Rituximab biosimilars in hematologic malignancies: the need for a real-world approach

The landscape of real-world evidence of rituximab utilization and clinical outcomes in patients with cancer, rheumatoid arthritis, and multiple sclerosis: A scoping review

BACKGROUND

Rituximab (RTX) is an anti-CD20 monoclonal antibody that is used to treat various conditions in cancer, rheumatoid arthritis (RA), and multiple sclerosis (MS). Although RTX has been used in the United States for almost 3 decades, questions remain regarding its real-world utilization and effectiveness.

OBJECTIVE

To describe the state of observational research and real-world evidence evaluating RTX in oncology, RA, and off-label use in MS.

METHODS

A broad search was conducted in MEDLINE, Embase, and CINAHL covering the period of January 2010 to June 2022. Two reviewers independently screened all identified records for each disease category (cancer, RA, MS) beginning with title review, followed by abstract, and full-text review to identify relevant publications to include in the final analysis. Data were extracted and summarized for each disease based on overall trends, similarities, and differences across included studies and stratified by disease state.

RESULTS

A total of 260 studies met eligibility criteria, with 79 studies for the RA cohort, 144 for cancer, and 37 for MS. Across all disease cohorts, most studies (n = 189; 72.7%) were retrospective. 171 (65.8%) studies used hospital or electronic health record data as their data source and 65 (23.2%) used registry databases. Most studies (n = 153; 58.8%) assessed the effectiveness of RTX measured by disease-specific endpoints, followed by safety (n = 60; 23.1%), treatment patterns (n = 32; 12.3%), and descriptive analyses assessing treatment adherence and economic burden of disease (n = 16; 6.2%). Although safety was not the primary outcome for most studies, the majority of studies across all disease states still reported some form of safety measure. Conclusive statements on RTX's benefit varied across disease states, with MS having the most (n = 30; 81.1%) studies suggesting the drug's positive benefit. There were limited studies assessing RTX use, associated economic burden, and biosimilar switching.

CONCLUSIONS

The findings underscore the need for health care providers to better understand the treatment landscape and utilization of RTX, particularly in terms of patient selection, timing of initiation, and long-term outcomes. Real-world evidence can help support health care decisions and treatment using rituximab.

Real-world outcomes of diffuse large B-cell lymphoma in the biosimilar era

Background

Diffuse large B-cell lymphoma (DLBCL) is an aggressive and the most common type of non-Hodgkin lymphoma (NHL). The clinical use of rituximab has improved the treatment response and survival of patients with DLBCL. The introduction of rituximab biosimilar into healthcare system has helped in providing a cost-effective treatment to B-cell lymphoid malignancies as standard of care and has improved access to patients worldwide. The aim of this study was to observe the real-world effectiveness and safety of Reditux™ and Ristova® in DLBCL patients.

Methods

Observational study in adults with DLBCL receiving Reditux™ or Ristova® across 29 centers in India (2015-2022). Effectiveness and safety were assessed up to 2 years after first dose.

Results

Out of 1,365 patients considered for analysis, 1,250 (91.6%) were treated with Reditux™ and 115 (8.42%) with Ristova®. At 2 years, progression-free survival (PFS) 69% [hazard ratio (HR), 1.16; 95% CI, 0.80-1.67], overall survival (OS) 78.7% (HR, 1.20; 95% CI, 0.78-1.86), response rates, quality of life (QoL), and overall safety in both the cohorts were comparable. The best overall response rate (BORR) at 6 months was comparable with no statistically significant differences between the Reditux™ and the Ristova® cohorts (89.2% vs. 94.3%). In multivariate analysis, BCL-2 and VAS were significant prognostic factors for PFS.

Conclusion

Reditux™ and Ristova® were comparable in real-world setting.

Clinical Trial Registration

ISRCTN registry, identifier (ISRCTN13301166).

