Risk management of biosimilars in oncology: each medicine is a work in progress

Factors Associated with Biosimilar Exclusions and Step Therapy Restrictions Among US Commercial Health Plans

BACKGROUND

Biosimilars have been introduced with the goal of competing with high-priced biologic therapies, yet their adoption has been slower than expected and resulted in limited efficiency gains. We aimed to explore factors associated with biosimilar coverage relative to their reference products by commercial plans in the United States (US).

METHODS AND DATA

We identified 1181 coverage decisions for 19 commercially available biosimilars, corresponding to 7 reference products and 28 indications from the Tufts Medical Center Specialty Drug Evidence and Coverage database. We also drew on the Tufts Medical Center Cost-Effectiveness Analysis Registry for cost-effectiveness evidence, and the Merative™ Micromedex^® RED BOOK^® for list prices. We summarized the coverage restrictiveness as a binary variable based on whether the product is covered by the health plan, and if covered, the difference of payers' line of therapy between the biosimilar and its reference product. We used a multivariate logistic regression to examine the association between coverage restrictiveness and a number of potential drivers of coverage.

RESULTS

Compared with reference products, health plans imposed coverage exclusions or step therapy restrictions on biosimilars in 229 (19.4%) decisions. Plans were more likely to restrict biosimilar coverage for the pediatric population (odds ratio [OR] 11.558, 95% confidence interval [CI] 3.906-34.203), in diseases with US prevalence higher than 1,000,000 (OR 2.067, 95% CI 1.060-4.029), and if the plan did not contract with one of the three major pharmacy benefit managers (OR 1.683, 95% CI 1.129-2.507). Compared with the reference product, plans were less likely to impose restrictions on the biosimilar-indication pairs if the biosimilar was indicated for cancer treatments (OR 0.019, 95% CI 0.008-0.041), if the product was the first biosimilar (OR 0.225, 95% CI 0.118-0.429), if the biosimilar had two competitors (reference product included; OR 0.060, 95% CI 0.006-0.586), if the biosimilar could generate annual list price savings of more than $15,000 per patient (OR 0.171, 95% CI 0.057-0.514), if the biosimilar's reference product was restricted by the plan (OR 0.065, 95% CI 0.038-0.109), or if a cost-effectiveness measure was not available (OR 0.066, 95% CI 0.023-0.186).

CONCLUSION

Our study offered novel insights on the factors associated with biosimilar coverage by commercial health plans in the US relative to their reference products. Cancer treatment, pediatric population, and coverage restriction of the reference products are some of the most significant factors that are associated with biosimilar coverage decisions.

The process defines the product: what really matters in biosimilar design and production?

Biologic drugs are highly complex molecules produced by living cells through a multistep manufacturing process. The key characteristics of these molecules, known as critical quality attributes (CQAs), can vary based on post-translational modifications that occur in the cellular environment or during the manufacturing process. The extent of the variation in each of the CQAs must be characterized for the originator molecule and systematically matched as closely as possible by the biosimilar developer to ensure bio-similarity. The close matching of the originator fingerprint is the foundation of the biosimilarity exercise, as the analytical tools designed to measure differences at the molecular level are far more sensitive and specific than tools available to physicians during clinical trials. Biosimilar development, therefore, has a greater focus on preclinical attributes compared with the development of an original biological agent. As changes in CQAs can occur at different stages of the manufacturing process, even small modifications to the process can alter biosimilar attributes beyond the point of similarity and impact clinical effectiveness and safety. The manufacturer's ability to provide consistent production and quality control will greatly influence the acceptance of biosimilars. To this end, preventing drift from the required specifications over time and avoiding the various implications brought by product shortage will enhance biosimilar integration into daily practice. As most prescribers are not familiar with this new drug development paradigm, educational programmes will be needed so that prescribers see biosimilars as fully equivalent, efficacious and safe medicines when compared with originator products.

