Switch from original to biosimilar adalimumab SB-5 in patients with Crohn's disease - long-term results
Abstract
Background and aims: Originator-adalimumab, an established treatment for patients with Crohn's disease (CD) showed no difference in efficacy or adverse events vs the adalimumab biosimilar SB5 (SB5-adalimumab) over 10 weeks of treatment. To understand the long-term efficacy of SB5-adalimumab in CD, patients who switched from originator-adalimumab to SB5-adalimumab were compared to a cohort who remained on originator-adalimumab over a follow up of 104 weeks.
Methods: In this analysis, data on patients >=18 years and diagnosed with CD treated at the IBD ISCARE centre were collected prospectively between July 2018 and January 2021. Clinical disease activity as measured by Harvey-Bradshaw index (HBI) at Week 52 was the primary outcome, while C-reactive protein (CRP), faecal calprotectin (FC), adalimumab trough levels in Weeks 10, 26, 52, 78, and 104, adverse events leading to therapy withdrawal, and persistence on treatment were secondary outcomes.
To ensure comparable treatment cohorts, patients were propensity score matched (PSM) for age, gender, diagnosis, and disease activity. Results: A total of 54 patients were matched according to the given criteria in each group.
At Week 52, the mean [SD] HBI score was 3.2 (2.5) in the originator-adalimumab group and 4.0 (3.6) in SB5-adalimumab patients (difference [95% CI] -0.78 [-2.8, 1.3]). Similarly, no clinically significant differences in CRP, FC, or trough levels were noted between originator-adalimumab and SB5-adalimumab cohorts through Week 52.
The Kaplan-Meier estimates (95% CI) of patients remaining on treatment for the originator-adalimumab vs SB5-adalimumab cohorts were 0.870 (0.785-0.965) vs 0.648 (0.533-0.789) at Week 52. Conclusions: These long-term study results in CD patients after a non-medical switch from originator-adalimumab to SB5-adalimumab showed that the biosimilar SB5 had similar therapeutic effects as originator-adalimumab in terms of clinical disease activity, biological parameters, and pharmacokinetics profile at the primary endpoint of 52 weeks, as well as 104 weeks.
Differences in persistence were not clinically driven. Persistence on treatment was lower in patients treated with biosimilar adalimumab SB-5.