Outcomes Following Adalimumab Bio-originator to Biosimilar Switch-A Comparison Using Real-world Patient- and Physician-Reported Data in European Countries

Abstract

Introduction: The aim of this work is to compare real-world outcomes of patients with rheumatoid arthritis (RA) receiving adalimumab (ADA) bio-originator (non-switchers) to those who had switched from ADA bio-originator to an ADA biosimilar (switchers) on the basis of the hypothesis that these outcomes would differ.

Methods: Data were drawn from the Adelphi RA Disease Specific Programme™, a point-in-time survey of physicians and their patients in Europe (France, Germany, Italy, Spain, UK) in 2020. Physicians completed a questionnaire for their next ten adult patients with RA, followed by four additional patients who had switched from ADA bio-originator to an ADA biosimilar (switchers). Physician- and patient-reported outcomes (PROs) for switchers and non-switchers were compared by propensity score matching.

Results: Three hundred and three rheumatologists provided data for 160 non-switchers and 225 switchers, 140 patients provided data; 51 non-switchers, 89 switchers. According to physician-reported disease activity, non-switchers were more likely to improve on their current ADA treatment than switchers (68%, n = 108 vs. 26%, n = 59 p < 0.001) and less likely to worsen (1%, n = 2 vs. 9%, n = 20; p < 0.01). Physician-reported patient adherence was significantly lower amongst switchers versus non-switchers (0.66 vs. 0.78, respectively; p = 0.04). More non-switchers than switchers were reported by their physicians to be consistent in taking their RA medicine (p < 0.001). Compared with non-switchers, PRO measures indicated quality of life was worse (EQ-5D Visual Analogue Scale: 62.9 vs. 71.9; p < 0.001) and activity impairment was greater (Work Productivity Activity Index: 31.0 vs. 24.4; p = 0.02) for switchers, with trends for poorer health status and greater pain.

Conclusions: Non-medical switching in RA treatment may lead to unforeseen outcomes that should be considered by health decision-makers.

Keywords: Adalimumab; Biosimilar; Disease burden; Non-medical switching; Rheumatoid arthritis.

Fig. 1

Physician-reported results of patients with RA who were receiving adalimumab: Non-switcher versus switcher patients. Scale: 0.0–1.0 (binary scale). RA rheumatoid arthritis. Non-switcher patients prescribed adalimumab bio-originator who were not switched to an adalimumab biosimilar, NMS, patients previously prescribed adalimumab bio-originator who had been switched to an adalimumab biosimilar. Physician-reported results from the patient-record form. Non-switcher and NMS patients were compared using propensity score matching. *Significance at p < 0 05. Red text denotes negative result

Fig. 2

Physician-reported results of % disease severity change in patients with RA who were receiving adalimumab: Non-switcher versus switcher patients. RA rheumatoid arthritis. Non-switcher patients prescribed adalimumab bio-originator who were not switched to an adalimumab biosimilar. NMS patients previously prescribed adalimumab bio-originator who had been switched to an adalimumab biosimilar. % disease severity change from initiation of current therapy to time of data collection. Physician-reported results from the patient-record form. Non-switcher and NMS patients were compared using propensity score matching. *Significance at p < 0.05

Fig. 3

Physician-reported results of disease severity change in patients with RA who were receiving adalimumab: Non-switchers versus switchers. RA rheumatoid arthritis. Non-switcher patients prescribed adalimumab bio-originator who were not switched to an adalimumab biosimilar. NMS patients previously prescribed adalimumab bio-originator who had been switched to an adalimumab biosimilar. Binary severity change from initiation of current therapy to time of data collection. Severity rated as mild, moderate, or severe. Physician-reported results from the patient-record form. Non-switcher and NMS patients were compared using propensity score matching. *Significance at p < 0 05. Red text denotes negative result

Fig. 4

Self-reported treatment satisfaction and adherence reported by patients with RA receiving adalimumab: Non-switcher versus switcher patients. RA rheumatoid arthritis. Non-switcher patients prescribed adalimumab bio-originator who were not switched to an adalimumab biosimilar. NMS patients previously prescribed adalimumab bio-originator who had been switched to an adalimumab biosimilar. Patient-reported results from the patient self-completion form. Non-switcher and NMS patients were compared using propensity score matching. *Significance at p < 0 05. Red text denotes negative result

Fig. 5

Self-reported treatment outcomes reported by patients with RA receiving adalimumab: Non-switcher versus switcher patients. EQ5D EuroQol-5 dimension, FACIT Fatigue, functional assessment of chronic illness therapy – fatigue, HAQ health assessment questionnaire, RA rheumatoid arthritis, VAS visual analogue scale, WPAI work productivity and activity impairment. Non-switcher patients prescribed adalimumab bio-originator who were not switched to an adalimumab biosimilar. NMS patients previously prescribed adalimumab bio-originator who had been switched to an adalimumab biosimilar. Patient-reported results from the patient self-completion form. Non-switcher and NMS patients were compared using propensity score matching. EQ5D calculated using the German tariff. *Significance at p < 0 05. Red text denotes negative result