Brand name companies that have spent huge amounts of time and money pioneering these biologic drugs are keen to hold onto their exclusive markets as long as possible. Canada has a specialized litigation option available to protect certain patented drugs on the market. The process may block a second-entry drug that is referencing a patent owner’s clinical trial data.
This unique Canadian system is informally called the “NOC Regulations.”1 It requires generic and biosimilar drug companies to establish freedom-to-operate (clearance) with respect to certain patents as a precondition to market authorization. This is in sharp contrast to conventional Canadian patent enforcement litigation that typically begins only after marketing authorization is granted. In comparison, the U.S. has created its own specialized and complex biosimilar litigation process, which is beyond the scope of this article.
This article will review the NOC Regulations as well as conventional patent litigation options that apply in proceedings involving biosimilars.
Health Canada Opens the Door to Biosimilars
A biosimilar is a complex drug, such as a protein drug, that can be approved for sale on the basis that it is chemically similar to an innovator biologic drug already on the market.2 This standard for market approval is less strict than bioequivalence, which applies to conventional generic pharmaceutical drugs. For instance, showing biosimilarity allows biosimilar manufacturers to rely largely on the innovator drug’s clinical data, thereby dramatically reducing the time and expense otherwise required to obtain market authorization. Health Canada approves drugs for marketing by issuing a marketing authorization, called a Notice of Compliance (NOC). An NOC is issued when a drug manufacturer’s new drug submission (NDS) is approved. OMNITROPE (somatropin; human growth hormone) is an example of a biosimilar that has been approved in Canada by relying on clinical data for Pfizer’s innovator somatropin product.3
Also, Health Canada recently published guidance on the regulatory pathway for biosimilar approval in Canada.4 Now that the regulatory pathway has been clearly laid out, innovation companies are reviewing and attempting to improve their patent barriers, while biosimilar manufacturers are trying to find a safe pathway for freedom-to-operate with respect to patented drugs in Canada.
The Health Canada Patent Register
In connection with the NOC Regulations, Health Canada maintains its own Patent Register, independent from the Canadian Intellectual Property Office, relating to medicines and their use. The Patent Register is somewhat analogous to the U.S. Orange Book for conventional pharmaceutical litigation. However, Health Canada does not have any involvement in examining or issuing patents.
The sole purpose of the Register is to prevent patent infringement in certain circumstances. Only a company that applies for, or already has an NOC for an approved patented drug may be eligible to take advantage of this specialized process. While only certain types of patents qualify, Health Canada clearly stated that biologic patents are eligible for the Register.5 For instance, to be eligible for listing, a patent must claim either an approved:
- medicinal ingredient;
- formulation that contains the medicinal ingredient;
- dosage form; or
- use of the medicinal ingredient.
The Patent Register also has strict, non-extendable time limits. For instance, a patent can be listed at one of two times:
- A patent that is issued at the time of filing an NDS (or supplementary NDS) must be listed at the time of filing the submission; or
- A patent application that has a filing date before the filing of the NDS (or supplementary NDS), must be listed within 30 days after the issuance of the patent.
Health Canada vets all requests to list patents on the Register.
Patent Register Procedure
In order to receive marketing authorization, the biosimilar company must address freedom-to-operate with respect to patents on the Health Canada Patent Register. If there are no relevant patents on the Patent Register, then Health Canada will not have to hold up drug approval pending resolution of patent issues. The Patent Register provides significant benefits to a patent owner by keeping a competitor from entering the market. In contrast, prior to the creation of the Patent Register, the patent owner often had to use conventional patent litigation to chase a competitor for patent infringement after the medicine was already on the market. This created inefficiencies since interlocutory injunctions are difficult to obtain and it takes a long time to bring a patent infringement case to a trial. The brand name company would lose significant market share in the meantime.
The pre-emptive NOC Proceeding is a faster and cheaper way to keep a competitor off the market than a patent infringement trial. The filing of the NOC Proceeding starts an automatic 24-month stay of NOC issuance to the biosimilar company (it is, in effect, like an injunction). The NOC may only be issued when the patent expires or the biosimilar company wins the NOC Proceeding. In contrast, as mentioned above, it is typically very difficult to obtain an interlocutory injunction against a competitor in Canada in a patent infringement lawsuit. A disadvantage of filing the NOC Proceeding is in the event that the generic or biosimilar company wins, the patent owner may be liable to the competitor for costs and damages for delaying biosimilar drug entry into the market.
