P223 C-reactive protein improvement after vedolizumab induction phase is associated with remission after 6 months of treatment in ulcerative colitis patients
Zezos P.*1, Kabakchiev B.2, Weizman A.V.1, Nguyen G.C.1, Narula N.1, Croitoru K.1, Steinhart A.H.1, Silverberg M.S.1
1Mount Sinai Hospital, University of Toronto, Division of Gastroenterology, Toronto, Canada 2Mount Sinai Hospital, Samuel Lunenfeld Research Institute, Toronto, Canada
Vedolizumab, a gut-selective anti-integrin inhibitor is a biologic agent indicated for ulcerative colitis (UC) treatment. We retrospectively investigated whether improvement of serum C-reactive protein (CRP) levels, after the first 3 infusions of vedolizumab (induction phase) predicts responsiveness at 6 months of therapy.
Adult UC patients followed at a tertiary IBD center and treated with vedolizumab were included. Cumulative rates of clinical remission (CR, partial Mayo score ≤2 with a bleeding subscore 0) and steroid-free clinical remission (SFCR) were assessed at 3 and 6 months. Responses were calculated using nonresponder imputation. Mann-Whitney U-test was used for unpaired samples and Wilcoxon signed-rank test for paired samples to analyze for differences in CRP levels between patients in remission and in no remission at 6 months of continuous vedolizumab treatment.
Fifty-seven UC patients (Table 1) were analyzed. Two thirds had prior anti-TNF treatment exposure and two thirds had pancolitis. All 57 patients completed 3 vedolizumab infusions by week 6 and 49 completed 5 infusions by week 22. Following 3 infusions, CR and SFCR were 37% (21/57) and 30% (17/57) and at 6 months the cumulative rates of CR and SFCR were 49% (28/57) and 44% (25/57) respectively (Table 1). Patients in remission at 6 months had significantly lower baseline median CRP levels compared to those not in remission (3 versus 12 respectively, p=0.005). Low CRP levels at baseline were not associated with steroid use. Only patients in remission at 6 months had a significant reduction of median CRP levels after 3 vedolizumab infusions as compared to median baseline levels (z=3.225, p=0.001, Figure 1). Nine out 36 patients who were non- responders after the induction phase achieved clinical remission at 6 months. Their (n=9) median CRP levels at baseline and after 3 infusions were significantly lower compared to the non-responders (n=27) (3 versus 13; z=2.028, exact p=0.043 and 2 versus 10, z=2.093, exact p=0.035, respectively).
Low baseline CRP levels and further reduction of the levels after the induction phase of vedolizumab treatment are associated with clinical remission at 6 months. A decrease in CRP following vedolizumab induction may be used to predict those patients who will be in clinical remission at 6 months.