Long-term Efficacy, Safety, and Immunogenicity of the Infliximab (IFX) Biosimilar, PF-06438179/GP1111, in Patients with Rheumatoid Arthritis After Switching from Reference IFX or Continuing Biosimilar Therapy: Week 54-78 Data From a Randomized, Double-Blind, Phase III Trial

Infliximab biosimilar GP1111: a review of 5 years' post-approval experience

INTRODUCTION

Infliximab is a chimeric monoclonal antibody against tumor necrosis factor alpha, and GP1111 (Zessly®, Sandoz) is the most recently approved infliximab biosimilar in Europe. We reviewed the approval process and key evidence for GP1111, focusing primarily on the indications of rheumatoid arthritis (RA) and inflammatory bowel disease (IBD).

AREAS COVERED

This narrative review discusses preclinical, clinical, and real-world data for GP1111.

EXPERT OPINION

Results from the Phase III REFLECTIONS trial in patients with moderate-to-severe active RA despite methotrexate therapy confirmed the similarity in efficacy and safety between GP1111 and reference infliximab. Switching from reference infliximab to GP1111 in REFLECTIONS had no impact on efficacy or safety. Since the European approval of GP1111 in March 2018, real-world data have also confirmed the efficacy and safety of switching from another infliximab biosimilar to GP1111 in patients with RA and IBD. In addition, budget impact analysis of various sequential targeted treatments in patients with RA found that GP1111 was cost-effective when used early after failure of conventional synthetic disease-modifying antirheumatic drugs. Therefore, 5 years' post-approval experience with GP1111 in RA and IBD, and key clinical and real-world evidence, support the safety and efficacy of continued use of GP1111 in all infliximab-approved indications.

Assessing MAPPs assay as a tool to predict the immunogenicity potential of protein therapeutics

MHC-II-associated peptide proteomics (MAPPs) is a mass spectrometry-based (MS) method to identify naturally presented MHC-II-associated peptides that could elicit CD4+T cell activation. MAPPs assay is considered one of the assays that better characterize the safety of biotherapeutics by driving the selection of the best candidates concerning their immunogenicity risk. However, there is little knowledge about the impact of bead material on the recovery of MHC-II MS-eluted ligands in MAPPs assays. Here, we firstly describe a robust MAPPs protocol by implementing streptavidin magnetic beads for the isolation of these peptides instead of commonly used NHS-activated beads. Moreover, we assessed the impact of the cell medium used for cell cultures on the morphology and recovery of the in vitro-generated APCs, and its potential implications in the amount of MHC-II isolated peptides. We also described an example of a MAPPs assay application to investigate drug-induced immunogenicity of two bispecific antibodies and compared them with monospecific trastuzumab IgG1 control. This work highlighted the importance of MAPPs in the preclinical in vitro strategy to mitigate the immunogenicity risk of biotherapeutics.

Safety outcomes when switching between biosimilars and reference biologics: A systematic review and meta-analysis

Biosimilars are increasingly available for the treatment of many serious disorders, however some concerns persist about switching a patient to a biosimilar whose condition is stable while on the reference biologic. Randomized controlled studies and extension studies with a switch treatment period (STP) to or from a biosimilar and its reference biologic were identified from publicly available information maintained by the U.S. Food and Drug Administration (FDA). These findings were augmented with data from peer reviewed publications containing information not captured in FDA reviews. Forty-four STPs were identified from 31 unique studies for 21 different biosimilars. Data were extracted and synthesized following PRISMA guidelines. Meta-analysis was conducted to estimate the overall risk difference across studies. A total of 5,252 patients who were switched to or from a biosimilar and its reference biologic were identified. Safety data including deaths, serious adverse events, and treatment discontinuation showed an overall risk difference (95% CI) of -0.00 (-0.00, 0.00), 0.00 (-0.01, 0.01), -0.00 (-0.01, 0.00) across STPs, respectively. Immunogenicity data showed similar incidence of anti-drug antibodies and neutralizing antibodies in patients within a STP who were switched to or from a biosimilar to its reference biologic and patients who were not switched. Immune related adverse events such as anaphylaxis, hypersensitivity reactions, and injections site reactions were similar in switched and non-switched patients. This first systematic review using statistical methods to address the risk of switching patients between reference biologics and biosimilars finds no difference in the safety profiles or immunogenicity rates in patients who were switched and those who remained on a reference biologic or a biosimilar.

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.

Efficacy and Safety of CMAB008 Compared with Innovator Infliximab in Patients with Moderate-to-Severe Rheumatoid Arthritis Receiving Concomitant Methotrexate: A Randomized, Double-blind, Multi-center, Phase III Non-inferiority Study

OBJECTIVES

The aim of this work is to verify the non-inferior efficacy and safety of CMAB008 compared with innovator infliximab in rheumatoid arthritis patients combined with methotrexate.