The NOC Regulations have been extensively litigated in the context of conventional, small molecule pharmaceuticals. Notwithstanding that an NOC Proceeding has not yet been completed for a biosimilar, the NOC Regulations will become an important patent protection tool as biosimilar development increases.
The first biosimilar NOC Proceeding involved Teva’s biosimilar version of filgrastim.6 Amgen had the first approved filgrastim product in Canada, under the brand name NEUPOGEN, which expires on July 31, 2024. Amgen started an NOC Proceeding in an attempt to block Teva’s biosimilar filgrastim. In defence, Teva had alleged that claims of the Amgen patent in issue were either invalid, infringed or not relevant. The case was settled in August 2013. Amgen still has the only approved filgrastim product in Canada as of the time of writing this article. The terms of the Canadian settlement are unknown since neither company appears to have issued a press release on its terms. It is possible that the settlement may involve Teva keeping its filgrastim product off the market for a period of time. In the U.S. patent litigation on the filgrastim product (which is completely independent from the Canadian litigation), Teva had earlier admitted in a settlement that certain Amgen U.S. patent claims were infringed, valid and enforceable, and a court injunction was issued that would keep Amgen off the market until December 2013.
Conventional Patent Infringement Lawsuit
A conventional patent infringement lawsuit may be brought by a patent owner, irrespective of whether it has engaged in an NOC Proceeding. The patent owner can commence the patent infringement lawsuit in Federal Court, even if it lost in an NOC Proceeding. Likewise, the biosimilar company may lose in the NOC Proceeding, but later establish at a trial that the patent is invalid or not infringed. Additionally, Canadian patent infringement litigation is more extensive and permits discovery and trial testimony.
In a conventional patent infringement suit, the patent owner would typically sue for patent infringement and request remedies such as damages or an accounting of profits. Accounting of profits is a remedy that is an alternative to damages, in which the plaintiff receives the defendant’s profits from the infringement. An injunction and delivery up to the patent owner of the infringing drug may also be requested. An injunction may also be requested before trial, but is unlikely to be granted because it is very difficult for a patent owner to show irreparable harm not compensable by damages, which is a precondition for the interlocutory injunction.
In infringement proceedings, the biosimilar company may challenge the validity of a patent, for example, that the patent claims lack novelty, inventiveness or support. A patent is presumed valid during litigation and the onus is on the challenger to invalidate a patent. Also, while evidence used to attack validity of a patent in another country may be useful in Canada, each country has different laws and standards on patent validity issues.
It would typically take at least a couple of years (often much longer) before a trial decision.
Patent owners and biosimilar manufacturers need to be prepared to engage the unique Canadian NOC Regulations. The protection for patent owners is a helpful supplement to conventional patent infringement litigation. Indeed, there is no down side to listing on the Register. If Health Canada accepts the list for its Patent Register, the ball is then in the biosimilar manufacturer’s court to address non-infringement and validity issues before receiving an NOC. As such, biosimilar manufacturers may have to prepare for a delay in market access regardless of the merits of the patent owner’s case; where there is a patent on the Register, the patent owner ultimately controls whether the parties go to court and the statutory stay in marketing authorization during the NOC Proceeding is automatic. These factors raise significant barriers to freedom to operate in Canada.
1. Patented Medicines (Notice of Compliance) Regulations, SOR 93-133.
2. For a review of biosimilar drug regulations, see: Noel Courage and Ainslie
Parsons. The Comparability Conundrum: Biosimilars in the United States, Europe and Canada, (2011) 66 Food and Drug Law Journal, pages 203-224.
3. Health Canada, Health Products and Food Branch, Summary Basis of Decision (SBD) PrOmnitropeTM (Sep. 14, 2009), “Omnitrope Health Canada Approval”.
4. Health Canada, Health Products and Food Branch, Guidance for Sponsors: Information and Submission Requirements for Subsequent Entry Biology (SEBs), Mar. 5, 2010.
5. Health Canada Guidance Document, Patented Medicines (Notice of Compliance) Regulations (March 8, 2010), at page 8.
6. Amgen Canada Inc. et al. v. Teva Pharmaceutical Industries Ltd. et al. (T-989-12).
Noel Courage is a partner and patent agent with Bereskin & Parr LLP, Toronto, Canada. Noel can be reached at 416-957-1655 (firstname.lastname@example.org).