Intellectual Property
By: Micheline Gravelle, M.Sc. and Sie Lung Tjew, M.Sc.
Patenting Antibodies
in Canada Antibodies represent a significant slice of the biotechnology market. Global sales of monoclonal antibodies – for use as therapeutics, diagnostics or as reagents in research – totaled approximately $35 billion in 2008 and grew to $55 billion in 2010, wherein the top 5 brands had sales of over $5 billion each.
T
his remarkable growth is likely to continue given the increasing number of antibodies receiving market authorization by the various regulatory agencies. For example, the U.S. Food and Drug Administration approved4 new therapeutic monoclonal antibodies in 2009, while the European Medicines Agency approved a record-setting7. Even more telling is that over 200 antibodies were working their way through the various stages of a clinical trial in the United States in 2008. This upcoming flood of antibody products is likely to push global revenues to new heights. Manufacturers of innovative antibody products, like other segments of the pharmaceutical industry, must constantly guard against infringing products. Given the financial stakes involved, it is imperative that innovators protect their intellectual property as much as possible, for as long as possible, in order to realize the maximum return on their investment. Weakened patent portfolios from a lack of timely and sustained capital has been cited as one of the barriers to
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successful commercialization of biotechnology in Canada. A poignant reminder of the value of a properly drafted patent comes from a recent case in the U.S. In Centocor Ortho Biotech, Inc. v. Abbott Labs a jury award of $1.67 billion for patent infringement was overturned by a panel of the Federal Circuit when it found the antibody claims to be invalid. A patent fences off the invention so that others know where they may not trespass. The invention is defined by the claims which essentially gives the inventor or patent owner the right to exclude others from making, using or selling the invention for a limited period of time – which for most countries is 20 years from the filing date. The claims must be considered novel, inventive and useful over what has been disclosed in the prior art. The claims must also be sufficiently supported by the disclosure provided in the patent application upon filing. The disclosure must also fully and correctly describe the invention such that it would enable one of skill in the art to make and use the invention as claimed. In the recent decision of Re Immunex Corporation Patent Application No. 583,988 (hereinafter, “Immunex”), the Patent Appeal
Board (PAB), in seeking consistency with other common-law jurisdictions, adopted the principles established in U.S. and U.K. courts that an applicant may claim monoclonal antibodies immunoreactive with a specific antigen without an antibody having actually been prepared, provided that the antigen is a novel polypeptide that has been well-defined, for example, by its structure, formula, chemical name, or physical properties, or by depositing the protein in a public depository. Immunex’s patent application was filed on November 24, 1988, with claims directed to monoclonal antibodies immunoreactive with IL-1R polypeptides, as well as antibodies claimed in a product-by-process format. The antibody claims were originally rejected by the patent examiner because such an antibody had not been produced by the filing date. The main issue was whether these claims were sufficiently supported by the description. In addressing this issue, the PAB considered whether the claims were enabled, adequately described and had utility.
Enablement Methods for producing polyclonal antibodies have long been recognized by the Canadian Intellectual Property Office (CIPO) as sufficiently well-established such that they do not
