November 17, 2009, drospirenone/ethinyl estradiol

The Court dismissed a judicial review of the Minister’s decision refusing to list a formulation patent on the Patent Register.

The patent at issue contains formulation claims, but only specifically referred to one of the medicinal ingredients in the approved combination product. The Court focused on the question of interpretation of the NOC Regulations, holding that it must look at the plain and ordinary meaning of the full phrase “a claim for the formulation that contains the medicinal ingredient”.

The Court then held that a formulation is essentially a physical mixture of medicinal and non-medicinal ingredients and that a mixture containing two medicinal ingredients is different from a mixture that contains only one. The drug with one medicinal ingredient will have a different effect from a drug with two medicinal ingredients where two medicinal ingredients are combined to have a desired effect.

The Court considered Bayer’s argument that the interpretation of this section is different than the interpretation of a claim to the medicinal ingredient section of the Regulations but disagreed. The Court held that there is a fundamental difference between a compound patent and a formulation patent. A compound patent containing a single medicinal ingredient will necessarily be early-worked if a generic company tries to copy the product as the essence of a compound patent is the medicinal ingredient. But the essence of a formulation patent is the mixture of all ingredients. This distinction requires a different approach when matching of specificity is being considered. A formulation patent eligible for listing must contain a claim for the approved mixture of medicinal and non-medicinal ingredients that are actually administered to the patient.

The full text of the decision can be found at: