Dervieux, Thierry

Background/Objectives: This study aimed to establish the clinical utility of a therapeutic drug monitoring (TDM)-supported, model-informed precision dosing (MIPD) approach (precision-guided dosing [PGD]) by assessing the impact of pharmacokinetic (clearance [CL]) and clinical laboratory parameters on adalimumab (ADA) dosage adjustments during maintenance therapy for inflammatory bowel disease (IBD). Methods: In the EMPOWER study, blood was collected at any time post-ADA injection. Pharmacokinetic (PK) testing was conducted in an accredited lab. Inputs for the PGD test included ADA concentrations, antibodies to ADA, albumin levels, and the current dosing regimen. CL was calculated using nonlinear mixed-effect models. Results were reported to health care providers (HCPs) within 3 days. HCPs’ treatment decisions were recorded and classified as treatment reduction, continuation, intensification, or ADA discontinuation. The physician global assessment (PGA) of disease activity was collected. Relationships between drug concentrations, CL, disease activity, and physician decision-making were assessed using logistic regression. Results: A total of 213 cases were assessed by 21 HCPs. ADA treatment was intensified in 24% and discontinued in 13% of cases. An ADA concentration ≤ 10 μg/mL was associated with a 23.7-fold and 3.0-fold higher likelihood of therapy intensification and PGA > 0, respectively, compared to concentrations > 10 μg/mL. An ADA concentration < 5 μg/mL was associated with a 3.3-fold higher likelihood of treatment discontinuation. CL ≥ 0.318 L/day was associated with a 10.4-fold higher likelihood of therapy intensification. Higher CL (>0.8 L/day) was associated with a 3.5-fold and 4.2-fold higher likelihood of treatment discontinuation and PGA > 0, respectively. Conclusions: PGD enables earlier and precise optimization of ADA dosing by predicting trough levels at any time during the therapy cycle. Optimized dosing to achieve target ADA concentrations and low clearance is crucial to mitigate therapy discontinuation and active disease in IBD patients.

Abstract Background Biomarkers for predicting the development of Ulcerative Colitis (UC) and disease-related complications are lacking. Anti-integrin αvβ6 IgG autoantibodies (anti-αvβ6) have been recently described in patients diagnosed with UC. Here, we sought to determine if anti-αvβ6 autoantibodies predate UC development and to study associations between anti-αvβ6 and disease outcomes in newly diagnosed UC patients. Methods In a unique pre-clinical IBD cohort from the PRoteomic Evaluation and Discovery in an IBD Cohort of Tri-service Subjects (PREDICTS), anti-αvβ6 were measured in longitudinal pre-diagnosis serum samples from 82 subjects who later developed UC as well as in 82 matched subjects that did not develop IBD (HC). Sample A was at the time of UC diagnosis, Sample B was at a median of 2 years before Sample A, Sample C was at a median of 4 years before Sample A and Sample D was at a median of 10 years before Sample A. In a distinct, external validation cohort (the Crohn’s and Colitis Canada Genetics Environment Microbial (GEM) Project), we tested samples from 12 subjects who later developed UC and compared those with 49 matched subjects who remained asymptomatic. Further, anti-αvβ6 were measured in 2 incident IBD cohorts (COMPASS, n=55 and OSCCAR, n=104 UC subjects) and associations between anti-αvβ6 and adverse UC-outcomes were defined using Cox proportional-hazards model. Results Anti-αvβ6 were significantly higher in the PREDICTS cohort among individuals who developed UC compared to HC up to 10 years prior to diagnosis (Figure 1A). The anti-αvβ6 seropositivity was 12.2% 10 years before diagnosis and increased to 52.4% at the time of diagnosis in subjects who developed UC compared with 2.7% in controls across the 4 timepoints. Additionally, the predictive performance of anti-αvβ6 autoantibodies as assessed via area under the receiver operator curves (AUROC) with 10-fold cross validation was at least 0.8 up to 10 years before diagnosis (Figure 1B). Elevated levels of anti-αvβ6 in pre-clinical UC samples were further validated in the GEM cohort (Figure 1C). Finally, high anti-αvβ6 were associated with a composite of adverse UC-outcomes including hospitalization, disease extension, colectomy, systemic steroid use and/or escalation to biologic therapy in both incident cohorts (Figure 1D). Conclusion Anti-integrin αvβ6 autoantibodies precede the clinical diagnosis of UC by up to 10 years and are associated with adverse UC-related outcomes.