Background Ustekinumab (UST) is indicated for the treatment of Crohn's disease (CD) and Ulcerative Colitis (UC). Despite having shown clinical effectiveness in the real world, some patients may lose response over time or need a higher dose to achieve it. In this context, UST intravenous (IV) maintenance has been proposed. Objectives The primary endpoint of our study was to evaluate the efficacy and safety of maintenance IV UST treatment in Inflammatory Bowel Disease (IBD) patients who present with partial response or loss of response to subcutaneous (SC) UST. Design We performed a monocentric observational retrospective study including patients with active IBD on maintenance treatment with IV UST. Methods The clinical response and remission was analyzed at week 12, defined as either Harvey-Bradshaw Index ⩽ 4 for CD or partial Mayo Score ⩽ 2 for UC. The reduction of objective markers of disease activity, fecal calprotectin, and C-reactive protein was evaluated. Moreover, UST trough levels were measured pre- and post-UST IV maintenance and any adverse events were assessed. Results We included 23 patients. Clinical remission at week 12 was achieved by 43.5% of the patients. The proportion of patients in clinical response after 12 weeks on UST IV maintenance was 82.6%. After a median follow-up of 9.3 months all patients remained on IV UST maintenance. No adverse events were recorded in any patient for the duration of the study. Conclusions IV UST maintenance treatment was able to recapture response in most of the patients who had lost response to SC maintenance.

中文翻译：

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对皮下给药失去反应的患者进行静脉乌特克单抗维持治疗。

背景 乌司奴单抗 (UST) 适用于治疗克罗恩病 (CD) 和溃疡性结肠炎 (UC)。尽管在现实世界中显示出临床有效性，但一些患者可能会随着时间的推移失去反应或需要更高的剂量才能实现反应。在此背景下，提出了 UST 静脉 (IV) 维持治疗。目的 我们研究的主要终点是评估对皮下 (SC) UST 部分缓解或失去反应的炎症性肠病 (IBD) 患者维持 IV UST 治疗的有效性和安全性。设计 我们进行了一项单中心观察性回顾性研究，包括接受 IV UST 维持治疗的活动性 IBD 患者。方法 在第 12 周对临床反应和缓解进行分析，定义为 CD 的 Harvey-Bradshaw 指数≤ 4 或 UC 的部分 Mayo 评分≤ 2。评估了疾病活动、粪便钙卫蛋白和 C 反应蛋白的客观标志物的减少。此外，在 UST IV 维持前后测量了 UST 谷值水平，并评估了任何不良事件。结果 我们纳入了 23 名患者。43.5% 的患者在第 12 周达到临床缓解。UST IV 维持治疗 12 周后出现临床缓解的患者比例为 82.6%。中位随访 9.3 个月后，所有患者仍接受 IV UST 维持治疗。在研究期间，没有任何患者记录到不良事件。结论 IV UST 维持治疗能够使大多数对 SC 维持失去反应的患者重新获得反应。