Health Canada's move comes as the expiry of patents protecting some of the more established biologic agents begins to loom on the regulatory horizon, increasing the likelihood that such products will become the target of copycat competition. Government drug agencies worldwide are working to establish regulatory frameworks to cover SEBs, which as Health Canada's guidance points out, are not simply "generic biologics," but unique, complex biological agents that have similarity to previously approved medications. At present, US legislators are discussing the "Pathway for Biosimilars Act," while the EMEA recognised the "uniqueness" of a biosimilar agent in an updated set of guidelines that it issued July last year. Subsequently, the EMEA has approved several such products including versions of Johnson & Johnson's erythropoesis stimulating agent Eprex and, last month, several competitors for Amgen's neutropenia treatment Neupogen, under its biosimilars legislation. Under Health Canada's SEB proposals sponsors seeking clearance for biosimilars, on patent expiry, would be permitted to incorporate publicly available safety and efficacy data in their regulatory submissions. The agency went on to say that eligibility for the SEB pathway hinges on the ability to demonstrate similarity to a suitable reference product, which excludes, for example, biologics produced in transgenic organisms rather than through in vitro cell culture as this is deemed a sufficiently unique method of manufacture to warrant a full biologics review. Health Canada also said that compounds accepted for review would not automatically be designated as substitutable for previously approved medications, adding that such designation would be decided on a case-by-case basis. In addition, interchangeability, which enables physicians to prescribe either the SEB or the reference product, would be determined separately from any approval ruling covered by the draft guidelines. Health Canada's proposals state that SEBs would not be cleared for the whole range of indications for which the reference product is approved unless data proving the efficacy in each therapeutic setting is provided. The document also stipulates that comparative pharmacokinetic and bioavailability studies be carried out to establish the similarity of the SEB and reference product, and that the resulting data should form the basis of a novel monograph for each SEB under review. The agency, which will be accepting feedback on the proposals until April 16, said that it plans to publish additional guidance covering specific product classes in the coming months. The document, titled "Information and Submission Requirements for Subsequent Entry Biologics," along with forms for submitting comments or requesting to participate in the consultation, are available at www.hc-sc.gc.ca/dhp-mps/brgtherap/activit/consultation/seb-pbu/index_e.html.