Comparison of injection-site reactions between the etanercept biosimilar SB4 and the reference etanercept in patients with rheumatoid arthritis from a phase III study

Leveraging the holistic benefits of biosimilars in Europe - part 2: how payers can safeguard the future of a healthy biosimilar market environment

INTRODUCTION

Biosimilars have improved access to biologic medicines; however, historical thinking may jeopardize the viability of future markets.

AREAS COVERED

An expert panel of eight diverse European stakeholders provided insights about rethinking biosimilars and cost-savings, reducing patient access inequalities, increasing inter-market equity, and improving education. The insights reported here (Part 2) follow a study that provides perspectives on leveraging the holistic benefits of biosimilars for market sustainability based on independent survey results and telephone interviews of stakeholders from diverse biosimilar markets (Part 1). Directional recommendations are provided for payers.

EXPERT OPINION

The panel's market maturity framework for biosimilars has three stages: 'Invest,' 'Expand' and 'Harvest.' Across market stages, re-thinking the benefits of biosimilars beyond cost-savings, considering earlier or expanded access/new indications, product innovations, and re-investment of biosimilar-generated cost-savings should be communicated to stakeholders to promote further engagement. During 'Expand' and 'Harvest' stages, development of efficient, forward-looking procurement systems and mechanisms that drive uptake and stabilize competition between manufacturers are key. Future biosimilars will target various therapy areas beyond those targeted by existing biosimilars. To ensure a healthy, accessible future market, stakeholders must align their objectives, communicate, collaborate, and coordinate via education, incentivization, and procurement, to maximize the totality of benefits.

Etanercept originator versus etanercept biosimilar for the treatment of rheumatoid arthritis as a first biologic: results from the BSRBR-RA

OBJECTIVES

Etanercept biosimilars show comparable efficacy to their originators among biologic-naïve patients with RA in randomized controlled trials. Nationwide guidelines have obligated prescribing of etanercept biosimilars from 2016, resulting in significant cost savings. This analysis aimed to compare the effectiveness of etanercept originator vs etanercept biosimilar amongst biologic-naïve RA patients treated in routine clinical practice in the UK.

METHODS

Biologic-naïve RA patients starting etanercept in the British Society for Rheumatology Biologics Register in Rhematoid Arthritis (BSRBR-RA) cohort study from 2010 were included. Data collected at start of therapy includes patient demographics and disease activity. Follow-up data includes changes in disease activity and anti-rheumatic therapy. Six- and 12-month primary outcomes include DAS for 28-joints (DAS28) remission, EULAR response and minimal clinically important difference in function. Etanercept drug survival was assessed using Kaplan-Meier and Cox regression, including reasons for treatment withdrawal. Multiple imputation accounted for missing data. Propensity-decile adjustment was used to account for confounding by indication.

RESULTS

A total of 1806 biologic-naïve RA patients started etanercept: 1009 originator, 797 biosimilar. At 6 and 12 months, the proportion of patients achieving DAS28 remission and EULAR response were similar between treatments. During follow-up, 19% of originator patients switched onto etanercept biosimilar. Patients were censored at time of switch. Patients on originator were no more likely to stop therapy vs biosimilar; 71% of originator and 76% of biosimilar patients remained on therapy at 1 year.

CONCLUSIONS

In one of the largest analyses of patients with RA, biologic-naïve RA patients treated with etanercept originator showed similar outcomes vs biosimilar using real-world data. Drug survival, and disease activity after 6 and 12 months of therapy, was similar between cohorts.

Biosimilars in the treatment of rheumatoid arthritis: a pharmacokinetic overview

INTRODUCTION

As of May 2023, 19 and 18 biosimilars have been approved for the treatment of rheumatoid arthritis (RA) by the European Medicines Agency (EMA) and United States Food and Drug Administration (US FDA) respectively.

AREA COVERED

Pharmacokinetic results of phase 1 studies of approved biosimilars were reviewed by systematic literature search. The impact of immunogenicity on the pharmacokinetic data and clinical response was assessed, and the potential benefit of monitoring serum concentrations of biologic drugs is discussed. The advantage of subcutaneous CT-P13 (an infliximab biosimilar) in clinical practice is reviewed.

