A randomised, crossover trial exploring the patient perspective and effectiveness of biosimilar adalimumab transition: IBD reference and biosimilar adalimumab cross over study (iBaSS)

Int J Clin Pharm. 2024 May 11. doi: 10.1007/s11096-024-01739-5. Online ahead of print.

Abstract

Background: Patient satisfaction has been positively associated with adherence which is expected to impact outcomes. Although vital for successful implementation of biosimilar medicines, little is known about the patient perspective of transition.

Aim: The aim of this study was to investigate clinical outcomes and patient experience of transitioning between reference adalimumab and a biosimilar (SB5).

Method: iBaSS is a phase IV single-centre, prospective, randomised, single-blind, cross-over study in adult subjects with Crohn's disease. Participants, stable on adalimumab before consent, received 24 weeks of treatment with both reference adalimumab and SB5. The primary outcome was the proportion of patients maintaining baseline clinical status throughout each treatment period, with patients' perspective of disease control and treatment satisfaction assessed as secondary outcomes.

Results: A total of 112 participants, representative of the heterogeneous patient populations encountered in routine clinical practice, were enrolled. A similar proportion of participants maintained baseline clinical status through each treatment period: 81.8% with reference adalimumab and 79.5% with SB5. Patient reported outcomes (IBD-Control questionnaire (SB5: 15.5; reference adalimumab 15) and TSQM), adverse events and therapeutic drug monitoring remained consistent through both treatment periods, although a higher median injection pain VAS score was noted with SB5 (53/100 versus 6/100 with reference adalimumab). The number of switches undertaken in the study did not impact serum drug concentration or immunogenicity.

Conclusion: This study, mimicking real world adalimumab transition, demonstrates that patients undertaking brand transition can be expected to have consistent clinical and satisfaction outcomes.

Clinical trial registered with eudract: Number 2018-004967-30.

Keywords: Adalimumab; Biosimilar pharmaceuticals; Crohn disease; Patient reported outcome measures; Patient satisfaction.