High Acceptance Levels After Switching to an Adalimumab Biosimilar for IBD

A French observational study found “high acceptance levels” among patients with inflammatory bowel disease (IBD) offered a switch from the adalimumab reference product to 1 of 5 biosimilars when also given education and tailored guidance. The study found that 92% of patients accepted the switch, and 71% remained on a biosimilar at 12 months.

The most common reason for discontinuing biosimilar treatment was injection site pain. At 12 months, 85% of patients who switched were in clinical remission. The researchers concluded that most patients with IBD receiving the adalimumab originator are open to switching to a biosimilar and “achieve good outcomes.”

About 7 million people worldwide are afflicted with IBD, an immune-mediated inflammatory disease of the gastrointestinal tract which encompasses Crohn disease (CD) and ulcerative colitis (UC). IBD treatment is costly, primarily because of the cost of biologics, including adalimumab, a monoclonal antibody targeting tumor necrosis factor-α.

The study assessed 5 of the adalimumab biosimilars that are available in Europe: Amgevita, Hulio, Hyrimoz, Idacio, and Imraldi. Notably, adalimumab products differ in injection devices, excipients, and injection volumes.

The concerns of patients about biosimilars “remain poorly addressed,” according to the authors, despite recommendations of medical organizations such as the European Crohn’s and Colitis Organisation (ECCO) and accumulating clinical evidence supporting the safety and effectiveness of biosimilars. These concerns could limit patient acceptance and treatment adherence.

The prospective observational study evaluated the acceptance rate of biosimilar switching and factors associated with non-acceptance, as well as biosimilar persistence, clinical outcomes, and patient perceptions at 12 months. The study was conducted at a single hospital in France and included 97 adult patients with IBD who had been treated with the adalimumab reference product for at least 6 weeks. All patients received standardized verbal information about biosimilars from their regular gastroenterologist and a trained nurse assigned to guide their switch process. Patients were offered the option to switch from the reference product to their choice of 5 biosimilars, and were followed for 12 months.

Of the 97 patients, 84 had CD and 13 had UC. The median disease duration was 13 years, and 92 patients (95%) were in clinical remission, defined by Harvey Bradshaw Index of 4 or lower for CD or a Partial Mayo Score of 1 or lower for UC. Seventy-four patients (82%) were in biochemical remission, defined as C-reactive protein (CRP) of 5 mg/L or lower.

While 89 patients (92%) accepted a switch to a biosimilar, only 45% reported having no concerns about biosimilars. The factors potentially associated with patient acceptance of biosimilars considered by researchers included sex, education level, flu vaccine adherence, previous biologic therapy, disease duration, and duration of originator therapy. The only factor significantly associated with non-acceptance of a biosimilar was a poor opinion of generic drugs.

Persistence with the initial biosimilar was 69% at 6 months and 60% at 12 months, and the overall persistence rates (non-discontinuation of biosimilar therapy) were 77% and 71%. Thirty-seven of the 89 patients who switched discontinued their first biosimilar: 22 switched back to the reference product, 3 discontinued adalimumab therapy, 12 switched to another biosimilar, and 2 were lost to follow-up. The most frequent causes of discontinuation were injection site pain (25%), loss of efficacy (7%), and difficulties with a new injection device (4.5%). Four patients (13%) discontinued due to abdominal pain, which was considered a nocebo effect because of the lack of objective disease activity.

At baseline, 84 (94%) of the 89 patients who accepted the switch were in clinical remission, 79 (89%) were in remission at 6 months, and 76 (85%) at 12 months. Sixty eight of 82 (83%) switched patients with CRP data were in biochemical remission at baseline, 48 (83%) of 58 at 6 months, and 42 (86%) of 49 at 12 months. One of the 8 patients who declined to switch was lost to follow-up, and the other seven remained on the originator at 12 months and remained in clinical and biochemical remission.

Of the 38 patients who completed the questionnaire at the end of the study, 66% reported a positive experience with switching to a biosimilar, 2.6% reported a positive impact on their disease, and 16% reported a negative impact.

The results suggest having a poor opinion of generics could lead to not accepting a switch to a biosimilar. The authors said the high rates of clinical and biochemical remission they observed at 12 months suggest that switching did not have a negative impact on disease control. Additionally, the majority of patients who switched and were surveyed reported a positive experience. They commented that continuous patient education and healthcare providers addressing patients’ individual concerns, “is crucial for improving overall satisfaction with biosimilars and maximizing their benefits.”

Reference

D’Abbundo G, Nachury M, Wartski A, et al. Switch acceptance and persistence of adalimumab biosimilars in IBD patients: a prospective observational study. Therapeutic Advances in Gastroenterology. 2025;18. doi:10.1177/17562848251332025