Biologicals and biosimilars: safety issues in Europe

INTRODUCTION

Medicinal products of a biological origin are approved by the EMA at a centralized level. However, there is no harmonization about their use in Europe. The current regulation referring to the safety of biological medicinal products and biosimilars in Europe has been identified. The safety associated with medicinal products of a biological origin is assured by the pharmacovigilance system, which has evolved, but doesn't yet incorporate all of the specific information from this market segment, namely that related to the identification of drugs, and its use - including the prescription and dispensing, given the possibility of interchangeability and substitution. The terminology, information systems and traceability systems aren't entirely appropriate to ensure the safety requirements for therapy with medicinal products of a biological origin. Areas covered: This article aims to identify the prescription and dispensing profiles of reference biological medicines and biosimilars in the EU, and the determinants that support their safe use. Expert opinion: The European pharmacovigilance system must evolve to ensure the safety along all of the biologicals' therapeutic cycle. It must consider the safety for each of the medicines in addition to their safety pattern related to the eventual switching procedure.

Improving Access to Cancer Treatments: The Role of Biosimilars

Biologics play a key role in cancer treatment and are principal components of many therapeutic regimens. However, they require complex manufacturing processes, resulting in high cost and occasional shortages in supply. The cost of biologics limits accessibility of cancer treatment for many patients. Effective and affordable cancer therapies are needed globally, more so in developing countries, where health care resources can be limited. Biosimilars, which have biologic activity comparable to their corresponding reference drugs and are often more cost effective, have the potential to enhance treatment accessibility for patients and provide alternatives for decision makers (ie, prescribers, regulators, payers, policymakers, and drug developers). Impending patent expirations of several oncology biologics have opened up a vista for the development of corresponding biosimilars. Several countries have implemented abbreviated pathways for approval of biosimilars; however, challenges to their effective use persist. Some of these include designing appropriate clinical trials for assessing biosimilarity, extrapolation of indications, immunogenicity, interchangeability with the reference drug, lack of awareness and possibly acceptance among health care providers, and potential political barriers. In this review, we discuss the potential role and impact of biosimilars in oncology and the challenges related to their adoption and use. We also review the safety and efficacy of some of the widely used biosimilars in oncology and other therapeutic areas (eg, bevacizumab, darbepoetin, filgrastim, rituximab, and trastuzumab).

Overcoming Barriers to the Market Access of Biosimilars in the European Union: The Case of Biosimilar Monoclonal Antibodies

BACKGROUND

In 2014, six of the top ten blockbuster medicines were monoclonal antibodies. This multibillion-dollar market with expiring patents is the main driver for the development of biosimilar mAbs. With the ever-increasing cost of healthcare and the economic pressure to reduce or sustain healthcare expenses, biosimilars could be instrumental in reducing costs for medication and increasing patient access to treatment.

OBJECTIVES

The aim of this study is to identify and describe the barriers to market access of biosimilar mAbs in the European Union and to analyze how these barriers could be overcome.

METHODS

A narrative literature review was carried out using the databases PubMed, Embase, and EconLit. Studies were published in English or Dutch. Additionally, the reference list of the articles was checked for relevant studies. Articles and conference papers known to the authors were included as well. Articles were also identified by searching on the website of the Generics and Biosimilars Initiative (GaBI) journal.

RESULTS

Six barriers were identified based on available literature: The manufacturing process, the regulatory process, intellectual property rights, lack of incentive, the impossibility of substitution, and the innovator's reach. These six barriers are presented as a possible framework to study the market access of biosimilar mAbs. Based on the literature search, recommendations can be made to overcome these barriers: (i) invest initially in advanced production processes with the help of single-use technology, experience or outsourcing (ii) gain experience with the regulatory process and establish alignment between stakeholders (iii) limit patent litigation, eliminate evergreening benefits, build out further the unitary patent and unified patent litigation system within the EU (iv) create demand-side policies, disseminate objective information (v) change attitude toward biosimilar switching/substitution, starting with physician, and patient education (vi) differentiate the biosimilar by service offerings, use an appropriate comparator in cost-effectiveness analyses.

CONCLUSIONS

Barriers to the market access of biosimilar mAbs could be reduced when more transparency and communication/education is used in all steps toward market access in order to increase the trust in biosimilar mAbs by all stakeholders. Only then biosimilar mAbs will be able to fully capture their cost saving potential.