Therapeutic Antibodies in Medicine

Antibody engineering has developed into a wide-reaching field, impacting a multitude of industries, most notably healthcare and diagnostics. The seminal work on developing the first monoclonal antibody four decades ago has witnessed exponential growth in the last 10-15 years, where regulators have approved monoclonal antibodies as therapeutics and for several diagnostic applications, including the remarkable attention it garnered during the pandemic. In recent years, antibodies have become the fastest-growing class of biological drugs approved for the treatment of a wide range of diseases, from cancer to autoimmune conditions. This review discusses the field of therapeutic antibodies as it stands today. It summarizes and outlines the clinical relevance and application of therapeutic antibodies in treating a landscape of diseases in different disciplines of medicine. It discusses the nomenclature, various approaches to antibody therapies, and the evolution of antibody therapeutics. It also discusses the risk profile and adverse immune reactions associated with the antibodies and sheds light on future applications and perspectives in antibody drug discovery.

A place for biosimilars in the changing multiple sclerosis treatment landscape

BACKGROUND

The treatment paradigm for multiple sclerosis (MS), particularly relapsing-remitting MS, is heavily reliant on biologic disease-modifying therapies (DMTs). However, the current cost of treatment acts as a significant barrier to access for patients. Over the next few years exclusivity periods for key biologic medicines used in MS are likely to end, opening the door for biosimilar medicines to enter the market.

METHODS

In this review, we discuss what biosimilar medicines are, and how the existing experience with biosimilar medicines across multiple therapy areas can inform the assimilation of biosimilar medicines into the MS treatment landscape in Europe and the US.

RESULTS

There is currently a lack of knowledge and awareness around the distinctions and similarities between small molecules, non-biological complex drugs, and biological medicines, as well as the different categories of follow-on successor medicines. These include biosimilar medicines that offer a matching efficacy and safety profile to the reference biologic. Understanding and recognition of the stringency of the approval pathways required for drug categories such as biosimilars are key in building confidence in treatment outcomes. For example, biosimilar medicines are sometimes perceived only as 'copies' of their reference biologic despite undergoing an extensive approval process requiring that no clinically meaningful differences are observed between the biosimilar medicine and the reference medicine. For MS, introduction of biosimilar medicines in the future will enable more people with MS to receive effective treatment, and also expand access to biologic DMTs in MS. Experiences from the use of biosimilars in multiple therapy areas have shown us that this can result in cost-saving benefits for a healthcare system. Introduction of biosimilar medicines in other therapy areas has also demonstrated the importance of appropriate, accurate education and information for their successful integration into clinical practice.

CONCLUSION

In order to realize optimized treatment outcomes in MS in coming years and to find the appropriate place for biosimilar medicines in the changing MS landscape, it is essential that clinicians and people with MS understand the fundamentals of biosimilars, their potential benefits and consistency of treatment provided by a biosimilar medicine, given the matching efficacy and safety profile to its reference medicine. As evidenced in other therapy areas, biosimilar medicines may reduce key barriers to access by providing a cost-effective alternative to the MS treatment arsenal, while providing the same treatment outcomes as reference biologics.

COVID-19 disease frequency, risk factors, and re-infection rates in patients with autoimmune rheumatic disease receiving rituximab

INTRODUCTION

Rituximab, which is used in autoimmune rheumatic diseases (ARD), can cause both an increased risk of development of COVID-19 disease and re-infection due to its potent and long-acting immunosuppression. So, we aimed to evaluate the frequency, risk factors and re-infection rates of COVID-19 in ARD patients receiving rituximab.

METHODS

A single-center retrospective study was performed with patients receiving rituximab for ARD in 12 months before the onset of COVID-19 in Turkey. The data regarding severe acute respiratory syndrome-coronavirus 2 reverse transcription polymerized chain reaction (RT-PCR) test, clinical, laboratory, and mortality data of all patients were collected from medical records. Logistic regression analysis was used for predictors of COVID-19 disease. COVID-19 re-infection was defined as RT-PCR positivity and recurrence of acute COVID-19 symptoms after at least 1 negative RT-PCR in patients with clinical improvement.

RESULTS

Ninety-eight ARD patients with rituximab were evaluated and 23 (23%) of them had COVID-19. The presence of hypogammaglobulinemia increased the risk of COVID-19 disease 8-fold. COVID-19 pneumonia occurred in 13 (57%) and these patients' age was higher than those without pneumonia (59.6 ± 11.8 vs 44.9 ± 14.2 years, P = 0.013). Mortality due to COVID-19 was 13% and COVID-19 re-infection was seen in 20% of survivors.

CONCLUSION

Regardless of the underlying rheumatic disease and organ involvements, hypogammaglobulinemia in ARD could be a risk factor for COVID-19 development, and advanced age could be for COVID-19 severity. Moreover, COVID-19 re-infection rates are high.

