Vedolizumab lowers risk of severe CDI in patients with ulcerative colitis

Treatment with vedolizumab is associated with a reduced adjusted risk of severe Clostridioides difficile infection (CDI), but not total CDI, in patients with ulcerative colitis (UC), reports a study. Additionally, cytomegalovirus colitis (CMVC) is not seen in those who initiated vedolizumab.

“Immunosuppression is a risk factor for gastrointestinal infections including CDI and CMVC among patients with UC,” the authors said. “[H]owever, the risk according to the biological class is poorly understood.”

A total of 805 adults with UC involving the initiation of vedolizumab or antitumour necrosis factor-α (anti-TNFα) agents from 1 June 2014 to 31 December 2020 were included in this retrospective cohort study, which was conducted at a large academic health system.

First CDI or CMVC following biological initiation was the primary outcome for both CDI and CMVC analyses, while severe CDI (>10,000 white blood cells or serum creatinine >1.5 mg/dL) served as a secondary outcome for the CDI analysis. Independent variables assessed were demographics and UC history or severity factors.

The authors assessed the risk of CDI by biological group via inverse probability of treatment weighted Cox regression. They only reported CMVC descriptively due to few outcomes.

Of the patients with UC, 195 initiated vedolizumab and 610 anti-TNFα agents. Over 1,436 patient-years, 43 CDIs and 11 severe CDIs were documented.

No association was observed between CDI and vedolizumab relative to anti-TNFα (hazard ratio [HR], 0.33, 95 percent confidence interval [CI], 0.05‒2.03). However, vedolizumab treatment resulted in a significantly lower risk of severe CDI when compared with anti-TNFα (HR, 0.10, 95 percent CI, 0.01‒0.76).

Notably, five cases of CMVC were observed, all of which were in the anti-TNFα group.

“These findings may provide reassurance regarding the use of vedolizumab when also considering the risk of gastrointestinal infections,” the authors said.