Continuing anti-TNF therapy in pregnancy appears beneficial for patients with IBD

A French target trial emulation, which refers to the use of observational data to mimic a randomized controlled trial, found that maternal relapse of inflammatory bowel disease (IBD) and premature births were less common when patients continued anti-tumor necrosis factor (anti-TNF) therapy after 24 weeks of pregnancy than when the drugs were discontinued.

Patients with inflammatory bowel disease (IBD) may be able to safely continue anti-tumor necrosis factor (anti-TNF) therapy after 24 weeks of pregnancy, a recent study found.

Researchers used a data from a nationwide French database to perform a target trial emulation between 2010 and 2020 evaluating the benefits and risks of continuing anti-TNF therapy for patients with IBD and their offspring. In a target trial emulation, observational data are used to mimic a randomized controlled trial. IBD was defined as Crohn's disease or ulcerative colitis. European guidelines currently recommend that clinicians consider stopping anti-TNF therapy in patients with sustained IBD remission after 24 weeks of pregnancy, while North American guidelines recommend that therapy continue. The study used inverse probability-weighted marginal models to compare maternal IBD relapse up to six months after pregnancy, adverse pregnancy outcomes, and serious infections in offspring during the first five years of life according to anti-TNF therapy continuation after 24 weeks of pregnancy. Results were published Sept. 27 by Annals of Internal Medicine.

A total of 5,293 pregnancies were included in the study. Anti-TNF treatment was discontinued before 24 weeks for 2,890 participants and continued beyond 24 weeks for 2,403. Continuation of anti-TNF therapy was associated with decreased rates of maternal IBD relapse (35.8% vs. 39.0%; adjusted risk ratio [aRR], 0.93 [95% CI, 0.86 to 0.99]) and prematurity (7.6% vs. 8.9%; aRR, 0.82 [95% CI, 0.68 to 0.99]). Rates of stillbirth (0.4% vs. 0.2%; aRR, 2.16 [95% CI, 0.64 to 7.81]), birth with low weight for gestational age (13.1% vs. 12.9%; aRR, 1.01 [95% CI, 0.88 to 1.17]), and serious infection in offspring (54.2 vs. 50.2 per 1000 person-years; adjusted hazard ratio, 1.08 [95% CI, 0.94 to 1.25]) did not differ by whether anti-TNF therapy was continued.

The authors noted that algorithms rather than clinical data were used to identify patients with IBD, pregnancies, and serious infections and that very preterm births were not studied in the main analysis, among other limitations. “Results of the present target trial emulation suggest that continuation of anti-TNF throughout pregnancy is associated with improved outcomes in regard to maternal IBD activity and prematurity, whereas other pregnancy outcomes and susceptibility to serious infections of the offspring do not seem to be affected,” they wrote. “Therefore, this study favors continuation of anti-TNF throughout pregnancy in women treated for an IBD.”