The Federal Court has decided an infringement action concerning risedronate products under the Patented Medicines (Notice of Compliance) Regulations (the Regulations). The Court dismissed allegations of anticipation based on prior art, as well as arguments that the asserted claims were invalid due to lack of demonstrated utility, insufficiency of disclosure, and/or overbreadth. However, the Court also found that neither direct nor indirect infringement were established.

Background

Allergan Inc. markets ACTONEL DR® in Canada for the treatment of osteoporosis. ACTONEL DR® is an enteric-coated delayed release tablet containing risedronate and ethylene-daimine-tetraacetic acid (EDTA). ACTONEL DR®is said to differ from other risedronate formulations in that it could be taken with food, overcoming a “food effect” that was a limitation of other bisphosphonate products.

Apotex Inc. (Apotex) submitted an Abbreviated New Drug Submission to obtain approval for a generic oral 35 mg sodium risedronate tablet (the Apotex Product). Allergan Inc. and Allergan Pharmaceuticals International Limited (together, Allergan) brought an infringement action under subsection 6(1) of the Regulations, arguing that the Apotex Product will infringe its Canadian Patent No. 2,602,188 (the 188 Patent), which is listed on the Patent Register against ACTONEL DR®. Apotex argued non-infringement and invalidity in defence.

188 Patent Valid But Not Infringed

Claims Construction. All of the claims in dispute related to an oral risedronate dosage form “for use with or without food or beverage intake”. The Court held that this term was clear and did not require interpretation: it means that the patient has a choice. In reaching this finding, the Court rejected Allergan’s argument that the claim is a “product claim” because the manner of use is an essential element. The Court also rejected Allergan’s argument that “for use”, in this context, should be construed to mean “suitable for use”. This issue was later picked up in the infringement analysis.

Anticipation. Apotex argued that the subject-matter of the 188 Patent was previously disclosed and enabled byBrazilian Patent Application 0106601 (BR 601), which is referenced in the 188 Patent. The Court disagreed. BR 601 neither describes nor addresses the problem addressed in the 188 Patent. Although the “ingredients” of the 188 Patent were “buried in the very broad disclosure of BR 601”, it did not provide clear direction to the skilled person about what “ingredients” to choose, and in what amounts. Even if a skilled person made “all the right choices” from BR 601, it still did not disclose pharmaceutically effective absorption in the fed or fasted states, nor did it address the food effect. Therefore, the result was not inherently disclosed. The Court also found no enablement.

Obviousness. The Court held that the 188 Patent was not obvious. BR 601 was prior art, but the skilled person would have considered that: (1) it was only an application (not an issued patent); and (2) they would be unaware of BR 601’s inventor and pharmaceutical company. Even if the skilled person had combined BR 601 together in a mosaic with the other prior art, it would not have been self-evident to try to combine risedronate with EDTA in an enteric coating with an immediate release to achieve pharmaceutically effective absorption. Nor was it more or less self-evident that this combination would even work when administered with or without food.  

Inutility, insufficiency, and overbreadth. The Court found that the 188 Patent was not invalid for inutility, insufficiency, or overbreadth. The Court rejected Apotex’s inutility argument that higher coating formulations in a study would not achieve pharmaceutically effective absorption, finding that a test result should be considered in light of all the tests. The Court also found that the patent contained sufficient detail to put the invention into practice.

Non-infringement. The Court found that Apotex would not directly or indirectly infringe the 188 Patent’s asserted claims. As described in its product monograph (PM), the Apotex Product is restricted to use with food – it is not for use with or without food. This restriction related to a risk of abdominal pain, not absorption.

Allergan argued that Apotex’s intentions and how the Apotex Product will ultimately be used are irrelevant – the claims only require that the Apotex Product be “suitable for” use with or without food or beverage intake. The Court rejected this argument. Despite the fact that Apotex conceded that its product will achieve pharmaceutically effective absorption with or without food, the Court emphasized that the dosing instructions for the product do not give the patient a real choice of when and how to take the medication.

The Court noted that because the food restriction in the Apotex Product PM was also present in Allergan’s PM for ACTONEL DR®, Allergan’s patent does not cover its own product.

Costs

The Court awarded lump sum costs in favour of Apotex in the amount $1,604,416.08, which represented 25% of fees plus $492,420.64 in disbursements. The Court analysed costs on the basis that Allergan had commenced the action for infringement and had failed to make out that allegation. Even though Allergan successfully defended against many invalidity attacks and a significant portion of costs were devoted to these issues, the Court found that it could not consider this a “divided success”.

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Allergan Inc. v. Apotex Inc., 2022 FC 260