METHODS

We conducted a randomized, double-blinded, parallel, positive control design, multicenter study, with a stable dose of methotrexate. Patients were enrolled randomly with a ratio of 1:1 to receive intravenously CMAB008 3 mg/kg or innovator infliximab 3 mg/kg at weeks 0, 2, 6, 14, 22 and 30. The primary efficacy endpoint was American College of Rheumatology 20% improvement criteria (ACR20) response rate at week 30. The non-inferiority was established if the lower limit of the one-sided 97.5% confidence interval (CI) for the difference was more than - 15% and the equivalence was established if the two-sided 95% CI was within ± 15% in an exploratory equivalence analysis. The secondary endpoints included other efficacy assessment parameters, as well as immunogenicity, safety, and pharmacokinetics.

RESULTS

In the full analysis population (FAS), 110 (57.6%) of 191 patients in the CMAB008 group and 120 (62.2%) of 193 patients in the innovator infliximab group reached the primary outcome of ACR20 at week 30. The differences of the rates were - 4.6% and the lower limit of one-sided 97.5% confidence interval was - 14.29%, not less than the lower limit of the non-inferiority margin (- 15%); so CMAB008 was non-inferior to innovator infliximab. Further, CMAB008 was equivalent to innovator infliximab both in FAS (difference - 4.6%, 95% CI - 14.29% to 5.12%) and PPS (difference - 3.3%, 95% CI - 13.18% to 6.62%). The efficacy, safety, immunogenicity, and pharmacokinetics are highly similar between CMAB008 and innovator infliximab.

CONCLUSIONS

Non-inferior efficacy of CMAB008 to innovator infliximab is illustrated with similar early and lasting therapeutic effects, and the equivalence is further demonstrated. CMAB008 is well tolerated and has semblable safety compared with the innovator infliximab.

TRIAL REGISTRATION NUMBER

NCT03478111.

Use of multibiomarker disease activity scores in biosimilarity studies for the treatment of patients with rheumatoid arthritis

Objectives

This exploratory analysis investigated the potential use of the multibiomarker disease activity (MBDA) score to support biosimilarity assessments using data from two randomised controlled trials (RCTs) of biosimilar infliximab (IFX-qbtx) and biosimilar adalimumab (ADL-afzb) versus EU-sourced infliximab (Remicade; IFX-EU) and adalimumab (Humira; ADL-EU) reference products, respectively, both conducted in adult patients with active rheumatoid arthritis.

Methods

In one study, patients (N=650) were randomised 1:1 to IFX-qbtx or IFX-EU (3 mg/kg intravenous at weeks 0, 2 and 6, then every 8 weeks). In the other, patients (N=597) were randomised 1:1 to ADL-afzb or ADL-EU (40 mg subcutaneous every other week). All treatments were given with MTX. Mean values of MBDA scores were calculated at baseline (BL), based on the concentrations of 12 serum proteins using the Vectra disease activity algorithm, and at timepoints throughout treatment period 1 (TP1) of the IFX (weeks 6, 14, 30) and ADL (weeks 6, 12, 26) studies. Data were summarised using descriptive statistics for the intent-to-treat population, without imputation for missing data.

Results

At BL, mean (±SD) MBDA scores were 61.3 (±12.5) and 58.8 (±13.2) for IFX-qbtx (n=236) and IFX-EU (n=248), respectively, and 57.2 (±14.44) and 58.3 (±15.34) for ADL-afzb (n=292) and ADL-EU (n=293), respectively. Mean MBDA scores were highly comparable between IFX-qbtx and IFX-EU and between ADL-afzb and ADL-EU at all measured timepoints during TP1 in each study.

Conclusions

These RCTs are the first to incorporate MBDA score as an exploratory assessment of biosimilarity. MBDA scores may provide objective, quantitative evidence of biosimilarity using an assessment of disease activity that is independent of the potential subjectivity inherent in joint counts, or in patient or physician global assessments.

Trial registration numbers

NCT02222493 and NCT02480153.

