Background: Switches to biosimilars (BioS) are not always well-accepted by patients. Patients’ beliefs, concerns, and knowledge about health could impact their satisfaction towards switching.

Objectives: To analyse patient beliefs about medicine and health knowledge that may impact patients’ satisfaction after a switch to a BioS of adalimumab.

Methods: YU-MATTER (NCT05427942), a prospective multicentric observational French study included patients with inflammatory bowel disease (IBD) or chronic inflammatory rheumatic disease (CIRD), treated with adalimumab (either the reference product or a BioS with low concentration, 50 mg/mL). Patients were switched to CT-P17: adalimumab BioS with high concentration and citrate-free and followed-up for 3 months. The main outcome was patient satisfaction with CT-P17 after 3 months (M3), collected through a 7-point Likert scale and analysed as satisfied. Patient beliefs about medicine were assessed before the switch, using the BMQ questionnaire including perceived necessity and concerns subscores ^[1] , and knowledge was assessed through a health literacy questionnaire (HLS-EU-Q16 ^[2] ). Association between satisfaction and beliefs/knowledge was explored through Wilcoxon test.

Results: Of 232 patients, 65 (28%) had a CIRD [radiographic axial spondyloarthritis, axSpA (n=35), rheumatoid arthritis (n=17), or non-radiographic axSpA/psoriatic arthritis (n=13)], and 167 (82%) IBD [Crohn’s disease (n=136), ulcerative colitis (n=31)]. Median disease duration was 9 years [interquartile range, IQR: 5;16], median age was 43 years [IQR 31;56], 49.6% of patients were women, and median total adalimumab duration before the switch was 47 months [IQR 24;82]. Before the switch, patients had an overall positive view of the drug (BMQ-necessity score was higher than BMQ-concerns, median differential: +5, IQR: 2;8). Health literacy (HLS-EU-Q16) was adequate in 48.7% of patients; problematic in 36.2%, and insufficient in 15.1%. Both scores (BMQ and HLS-EU-Q16) were similar according to patient characteristics (age, sex, type of disease, disease duration, and duration of adalimumab before the switch). The correlation between the HLS-EU-Q16 score and the BMQ necessity-concerns differential was moderate (Spearman coefficient: 0.37, 95%CI: [0.26-0.48]). At 3 months, 144/189 evaluable patients (76.2%) were satisfied with CT-P17. The median necessity-concerns differential was higher in patients satisfied with CT-P17 compared to other patients (+6 vs. +3, p=0.001); the HLS-EU-Q16 score was not associated with patient satisfaction (p=0.12).

Conclusion: This real-world study showed that patients switching to CT-P17 were generally convinced of the treatment necessity; the differential between necessity and concerns about the treatment was associated to a higher satisfaction with CT-P17. The level of health literacy was problematic or insufficient in around half of these patients with long-standing disease and long-standing biologic use. These results suggest that although satisfaction with switching was generally high, beliefs and concerns remain important and could lead to non-adherence. Patient information and education should be reinforced before a switch to a BioS.

REFERENCES: [1] Horne R, et al. The Beliefs about Medicines Questionnaire: The Development and Evaluation of a New Method for Assessing the Cognitive Representation of Medication. Psychology & Health 1999.

[2] Rouquette A et al. Validity and measurement invariance across sex, age, and education level of the French short versions of the European Health Literacy Survey Questionnaire. PLoS ONE 2018.

Acknowledgements: This study was funded and sponsored by Celltrion Healthcare France. We thank all patients for their active participation in the study by answering questionnaires, patient associations (AFA, ANDAR, AFS) for their contribution to the study design and e-Health Services Sanoïa for the follow-up during the study and their input to results interpretation.

Disclosure of Interests: Laure Gossec AbbVie, Amgen, BMS, Celltrion Healthcare, Galapagos, Gilead, GSK, Janssen, Lilly, MSD, Novartis, Pfizer, Sandoz, UCB, AbbVie, Amgen, BMS, Celltrion Healthcare, Galapagos, Gilead, GSK, Janssen, Lilly, MSD, Novartis, Pfizer, Sandoz, UCB, Lilly, Pfizer, Sandoz, UCB

, Guillaume BOUGUEN AbbVie, Takeda, MSD, Janssen, Celltrion

, AbbVie, Takeda, Mylan, Pfizer, Sandoz, Amgen, Ferring, Janssen, Celltrion

, AbbVie, Takeda, Fresenius, Janssen, Vifor, Sandoz

, Hubert Marotte AbbVie, Amgen, Bristol Myers Squibb, Celltrion HealthCare, Galapagos, Lilly France, Merck Sharp & Dohme, Novartis, Nordic Pharma, Pfizer, and Sanofi Aventis

, Bristol Myers Squibb, Celltrion HealthCare, Galapagos, Lilly France, Novartis, Nordic Pharma, Pfizer, and Sanofi Aventis

, Lucile Foulley Celltrion Healthcare France, Caroline HABAUZIT Celltrion Healthcare France, Salim Benkhalifa Celltrion Healthcare France, Vered Abitbol Pfizer, Takeda, Amgen, Mylan Viatris, Sandoz, Janssen, Fresenius, Gilead, Tillotts, Celltrion

, Pfizer, Takeda, Amgen, Mylan Viatris, Sandoz, Janssen, Fresenius, Gilead, Tillotts, Celltrion.