Study of the Golimumab Exposure-Response Relationship Using Serum Trough Levels

The study will involve two study groups designed to offer insights into the pharmacokinetics of golimumab during induction and maintenance therapy:

Cohort 1: Patients commencing golimumab induction therapy will be included in a prospective, observational study.

Cohort 2: Patients receiving golimumab maintenance therapy will be included in a cross-sectional, observational study.

Primary objective: To define a week 6 serum golimumab concentration that predicts response at week 14.

Secondary objective: To define serum golimumab concentrations at weeks 6, 10 and 14 that predict response at each time point, respectively and at week 14.

Exploratory objectives:

Correlations between serum golimumab concentrations and novel disease activity indices (PRO2), biochemical markers of disease activity (CRP, faecal calprotectin) and quality of life indices (IBD-Q and IBD-Control).

Correlations between the presence of anti-golimumab antibodies, serum golimumab concentrations and UC disease activity.

This study will also generate data that can be used to validate a commercially available golimumab assay as well as a novel patient reported outcome (PRO) assessment of clinical UC disease activity.

Inclusion criteria

for cohort 1:

• Aged 18 years or over
• Moderate-to-severe UC, defined as:

SCCAI > 5 and, i. A raised fecal calprotectin (> 59 μg/g) or, ii. A raised CRP (> 5 mg/L) or, iii. Endoscopic disease activity Mayo 2 or above, Evaluated within 4 weeks of study enrollment

• Commencing golimumab treatment
• Written informed consent to participate
• Sufficient English language skills to understand the patient information sheet and consent form

Inclusion criteria

for cohort 2:

• Aged 18 years or over
• Receiving golimumab treatment for UC for over 18 weeks (6 injections)
• Written informed consent to participate
• Sufficient English language skills to understand the patient information sheet and consent form

Exclusion criteria

(cohort 1 only):

• Contra-indication to golimumab: tuberculosis or severe infections
• Imminent need for colectomy (i.e. colectomy is being planned)
• Previous primary non-response to anti-TNF therapy in the opinion of the investigator
• Previous treatment with more than one anti-TNF therapy (excluding golimumab)