Biosimilars: Review of current applications,obstacles, and their future in medicine

Biosimilars are a growing drug class designed to be used interchangeably with biologics. Biologics are created in living cells and are typically large, complex proteins that may have a variety of uses. Within the field of gastroenterology alone, biologics are used to treat inflammatory bowel diseases, cancers, and endocrine disorders. While biologics have proven to be effective in treating or managing many diseases, patient access is often limited by high costs. The development of biosimilars is an attempt to reduce treatment costs. Biosimilars must be nearly identical to their reference biologics in terms of efficacy, side effect risk profile, and immunogenicity. Although the manufacturing process still involves production within living cells, biosimilars undergo fewer clinical trials than do their reference biologics. This ultimately reduces the cost of production and the cost of the biosimilar drug compared to its reference biologic. Currently, seven biosimilars have been approved by the United States Food and Drug Administration (FDA) for use in Crohn’s disease, ulcerative colitis, and colorectal cancer. There are other biologics involved in treating gastroenterologic diseases for which there are no FDA approved biosimilars. Although biosimilars have the potential to reduce healthcare costs in chronic disease management, they face challenges in establishing a significant market share. Physician comfort in prescribing reference biologics instead of biosimilars and patient reluctance to switch from a biologic to a biosimilar are two common contributing factors to biosimilars’ slow increase in use. More time will be needed for biosimilars to establish a larger and more consistent market share compared to their reference biologics. Additional data confirming the safety and efficacy of biosimilars, increased number of available biosimilars, and further cost reduction of biosimilars will all be necessary to improve physician confidence in biosimilars and patient comfort with biosimilars.     

Systemic rheumatic diseases: From biological agents to small molecules

The development of biologics and small oral molecules has recently changed the scenario of pharmacologic treatment of systemic rheumatic diseases and it has become a real revolution. These drugs have innovative mechanisms of action, based on the inhibition of specific molecular or cellular targets directly involved in disease pathogenesis.This new scenario has lead to a regular update of the management recommendations of several institutions, such as those for Rheumatoid Arthritis treatment that address the use of conventional and biologic therapies including TNF inhibitors (adalimumab, certolizumab pegol, etanercept, golimumab, infliximab), abatacept, rituximab, IL-6 inhibitors (tocilizumab and sarilumab), biosimilars and small oral molecules (the JAK inhibitors tofacitinib and baricitinib). Monotherapy, combination therapy, treatment strategies (such as treat-to-target) and the targets of sustained clinical remission or low disease activity are the final goal of the guidelines for rheumatic patients management. In another condition represented by Axial Spondyloarthritis guidelines suggest to start first with non-steroidal anti-inflammatory drugs to improve lifestyle and reduce spine inflammation, but if this is not achieved in 2–4 weeks it is important to consider the use of local therapies (i.e. glucocorticoid injections) or to start biologic therapy such as TNF inhibitors and then eventually switching to another TNF inhibitor or swapping to IL-17 inhibitor. In the case of active Psoriatic Arthritis, guidelines suggest to start with non-steroidal anti-inflammatory drugs and even local glucocorticoid injections especially for oligoarthritis, then to start conventional therapies if lack of efficacy, and finally start biologics or small oral molecules in the presence of drugs toxicity, unfavorable prognostic factors and still active arthritis. In several cases, active Psoriatic Arthritis patients develop a complex clinical condition with comorbidities such as diabetes, inflammatory bowel disease and high risk of infections, and for this reason the American College of Rheumatology and the National Psoriasis Foundation have developed specific guidelines for their management.Biologic and new small molecules therapies are very expensive, but the availability of biosimilars offers the opportunity of reducing the treatment cost and significantly decreasing the cost of originators as well. In fact, we live in a period characterized by the need to rationalize costs of these drugs, to allow treating a higher number of patients and to maintain a homogeneous possibility of treatment choice. For these reasons, we need to follow scientific guidelines and patients' clinical conditions to choose the correct treatment, also based on the economic burden of therapies.     

