Biosimilars also known as follow-on biologics are biologic medical products
whose active drug substance is made by a living organism or derived
from a living organism by means of recombinant DNA or controlled gene
expression methods.
Biosimilars or follow-on biologics are terms used to describe officially approved subsequent versions of innovator biopharmaceutical products made by a different sponsor following patent and exclusivity expiry on the innovator product.Biosimilars are also referred to as subsequent entry biologics (SEBs) in Canada.Reference to the innovator product is an integral component of the approval.
Unlike the more common small-molecule drugs, biologics generally exhibit high molecular complexity, and may be quite sensitive to changes in manufacturing processes. Follow-on manufacturers do not have access to the originator's molecular clone and original cell bank, nor to the exact fermentation and purification process, nor to the active drug substance. They do have access to the commercialized innovator product. Differences in impurities and/or breakdown products can have serious health implications. This has created a concern that copies of biologics might perform differently than the original branded version of the product. Consequently only a few subsequent versions of biologics have been authorized in the US through the simplified procedures allowed for small molecule generics, namely Menotropins (January 1997) and Enoxaparin (July 2010), and a further eight biologics through the 505(b)(2) pathway.
The FDA gained the authority to approve biosimilars (including interchangeables that are substitutable with their reference product) as part of the Patient Protection and Affordable Care Act signed by President Obama on March 23, 2010 - none have yet been approved. The FDA has previously approved biologic products using comparability, for example, Omnitrope in May 2006, but this like Enoxaparin was also to a reference product, Genotropin, originally approved as a biologic drug under the FD&C Act ) .
Recombinant therapeutic proteins are of a complex nature (composed of a long chain of amino acids, modified amino acids, derivatized by sugar moieties, folded by complex mechanisms). These proteins are made in living cells (bacteria, yeast, animal or human cell lines). The ultimate characteristics of a drug containing a recombinant therapeutic protein are to a large part determined by the process through which they are produced: choice of the cell type, development of the genetically modified cell for production, production process, purification process, formulation of the therapeutic protein into a drug.
After the expiry of the patent of approved recombinant drugs (e.g. insulin, human growth hormone, interferons, erythropoietin, and more) any other biotech company can "copy" and market these biologics (thus called biosimilars).
However, because no two cell lines, developed independently, can be considered identical, biotech medicines cannot be fully copied. The European Medicines Agency, EMEA, has recognized this fact, which has resulted in the establishment of the term "biosimilar" in recognition that, whilst biosimilar products are similar to the original product, they are not exactly the same. Small distinctions in the cell line, in the manufacturing process or in the surrounding environment can make a major difference in side effects observed during treatment, i.e. two similar biologics can trigger very different immunogenic response. Therefore, and unlike chemical pharmaceuticals, substitution between biologics, including biosimilars, can have clinical consequences and does create putative health concerns.
Biosimilars are subject to an approval process which requires substantial additional data to that required for chemical generics, although not as comprehensive as for the original biotech medicine. However, the safe application of biologics is also dependent on an informed and appropriate use by healthcare professionals and patients. Introduction of biosimilars also requires a specifically designed pharmacovigilance plan. It is difficult and costly to recreate biologics because the complex proteins are derived from living organisms that are genetically modified. In contrast, small molecule drugs made up of a chemically based compound can be easily replicated and are considerably less expensive to reproduce. In order to be released to the public, biosimilars must be shown to be as close to identical to the parent biological product based on data compiled through clinical, animal and analytical studies. The results must demonstrate that they produce the same clinical results and are interchangeable with the referenced FDA licensed biological product already on the market. As of December 2009, ambiguities concerning naming, regional differences in prescribing practices, and regional differences in legally-defined rules with respect to substitution are important points that still need to be resolved to ensure a safe use of biosimilars.
Biosimilars or follow-on biologics are terms used to describe officially approved subsequent versions of innovator biopharmaceutical products made by a different sponsor following patent and exclusivity expiry on the innovator product.Biosimilars are also referred to as subsequent entry biologics (SEBs) in Canada.Reference to the innovator product is an integral component of the approval.
