Abstract Background Ustekinumab is approved for treatment of active Crohn’s Disease (CD) and Ulcerative Colitis (UC) with a more favourable safety profile to anti-TNF therapy however it is still used with caution in the elderly and those with comorbidities. We present our data on safety and efficacy of Ustekinumab in our IBD population including consideration of age and existing medical conditions. Methods Clinical data on all IBD patients treated with Ustekinumab within our population between, 2016 and, 2021 were retrospectively collected from electronic records. This included baseline characteristics, diagnosis, previous medical and surgical history, comorbidities, clinical response, endoscopic response and adverse events (AEs). Results 120 (M=57, F=63) patients were identified, 98 CD, 17 UC and, 5 IBDU with a median follow up of, 13.9 months (IQR, 3–20.5) The median age of starting Ustekinumab was, 35.5 years (16–81) with, 65% (78/120) previously treated with two or more biologics suggestive of refractory disease. Clinical response was achieved in, 18.0% (16/89) of patients at, 8 weeks, 39.3% (24/61) at, 24 weeks, 42.0% (21/50) at, 1 year and endoscopic response and/or with imaging was seen in, 9/23 (39.1%) at, 24 weeks and, 3/18 (16.7%) at, 1 year. 10% (14/120) were >60 at time of starting Ustekinumab, this group had an average of, 1.4 comorbidities compared to, 0.3 in the <, 60 group (p value -0.00001), 7% (8/, 120) patients had had a prior malignancy (Non-melanoma Skin Ca, 4, Solid organ, 2, melanoma, 1, haematological, 1) and, 5 of these were in the >60 group with a median of, 10 years (IQR, 5–11) since being cured and no episodes of recurrence, with, 1 patient developing a malignancy post Ustekinumab. Adverse events (AEs) were seen in, 5.8% (7/120) of patients and a serious adverse event (SAE) in, 5% (6/120), this included, 4 patients in the <60 age group requiring admission for Intravenous antibiotics vs, 1 in the >, 60 age group (p value, 0.57). Conclusion This study contributes to the real-world data being presented regarding Ustekinumab. The efficacy demonstrated in clinical response is comparable to previous studies, the majority of patients having already been treated with two or more biologics. We have demonstrated a favourable safety profile in the over, 60 age group who had a greater number of comorbidities and a higher rate of previous malignancy. With an ageing IBD population the safety and efficacy of Biologics in the older age groups need to be further examined.