EXPERT OPINION

Biosimilars are approved based on the totality of evidence including comparable physiochemical properties, PK / PD profiles, and clinical efficacy and safety to the originator. To utilize biosimilars more effectively, physicians should be aware of the utility of combination DMARD therapy to reduce immunogenicity and maintain efficacy and PK profile. PK monitoring, however, is not currently recommended in clinical practice. CT-P13 subcutaneous (SC) is the first SC infliximab used for treatment of RA patients. Based on data from clinical studies and the real world, SC-infliximab is an attractive therapeutic option compared to IV formulations of infliximab based on its efficacy, pharmacokinetics, patient-reported outcomes, and safety profile.

Safety and Effectiveness of Etanercept Biosimilar SB4 for Rheumatic Diseases in South Korea: Real-World Post-marketing Surveillance Data

INTRODUCTION

SB4 is the first approved biosimilar of etanercept, a biologic tumor necrosis factor inhibitor, to treat various autoimmune diseases including axial spondylarthritis (axSpA), rheumatoid arthritis (RA), psoriatic arthritis (PsA), and plaque psoriasis (PsO). This post-marketing surveillance (PMS) study of SB4 investigated safety and effectiveness in routine clinical practice and is part of the drug approval process in Korea.

METHODS

This prospective, multi-center, open-label, observational, phase IV PMS study was designed to enroll patients with axSpA, RA, PsA, and PsO in Korea from September 2015 to September 2019. Both etanercept-naïve patients or patients switched from reference etanercept were included. SB4 was administered weekly via subcutaneous injections using pre-filled syringes. Safety was assessed by the incidence of adverse events (AEs), adverse drug reactions (ADRs) and serious adverse events (SAE). Effectiveness was assessed by the change from baseline of investigator-rated Bath Ankylosing Spondylitis Disease Activity Index (BASDAI) in patients with ankylosing spondylitis (AS) and disease activity score-28 (DAS28) in patients with RA.

RESULTS

Among 316 enrolled patients, 314 were included in the safety analysis (176 with AS and 138 with RA). The overall incidence of AEs, ADRs and serious AEs were 17.8, 9.9, and 1.3%, respectively. Most AEs were mild (66.7%) or moderate (31.1%) and not related to SB4 (58.9%). Most common AEs were injection site pruritus (1.9%) and injection site rash (1.3%). At week 24, mean disease activity scores significantly decreased compared to baseline in naïve patients with AS and RA (BASDAI 2.7 vs. 6.2, p < 0.0001; DAS28 3.8 vs. 5.7, p < 0.0001) and in switched patients with AS and RA (BASDAI 1.0 vs. 1.3, p = 0.0018; DAS28 2.4 vs. 2.9, p = 0.0893).

CONCLUSION

This first real-world evidence of SB4 from a phase IV PMS study in Korea shows comparable effectiveness to historical SB4 real-world evidence without any new significant safety signals.

An etanercept O-glycovariant with enhanced potency

Most therapeutic proteins are glycosylated with N-glycans and/or O-glycans. N-glycans on therapeutic proteins have been extensively studied for their control strategy and impact on drug product quality. However, knowledge of O-glycosylation in therapeutic protein production and its impact on product quality remains elusive. To address this gap, we generated an O-glycoengineered Chinese Hamster Ovary (CHO) cell line platform to modulate O-glycosylation of therapeutic proteins and investigated the impact of O-glycans on the physicochemical and biological properties of etanercept. Our results demonstrate that this CHO cell line platform produces controlled O-glycosylation profiles containing either truncated O-glycans (sialylTn and/or Tn), or sialylCore 3 alone, or sialylCore 1 with sialylTn or sialylCore 3 O-glycans on endogenous and recombinant proteins. Moreover, the platform demonstrated exclusive modulation of O-glycosylation without affecting N-glycosylation. Importantly, certain O-glycans on etanercept enhanced tumor necrosis factor-α binding affinity and consequent potency. This is the first report that describes the systematic establishment of an O-glycoengineered CHO cell line platform with direct evidence that supports the applicability of the platform in the production of engineered proteins with desired O-glycans. This platform is valuable for identifying O-glycosylation as a critical quality attribute of biotherapeutics using the quality by design principle.

