Pregnant women with rheumatoid arthritis (RA) and juvenile idiopathic arthritis (JIA) who discontinue a tumor necrosis factor inhibitor (TNFi) prior to 20 weeks of gestation are not at increased risk for disease deterioration, according to a study recently published in Arthritis & Rheumatology. Discontinuation was feasible among women with well-controlled disease at the start of pregnancy.
This study included 490 women with RA (n=397) and JIA (n=93) enrolled in the Organization of Teratology Information Specialists (OTIS) Autoimmune Diseases in Pregnancy Project between 2005 and 2017. Before 20 and 32 weeks gestation, data were collected on disease activity and medication usage. Multivariate and unadjusted analyses were used to examine the relationship between changes in disease activity and either continuation or discontinuation of TNFi. The Wilcoxon signed rank test was used to study change between the baseline and third trimester in outcome measures reported by patients. The effect of either continuing or discontinuing TNFi on minimal clinically important difference and outcomes reported by participants was analyzed using logistic and linear regression models.
A TNFi was used during pregnancy by 323 (65.9%) participants. The majority (41.0%) used a TNFi beyond 20 weeks, while 24.9% discontinued the use of a TNFi before 20 weeks. Of those who continued past 20 weeks, 57.7% continued with TNFi until the end of term, while 42.3% discontinued therapy. The majority of women (72.9%) had low disease activity at baseline. Patient-reported outcome measures at the third trimester did not worsen significantly in association with discontinuing TNFi. Use beyond 20 weeks was associated with improved scores on disease activity at the third trimester in univariate analysis, though this effect was not observed in multivariate analysis.
Limitations to this study included the use of patient-reported outcomes that may have been influenced by the pregnancy itself, evidence of a selected cohort, and a small number of women with JIA.
The study researchers concluded that “we did not find an increased risk of disease deterioration after discontinuation of TNFi before gestational week 20 in women with well-controlled RA and JIA. In case of active disease, the continuation of TNFi beyond gestational week 20 seems reasonable from the standpoint of improved disease activity in the third trimester, which may in turn lead to improved pregnancy outcomes.”
The OTIS Collaborative Research Group reports financial associations with several pharmaceutical companies. For a full list of financial contributions, see the reference.
Förger F, Bandoli G, Luo Y, Robinson L, Johnson DL, Chambers CD. Discontinuing TNF-inhibitors before gestational week 20 in well-controlled rheumatoid arthritis and juvenile arthritis is not associated with a disease worsening in late pregnancy [published online January 21, 2019]. Arthritis Rheumatol. doi: 10.1002/art.40821