Skip to main content
OpenTrials
Active, Not Recruiting

NCT Number: NCT03765450

Pharmacokinetics of IFX and TNF Concentrations in Serum, Stool, and Colonic Mucosa in Acute Severe Ulcerative Colitis

This is an open-label, prospective, observational study with the primary objective to characterize the pharmacokinetics of infliximab in patients with Acute Severe Ulcerative Colitis.

Active, Not Recruiting

This study is active but is not currently recruiting participants.

Notify Me

Key information

Age range

18 year and older

Sex eligibility

All sexes

Study type

Observational

Primary location

Mount Sinai Hospital, Toronto, Ontario, Canada

Loading trial locations.

About this study

In Acute Severe Ulcerative Colitis (ASUC), drug exposure may be affected by intestinal protein loss leading to hypoalbuminemia and rapid clearance of infliximab (IFX). Importantly, 2 studies have associated the loss of IFX in stool with poor outcomes. Multiple observational studies have identified that patients with faster IFX clearance have worse clinical outcomes and higher rates of antidrug antibody formation. To better understand optimal dosing of IFX in ASUC, the pharmacokinetics of IFX in association with outcomes must be better defined in this setting.

Who can participate

Healthy volunteers accepted: No

Only the study team can determine whether someone qualifies for participation.

Inclusion criteria

  • Present to hospital with ASUC based on Truelove and Witts criteria,33 defined as the presence of more than 6 bloody stools per day along with any 1 of the following: tachycardia > 90 beats per minute, fever > 37.8 °C, hemoglobin < 10.5 g/dL, and erythrocyte sedimentation rate (ESR) > 30 mm/h (or CRP > 30 mg/L [high-sensitivity CRP > 300 mg/L]) is a suitable surrogate if ESR is not available1).
  • Have a partial MCS > 7.
  • Have a Mayo Clinic ES ≥ 2 with disease extending 15 cm or more beyond the anal verge.
  • Require rescue inpatient IFX infusion as part of routine care. Note, the IFX treatment regimen is not defined by this protocol and any dosage regimen is acceptable for the purposes of this study, such as standard or accelerated induction regimens.
  • Be able to speak English and participate fully in all aspects of this clinical trial.
  • Provide written informed consent.

Exclusion criteria

  • A known history of being positive for anti-IFX antibodies.
  • Have a serious active infection, active malignancy, or any other known condition contraindicated with infliximab therapy, according to current prescribing information.
  • Serious underlying disease other than ASUC, or other physical or psychosocial condition that, in the opinion of the investigator, may interfere with the subject's ability to participate fully in the study.
  • Prior enrollment in the current study.

Treatment and study plan

Infliximab

Drug

Patients will receive infliximab at the discretion of their physician as part of standard of care.

Primary outcomes

  1. Inter-compartmental Difference in Infliximab Concentration

    Time frame: 22 weeks

    Infliximab population pharmacokinetics

Secondary outcomes

  1. Change in Proteome

    Time frame: 22 weeks

    Change in Proteomics before and after therapy

  2. Change in Transcriptome

    Time frame: 22 weeks

    Change in Transcriptomics before and after therapy

  3. Change in Robarts Histopathologic Index

    Time frame: 22 weeks

    Change in Robarts Histopathologic Index before and after therapy The RHI consists of 4 histological items (extent of chronic inflammatory cell infiltration, neutrophils in the lamina propria, neutrophils in the epithelium, and erosions and ulceration) scored from 0 to 3 and multiplied by a weighting factor. The total RHI score is calculated by summing the weighted scores of the histological items, with total scores ranging from 0 (no disease activity) to 33 (severe disease activity).

  4. Change in Mayo Clinic Endoscopic Score

    Time frame: 22 weeks

    Change in Mayo Clinic Endoscopic Score before and after therapy The Mayo Clinic score (MCS) scores 4 variables (stool frequency, rectal bleeding, a physician's global assessment and endoscopic findings with flexible sigmoidoscopy). The endoscopic component of the MCS assesses disease activity on a 4-point scale (0-3 points), with higher scores representing more severe disease activity. Mucosal healing is often defined as an endoscopy score of 0 or 1.

    Normal or inactive disease = 0 Mild disease (erythema, decreased vascular pattern, mild friability) = 1 Moderate disease (marked erythema, absent vascular pattern, friability, erosions) = 2 Severe (spontaneous bleeding, ulceration) = 3

Sponsors and collaborators

Lead sponsor

Alimentiv Inc.

Other

Registry information

Official study title

Pharmacokinetics of Infliximab and Tumor Necrosis Factor Concentrations in Serum, Stool, and Colonic Mucosa in Acute Severe Ulcerative Colitis

Acronym: PROTOS

Important dates

Study start
2018
Primary completion
2023
Study completion
2027
First posted
Dec 5, 2018
Registry last updated
Jun 2, 2026

OpenTrials presents study information sourced from ClinicalTrials.gov. The official registry record should be consulted for the latest information.

View the official ClinicalTrials.gov record (opens in a new tab)

This listing is for discovery and informational purposes only. It is not medical advice, does not guarantee that a study is recruiting, and does not determine eligibility. Contact the study team and a qualified healthcare professional when considering participation.

Published trials that share one or more normalized conditions with this study.