Long-term clinical outcomes were similar among patients with Crohn disease (CD) who received originator-adalimumab or after nonmedical switch to adalimumab biosimilar SB5 (SB5-adalimumab), according to study findings published in the Scandinavian Journal of Gastroenterology.
For the analysis, researchers sourced data from the Czech Registry of IBD Patients on Biological and Innovative Therapy, a multicenter registry of patients with inflammatory bowel disease (IBD) who were receiving biologic or innovative therapies in the Czech Republic. Patients with CD treated with 40 mg subcutaneous originator-adalimumab every 2 weeks for more than 3 months were evaluated for clinical outcomes from July 2018 to January 2021. Patients were stratified by whether they remained on originator-adalimumab or switched to SB5-adalimumab for nonmedical reasons. A propensity matching approach was used to balance cohort differences.
The originator-adalimumab (n=73) and SB5-adalimumab (n=56) cohorts were 39.7% and 60.7% men (P =.018); had a mean age of 38.6±11.6 and 41.8±12.1 years; they had received treatment for 3.5±2.7 and 4.1±3.1 years; and fecal calprotectin was 521.7±1034.8 and 209.7±298.0 mg/g (P =.020), respectively.
Among a subset of 54 patients from each group, baseline Harvey-Bradshaw index (HBI) scores were similar between the originator- and SB5-adalimumab recipients (mean, 3.2 vs 3.2). At week 26, HBI scores had decreased among the originator cohort and increased in the SB5 group (mean, 2.5 vs 3.5); at week 52, scores had increased in both groups (mean, 3.2 vs 4.0), respectively.
For C-reactive protein (CRP), the levels were 4.5 and 3.8 mg/L at baseline, 3.0 and 4.8 mg/L at week 26, and 2.9 and 2.8 mg/mL at week 52 among the originator- and SB5-adalimumab groups, respectively.
Fecal calprotectin levels were similar at baseline (mean, 203 vs 214 mg/g), differed at week 26 (mean, 140 vs 410 mg/g) and were similar again at week 52 (mean, 201 vs 224 mg/g).
Drug concentrations were not meaningfully different between the 2 groups.
During the study, drug persistence was significantly lower among the SB5-adalimumab group (P <.001).
Discontinuation due to adverse events occurred among 6% of the originator-adalimumab and 43% of the SB5-adalimumab recipients. Many patients who discontinued SB5-adalimumab therapy reported skin irritation or pain (37%).
Limitations of the study included small sample size, missing data values, and the inherent limitations of retrospective observational studies.
Overall, SB5-adalimumab had similar clinical effects as originator-adalimumab; however, the biosimilar was associated with poorer drug persistence due to adverse events.
“Focus on reassurance of quality, safety and effectiveness of biosimilars, along with proper training in use of different devices, would be expected to reduce nocebo leading to discontinuation of effective therapies,” the study authors wrote. “This would lead to full realization of the potential cost and access advantages to health care services of using biosimilars for treating patients with IBD.”
Disclosure: One study author declared affiliations with biotech, pharmaceutical, and/or device companies. Please see the original reference for a full list of authors’ disclosures.
Lukas M, Kolar M, Reissigova J, et al. A switch from originator-adalimumab to the biosimilar SB5 in patients with Crohn’s disease: an analysis of two propensity score-matched cohorts. Scand J Gastroenterol. Published online March 2, 2022. doi:10.1080/00365521.2022.2041082