Efficacy and Drug Survival after Switching from Etanercept to the Biosimilar SB4: A Real-Life Long-Term Study

We evaluated the 3-year drug survival and efficacy of the biosimilar SB4/Benepali in rheumatoid arthritis (RA), psoriatic arthritis (PsA) and ankylosing spondylitis (AS) patients, previously treated with etanercept (ETA). Drug survival rate was calculated using the Kaplan–Meier method and Cox proportional hazard models were developed to examine predictors of SB4 discontinuation. 236 patients (120 RA, 80 PsA and 36 AS), aged 60.7 ± 13.8 years and with an ETA duration of 4.1 ± 3.4 years were included. The 3-year retention rate for SB4 was 94.4%, 88% and 86% in AS, RA and PsA patients, respectively, with no difference between groups. Patients without comorbid disease had higher retention rates vs. patients with comorbid disease (90% vs. 60%, p < 0.0001). Disease activity, as measured by DAS28, DAPSA and BASDAI remained stable over the 3 years. Comorbid disease (hazard ratio; HR: 4.06, p < 0.0001) and HAQ at baseline (HR: 2.42, p = 0.0024) significantly increased the risk of SB4 discontinuation, while previous ETA duration was negatively associated with SB4 discontinuation (HR: 0.97, p = 0.0064). Forty-one (17.4%) patients left the study due to the interruption of the SB4 treatment, 31 (75.6%) discontinued due to inefficacy and 10 (24.4%) due to adverse events. This real-life study confirms the similar efficacy profile of ETA with long-term retention and a good safety profile in inflammatory arthritis patients.

Effectiveness, safety and economic analysis of Benepali in clinical practice

OBJECTIVE

To assess the effectiveness, safety and cost of Etanercept biosimilar in patients with rheumatoid arthritis (RA), spondyloarthritis (SpA) and psoriatic arthritis (PsA) compared to the standard drug in real clinical practice.

PATIENTS AND METHODS

Retrospective observational study. Case series of 138 patients with RA, SpA or PsA treated with at least one dose of Benepali® (n = 79) or Enbrel® (n = 59). Drug retention time was the primary efficacy endpoint compared to the biosimilar and the original. The proportion of patients achieving low disease activity or remission after 52 weeks was used as the secondary outcome. Safety was assessed by means of the adverse effects incidence rate. A cost minimization analysis was performed.

RESULTS

No differences were observed regarding treatment retention time between drugs (median [95% confidence interval, 95% CI] at 12.0 months [10.2-12.0] for the biosimilar and 12.0 months [12.0-12.0] for the original). Similar improvements, in terms of inflammatory activity and physical function, were obtained after 52 weeks except for patients with SpA and PsA who, in general, experienced improvements of BASDAI and ASDAS with the original compared with the biosimilar. No significant differences were observed in the total number of adverse effects (.43 events/patient-years versus the biosimilar and .53 versus the original). Using the biosimilar in place of the original drug resulted in a net savings of 118,383.55 € (1,747.20 €/patient-years) for the hospital.

CONCLUSION

The biosimilar Benepali is as effective and safe as the original and much more cost-effective.

Batch-to-Batch Consistency of SB4 and SB2, Etanercept and Infliximab Biosimilars

Background

Biosimilars must meet stringent regulatory requirements, both at the time of authorization and during their lifecycle. Yet it has been suggested that divergence in quality attributes over time may lead to clinically meaningful differences between two versions of a biologic. Therefore, this study investigated the batch-to-batch consistency across a range of parameters for released batches of the etanercept biosimilar (SB4) and infliximab biosimilar (SB2).

Methods

SB4 (Benepali^®) and SB2 (Flixabi^®) were both developed by Samsung Bioepis and are manufactured in Europe by Biogen at their facility in Hillerød, Denmark. A total of 120 batches of SB4 and 25 batches of SB2 were assessed for consistency and compliance with specified release parameters, including purity, post-translational glycosylation (SB4 only), protein concentration, and biological activity.

Results

The protein concentration, purity, tumor necrosis factor-α (TNF-α) binding, and TNF-α neutralization of all batches of SB4 and SB2 were within the strict specification limits set by regulatory agencies, as was the total sialic acid (TSA) content of all batches of SB4.

Conclusions

Quality attributes of SB4 and SB2 batches showed little variation and were consistently within the rigorous specifications defined by regulatory agencies.

Electronic supplementary material

The online version of this article (10.1007/s40259-019-00402-0) contains supplementary material, which is available to authorized users.

