Comparative efficacy and safety of Ustekinumab in Crohn's disease and Ulcerative Colitis: retrospective study of real-life

Background & aims: Ustekinumab is an effective biological treatment for patients with Crohn's disease (CD) and Ulcerative Colitis (UC). Real-world effectiveness and safety studies are warranted especially in the bio-experienced inflammatory bowel disease (IBD) population and in patients with UC vs CD, where the evidence is still limited. The aim of our study was to assess clinical, biochemical and endoscopic remission as well as the safety profile of Ustekinumab after 3 months, 6 months and 1 year. Methods: all consecutive moderate-to-severe IBD patients who started Ustekinumab from 01/01/2019 to 12/04/2023 were included. We collected demographic and clinical data, including disease location and behavior, previous treatments, previous surgery, concomitant medications, smoke habit. In addition, data on partial Mayo (p-Mayo) Score, endoscopic Mayo (e-Mayo) Score, Harvey-Bradshaw Index (HBI), SES-CD Score, Rutgeerts Score, fecal calprotectin were collected. Serious infections and adverse events were defined as those requiring hospitalization or treatment discontinuation. Continuous and categorical variables were expressed as mean with standard deviation (SD) and frequency with percentages respectively. Comparisons among variables were conducted using one-way ANOVA and Chi-square. All data analyses were performed with SPSS Version 26.0 statistic software package. Results: overall, 131 IBD (84 with CD and 47 with UC) adult patients were enrolled. Among the patients included, all CD patients and 89.36% (42/47) UC patients were bio-experienced; most of them had previous experience with Infliximab (80,95% CD patients; 72,34% UC patients). Ten CD (11,90%) and 19 UC (40,42%) patients were taking immunosuppressants at baseline; 53 CD patients (63,10%) and 3 UC patients (3,75%) had undergone bowel resective surgery. After 1 year, 27% of CD patients and 38% of UC patients obtained a clinical response (p=0,423), while 64% of CD and 22% of UC patients obtained clinical remission; after 12 months 100% of CD patients and 50% of UC were in steroid-free clinical remission (p=0,02). In addition, 51,6% of CD patients and 20% of UC patients reached biochemical remission (p=0,028), while 27,87% of CD patients and 20% of UC patients obtained an endoscopic remission (p=0,583). 44% of CD patients and 7% of UC patients found endoscopic response. A total of 15 adverse events occurred during follow-up in both groups. The majority of them were related to infection (9/15) and 4 were classified as serious adverse events. Serious adverse reactions occurred only in CD patients. Conclusions: Ustekinumab was an effective therapy in both patients with CD and UC. However, CD patients had better clinical and endoscopic outcomes than UC subjects, but biochemical remission did not differ between the two groups. Ustekinumab was safe and well-tolerated in the short and in the long term, with only 4 severe adverse reactions out of 131 patients in both groups. Infections were the most frequent adverse events encountered.