapeutic drug monitoring is used to optimise adalimumab therapy in patients with Crohn's disease [CD]. However, the interindividual variability in drug absorption and the quantitative effect on drug clearance of anti-adalimumab antibodies [AAA], measured with a drug-resistant assay, are unclear. We aimed to characterise adalimumab population pharmacokinetics [PopPK] and identify determinants of interindividual variability in patients with CD. METHODS: In a prospective multicentre open-label cohort study in 28 patients with CD starting adalimumab therapy peak, intermediate, and trough serum samples were analysed for adalimumab and AAA concentrations using a drug resistant assay. Adalimumab concentration-time data were analysed by non-linear mixed effects modelling and were adequately described by a PopPK model with first-order absorption and one-compartment disposition with linear elimination. Clinical remission at Week 12 [W12] was defined as a Harvey-Bradshaw index ≤4. RESULTS: The absorption rate, volume of distribution, and clearance estimates of a typical patient were respectively 0.343 /day, 7.8 L, and 0.330 L/day. A 4-fold difference in the range of adalimumab concentrations was observed 7 days after the first dose and found to be inversely correlated with baseline lean body weight [LBW], soluble tumour necrosis factor [s-TNF], and s-TNF receptor-1 whereas positive AAA and higher LBW were found to be important predictors of accelerated clearance. An adalimumab concentration at W12 of >7.3 µg/mL was significantly associated with achieving clinical remission at W12. CONCLUSION: Variability in subcutaneous drug absorption is an important contributor to the observed interindividual variability in adalimumab concentrations, in addition to drug clearance [ClinicalTrials.gov NCT02450513].