Severe Hypersensitivity Reactions at Biosimilar versus Originator Rituximab Treatment Initiation, Switch and Over Time: A Cohort Study on the French National Health Data System

BACKGROUND

Biosimilar products of rituximab came to market in 2017. French pharmacovigilance centers have highlighted an excess of case reports of severe hypersensitivity reactions related to their use compared with the originator product.

OBJECTIVE

The aim of this study was to assess the real-world association between biosimilar versus originator rituximab injections and hypersensitivity reactions, among initiators and switchers, at first injection and over time.

METHODS

The French National Health Data System was used to identify all rituximab users between 2017 and 2021. A first cohort consisted of patients who initiated rituximab (originator or biosimilar), while a second cohort consisted of originator-to-biosimilar switchers, matched on age, sex, deliveries history, and pathology, with one or two patients still receiving the originator product. The event of interest was defined as a hospitalization for anaphylactic shock or serum sickness following a rituximab injection.

RESULTS

A total of 91,894 patients were included in the initiation cohort-17,605 (19%) with the originator product and 74,289 (81%) with a biosimilar. At initiation, 86/17,605 (0.49%) and 339/74,289 (0.46%) events occurred in the originator and biosimilar groups, respectively. The adjusted odds ratio of biosimilar exposure associated with the event was 1.04 (95% confidence interval [CI] 0.80-1.34), and the adjusted hazard ratio for biosimilar versus originator exposure was 1.15 (95% CI 0.93-1.42), showing no increased risk of event with biosimilar use at first injection, and over time. 17,123 switchers were matched to 24,659 non-switchers. No association was found between switch to biosimilars and occurrence of the event.

CONCLUSION

Our study does not support any association between exposure to rituximab biosimilars versus originator and hospitalization for a hypersensitivity reaction, either at initiation, at switch, or over time.

A Developer's Perspective on Clinical Evidence and Benefits for Rituximab Biosimilar Uptake, with a Focus on CT-P10

To date, four rituximab biosimilars have received regulatory approval from the European Medicines Agency and/or US Food and Drug Administration. CT-P10 was the first rituximab biosimilar to be approved by each agency, in 2017 and 2018, respectively. Regulatory approval of CT-P10 followed demonstration of pharmacokinetic equivalence to the reference product in a phase I study in patients with rheumatoid arthritis. Phase III pivotal studies of CT-P10 subsequently demonstrated equivalence or non-inferiority of pharmacokinetics and efficacy between CT-P10 and reference rituximab in patients with rheumatoid arthritis, advanced-stage follicular lymphoma, and low-tumour-burden follicular lymphoma. Almost 5 years after its initial regulatory approval, significant real-world experience has accumulated with CT-P10 use, particularly in diffuse large B-cell lymphoma, one of the indications approved by extrapolation. This article summarises the pivotal data underlying regulatory approval for the four licensed rituximab biosimilars, before focusing on real-world data gathered with CT-P10. These data provide further support for the safety and effectiveness of CT-P10 and should boost healthcare professional and patient confidence in its use. Pharmacoeconomic analyses support the potential healthcare system cost savings offered by rituximab biosimilar uptake, which could lead to improved patient access to biologic treatments. Opportunities arising from biosimilar uptake extend further, potentially enabling innovative investigator-led research and therapeutic advances.

Analytical similarity as base for rituximab biosimilars in lymphoid malignancies in the clinic: a PF-05280586 case study

The availability of biosimilars in oncology has provided an opportunity for increased patient access to biologic therapies. However, healthcare professional perceptions concerning the relatively limited clinical data sufficient to support their regulatory approval may contribute to varied uptake and use. We review key aspects of the development program for the rituximab biosimilar PF-05280586 (Ruxience™) that supported its approval for lymphoid malignancies, to illustrate the rationale for an abbreviated clinical program. In particular, we describe the extensive analytical assessment, comprising sensitive techniques that established similarity with the reference product in key product attributes, underlying structure, function, potency, safety and quality, which formed the foundation for a successful development program, culminating in a confirmatory comparative clinical trial in patients with follicular lymphoma.

