Case: Amgen Canada Inc v Canada (Minister of Health), 2015 FC 1261 (Court File No. T-2072-12)
Drug: NEUPOGEN® (filgrastim)
Nature of case: Prohibition application pursuant to section 6 of the Patented Medicines (Notice of Compliance) Regulations, SOR/93-133 (the Regulations)
Successful party: Apotex Inc.
Date of decision: November 10, 2015
Amgen Canada Inc. and Amgen Inc. (collectively, Amgen) markets and sells filgrastim in Canada under the name NEUPOGEN® for use in the treatment of neutropenia. NEUPOGEN® is a recombinant version of Granulocyte Colony Stimulating Factor (G-CSF), a human protein. Apotex Inc. (Apotex) has sought approval for a subsequent-entry biologic (or biosimilar) of filgrastim for the same treatment indication.
The Federal Court dismissed Amgen’s application for an order prohibiting the Minister of Health from issuing a Notice of Compliance (NOC) for Apotex’s biosimilar, and held that Amgen had failed to show that Apotex’s obviousness allegation regarding its patent was not justified.
Canadian Patent No. 1,341,537 (537 Patent) is listed on the patent register in respect of NEUPOGEN®. The 537 Patent was filed on August 25, 1986, issued on July 31, 2007, and will expire on July 31, 2024.
Claim 43 of the 537 Patent covers a recombinant G-CSF polypeptide having a specific sequence of 175 amino acids. Justice Hughes construed this claim to mean a polypeptide with an amino acid sequence beginning with a Met (methionine), and the remainder of the sequence having some or all of the sequence and some or all of the biological properties of the natural G-CSF. Claim 43 was the only claim at issue in this proceeding.
The isolation, purification and biological activity of the naturally-occurring G-CSF had been previously reported in a prior art publication authored by Dr. Carl Welte (“Welte Publication”). The Welte Publication is referenced in the 537 Patent.
The Claim for Recombinant G-CSF was Novel
Amgen argued that the recombinant G-CSF was not disclosed in the Welte Publication since it differed from the naturally-occurring G-CSF. The recombinant G-CSF begins with a Met residue, which the naturally-occurring protein does not. Further, the Welte Publication did not disclose the amino acid sequence of the naturally-occurring G-CSF. Justice Hughes accepted Amgen’s argument, and held that the Welte Publication did not anticipate claim 43 of the 537 Patent.
The Claim for Recombinant G-CSF was Obvious
Amgen argued that making a recombinant form of G-CSF, and in particular, developing a process for making the recombinant protein on a large scale, involved a high degree of inventive skill. Justice Hughes rejected this argument and held that the steps involved in making a recombinant protein “were routine in the sense that they were carried out by skilled persons operating with the science as it was known at the time.” Further, the skilled person would have been motivated by the Welte Publication to make it.
On this basis, Justice Hughes held that Amgen had failed to show that Apotex’s obviousness allegation regarding claim 43 was not justified. The Court acknowledged that the process that Amgen developed to make the recombinant protein on a large scale may be patentable, but found that this process was not within the scope of claim 43.
The Promised Utility of Claim 43 had been Demonstrated
Amgen argued that the promised utility of claim 43 was a recombinant protein having some or all of the amino acid structure of the naturally-occurring G-CSF and some or all of its biological properties. Justice Hughes accepted this argument and held that the promised utility of claim 43 had been demonstrated at the Canadian filing date. Amgen had made the recombinant G-CSF and demonstrated that it shared at least some of the physical structure and biological properties of the naturally-occurring protein.
24-month Statutory Stay Extended
The 24-month statutory stay under the Regulations was due to expire on November 16, 2014, but on October 7, 2013, the Court extended the stay and ordered that a judgment must issue no later than 60 days following the hearing. The reasons for judgment do not indicate the basis on which the extension was granted.
Amgen has sought an expedited appeal of the Court’s judgment (Court File No. A-501-15).