P85 Switching from adalimumab originator to biosimilar: a 3-year retrospective cohort analysis

Abstract

Abstract Biological drugs have revolutionized the treatment of immune-mediated inflammatory diseases. Clinical experience and evidence suggest that biosimilars can be used as safely and effectively as their originator. However, patients’ perceptions of biosimilars are that they are inferior to the originator. Currently, few studies have assessed the tolerability and efficacy of switching from the adalimumab originator to a biosimilar in patients with well-controlled moderate-to-severe psoriasis. Our objective was to describe the clinical experience of switching patients from the adalimumab originator to a biosimilar and that of switching back to the originator for those intolerant to biosimilars. A single-centre, retrospective cohort study was conducted to identify patients with moderate-to-severe psoriasis who had switched from the adalimumab originator (Humira®) to a biosimilar (Amgevita® or Imraldi®) from 2018 to 2022. Patient data were obtained from a combination of patient records and databases, including the British Association of Dermatologists Biologics and Immunomodulators Register (BADBIR) and the National High Tech Prescribing Hub. Patients were excluded from the study if their treatment duration on an adalimumab biosimilar was < 16 weeks or if they were being treated for an indication other than psoriasis. From 2018 to 2022, 100 patients who switched from the adalimumab originator to a biosimilar were identified. At week 16, 81 patients (81%) maintained their initial switch from the adalimumab originator to biosimilar. Nineteen (19%) patients who were switched to an adalimumab biosimilar were switched back to the originator secondary to adverse events. Maintenance or improvement in baseline Psoriasis Area and Severity Index (PASI) and Dermatology Life Quality Index (DLQI) was observed in 91% and 90%, respectively, in patients who remained on a biosimilar. For those intolerant to biosimilars, maintenance or improvement in baseline PASI and DLQI was still observed although in fewer patients: 63% and 47%, respectively. Our study demonstrates that drug efficacy was recaptured and adverse events were ameliorated for all patients switched from an adalimumab biosimilar back to the originator. For patients who did not tolerate biosimilar switch, reasons for switching back to the originator mirrored those reported in the literature. All patients who switched back to the originator from a biosimilar recovered from loss of efficiency and the adverse events they had reported. Physicians should be confident in switching patients with well-controlled psoriasis to adalimumab biosimilars. For the small proportion of patients who experienced loss of efficacy or adverse events, all were recaptured by either switching to an alternative adalimumab biosimilar or switching back to the adalimumab originator.