Yarur, Andrés

Therapeutic drug monitoring (TDM) of biologics is a rapidly evolving field. We aimed to provide a consensus statement regarding the clinical utility of TDM for biologics in inflammatory bowel disease (IBD). A modified Delphi method was applied to develop consensus statements. A comprehensive literature review was performed regarding TDM of biologic therapies in IBD, and 45 statements were subsequently formulated on the potential application of TDM in IBD. The statements, along with literature, were then presented to a panel of 10 gastroenterologists with expertise in IBD and TDM who anonymously rated them on a scale of 1–10 (1 = strongly disagree and 10 = strongly agree). An expert consensus development meeting was held virtually to review, discuss, refine, and reformulate statements that did not meet criteria for agreement or that were ambiguous. During the meeting, additional statements were proposed. Panelists then confidentially revoted, and statements rated ≥7 by 80% or more of the participants were accepted. During the virtual meeting, 8 statements were reworded, 7 new statements were proposed, and 19 statements were rerated. Consensus was finally reached in 48/49 statements. The panel agreed that reactive TDM should be used for all biologics for both primary nonresponse and secondary loss of response. It was recommended that treatment discontinuation should not be considered for infliximab or adalimumab until a drug concentration of at least 10–15 μg/mL was achieved. Consensus was also achieved regarding the utility of proactive TDM for anti–tumor necrosis factor therapy. It was recommended to perform proactive TDM after induction and at least once during maintenance. Consensus was achieved in most cases regarding the utility of TDM of biologics in IBD, specifically for reactive and proactive TDM of anti–tumor necrosis factors.

Abstract Background Pivotal trials have shown that ustekinumab (UST) is effective in ulcerative colitis (UC). However, the population included in these trials do not always represent the cohort of patients treated in the “real world”. In this study, we aimed to describe the effectiveness and safety of UST in a clinical cohort of patients with UC Methods We performed a multi-center cohort study and included patients with active UC starting UST. Variables collected included demographics, previous and current UC medications, disease activity (measured using partial and endoscopic Mayo score [PMS and EMS]) at 8 weeks, 6 months and end of follow-up. We also abstracted UST drug level and anti-UST antibodies (AUA), albumin and C-reactive protein levels. Primary outcomes were clinical response at week 8 defined as a reduction of 3 points in the PMS or PMS<2. Secondary outcomes were clinical remission defined as a PMS <2 and endoscopic remission defined as a MES ≤1, and the development of an adverse event (AE) attributed to UST. Results Ninety-five patients were included with a median age of 42 years (IQR:32-57) and 53 (56%) were female. Median follow-up was 5 months (IQR:2.2-7.4). Only 4 (4.3%) were naïve to biologics or tofacitinib and 62 (66%) had previous exposure to at least 2 other biologics. No variables were found to be associated with response at week 8 (Figure 2). Those patients who responded at week 8 had higher median albumin levels vs those who did not (median of 4.4 [IQR: 4.1-4.6] vs 4.1 g/dL [IQR:3.8-4.3]; p=0.02). There were no differences in baseline CRP levels (1mg/dL [IQR:0.6-2.8] vs 0.6 mg/dL [0.3-1.5]; p=0.06). Among the 33 patients who had follow-up endoscopic assessment, 7 (21.2%) had achieved endoscopic remission and 4 (12%) achieved histologic remission. Median UST level was 4.1 mcg/ml (IQR:2.5-5.1) and no patients had detectable AUA. Five patients underwent colectomy (5.3%). Only 6 patients (6.6%) presented with an AE (all minor that included, rash, headaches, arthralgias and infection). Conclusion In a population enriched with refractory UC, UST was well tolerated and induce response and remission in a significant number of patients. The rate of response was lower in obese patients and those with extensive colitis but was not associated with previous exposure to biologics and/or tofacitinib. Larger studies with a longer follow-up are warranted. Figure 1: Rates of clinical response and remission in patients with UC receiving ustekinumab Figure 2: Association between several baseline characteristics and response to ustekinumab in UC

Abstract Background IV ciclosporin therapy is effective in steroid-refractory ulcerative colitis. The optimal drug level to achieve response and minimize complications during induction therapy is not known. Aim The primary aim was to evaluate if serum ciclosporin drug levels are associated with increased risk of colectomy within 90 days of hospitalization. Secondary aims were to determine if ciclosporin levels are associated with avoidance of colectomy at 7 and 30 days, if ciclosporin levels are associated with drug-related and postoperative complications, and if patient-specific factors are associated with response to ciclosporin. Methods We conducted a retrospective analysis of 81 hospitalized patients with steroid-refractory ulcerative colitis treated with ciclosporin. Risk factors for colectomy within 7, 30, and 90 days, medication-specific and postoperative complications were compared by first, mean, and peak ciclosporin level during IV induction therapy. Results There were 47 patients (58%) who underwent surgery. There were no differences between initial, mean, and peak ciclosporin levels among responders and nonresponders and treatment-related or postoperative complications. Responders within 90 days had lower C-reactive-protein levels (20mg/L vs. 38mg/L, P = 0.01), lower serum albumin concentrations (3.4g/dL vs. 3.7g/dL, P = 0.03), and higher rates of kidney injury (50% vs 17%, P = 0.002). Conclusion Initial, mean, and peak serum levels of ciclosporin did not correlate with response or toxicity. However, C-reactive-protein levels levels and kidney injury may be helpful in predicting clinical response to ciclosporin.