Understanding and Minimising Injection-Site Pain Following Subcutaneous Administration of Biologics: A Narrative Review

Injection-site pain (ISP) is a subjective side effect that is commonly reported with the subcutaneous administration of biological agents, yet it may only be a concern to some. Multiple factors related to the product formulation, such as pH, volume and excipients, and/or to the injection process have the potential to contribute to ISP, while patient-related factors, such as low body weight, gender and age, can make an individual more susceptible to experiencing ISP. While total elimination of ISP remains unlikely with any subcutaneously administered agent, it can be minimised by helping the patient to develop a confident and competent injection technique via robust and effective training. Careful management of patient expectations along with open discussion regarding the potential risk of ISP may serve to minimise treatment-related anxieties and, importantly, allow the patient to remain in control of his/her treatment. Other interventions to help minimise ISP include psychological interventions, allowing biologics to reach room temperature prior to injection, using the most suitable injection device for the individual patient and selecting an alternative drug formulation, when available. Productive patient–physician communication remains important in order to support and optimise treatment experience and adherence, while also providing the opportunity for patients to discuss any ISP-related issues.

The switch from etanercept originator to SB4: data from a real-life experience on tolerability and persistence on treatment in joint inflammatory diseases

Aims:

Switching from originator to biosimilar is part of current practice in inflammatory rheumatic musculoskeletal diseases (iRMDs) such as rheumatoid arthritis (RA), psoriatic arthritis (PsA) and axial spondylarthritis (axSpA), with evidences derived from both etanercept (ETN) to SB4-switching randomized controlled trials and real-life registries. We investigated the safety and treatment persistence of ETN/SB4 in a multi-iRMD cohort derived from two rheumatology departments in our region.

Methods:

Adult patients with iRMDs, treated with ETN for at least 6 months and switched to SB4 in stable clinical condition, were eligible for this retrospective evaluation. Retrospective data on adverse events, loss of efficacy and persistence on treatment were collected until latest available follow-up.

Results:

A total of 220 patients (85 RA, 81 PsA, 33 axSpA, 14 juvenile idiopathic arthritis and seven other conditions; 142 females, mean age 58 ± 7 years, disease duration 12 ± 4 years, ETN duration 7 ± 4 years) were enrolled, with median follow-up of 12.1 (9.7–15.8) months. A total of 50 patients (22.7%) presented with at least one adverse event, with 36 (16.4%) disease flares and 30 (13.6%: 11 for safety and 19 loss of efficacy) SB4 withdrawals. Cumulative SB4 treatment persistence was 99.1%, 88.6% and 64.6% at 6, 12 and 18 months respectively. Back-switch to ETN was performed in 17/30 cases, the remaining cases were managed with change of biologic disease modifying or conventional synthetic anti-rheumatic drug. Age was the only significant predictor of SB4 interruption at 6 months.

Conclusion:

Our real-life data confirm the safety profile of switching from ETN to SB4, with slightly higher treatment persistence rates compared with other real-life registries.

Immunogenicity of Biosimilars for Rheumatic Diseases, Plaque Psoriasis, and Inflammatory Bowel Disease: A Review from Clinical Trials and Regulatory Documents

The goal of this narrative review was to summarize immunogenicity data of biosimilars or biosimilar candidates for rheumatic diseases, plaque psoriasis, or inflammatory bowel disease (IBD), available in peer-reviewed publications or regulatory documents. PubMed records and regulatory documents were searched for immunogenicity data of TNFα or CD20 inhibitor biosimilars or biosimilar candidates. Data collected included the proportion of patients positive for anti-drug antibodies (ADAbs), proportion with neutralizing antibodies (nAbs) among ADAb-positive patients, ADAb/nAb assay characteristics, cross-reactivity, and the effects of ADAbs on pharmacokinetics, pharmacodynamics, efficacy, and safety. We identified eight biosimilars or biosimilar candidates for adalimumab (BI 695501, SB5, ABP 501, GP2017, PF-06410293, MSB-11022, FKB-327, ZRC-3197) four for etanercept (SB4, GP2015, CHS-0214, LBEC0101), and three each for infliximab (SB2, CT-P13, GP1111) and rituximab (CT-P10, GP2013, PF-05280586) with immunogenicity data. Randomized, head-to-head trials with reference products varied in design and methodology of ADAb/nAb detection. The lowest proportions of ADAb-positive (0–13%) and nAb-positive patients (0–3%) were observed in the trials of etanercept and its biosimilars, and the highest with adalimumab, infliximab, and their biosimilars (ADAbs: ≤ 64%; nAbs: ≤ 100%). The most common method of ADAb detection was electrochemiluminescence, and ADAb positivity was associated with nominally inferior efficacy and safety. Overall, there were no significant immunogenicity differences between biosimilars and reference products. However, there are many discrepancies in assessing and reporting clinical immunogenicity. In conclusion, immunogenicity data of biosimilars or biosimilar candidates for TNFα or CD20 inhibitors were collected in trials that varied in design and procedures for ADAb/nAb detection. In general, immunogenicity parameters of biosimilars are similar to those of their reference products.

