P965 Ulcerative proctitis treated with biologics: is it too hard to treat?

Abstract

Abstract Background Patients with ulcerative proctitis are widely considered a challenging population because the reported reduced response rate to conventional medical treatment. On the other hand, data on the role of biological therapies in this specific cohort are currently scarce Methods We retrospectively evaluated all patients with proctitis (defined as the mucosal inflammation of only the rectum with ulcerative colitis confirmed by histology) treated with biologics (infliximab, adalimumab, vedolizumab -VDZ-, ustekinumab -UST) and tofacitinib (TOFA) at four referral centers in the last 5 years. All patients were treated with concomitant topical mesalamine. We included in this study only patients who underwent colonoscopy at baseline and after 52 weeks of treatment, in order to evaluate therapeutic response in terms of mucosal healing (defined as a Mayo Endoscopic Score -MES- <2), besides that clinical remission (defined as a Partial Mayo Score -PMS- <2 without oral or topical corticosteroid therapy). We collect clinical and demographic data, as well as fecal calprotectin (FC) and C-Reactive Protein (CRP) levels at baseline and after the induction of therapy Results Among 64 patients enrolled (age 50.8±16.5 years, 29 [45.3%] women), 33 (51.6%) were treated with anti-TNF), 15 with VDZ, 13 with UST, and 3 with TOFA. Globally, 51 (79.7%) patients achieved clinical remission and 37 (57.8%) patients achieved endoscopic remission at 52 weeks. There were no group differences in age, sex, BMI, disease duration, PMS, MES, drug, or baseline CRP levels between patients achieving or not either clinical or endoscopic remission. Baseline calprotectin levels were lower in patients who achieved endoscopic remission (median [IQ range] 297 [158, 475] versus 442 [230, 1545] µg/mL, p=0.036), but not in those who achieved clinical remission. After the induction phase, lower calprotectin levels were observed in patients achieving clinical (46 [15, 166] versus 553 [72, 1649] µg/mL, p=0.001) and endoscopic remission (38 [15, 112] versus 328 [52, 2171] µg/mL, p=0.0002), compared with non-responders. The effects of post-induction calprotectin levels on clinical remission (β= -0.001, p=0.020) and endoscopic remission (β= -0.007, p=0.006) remained significant in multivariable models adjusted for age, sex, BMI, disease duration, and biological treatment. A cut point of 200 µg/mL post-induction was identified to predict endoscopic remission (sensitivity 92%, specificity 64%, ROC AUC 0.781) Conclusion High rates of clinical and endoscopic remission with biological therapies could be achieved in patients with ulcerative proctitis. Fecal calprotectin levels after the induction of biological therapies seem to predict the therapeutic response in patients with ulcerative proctitis