Regulatory Evaluation of Biosimilars: Refinement of Principles Based on the Scientific Evidence and Clinical Experience

The World Health Organization (WHO) guidelines on evaluation of similar biotherapeutic products (SBPs; also called biosimilars) were adopted by the WHO Expert Committee on Biological Standardization (ECBS) in 2009. In 2019, the ECBS considered that a more tailored and potentially reduced clinical data package may be acceptable in cases where this was clearly supported by the available scientific evidence. The goal of this publication is to review the current clinical experience and scientific evidence and to provide an expert perspective for updating the WHO guidelines to provide more flexibility and clarity. As the first step, the relevant guidelines by other regulatory bodies were reviewed in order to identify issues that might help with updating the WHO guidelines. Next, a literature search was conducted for information on the long-term efficacy, safety, and immunogenicity of biosimilars to identify possible long-term problems. Finally, a search for articles concerning the role of clinical studies in the benefit-risk evaluation of biosimilars was conducted. The analysis of other guidelines suggested that the WHO guidelines may need more emphasis on the importance of the state-of-the-art physicochemical and structural comparability exercise and in vitro functional testing. The use of "foreign" reference product will also need clarifications. The value of in vivo toxicological tests in the development of biosimilars is questionable, and the non-clinical part needs revisions accordingly. The concepts of "totality of evidence," "stepwise development," and "residual uncertainty" were applied in the evaluation of the clinical sections of the guideline. The review of long-term safety and efficacy demonstrated the robustness of the current biosimilar development concept. The analysis of the roles of different development phases suggested that the large efficacy, safety, and immunogenicity studies are, in most cases, redundant. The residual uncertainty of safety, immunogenicity, and efficacy of biosimilars that has shaped the current regulatory guidelines is now substantially reduced. This will allow the re-evaluation of the non-clinical and clinical requirements of the current WHO main guideline. The shift of the relative impact of the development phases towards physico-chemical and in vitro functional testing will provide a relief to the manufacturers and new challenges to the regulators.

Budget Impact of Sequential Treatment with Biologics, Biosimilars, and Targeted Synthetic Disease-Modifying Antirheumatic Drugs in Thai Patients with Rheumatoid Arthritis

BACKGROUND

Targeted treatment of rheumatoid arthritis (RA) includes biological DMARDs (bDMARDs) and JAK inhibitors (JAKi). These agents are recommended at the same level on the basis of their efficacy and safety data. However, no local evidence of the impact of RA treatment regimens on total budget spending is available to date. This study aimed to explore the budget impact of different sequential targeted treatments in Thai patients with RA who failed at least three conventional synthetic DMARDs.

METHODS

We used the adapted model to evaluate the budget impact of adding tofacitinib in different order to RA targeted treatment regimens. The Thai RA population eligible for treatment was assessed on the basis of local prevalence and experts' opinion. Cost-impact analysis was evaluated for the treatment sequences of four different lines of targeted therapies using inputs like clinical efficacy, safety, and costs. The model used a decision tree structure with treatment nodes corresponding to treatment response outcomes for a cohort of patients. The comparisons included five bDMARDs [etanercept (ETN), infliximab (IFX), golimumab (GOL), rituximab (RTX), tocilizumab (TCZ) intravenous formulation], two JAKi [tofacitinib (TOF) and baricitinib (BAR)], and two IFX biosimilars (PF-06438179/GP1111 and CT-P13). A total of 80 treatment sequences within each containing four sequential first-, second-, third-, and fourth-line options were generated.

RESULTS

The findings of the base case scenario indicated the treatment sequence with RTX as first-line, followed by IFX biosimilar (PF-06438179/GP1111), TOF, and TCZ, respectively, produced the lowest budget impact of US $693.54 million. Sensitivity analyses confirmed the robustness of our findings.

CONCLUSION

The order of targeted therapy starting with RTX, then IFX biosimilar, TOF, and finally TCZ incurred the lowest budget impact over a 5-year time horizon for treating moderate to severe RA. Our findings may help payers and policy makers consider appropriate budget allocation on chronic non-communicable diseases, especially RA.

Real-world observational study of biosimilars in inflammatory arthritis treatment: a systematic literature review

INTRODUCTION

The use of biological agents in patients with rheumatic diseases has achieved the therapeutic target, i.e., remission or low disease activity. The share of biological agents has been growing with the approval of biosimilars, which have been recognized for their equivalent efficacy, safety, pharmacokinetics, and immunogenicity to the original as well as their reduced economic burden.

AREA COVERED

Biosimilars are being examined for their bioequivalence to reference products in randomized-controlled trials; however, the use of biosimilars in actual clinical practice is complicated owing to issues with switching and comorbidities. Therefore, this review describes real-world data in the rapidly evolving field of biosimilars in the treatment of rheumatoid arthritis and spondyloarthropathy, including ankylosing spondylitis and psoriatic arthritis.

EXPERT OPINION

According to published data, the use of biosimilars for inflammatory arthritis led to no significant inferiority in treatment outcomes and resulted in considerable cost savings in the real-world. Currently, beyond the use of biosimilars, issues with the interchangeability of biosimilars, including immunogenicity, should be addressed. Strategies to overcome these concerns will improve treatment efficacy and safety in patients with inflammatory arthritis.