High Clinical Remission, Treatment Persistence With Adalimumab Biosimilar in Pediatric IBD

A real-world study of the use of adalimumab biosimilars in pediatric inflammatory bowel disease (IBD) in Sicily found “high rates” of clinical remission and treatment persistence, and no unexpected safety concerns.

At week 52, 72% of patients were in clinical remission, 10% of patients had experienced adverse events, all of which were consistent with the safety profile of adalimumab, and treatment persistence was 85% at 1 and 2 years. The investigators also found that patients with a longer duration of disease were more likely to discontinue treatment.

The anti-tumor necrosis factor (TNF)-α biologics adalimumab and infliximab are approved for the treatment of IBD, which includes Crohn disease (CD) and ulcerative colitis (UC). However, there are high costs associated with biologic therapy, the authors said. In Europe, the patent for the reference adalimumab product (Humira) expired in October 2018, and the first biosimilar (ABP 501) became available in February 2019. According to the authors, the use of adalimumab biosimilars in IBD is increasing, but real-world studies have been limited to adult populations, and pediatric data are “limited.”

Their study assessed effectiveness and safety of adalimumab biosimilars in pediatric patients with IBD. All pediatric patients from the Sicilian Network for Inflammatory Bowel Disease cohort, a registry that includes patients from 16 centers in Sicily, who were treated with adalimumab biosimilars between 2019 and 2021 were included. There were 41 patients, including 30 naïve to TNF inhibitors, 9 who switched from the reference product, and 2 who switched multiple times between biosimilars. The median follow-up time was 11 months.

Most patients (n = 39; 95%) had CD, 1 had UC, and 1 had unclassified IBD. The authors noted that adalimumab was approved for use in pediatric CD in 2012, however it has not yet been approved for pediatric UC, and current treatment guidelines recommend considering adalimumab only in cases of loss of response or intolerance to infliximab. The patient with UC began adalimumab therapy because of an intolerance to infliximab. The 9 patients who switched from the originator were switched while in remission. The 2 patients who switched multiple times between biosimilars did so because of local availability. The adalimumab biosimilars used were ABP501 (Amgevita) in 38 patients and GP2017 (Hyrimoz) in 5 patients.

The investigators assessed remission rates at weeks 14 and 52, treatment persistence, and adverse events, as well as factors associated with clinical remission and treatment persistence. At week 14, 29 patients (71%) achieved clinical remission, 8 (19.5%) had a partial response, and 2 patients had discontinued therapy, 1 due to primary failure, and 1 due to adverse events. One patient had required dose escalation. There were no significant differences in clinical scores, C-reactive protein (CRP), erythrocyte sedimentation rate, hemoglobin, or fecal calprotectin between baseline and 14 weeks.

Twenty-five patients (61%) continued treatment through week 52, and 18 of 25 (72%) were in clinical remission at 52 weeks. Of these 18, 16 had maintained remission from week 14. Two patients (8%) had a partial response, and 7 (17%) required treatment escalation. The authors said that clinical scores and laboratory parameters were “similar” between baseline, week 14, and week 52.

The investigators also analyzed predictive factors associated with remission and treatment persistence. They found that remission at week 14 occurred more frequently in patients with shorter disease duration. Other factors analyzed, such as gender, age at diagnosis, laboratory values, and previous anti-TNF therapy were not associated with remission.

At week 52, patients who had not switched from the originator and those who had lower CRP levels at baseline were more likely to achieve remission. Treatment persistence was 85% at 1 year and remained at 85% at 2 years. Longer disease duration was significantly associated with the risk of treatment discontinuation. The authors wrote that their finding of an inverse association between disease duration and both clinical remission and treatment persistence is “of clinical relevance as it confirms the relevant role of early and timely treatment for better outcomes and treatment response.”

Four patients (10%) experienced adverse events: 2 cases of psoriasiform dermatitis, 1 acute injection reaction, and 1 infection. In 2 cases, adverse events led to treatment discontinuation. The authors noted that the incidence rate and characteristics of adverse events were consistent with those described for adalimumab products in adults, “with no unexpected serious outcomes.”

To the authors’ knowledge, theirs is the first study to evaluate real-world effectiveness and safety of adalimumab biosimilars in pediatric IBD. They commented that their results demonstrate “high rates of treatment persistence and a low frequency of non-serious side effects.” Adalimumab biosimilar therapy “seems to be effective” in pediatric IBD, they wrote, adding that more research will be necessary to validate their findings and investigate real-world pharmacokinetics and immunogenicity in pediatric populations.

Reference

Dipasquale V, Pellegrino S, Ventimiglia M, et al. adalimumab biosimilar in pediatric inflammatory bowel disease: A retrospective study from the Sicilian Network for Inflammatory Bowel Disease (SN-IBD). Healthcare. 2024;12(3):404. doi:10.3390/healthcare12030404