Combination therapy with vedolizumab and thiopurines is associated with lower treatment failure compared with vedolizumab monotherapy in patients with Crohn disease (CD), but not in those with ulcerative colitis (UC), according to a study in Gut.
The findings are based on data from 2 US health care claims databases — IBM MarketScan (MarketScan) 2009-2018 and Optum’s deidentified Clinformatics Data Mart Database (Optum) 2009-2020 — as well as the French administrative health database, Système National des Données de Santé (SNDS) 2009-2018.
The observational study followed 2 clinical trials that compared the effectiveness of vedolizumab and thiopurines combined vs vedolizumab monotherapy in patients with CD and UC and follows the general approach used in the SONIC and SUCCESS trials.
Eligible participants were adults (≥18 years) with at least 1 visit for CD and UC based on the International Classification of Diseases 9 (ICD-9) or 10 (ICD-10) revision codes. Patients who began vedolizumab therapy after January 1, 2014, were considered for inclusion.
After propensity score (PS) matching, the cohorts included 804 pairs of patients with CD and 1088 pairs of patients with UC.
Among the patients with CD, treatment failure at week 26 occurred in 236 (29.3%) and 376 (34.3%) patients who initiated combination therapy and vedolizumab monotherapy, respectively. Study participants who began combination therapy had a 15% decreased risk for treatment failure vs those who initiated infliximab monotherapy (risk ratio [RR], 0.85; 95% CI, 0.74-0.98). The findings were comparable in the 3 databases (RR, 0.87; 95% CI, 0.68-1.12 in MarketScan; RR, 0.88; 95% CI, 0.64-1.21 in Optum; and RR, 0.83; 95% CI, 0.68-0.98 in SNDS).
In the PS-matched cohort for UC, 236 (21.7%) and 263 (24.2%) patients were in treatment failure at week 16 after beginning combination therapy and vedolizumab monotherapy, respectively. Little difference was observed in the risk for treatment failure between combination therapy and vedolizumab monotherapy (RR, 0.90; 95% CI, 0.77-1.05).
The rates of serious infections and hospitalizations not related to inflammatory bowel disease (IBD) were not different between the 2 treatment groups, and no meaningful variation was found in treatment failure risks across subgroups.
Among several study limitations, the investigators were unable to exclude prevalent users of thiopurines in the combination therapy group. Also, endoscopic and histological data were not available, and residual confounding by these factors could not be ruled out.
“…[T]his study based on  large population-based cohorts of patients with IBD in both the [US] and France provides evidence that combination therapy with vedolizumab and thiopurines is more effective compared with vedolizumab monotherapy in patients with CD and possibly less so with UC,” the researchers wrote. “These findings will help guide clinical decision-making in patients with IBD starting vedolizumab.”
Disclosure: Some study authors declared affiliations with biotech, pharmaceutical, and/or device companies. Please see the original reference for a full list of authors’ disclosures.
Kirchgesner J, Desai RJ, Schneeweiss MC, Beaugerie L, Schneeweiss S, Kim SC. Decreased risk of treatment failure with vedolizumab and thiopurines combined compared with vedolizumab monotherapy in Crohn’s disease. Gut. Published online April 6, 2022. doi:10.1136/gutjnl-2022-327002