Impact of immunogenicity on efficacy and tolerability of tumour necrosis factor inhibitors: pooled analysis of biosimilar studies in rheumatoid arthritis

Objective: SB4, SB2, and SB5 are biosimilars of etanercept (ETN), infliximab (INF), and adalimumab (ADA), respectively. This pooled analysis evaluated the immunogenicity of these treatments across three phase III randomized controlled trials of patients with rheumatoid arthritis (RA). Methods: Patients had to have at least one anti-drug antibody (ADAb) assessment up to the time of the primary endpoint from each study (week 24 in SB4 and SB5 studies; week 30 in SB2 study). The effect of ADAbs on American College of Rheumatology 20% (ACR20) response and the incidences of injection-site reactions (ISRs)/infusion-related reactions (IRRs) were evaluated. Results: The study included 1709 patients. The cumulative incidences of ADAbs were 30.3% in the all-treatments-combined group, 29.1% in the biosimilars combined group, and 31.5% in the reference products combined group. ACR20 response rates were significantly lower in ADAb-positive patients in the all-treatments-combined [odds ratio (95% confidence interval) 1.77 (1.37, 2.27), p < 0.0001], biosimilars combined [2.24 (1.53, 3.30), p < 0.0001], and reference products combined [1.49 (1.06, 2.09), p = 0.0225] groups. ADAb-positive patients also had a higher likelihood of developing ISRs/IRRs in the all-treatments-combined group [0.56 (0.31, 1.01), p = 0.0550], predominantly due to the results observed with SB2 + INF combined rather than with SB4 + ETN or SB5 + ADA combined. Conclusion: In this pooled analysis, ADAbs were associated with reduced efficacy in patients with RA treated with biosimilars (SB4, SB2, and SB5) or their reference products (ETN, INF, and ADA). ADAbs were associated with an increased incidence of ISRs/IRRs in those treated with SB2 + INF. Clinical trial registration numbers: NCT01936181 (SB2 study), NCT01895309 (SB4 study), and NCT02167139 (SB5 study).

LBEC0101, an etanercept biosimilar for the treatment of rheumatoid arthritis

Introduction: Treatment of rheumatoid arthritis (RA) has been revolutionized by the introduction of biologic disease-modifying antirheumatic drugs, such as tumor necrosis factor (TNF) inhibitors. With patent expiry approaching for many expensive biologic molecules, such as etanercept, more affordable biosimilar drugs are being developed. LBEC0101 is an etanercept biosimilar approved in Japan and South Korea for all etanercept indications including RA. Areas covered: We discuss the pharmacological characteristics, pharmacokinetics, efficacy, and safety of LBEC0101 compared with the etanercept reference product (ETN-RP). Preclinical studies showed that the binding affinity to TNFα and biological activity of LBEC0101 were similar to those of the ETN-RP. The pharmacokinetic profile of LBEC0101 was also similar to that of the ETN-RP. A Phase III, randomized, double-blind, 54-week study showed that the efficacy of LBEC0101 was equivalent to that of the ETN-RP in RA patients. An extension study showed that efficacy was sustained long-term in patients receiving LBEC0101 and in those switching from the ETN-RP to LBEC0101. The safety profile of LBEC0101 was also confirmed to be comparable with the ETN-RP. Expert opinion: LBEC0101 has shown equivalent pharmacokinetics and efficacy and comparable safety to the ETN-RP, and the lower cost of LBEC0101 provides a good cost-benefit ratio.

