A recent decision of the Federal Court of Canada will hopefully lead to clarity on whether vaccines containing an adjuvant are eligible for Certificates of Supplemental Protection in Canada. The decision is especially timely as researchers around the world are rushing to develop a vaccine against the COVID-19 virus.
Certificates of Supplemental Protection (CSPs) provide patent term restoration for up to two years for eligible patents relating to human and veterinary drugs. This additional protection is intended to partly compensate for time spent in research and obtaining marketing authorization for new drugs.
CSPs are relatively new in Canada, having been introduced on September 21, 2017, as part of the Comprehensive Economic and Trade Agreement (CETA) between Canada and the European Union. To date, the Canadian Government has issued 39 CSPs – 36 to drugs for human use and 3 to drugs for veterinary use.
GlaxoSmithKline Biologicals S.A. (GSK) requested a CSP for its Canadian Patent No. 2,600,905 (the ‘905 Patent) and its drug SHINGRIX®. The ‘905 Patent describes a new vaccine useful in the prevention or amelioration of shingles in adults older than 50, or in immunocompromised persons. The ‘905 Patent specifically describes compositions capable of inducing an immune response against the Varicella Zoster Virus, for example, the combination of an antigen and an adjuvant. Adjuvants are substances that enhance the immune response to an antigen.
The Canadian Minister of Health (the Minister) refused GSK’s CSP application, primarily on the basis that in order to be eligible for a CSP, “a patent must include at least one claim limited to one or more medical ingredients or to their use” and that the ‘905 Patent doesn’t meet this requirement because each of the claims in the patent include a non-medical ingredient (i.e., an adjuvant). This was the case even though the adjuvant of SHINGRIX® is biologically active and essential to its clinical efficacy because the Minister made its decision in line with Health Canada’s licensing guidelines that treat both biologically active and biologically inactive adjuvants as inactive excipients. The Minister also considered that vaccine adjuvants cannot be medicinal ingredients because they do not independently cause an immunological reaction (i.e., they must work in concert with an antigen).
GSK sought judicial review of the Minister’s decision. The issue before the Federal Court was whether the Minister’s decision to refuse GSK’s CSP was reasonable in view of the Minister’s restrictive definition of “medicinal ingredient”.
The Federal Court’s decision (2020 FC 397) is the first time that a Canadian Court has been asked to judicially review the refusal of a CSP. After reviewing the parties’ evidence and the statutory purpose of the CSP, the Federal Court found that the Minister’s decision was not reasonable and expressed a number of concerns in its reasons.
For example, the Federal Court noted that the Minister needed to interpret the Canadian law implementing CETA “in a manner consistent with [CETA]”. So, while CETA does not define the term “medicinal ingredient”, CETA does define a protected product as “the active ingredient or combination of active ingredients” of an authorized pharmaceutical product. Thus, according to CETA, whether a product is eligible for CSP protection depends on whether the product has biological activity.
Regarding the Minister’s position that vaccine adjuvants cannot be medicinal ingredients because they do not independently cause an immunological reaction, the Federal Court held that this was not tenable, since neither the antigen nor the adjuvant independently could provide “a clinically useful response”. The Federal Court went on to note that the Minister’s position would excludes CSP protection for many novel vaccines, which requires adjuvants.
The Federal Court also noted that while Health Canada considers adjuvants to be excipients and treatments them in the same way stabilizers, fillers, and preservatives for licensing purposes, there is no practical purpose for “excluding adjuvanted vaccines from the CSP regime”.
Interestingly, although the Federal Court had the above concerns, it did not direct the Minister to issue a CSP to GSK, claiming that that the present case was not an appropriate case to do so. The Federal Court therefore sent the CSP application back to the Minister for reconsideration in view of the Court’s reasons. The Minister must now reconsider their decision to refuse the CSP or appeal the Federal Court’s decision to the Federal Court of Appeal. Although this story is far from over, it is promising news for innovators seeking to obtain CSPs for vaccines in Canada.