The First 2 Years of Biosimilar Epoetin for Cancer and Chemotherapy‐Induced Anemia in the U.S.: A Review from the Southern Network on Adverse Reactions

Biosimilars are biologic drug products that are highly similar to reference products in analytic features, pharmacokinetics and pharmacodynamics, immunogenicity, safety, and efficacy. Biosimilar epoetin received Food and Drug Administration (FDA) approval in 2018. The manufacturer received an FDA nonapproval letter in 2017, despite receiving a favorable review by FDA''s Oncologic Drugs Advisory Committee (ODAC) and an FDA nonapproval letter in 2015 for an earlier formulation. We discuss the 2018 FDA approval, the 2017 FDA ODAC Committee review, and the FDA complete response letters in 2015 and 2017; review concepts of litigation, naming, labeling, substitution, interchangeability, and pharmacovigilance; review European and U.S. oncology experiences with biosimilar epoetin; and review the safety of erythropoiesis‐stimulating agents. In 2020, policy statements from AETNA, United Health Care, and Humana indicated that new epoetin oncology starts must be for biosimilar epoetin unless medical need for other epoetins is documented. Empirical studies report that as of 2012, reference epoetin use decreased from 40%–60% of all patients with cancer with chemotherapy‐induced anemia to <5% of such patients because of safety concerns. Between 2018 and 2020, biosimilar epoetin use varied, increasing to 81% among one private insurer''s patients covered by Medicare whose cancer care is administered with Oncology Analytics and to 41% with the same private insurer''s patients with cancer covered by commercial health insurance and administered by the private insurer, to 0% in several Veterans Administration Hospitals, increasing to 100% in one large county hospital in California, and with yet‐to‐be‐reported data from most oncology settings. We conclude that biosimilar epoetin appears to have overcome some barriers since 2015, although current uptake in the U.S. is variable. Pricing and safety considerations for all erythropoiesis‐stimulating agents are primary determinants of biosimilar epoetin oncology uptake.Implications for PracticeFew oncologists understand substitution and interchangeability of biosimilars with reference drugs. Epoetin biosimilar is new to the market, and physician and patient understanding is limited. The development of epoetin biosimilar is not familiar to oncologists.     

Switching to biosimilars in the treatment of rheumatic diseases

Introduction: For successful switching of bio-originators to biosimilars, confidence in the switch is an important criterion. To promote confidence, scientific evidence is critical, but still there are insufficient data for the majority of approved biosimilars.

Areas covered: Scientific evidence for switching from bio-originator DMARDs to biosimilars is derived from randomized controlled trials (RCTs) for switching, extension studies of RCTs for the approval process, and real-world observational studies. To identify candidate studies, PubMed was searched to collect appropriate studies in all approved biosimilars for the treatment of rheumatic diseases. In addition, abstracts for scientific meetings were reviewed to discover abstracts focused on switching. To date, we have identified 17 extension studies of RCTs, 1 RCT, and 17 real-world observational studies. Most real-world studies have originated from CT-P13 and SB4. Switching was definitively safe and effective in most of studies, but some nocebo effects were observed.

Expert commentary: Clear guidelines for switching and data from post-marketing surveillance and registries will be required to confirm existing results on the safety and efficacy of switching from bio-originators to biosimilars. To lessen the nocebo effect against biosimilars, effective educational programs should be provided for all stakeholders, including patients and physicians.     

Through the looking glass: the protein science of biosimilars

Biopharmaceuticals have revolutionized the treatment and management of many diseases. The advent of recombinant erythropoietins has greatly benefited patients with anemia related to chronic kidney disease and cancer, virtually eliminating the need for blood transfusions. Currently, the patents for many biopharmaceutical molecules have expired or are approaching expiration and a number of biosimilars manufacturers are aiming to claim part of the market share. Unlike the situation for synthetic “small molecule” drugs, identical copies of far more complex biopharmaceuticals cannot be produced. A biopharmaceutical can be 100 to 1000 times larger than a synthetic chemical drug, with extremely complex three-dimensional structure and biological functions which are often not completely understood. Due to their nature and complexity, these fascinating therapeutic molecules are products of highly controlled biological processes. This review takes a look at how biosimilars are fundamentally different from their originator products by examining the biopharmaceutical production process and how it can influence the structure and function of the final drug product.