A recent decision of the Singapore High Court suggests that it is best for those seeking to register generic versions of pharmaceutical products to disclose all potentially relevant patents relating to those products, even if some or all of those patents do not cover the product as such.  Disclosure is a requirement under Singapore's patent linkage scheme.

Millennium only had process patents, so Zyfas did not declare them

  • The plaintiff ('Millennium') was the registered owner of various process patents relating to the anticancer drug "bortezomib".
  • The defendant ('Zyfas') applied to register a therapeutic product for a generic version of bortezomib with the Health Services Authority (HSA). This registration was subsequently allowed.
  • Bortezomib was not covered by any existing product patents in Singapore.
  • Zyfas admitted that they were of the view that only product patents had to be declared under the patent linkage provisions of Regulation 23(2) of the Health Products (Therapeutic Products) Regulations 2016 ('TPR').
  • Millennium requested from the Court a declaration that Zyfas had made a misleading statement. This was granted. Zyfas appealed.

What were the potential consequences for Zyfas?

At stake in this case was the potential for Millennium to seek cancellation of Zyfas' product registration.

Under Regulation 24 of the TPR, the HSA has the discretion to cancel the registration of a therapeutic product if (among other things) it is satisfied that a court has determined that the declaration made under Regulation 23(2) contains a statement that is false or misleading in a material particular or omits to disclose any matter that is material to the application.

The Court's conclusion – the omission need not be a "knowing" or "intentional" omission

Zyfas conceded that the requirement under Regulation 23(2) (a) to disclose "whether a patent under the Patents Act is in force in respect of a therapeutic product" included the disclosure of existing process patents in respect of the therapeutic product.  This concession appears to have been made in light of the decision of the Court of Appeal in Millennium Pharmaceuticals, Inc v Drug Houses of Australia Pte Ltd and another appeal [2019] SGCA 31 ("Drug House case").

Zyfas further accepted that the existence of the process patents was "a matter that [was] material to the defendant's application" under Regulation 24(1)(a)(ii) of the TPR.

Therefore, the only issue for the Court to consider was whether Zyfas had omitted to disclose the existence of the process patents. The answer to this turned on the following question of interpretation: whether an operative omission under Regulation 24(1)(a)(ii) of the TPR requires that the defendant knowingly or intentionally omits to state the existence of relevant patents.

From a normal reading of Regulation 24 the Court considered that there was nothing requiring mental elements of knowledge or intention. This interpretation was reinforced by the neighbouring provision of Regulation 25 of the TPR (which deals with offences for making false patent declarations) which uses positive phrases like "person knows or has reason to believe is false" and "intentional suppression".  Incidentally, contravention of Regulation 25 imposes criminal liability.

The appeal was therefore ultimately dismissed with the Court granting Millennium the declaration sought.

Lessons learned, and what is likely to happen next?

This highlights the fatal nature of making false or misleading declarations or omitting to disclose all matter material to the application.  But what types of patents would be deemed "material" and should be declared? This threshold test for materiality is somewhat clarified in the Drug House case which stated (in relation to the requisite patent linkage declaration):

"the applicant for registration has to declare the patents and then state, among several possibilities, that the patents are invalid and will not be infringed by doing of the act for which the registration of its product is sought. It is then for HSA to decide whether to invoke reg 23 (5) of the TPR to require the Respondent to serve the requisite notice on the Appellant."

From the above case it would appear that a conservative approach to declaring patents should be adopted, including declaring process, use (second-medical treatment), and formulation patents, which relate to the product to be registered.

The ultimate take home message here is to ensure proper patent due diligence is performed to identify all potentially relevant patents and have these declared to the HSA.

In relation to this decision it would appear that the next step for Millennium will be to apply to the HSA, court order in hand, to have the Zyfas registration cancelled.

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