No Improved Outcomes With Therapeutic Drug Monitoring in IBD Treatment

Proactive therapeutic drug monitoring had little clinical benefit for patients with inflammatory bowel disease (IBD) receiving tumor necrosis factor (TNF)-a antagonists, according to study results published in Gastroenterology.

Researchers conducted a systematic review and meta-analysis, searching publication databases through February 2022 for randomized controlled trials of TNF-a antagonist interventions for IBD that used therapeutic drug monitoring or biologic dose adjustments.

Of 5462 articles identified, researchers included 9 trials in the analysis. Six studies investigated infliximab and 3, adalimumab. The target trough concentration was greater than 3 mg/ml for infliximab and either greater than 5 or greater than 10 mg/ml for adalimumab.

Eight of the trials were conducted among adult patient populations and 1 study recruited pediatric patients. The patient populations were 29% to 65% female, 5% to 50% were on concomitant immunomodulators, and all but 2 trials recruited patients with long-standing disease.

Proactive therapeutic drug monitoring was no more effective than conventional management at 1 year (risk ratio [RR], 0.96; 95% CI, 0.81-1.13; I²=36%). Similar findings were observed when stratifying patients by Crohn disease (CD; RR, 0.87; 95% CI, 0.66-1.15; I²=48%), ulcerative colitis (UC; RR, 0.88; 95% CI, 0.72-1.07; I²=3%), receiving maintenance therapy (RR, 0.94; 95% CI, 0.78-1.13), induction therapy (RR, 1.15; 95% CI, 0.73-1.80), infliximab (RR, 0.97; 95% CI, 0.76-1.24), or adalimumab (RR, 0.93; 95% CI, 0.72-1.20).

Similarly, proactive therapeutic drug monitoring was no more effective than reactive therapeutic drug monitoring (RR, 0.99; 95% CI, 0.78-1.25; I², 48%) in studies that did not allow for dose escalation regardless of disease activity (RR, 0.88; 95% CI, 0.73-1.07; I², 0%) or among patients that had undergone therapeutic drug monitoring prior to randomization (RR, 1.04; 95% CI, 0.88-1.22; I²=15%).

No significant effects were observed for age (P=.58), remission status at baseline (P =.33), concomitant use of immunomodulators (P =.30), disease duration (P =.23), sex (P =.19), proportion of patients with CD (P =.17), or the proportion of patients with prior therapeutic drug monitoring (P =.11).

Patients who received proactive therapeutic drug monitoring were more likely to have dose escalation (RR, 1.56; 95% CI, 1.25-1.94; I²=44%).

Study limitations included differences among patients in the selected trials, such as the proportion of patients who underwent previous optimization therapy, limited data on patients who achieved endoscopic and/or biologic remission, and inconsistent reporting on potential harms from proactive therapeutic drug monitoring.

“We observed no benefit of proactive [therapeutic drug monitoring] compared with conventional management, in achieving and/or maintaining clinical remission in patients with IBD,” the study authors wrote. “We cannot exclude the possibility of benefit in disease subtypes not represented in these RCT populations.”

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.

Reference

Nguyen NH, Solitano V, Vuyyuru SK, et al. Proactive therapeutic drug monitoring vs. conventional management for inflammatory bowel diseases: A systematic review and meta-analysis. Gastroenterology. Published online June 23, 2022. doi:10.1053/j.gastro.2022.06.052