Rheumatology (Oxford). 2021 Dec 17:keab933. doi: 10.1093/rheumatology/keab933. Online ahead of print.
ABSTRACT
OBJECTIVES: To compare treatment retention between biosimilars and their originator products among first starters (etanercept, infliximab, adalimumab and rituximab), as well as after non-medical switch.
METHODS: Patients with rheumatic diseases starting, for the first time, an originator or biosimilar etanercept, infliximab, adalimumab, and rituximab were identified in the national Swedish Rheumatology Quality register. Moreover, patients switching from an originator to its biosimilar were identified, and individually matched to patients continuing on the originator. One-year treatment retention was calculated, and hazard ratios (HR) for discontinuation with 95% confidence intervals (CI) were estimated, adjusting for comorbidities and socioeconomic factors.
RESULTS: In total, 21443 first treatment courses were identified. The proportion of patients still on drug at one year, and the HR for discontinuation, revealed no differences across adalimumab (Humira, Imraldi, Amgevita and Hyrimoz) nor across rituximab products (Mabthera, Ritemvia/Truxima and Rixathon). The proportions on drug at one year were similar for Benepali (77%) and Enbrel (75%) and the adjusted HR for Benepali compared to Enbrel was 0.91 (95% CI: 0.83-0.99). For infliximab, the proportion still on drug at one year was 67% for Remicade and 66% for Remsima/Inflectra, and the HR in comparison with Remicade was: 1.16 (95% CI: 1.02-1.33).Among 2925 patients switching from an originator drug to one of its biosimilars, we noted no statistically significant or clinically relevant differences in drug survival compared those who remained on originator therapy.
CONCLUSION: This large observational study supports the equivalence of bDMARD biosimilar products and originators when used in routine rheumatology care.
PMID:34919663 | DOI:10.1093/rheumatology/keab933
