Comparative effectiveness of two adalimumab biosimilars in 1318 real-world patients with inflammatory rheumatic disease mandated to switch from originator adalimumab: nationwide observational study emulating a randomised clinical trial.

OBJECTIVES: In 2018, a nationwide mandatory switch from originator to biosimilar adalimumab was conducted in Denmark. The available biosimilar was GP2017 (Hyrimoz) in Eastern regions and SB5 (Imraldi) in Western regions. We aimed to assess the comparative effectiveness of GP2017 versus SB5 in patients with rheumatoid arthritis (RA)/psoriatic arthritis (PsA)/axial spondyloarthritis (AxSpA). METHODS: Observational cohort study based on the DANBIO registry with geographical cluster pseudo-randomisation, analysed by emulating a randomised clinical trial. Main outcome was adjusted 1-year treatment retention (Cox regression). Furthermore, 6 months' remission rates (logistic regression), reasons for withdrawal and back-switching to originator were investigated (overall and stratified by indication). RESULTS: Overall, of 1570 eligible patients, 1318 switched and were included (467 RA/321 PsA/530 AxSpA); 623 (47%) switched to GP2017, 695 (53%) to SB5. Baseline characteristics of the two clusters were largely similar, but some differences in registration practice were observed. The combined 1-year retention rate for the two biosimilars was 89.5%. Compared with SB5, estimated risk of withdrawal for GP2017 was lower (HR 0.60; 95% CI 0.42 to 0.86) and 6 months' remission rate was higher (OR 1.72; 95% CI 1.25 to 2.37). Stratified analyses gave similar results (statistically significant for RA). During 1 year, 8.5% and 12.9% withdrew GP2017 and SB5, respectively (primarily lack of effect and adverse events), of whom 48 patients (3.6%) back-switched. CONCLUSION: This head-to-head comparison of GP2017 versus SB5 following a mandatory switch from the originator indicated differences in effectiveness in routine care. This may reflect a true difference, but other explanations, for example, differences in excipients, differences between clusters and residual confounding cannot be ruled out.

Counting the costs: a nationwide study on healthcare use following an adalimumab biosimilar switch in >1300 inflammatory arthritis patients.

Background: In Denmark, cost savings motivate mandatory biosimilar switches. In 2018, patients switched from originator to biosimilar adalimumab, that is, to GP2017 in Eastern and to SB5 in Western Denmark. However, concerns were raised about additional costs covering, that is, an increased number of outpatient visits due to patient education, treatment monitoring, and patient concerns. Objectives: To investigate whether the switch led to increased total healthcare costs, defined as costs related to in- and outpatient contacts in hospitals and the primary sector and use of prescription medicine (excluding biological treatment). Design: Observational cohort study with geographical cluster pseudo-randomization. Methods: Patients with rheumatoid arthritis, psoriatic arthritis (PsA), and axial spondyloarthritis (AxSpA), who switched were identified in the nationwide DANBIO registry. Total healthcare costs 9 months before and after the switch were captured from the National Patient and Prescription registries. The difference between pre- and post-switch costs was estimated by a generalized estimation equations (GEE) model. Results: Overall, 1316 patients switched to GP2017 (n = 621) or SB5 (n = 695). Total healthcare costs were mainly driven by hospital costs. The monthly fluctuations of hospital costs 9 months before and after the switch were largely similar or decreased. In the adjusted analyses (GEE), hospital costs decreased after the switch (by approximately 15%) for GP2017 switchers, especially PsA (estimate = 0.83; 95% CI 0.75-0.92) and AxSpA patients (estimate = 0.85; 0.77-0.93), with no significant changes for SB5 switchers. Conclusion: We found no increase in total healthcare costs in 9 months following a nationwide mandatory adalimumab originator to biosimilar switch. Our findings were strengthened by similar results for GP2017 and SB5.

Infliximab biosimilar-to-biosimilar switching in patients with inflammatory rheumatic disease: clinical outcomes in real-world patients from the DANBIO registry.

