“Seeing a pathway for biological generics is one of my highest priorities this year,” US Congressman Henry Waxman said via a video link to the World Generics Medicines Congress Europe 2009, held in London, UK, in February.
On 17 March 2009, US Congresswoman Anna Eshoo (Democrat of California, USA) introduced a second biosimilars bill in the House that will compete with the bill introduced a week ago by US Congressman Henry Waxman, Chairman of the House Energy and Commerce Committee. Both bills would create the first US approval pathway for follow-on biologics. The bills differ in areas such as length of exclusivity for innovators and the need for guidance documents.
Physicians should become aware of potential differences between biopharmaceuticals (biologicals) and their generic versions (called biosimilars in the EU and follow-on protein products in the US) that will soon enter the market, and that the impact on safety and efficacy is critical for patient safety. “Healthcare professionals need to understand the critical issues surrounding the use of biosimilars to make informed treatment decisions”, states Professor Huub Schellekens in Biosimilar therapeutics – what do we need to consider in NDT Plus. 2009;2(Suppl 1):i27-i36.
The primary safety concern for biosimilar agents is their potential immunogenicity. Using biopharmaceuticals to replace endogenous proteins that may be present at insufficient concentrations carries the serious risk of stimulating the immune system to develop anti-product antibodies (Abs), which may cross-react with endogenous protein.
On 11 March 2009, Henry Waxman, Frank Pallone, Nathan Deal, and Jo Ann Emerson, all members of the US House Committee on Energy and Commerce, introduced the Promoting Innovation and Access to Life-Saving Medicine Act (bipartisan bill HR 1427), to allow the US FDA to approve affordable ‘biosimilar’ copies of biotech drugs or ‘biologicals’.
Genentech has put a clear position on biosimilars on its website. The company explains that the terms ‘biosimilar’ or ‘follow-on biologic’ refer to products that are marketed after expiration of patents, which are claimed to have similar properties to existing biological products. Due to the complexity of biologicals, a product can only be made that is similar, but not identical.
Just like generic medicines, biosimilars could substantially reduce healthcare costs. Yet it seems that among physicians, pharmacists and patients there exists resistance against these cheaper versions of biotechnological medicines.
Biosimilars or follow-on biologics (FOBs) are biopharmaceuticals that, unlike small molecule generic products, are copies of larger, much more complex proteins. As such, data generated from one biopharmaceutical cannot be extrapolated to another. Unlike small molecule generics, FOBs require a full developmental programme, albeit smaller than for an originator product. This has been recognized by European regulatory authorities and it is becoming clear that accelerated processes for FOB marketing approval are not feasible.
The first generation biopharmaceuticals are copies of endogenous human proteins, such as erythropoietin, insulin, growth hormones and cytokines, developed using recombinant DNA technology or hybridoma techniques. These compounds have revolutionised the treatment of many diseases, including anaemia, cancer, diabetes, hepatitis and multiple sclerosis. With expiring patents the market opens to biosimilar versions of these products.
Analytical studies have revealed the extent of heterogeneity of biopharmaceuticals produced by different manufacturing processes around the world. Key differences have been found in the structure, stability, composition, concentration and activity of manufactured erythropoietins (epoetins or EPOs).