Nocebos in rheumatology: emerging concepts and their implications for clinical practice

Nocebo effects are noxious reactions to therapeutic interventions that occur because of negative expectations of the patient. In the past decade, neurobiological data have revealed specific neural pathways induced by nocebos (that is, interventions that cause nocebo effects), as well as the associated mechanisms and predisposing factors of nocebo effects. Epidemiological data suggest that nocebos can have a notable effect on medication adherence, clinical outcomes and health-care policy. Meta-analyses of randomized controlled trials (RCTs) of patients with rheumatic and musculoskeletal diseases (RMDs) indicate that withdrawal of treatment by placebo-arm participants owing to adverse events is common; a proportion of these events could be nocebo effects. Moreover, in large-scale, open-label studies of patients with RMDs who transition from bio-originator to biosimilar therapeutics, biosimilar retention rates were much lower than in previous double-blind switch RCTs. This discrepancy suggests that in addition to the lack of response in some patients because of intrinsic differences between the drugs, nocebos might have an important role in low biosimilar retention, thus increasing the need for awareness and early identification of nocebo effects by rheumatologists and allied health-care professionals.

Era of biosimilars in rheumatology: reshaping the healthcare environment

Compared with the original approved biological drug on which it is based, a biosimilar has highly similar physicochemical characteristics and biological activity, as well as equivalent efficacy and no clinically meaningful differences in safety and immunogenicity. Before they are approved, biosimilars must undergo a rigorous development process using state-of-the-art technologies to establish biosimilarity to the reference biological product. After approval, biosimilars must comply with good pharmacological practices for biological drugs. Several biosimilar disease-modifying antirheumatic drugs (bsDMARDs) based on the tumour necrosis factor inhibitors adalimumab, etanercept and infliximab have been approved for use in patients with rheumatic diseases. Substantial cost savings can be made if biological-naive patients begin treatment with bsDMARDs, and patients receiving original biological DMARDs (bDMARDs) are switched to bsDMARDs. Despite the consistently similar efficacy, safety and immunogenicity of bsDMARDs relative to their respective original bDMARDs, switching from a reference bDMARD to a bsDMARD can result in nocebo responses, such as subjective increase of disease activity and pain-related adverse events. This may have a negative impact on adherence to bsDMARDs in clinical trials and clinical practice. To ensure optimal and rational integration of bsDMARDs into rheumatology practice and realise the full cost-saving efficacy of these drugs, rheumatologists must be aware that careful communication of the cost-saving efficacy and safety of bsDMARDs to their patients is the key to a successful long-term switch to bsDMARD therapy.

Anti-TNF biosimilars in psoriasis: from scientific evidence to real-world experience

Tumor necrosis factor (TNF) inhibitors account for a large proportion of drugs used to treat psoriasis and are indicated first-line options in certain settings. Several biosimilar drugs based on the anti-TNF agents adalimumab, infliximab, and etanercept are now available for use in patients with psoriasis. The favorable cost differential of biosimilars is expected to improve access to biologic therapy for biologic-naive psoriasis patients, who are often undertreated. Also, substantial cost savings can be made if patients are switched to biosimilars. To date, most clinical testing of anti-TNF biosimilars approved for use in psoriasis has been performed in patients with rheumatoid arthritis, and the results extrapolated to psoriasis. Although this may initially raise concerns for clinicians looking to start their psoriasis patients on biologic treatment with a biosimilar or switch from an original biologic to a biosimilar, the process of extrapolation is tightly regulated and scientifically justified. Furthermore, available real-world evidence of the safety and efficacy of anti-TNF agents in patients with psoriasis complements clinical trial data in patients with rheumatoid arthritis. When equipped with the appropriate knowledge, clinicians should have confidence to use biosimilars for the treatment of psoriasis.

Review of Biosimilar Trials and Data on Etanercept in Rheumatoid Arthritis

PURPOSE OF REVIEW

Etanercept was the first tumour necrosis factor inhibitor approved to treat rheumatoid arthritis (RA) in the United States (US) and Europe. The recent patent expiration of the etanercept originator ENBREL in Europe has facilitated the development of biosimilar products, creating the prospect of reduced treatment costs. In this article, we review the original trials for etanercept in RA to facilitate critical appraisal of biosimilar trial data.

RECENT FINDINGS

Two etanercept biosimilars are currently approved in Europe and/or the US, SB4 (Benepali) and GP2015 (Erelzi), having met the pre-specified equivalence criteria for biosimilarity. Trial data demonstrates subtle differences in clinical outcomes and adverse events between the biosimilars and the reference product (RP). The development of etanercept biosimilars may reduce the financial burden of treating RA, but real-world data regarding efficacy and safety in comparison to the RP will be vital to assess for meaningful differences.