OBJECTIVE: Successful uptake of biosimilars in rheumatology is limited by lack of real-world evidence regarding effectiveness of biosimilar-to-biosimilar switching. We investigated infliximab biosimilars CT-P13-to-GP1111 switching among patients with rheumatoid arthritis (RA), psoriatic arthritis (PsA) and axial spondyloarthritis (AxSpA). METHODS: Observational cohort study from the DANBIO registry. Patients were classified as originator-naïve or originator-experienced. Retention rates of 1-year GP1111 treatment were explored (Kaplan-Meier). We identified baseline factors (at the time of switch) associated with withdrawal of GP1111 (multivariable Cox-regression analyses with HRs including originator treatment history). Changes in subjective and objective measures of disease activity 4 months before and after the switch were assessed in individual patients. RESULTS: Of 1605 patients (685 RA, 314 PsA and 606 AxSpA, median disease duration was 9 years, 37% in Clinical Disease Activity Index/Ankylosing Spondylitis Disease Activity Score remission), 1171 were originator-naïve. Retention rates at 1-year were 83% (95% CI: 81% to 85%) and 92% (95% CI: 90% to 95%) for the originator-naïve and originator-experienced, respectively. GP1111 retention rates were higher in originator-experienced compared to originator-naïve with RA (HR=0.4 (95% CI: 0.2 to 0.7)) and PsA (HR=0.2 (95% CI: 0.1 to 0.8)), but not significantly for AxSpA: HR=0.6 (95% CI: 0.3 to 1.2). Lower disease activity was associated with higher retention. Changes in disease activity preswitch and postswitch were close to zero. CONCLUSION: This real-world observational study of more than 1600 patients with inflammatory arthritis showed high 1-year retention following a nationwide infliximab biosimilar-to-biosimilar switch. Retention was higher in originator-experienced and in patients with low disease activity, suggesting outcomes to be affected by patient-related rather than drug-related factors.

Initiation of and persistence with P2Y12 inhibitors in patients with myocardial infarction according to revascularization strategy: a nationwide study.

BACKGROUND: We aimed to analyse initiation of and persistence with P2Y12 inhibitors after first-time myocardial infarction (MI). METHODS AND RESULTS: Using Danish nationwide registries, we identified patients ≥30 years with first-time MI during 1 January 2005-30 June 2016 and subsequent prescriptions of P2Y12 inhibitors. Independent factors related to initiation of and persistence with P2Y12 inhibitors were analysed by multivariable logistic regression and a Cox proportional hazards model. Patients were stratified by revascularization strategy: percutaneous coronary intervention (PCI), coronary artery bypass graft (CABG), or medical therapy alone (MTA). Overall, 79 597 MI patients were included with 39 172 undergoing PCI, 2619 CABG, and 16 640 MTA, showing initiation of P2Y12 inhibitors of 93.4%, 49.0%, and 51.5%, respectively. Congestive heart failure, cerebrovascular disease, cardiac dysrhythmias, renal failure, previous bleeding, and oral anticoagulants were associated with less initiation of P2Y12 inhibitors. Female sex was associated with less initiation of P2Y12 inhibitors following MTA. MTA, coronary angiography, cerebrovascular disease, diabetes with complications, previous bleeding, antidiabetics, and ticagrelor as P2Y12 inhibitor were associated with non-persistence, whereas female sex, advanced age, and concomitant pharmacotherapy with angiotensin-converting enzyme inhibitors, beta-blockers, statins, oral anticoagulants, and aspirin were associated with high persistence. CONCLUSION: Initiation of P2Y12 inhibitors in PCI-treated MI patients was high in contrast to those treated with CABG or MTA and patients with certain comorbidities. Further studies on the benefit-risk ratio of P2Y12 inhibitors in CABG-treated or MTA-treated patients and patients with comorbidities after first-time MI are warranted, as is focus on persistence among patients receiving MTA, patients with comorbidities, and users of ticagrelor.

Antithrombotic treatment and major adverse cardiac events after bleeding in patients with myocardial infarction: a retrospective analysis of nationwide registry data.

AIMS: The aim of this study was to describe the use of antithrombotic therapy following a bleeding event among patients with myocardial infarction (MI), and the associated risk of major adverse cardiac events (MACE). METHODS AND RESULTS: Using Danish nationwide registries, patients hospitalized with a bleeding event within 1 year after MI were identified. Antithrombotic treatment with aspirin, clopidogrel, and/or vitamin K antagonists (VKA) was determined at the bleeding and at Day 90 and 180 post-bleed. Based on guidelines, patients were stratified into four groups: expected, reduced, discontinued, or intensified treatment. Risk of MACE (ischaemic stroke, MI, or death) within the first year was assessed by Cox proportional hazard models. A total of 3324 patients with a bleeding after MI were included. At Day 90 post-bleed, 1052 (31.7%) received expected antithrombotic treatment, 1301 (39.2%) reduced, 164 (4.9%) intensified, and 807 (24.3%) no treatment. Major adverse cardiac events occurred in 637 (19.2%) patients. With dual antiplatelet therapy as reference, adjusted hazard ratios for MACE were: aspirin 1.81 (1.06-3.09), clopidogrel 1.08 (0.64-1.82), VKA 1.08 (0.47-2.48), VKA + aspirin 1.97 (0.95-4.07), VKA + clopidogrel 0.26 (0.03-1.91), triple 1.73 (0.50-5.95), and no treatment 1.93 (1.11-3.36). CONCLUSION: The majority of MI patients reduced or discontinued their antithrombotic therapy post-bleed. Patients in monotherapy with aspirin or no treatment post-bleed had a higher risk of MACE Further studies of optimal antithrombotic treatments after a bleed are needed.