Efficacy of dashboard driven dosing of infliximab in inflammatory bowel disease patients; a randomized controlled trial

OBJECTIVES

Loss of response (LOR) to infliximab (IFX) remains a challenge in the management of inflammatory bowel diseases (IBD). Proactive dosing strategies to achieve and maintain predefined IFX trough levels (TL) may prevent LOR. We aimed to investigate the efficacy of dashboard driven IFX dosing compared to standard dosing in a prospective trial in IBD patients.

METHODS

In this multicentre 1:1 'PRECISION' trial, we randomized IBD patients in clinical remission (Harvey Bradshaw Index ≤4 for Crohn's disease (CD) or a partial Mayo score ≤2 for ulcerative colitis (UC)) receiving IFX maintenance treatment. The precision group (PG) received IFX dosing guided by a Bayesian pharmacokinetic model, aiming to achieve and maintain a TL of 3 µg/ml by treatment (de)escalation as indicated by the dashboard. Patients in the control group (CG) continued treatment without dose adaptations. The primary endpoint was the proportion of patients in sustained clinical remission after 1 year.

RESULTS

Eighty patients were enrolled (66 CD, 14 UC), and the median [interquartile range] age was 37 years [27-51]). After one year, 28/32 (88%) of patients in the PG were in sustained clinical remission versus 25/39 (64%) in the CG (p = .017). PG patients had lower median faecal calprotectin levels after 1 year (p = .031), whereas no significant differences in median CRP levels were found.

CONCLUSION

We demonstrated that the use of a Bayesian dashboard for IFX dosing in maintenance treatment for IBD reduced the incidence of LOR compared to standard dosing. Precision dosing also resulted in lower FCP levels.

CLINICALTRIALS.GOV NUMBER

NCT02453776.

Higher anti-TNF serum levels are associated with perianal fistula closure in Crohn's disease patients

Objectives: Anti-TNF agents are effective to treat perianal Crohn's disease (CD). Evidence suggests that Crohn's disease patients with perianal fistulas need higher infliximab (IFX) serum concentrations compared to patients without perianal CD to achieve complete disease control. Our aim was to compare anti-TNF serum concentrations between patients with actively draining and closed perianal fistulas. Methods: A retrospective survey was performed in CD patients with perianal disease treated with IFX or adalimumab (ADL). Fistula closure was defined as absence of active drainage at gentle finger compression and/or fistula healing on magnetic resonance imaging. Results: We identified 66 CD patients with a history of perianal fistulas treated with IFX (n = 47) and ADL (n = 19). Median IFX serum trough concentrations ([interquartile range]) were higher in patients with closed fistulas (n = 32) compared to patients with actively draining fistulas (n = 15): 6.0 µg/ml [5.4-6.9] versus 2.3 µg/ml [1.1-4.0], respectively (p < .001)). A similar difference was seen in patients treated with ADL: median serum concentrations were 7.4 µg/ml [6.5-10.8] in 13 patients with closed fistulas versus 4.8 µg/ml [1.7-6.2] in 6 patients with producing fistulas (p = .003). Serum concentrations of ≥5.0 µg/ml for IFX (area under the curve of 0.92; 95% CI: 0.82-1.00)) and 5.9 µg/ml for ADL (area under the curve of 0.89; 95% CI 0.71-1.00) were associated with fistula closure. Conclusion: Cut-off serum concentrations ≥5.0 µg/ml for IFX and ≥5.9 µg/ml for ADL were associated with perianal fistula closure. Hence, patients with producing perianal fistulas may benefit from anti-TNF dose intensification to achieve fistula closure.

Mucosal morphology in Barrett's esophagus: interobserver agreement and role of narrow band imaging

BACKGROUND AND STUDY AIMS

We have recently proposed a classification of mucosal morphology in Barrett's esophagus based on three criteria: regularity of mucosal pattern, regularity of vascular pattern, and presence of abnormal blood vessels. We aimed to evaluate the interobserver agreement with the proposed mucosal morphology classification and to assess the additional value of narrow band imaging (NBI) over high resolution white light endoscopy (HR-WLE).

PATIENTS AND METHODS

Five international experts in the field of Barrett's imaging and seven community endoscopists with no expertise in this field independently evaluated magnified still images from 50 areas, obtained with HR-WLE and NBI, in Barrett's esophagus patients. Visual analogue scales (VAS) were used for scoring imaging quality. Interobserver agreement for mucosal morphology and yield for identifying early neoplasia were assessed.

RESULTS

Imaging qualities of NBI were rated more highly than HR-WLE, when evaluated separately as well as in a side-by-side comparison. The interobserver agreement ranged from 0.40 to 0.56 and did not significantly differ between expert and non-expert endoscopists. The overall yield for correctly identifying images of early neoplasia was 81 % for HR-WLE, 72 % for NBI and 83 % for HR-WLE + NBI, with no significant difference between experts and non-experts.

CONCLUSION

Interobserver agreement for the classification of mucosal morphology was moderate. Although NBI was rated more highly than HR-WLE for imaging quality, this did not result in improved interobserver agreement or increased yield for identifying early neoplasia in Barrett's esophagus. This applied to non-expert as well as expert endoscopists.

Primary sclerosing cholangitis: a clinical review

Primary sclerosing cholangitis (PSC) is a cholestatic liver disease characterized by fibro-obliterative inflammation of the entire biliary tree. It is a slowly progressive disease with an undulating course, resulting in terminal biliary cirrhosis after a median period of about 12 years after diagnosis. The etiology of the disease is unknown and there is no effective therapy that can halt disease progression. Around 8% of PSC patients develop cholangiocarcinoma, which, by the time it is diagnosed, cannot be treated curatively. The purpose of this article is to review the current knowledge about primary sclerosing cholangitis and to speculate on future strategies to address the issues of etiology and therapy.