Unlike the more common small-molecule drugs, biologics generally exhibit high molecular complexity, and may be quite sensitive to changes in manufacturing processes. Follow-on manufacturers do not have access to the originator's molecular clone and original cell bank, nor to the exact fermentation and purification process, nor to the active drug substance. They do have access to the commercialized innovator product. Differences in impurities and/or breakdown products can have serious health implications. This has created a concern that copies of biologics might perform differently than the original branded version of the product. Consequently only a few subsequent versions of biologics have been authorized in the US through the simplified procedures allowed for small molecule generics, namely Menotropins (January 1997) and Enoxaparin (July 2010), and a further eight biologics through the 505(b)(2) pathway.
Approval processes
The European regulatory authorities led with a specially adapted approval procedure to authorize subsequent versions of previously approved biologics, termed "similar biological medicinal products" - often called biosimilars for short. This procedure is based on a thorough demonstration of "comparability" of the "similar" product to an existing approved product.In the US the Food and Drug Administration (FDA) held that new legislation was required to enable them to approve biosimilars to those biologics originally approved through the PHS Act pathway. Additional Congressional hearings have been held,. On March 17, 2009, the Pathway for Biosimilars Act was introduced in the House. See the Library of Congress website and search H.R. 1548 in 111th Congress Session. Since 2004 the FDA has held a series of public meetings on biosimilars.The FDA gained the authority to approve biosimilars (including interchangeables that are substitutable with their reference product) as part of the Patient Protection and Affordable Care Act signed by President Obama on March 23, 2010 - none have yet been approved. The FDA has previously approved biologic products using comparability, for example, Omnitrope in May 2006, but this like Enoxaparin was also to a reference product, Genotropin, originally approved as a biologic drug under the FD&C Act ) .
Background
Cloning of human genetic material and development of in vitro biological production systems has allowed the production of virtually any recombinant DNA based biological substance for eventual development of a drug. Monoclonal antibody technology combined with recombinant DNA technology has paved the way for tailor-made and targeted medicines. Gene- and cell-based therapies are emerging as new approaches.Recombinant therapeutic proteins are of a complex nature (composed of a long chain of amino acids, modified amino acids, derivatized by sugar moieties, folded by complex mechanisms). These proteins are made in living cells (bacteria, yeast, animal or human cell lines). The ultimate characteristics of a drug containing a recombinant therapeutic protein are to a large part determined by the process through which they are produced: choice of the cell type, development of the genetically modified cell for production, production process, purification process, formulation of the therapeutic protein into a drug.
After the expiry of the patent of approved recombinant drugs (e.g. insulin, human growth hormone, interferons, erythropoietin, and more) any other biotech company can "copy" and market these biologics (thus called biosimilars).
However, because no two cell lines, developed independently, can be considered identical, biotech medicines cannot be fully copied. The European Medicines Agency, EMEA, has recognized this fact, which has resulted in the establishment of the term "biosimilar" in recognition that, whilst biosimilar products are similar to the original product, they are not exactly the same. Small distinctions in the cell line, in the manufacturing process or in the surrounding environment can make a major difference in side effects observed during treatment, i.e. two similar biologics can trigger very different immunogenic response. Therefore, and unlike chemical pharmaceuticals, substitution between biologics, including biosimilars, can have clinical consequences and does create putative health concerns.
Biosimilars are subject to an approval process which requires substantial additional data to that required for chemical generics, although not as comprehensive as for the original biotech medicine. However, the safe application of biologics is also dependent on an informed and appropriate use by healthcare professionals and patients. Introduction of biosimilars also requires a specifically designed pharmacovigilance plan. It is difficult and costly to recreate biologics because the complex proteins are derived from living organisms that are genetically modified. In contrast, small molecule drugs made up of a chemically based compound can be easily replicated and are considerably less expensive to reproduce. In order to be released to the public, biosimilars must be shown to be as close to identical to the parent biological product based on data compiled through clinical, animal and analytical studies. The results must demonstrate that they produce the same clinical results and are interchangeable with the referenced FDA licensed biological product already on the market. As of December 2009, ambiguities concerning naming, regional differences in prescribing practices, and regional differences in legally-defined rules with respect to substitution are important points that still need to be resolved to ensure a safe use of biosimilars.