FDA-Approved Drugs for Hematological Malignancies-The Last Decade Review

Simple Summary

Hematological malignancies are diseases involving the abnormal production of blood cells. The aim of the study is to collect comprehensive information on new drugs used in the treatment of blood cancers which have introduced into therapy in the last decade. The approved drugs were analyzed for their structures and their biological activity mechanisms.

Abstract

Hematological malignancies, also referred to as blood cancers, are a group of diseases involving abnormal cell growth and persisting in the blood, lymph nodes, or bone marrow. The development of new targeted therapies including small molecule inhibitors, monoclonal antibodies, bispecific T cell engagers, antibody-drug conjugates, recombinant immunotoxins, and, finally, Chimeric Antigen Receptor T (CAR-T) cells has improved the clinical outcomes for blood cancers. In this review, we summarized 52 drugs that were divided into small molecule and macromolecule agents, approved by the Food and Drug Administration (FDA) in the period between 2011 and 2021 for the treatment of hematological malignancies. Forty of them have also been approved by the European Medicines Agency (EMA). We analyzed the FDA-approved drugs by investigating both their structures and mechanisms of action. It should be emphasized that the number of targeted drugs was significantly higher (46 drugs) than chemotherapy agents (6 drugs). We highlight recent advances in the design of drugs that are used to treat hematological malignancies, which make them more effective and less toxic.

Evolving Perceptions, Utilization, and Real-World Implementation Experiences of Oncology Monoclonal Antibody Biosimilars in the USA: Perspectives from Both Payers and Physicians

BACKGROUND

The adoption of oncology biosimilars has been slow in the USA, which may be attributed in part to stakeholder perceptions and lack of operational guidance that supports favorable access to biosimilars.

OBJECTIVE

Our objective was to understand the real-world implementation experiences with oncology biosimilars of US payers and healthcare professionals (HCPs) as their experience with biosimilars has evolved.

METHODS

In-depth qualitative interviews with payers (n = 20) and HCPs (n = 17 physicians, n = 3 practice managers) were conducted. Payers included managed care organizations (MCOs), integrated delivery networks, and pharmacy benefit managers (PBMs). Physicians were affiliated with a healthcare network or were community based, specialized in hematology/oncology, and had prescribed oncology biosimilars. Audio transcripts of the interviews were coded using MaxQDA software to enable descriptive analysis of the qualitative data.

RESULTS

Over 80.0% of physicians perceived the efficacy and safety of biosimilars to be highly comparable to that of originators. Up to 87.5% of physicians reported using biosimilars in > 50% of their treatment-naïve patients and were comfortable using biosimilars in all approved indications. To encourage utilization, 75.0% of MCOs/PBMs preferred biosimilars over originators in treatment-naïve patients and implementation via step therapy. Physician involvement in choosing biosimilars was minimal, which was largely dependent on practice protocols or insurance preferences. The major factor influencing payers' coverage decisions and biosimilar adoption was potential cost savings.

CONCLUSIONS

US payers and physicians who have experience with biosimilars have favorable views of oncology biosimilars, particularly for treatment-naïve patients. A framework for integrating biosimilars into oncology practice is developing, primarily driven by insurance coverage, contracting, and cost benefits.

Progress in oncology biosimilars till 2020: Scrutinizing comparative studies of biosimilar monoclonal antibodies

Stupendous elevation in the healthcare costs has followed with the inception of the current unconventional options of treatment available for cancer patients. There is a dire need of innovative financing approaches to lessen the financial load on healthcare system. Biosimilars are biological drugs consisting of an active ingredient from a reference biological drug that has a great potential of relieving financial load. Strict requirements from regulatory point of view are required as biosimilars are exceedingly similar to but not identical to the reference product. This provides with a certainty that no consequential differences from clinical point of view as compared to the respective biologics exists with regards to efficacy, safety and purity. Safety and effectiveness of biosimilars have been disclosed since more than 10 years of affirmations. However, there is a need to educate the healthcare professionals to abolish potential misconceptions and coalesce biosimilars into regular clinical practice. The present review focuses on providing an overview of regulatory aspects and requirements for biosimilars, the main challenges in the selection and development of biosimilars and the economic impact and financial savings observed in recent studies carried out in different parts of the world. In addition, we have discussed the different successful comparative studies which have been done in different parts of the world to depict the biosimilarity for monoclonal antibodies such as bevacizumab, trastuzumab and rituximab.