Biosimilars: Hope and concern

As patents of the first introduced biologic therapeutics in oncology have begun to expire, competing pharmaceutical companies are allowed to produce and market the same protein as the original agent. These products are called biosimilars. Upon patent expiration, biosimilars would hopefully be a cheaper alternative to the original agent and that is the main reason for their existence. Although the financial aspect is similar to generics, the complex nature of these products generates the need for a distinct regulatory environment. Biosimilars are produced by DNA technology in bacteria, plant cells, or animal cells, while generics are produced by chemical synthesis. Details in the process of synthesis, selection of the microorganism, protein extraction, purification and manufacturing, affect the precise nature of the end product. Monoclonal antibodies are large proteins with four polypeptide chains and interact variably with each other and with the environment. It is important for payors to realize that biosimilars are different from generics; therefore, they need to develop different set of rules for approving, registering, and dispensing biosimilars. Regulators ought to respect the physicians’ request for non-interchangeability and facilitate in any possible way of traceability. Such regulations along with a rigorous pharmacovigilance program will satisfy the concerns for true equivalence in activity and long-term safety. This is the only way to accumulate over time reliable safety information for new biosimilars. In conclusion, the wish born by the medical community and the society for a more affordable health system triggers the emergence of biosimilars, which could meet that goal if properly regulated.

Key considerations in the preclinical development of biosimilars

Biosimilar development requires several steps: selection of an appropriate reference biologic, understanding the key molecular attributes of that reference biologic and development of a manufacturing process to match these attributes of the reference biologic product. The European Medicines Agency (EMA) and the FDA guidance documents state that, in lieu of conducting extensive preclinical and clinical studies typically required for approval of novel biologics, biosimilars must undergo a rigorous similarity evaluation. The aim of this article is to increase understanding of the preclinical development and evaluation process for biosimilars, as required by the regulatory agencies, that precedes the clinical testing of biosimilars in humans.

Biosimilars in oncology: from development to clinical practice

Biologics play an integral role in the treatment of cancer not only for their therapeutic effects and ability to improve outcomes, but also as supportive care agents. Biologics are more complex to manufacture and take longer to bring to market. Because biologics are considerably more costly than small-molecule drugs, their use has placed an increasing economic demand on healthcare systems worldwide. Biosimilars are designed to be highly similar to existing branded biologics, but because biologics cannot be exactly copied, biosimilars should not be referred to as generic, exact versions of the innovator biologic. Biosimilars have the potential to increase access and provide lower cost options for cancer care as patent protection for some of the most widely used biologics begins to expire. Regulatory requirements for biosimilars are evolving, as are global harmonization and/or standardization strategies that can facilitate their robust clinical development. This review highlights critical factors involved with the integration of biosimilars into oncology treatment paradigms and practices. Clinicians will likely seek out practice guidelines and position statements from established scientific societies to help evaluate key information regarding biosimilars, such as efficacy, safety, comparability, and interchangeability with the reference biologic. Automatic substitution, nomenclature, extrapolation of clinical data from one indication to another, as well as parameters for ongoing pharmacovigilance are evolving considerations. Education of physicians and other healthcare providers, payers, and patients about biosimilars may facilitate informed decision making, promote acceptance of biosimilars into clinical practice, increase accessibility, and expedite associated health and economic benefits.

Developing oncology biosimilars: an essential approach for the future

The treatment of many diseases, particularly cancer, has been profoundly impacted by the introduction of biologic therapies (biologics), which are incorporated into the treatment algorithms of most oncology clinical practice guidelines. Biologics are large molecular weight, structurally complex proteins that are produced via complex manufacturing processes. With the patents of key biologics, including many widely used in oncology, set to expire in the near future, a number of pharmaceutical companies have focused on developing biosimilars. While the goal of development is to demonstrate that the biosimilar product is highly similar to the reference biologic product, biosimilars should not be viewed as "generic" biologics. Generic drugs are small chemical moieties that are identical to the patent-expired "reference" small-molecule drugs. It is not possible to produce an identical copy of a biologic, so the term "biosimilar" was chosen to define an appropriately similar biologic product. Improving patient access to cancer therapies such as biologics and reducing healthcare costs are key initiatives of the US Government; the integration of approved biosimilars into clinical practice will be instrumental in accomplishing these goals.