Outcome of Reverse Switching From CT-P13 to Originator Infliximab in Patients With Inflammatory Bowel Disease

BACKGROUND: Patients suffering from inflammatory bowel diseases (IBD) and treated with originator infliximab are increasingly being switched to biosimilars. Some patients, however, are "reverse switched" to treatment with the originator. Here we assess the prevalence of reverse switching, including its indication and outcomes. METHODS: In this retrospective multicenter cohort study, data on patients with IBD from 9 hospitals in the Netherlands were collected. All adult patients with IBD were included if they previously had been switched from originator infliximab to the biosimilar CT-P13 and had a follow-up time of at least 52 weeks after the initial switch. The reasons for reverse switching were categorized into worsening gastrointestinal symptoms, adverse effects, or loss of response to CT-P13. Drug persistence was analyzed through survival analyses. RESULTS: A total of 758 patients with IBD were identified. Reverse switching was observed in 75 patients (9.9%). Patients with reverse switching were predominantly female (70.7%). Gastrointestinal symptoms (25.5%) and dermatological symptoms (21.8%) were the most commonly reported reasons for reverse switching. In 9 patients (12.0%), loss of response to CT-P13 was the reason for reverse switching. Improvement of reported symptoms was seen in 73.3% of patients after reverse switching and 7 out of 9 patients (77.8%) with loss of response regained response. Infliximab persistence was equal between patients who were reverse-switched and those who were maintained on CT-P13. CONCLUSIONS: Reverse switching occurred in 9.9% of patients, predominantly for biosimilar-attributed adverse effects. Switching back to originator infliximab seems effective in patients who experience adverse effects, worsening gastrointestinal symptoms, or loss of response after switching from originator infliximab to CT-P13

Exposure to thioguanine during 117 pregnancies in women with inflammatory bowel disease

BACKGROUND: Safety of thioguanine in pregnant patients with inflammatory bowel disease (IBD) is sparsely recorded. This study was aimed to document the safety of thioguanine during pregnancy and in birth. METHODS: In this multicenter case series, IBD patients treated with thioguanine during pregnancy were included. Data regarding disease and medication history, pregnancy course, obstetric complications and neonatal outcomes were collected. RESULTS: Data on 117 thioguanine-exposed pregnancies in 99 women were collected. Most (78%) had Crohn's disease and the mean age at delivery was 31 years. In eighteen pregnancies (15%) IBD flared. Obstetric and infectious complications were seen in 15% (n=17) and 7% (n=8) of pregnancies, respectively. Ten pregnancies (8.5%) resulted in a first trimester miscarriage and one in a stillbirth at 22 weeks gestational age. Congenital abnormalities were observed in one induced abortion (trisomy 21) and in one of the live-born children (cleft palate) . In total 109 neonates were born from 101 singleton pregnancies and 4 twin pregnancies. In the singleton pregnancies, ten children were born prematurely and ten were born small for gestational age. Screening for myelosuppresion was performed in sixteen neonates (14.7%); two had anemia in umbilical cord blood. All outcomes were comparable to either the general Dutch population or to data from 3 Dutch cohort studies on the use of conventional thiopurines in pregnant IBD patients. CONCLUSION: In this large case series the use of thioguanine during pregnancy is not associated in excess with adverse maternal or neonatal outcomes