Real-World Drug Retention and Safety of Ustekinumab in Patients With Inflammatory Bowel Disease in Qatar: A Retrospective Cohort Study

Introduction: Inflammatory bowel disease (IBD), encompassing Crohn's disease (CD) and ulcerative colitis (UC), is an increasingly recognized condition in the Middle East and North Africa (MENA) region, yet real-world data on advanced therapies from this population remain scarce. Ustekinumab, a fully human monoclonal antibody targeting the shared p40 subunit of interleukin-12 and interleukin-23, has demonstrated efficacy and safety in pivotal randomized controlled trials for both CD and UC. However, its real-world performance in MENA populations has not been well characterized. This study aimed to evaluate the real-world drug retention, safety profile, and predictors of treatment discontinuation of ustekinumab in patients with IBD at two major referral centers in Qatar. Methods: This was a retrospective, observational cohort study conducted at two IBD referral centers in Qatar (the Ambulatory Care Center and Al Khor Hospital, Hamad Medical Corporation). Adult patients (≥18 years) with a confirmed diagnosis of CD or UC who received at least one induction dose of ustekinumab were included. The primary outcome was drug retention at 6, 12, and 24 months. Secondary outcomes included the safety profile. The study was approved by the Medical Research Committee of Hamad Medical Corporation (MRC-01-25-1395). Results: A total of 345 episodes were included (216 CD, 129 UC). Overall retention at 6, 12, and 24 months was 92.2%, 83.9%, and 77.8%, respectively. CD exceeded UC at all time points; the difference reached statistical significance at six months (95.4% vs. 86.8%; p = 0.011) but attenuated at 12 months (86.5% vs. 79.5%; p = 0.163) and 24 months (81.0% vs. 72.4%; p = 0.087). Discontinuation occurred in 79 episodes (22.9%); primary non-response (10.7%) and secondary loss of response (10.1%) were the main causes. Adverse events were documented in 14 episodes (4.1%); serious adverse events in 5 (1.4%). No malignancies or deaths were recorded. Shorter pre-treatment disease duration was a consistent predictor of discontinuation across all time points (6 months: p = 0.046; 12 months: p = 0.028; 24 months: p = 0.045). Disease type also met the significance threshold at six months (p = 0.011), with patients with UC demonstrating higher early discontinuation rates than those with CD. Conclusions: In this retrospective cohort study, ustekinumab demonstrated high drug retention and an acceptable safety profile in a predominantly Arab IBD population in Qatar. Shorter disease duration prior to ustekinumab initiation was associated with treatment discontinuation across multiple time points, while patients with CD showed higher retention than those with UC at six months (p = 0.011). These findings suggest that disease type and timing of biologic initiation may be associated with ustekinumab persistence in this population. Further prospective studies are needed to confirm these observations in MENA populations with IBD.