Case: Alcon Canada Inc. et al. v. Cobalt Pharmaceuticals Company et al.

Drug: Moxifloxacin hydrochloride [VIGAMOX®]

Nature of case: Prohibition Application pursuant to PM(NOC) Regulations

Successful party: Divided success

Date of decision: May 4, 2014

Summary

This latest decision from the Federal Court is consistent with a recent trend towards a more literal construction of patent claims.  The Court preferred not to broaden the promise of the patent and instead adopted a construction that fairly reflects the intention of the inventor based on a plain reading of the text of the patent.

Alcon Canada Inc., Alcon Pharmaceuticals Ltd. and Bayer Intellectual Property GmbH GP (“Alcon”) brought an application pursuant to section 6 of the Patented Medicines (Notice of Compliance) Regulations for an order prohibiting the Minister of Health from issuing a Notice of Compliance to Cobalt Pharmaceuticals Company (“Cobalt”) in respect of a generic version of the drug VIGAMOX®.  VIGAMOX® is the most commonly used antibacterial eye drop containing the medicinal ingredient moxifloxacin hydrochloride.  It is covered by Canadian Patent Nos. 1,340,114 (the “’114 Patent), 2,342,211 (the “’211 Patent”) and 2,192,418 (the “’418 Patent”).

The Court allowed Alcon’s application for a prohibition order with respect to the ‘114 Patent, which claims a class of compounds of which moxifloxacin is one.  The Court found that Cobalt’s allegation of invalidity on the basis of obviousness and a lack of sound prediction and utility was not justified.

The Court dismissed Alcon’s application for a prohibition order with respect to the ‘211 Patent, which claims certain uses for moxifloxacin, and the ‘418 Patent, which claims the monohydrate form of moxifloxacin.  The Court found that Cobalt’s allegation of obviousness with respect to the ‘211 Patent was justified and that Cobalt’s allegation of non-infringement of the ‘418 Patent was justified.

The ‘114 Patent – Genus patent which includes claims for moxifloxacin

Claim Construction

The ‘114 Patent claims a novel class of quinolones distinguished by a fused pyrrolidine bicycle at the C-7 position of the quinolone ring.  This class of compounds is said to have high antibacterial activity, particularly against Gram-positive bacteria.  The specific compound moxifloxacin and its enantiomers are claimed in Claims 8 and 13 of the ‘114 Patent.  The Court rejected Cobalt’s submission that a single reference to low toxicity in the ‘114 Patent and a list of possible bacteria that can be treated with the class of compounds were essential elements of every claim.  

Utility/Sound Prediction

The Court began its utility analysis by considering whether the inventors of the ‘114 Patent made a specific promise.   The Court held that to the extent the ‘114 Patent promises anything, it is limited to a promise that the class of quinolones as a whole will have in vitro activity against a broad spectrum of bacteria.  The Court rejected Cobalt’s reliance on a single reference to low toxicity in the patent and a list of pathogens and medical conditions that may be treated by the class of quinolone compounds as forming part of the promise.  If the inventors had intended to make these promises, the patent would have been drafted to make the promise more explicit.  The Court held that references to low toxicity and pharmaceutical uses are descriptions of hopes or potential uses, not promises.

Since moxifloxacin was not synthesized or tested prior to the filing date of the ‘114 Patent, the utility of moxifloxacin was based on a sound prediction.  The factual basis for the prediction of utility of the claims to moxifloxacin is the Maximum Inhibitory Concentration [MIC] test results in the ‘114 Patent for Example 15.  Moxifloxacin is not an Example compound in the ‘114 Patent although it closely resembles Example 15 except for having a different substituent at the C-8 position on the quinolone ring.  The Court accepted that it was common general knowledge that the substituent at the C-8 position of moxifloxacin was expected to retain high activity and that the effect of chirality which is further from the quinolone core has little impact on activity.  As such, Alcon argued and the Court accepted that the inventors had a sound basis for predicting that moxifloxacin had at least the same if not higher antibacterial activity than the compound  in Example 15 of the ‘114 Patent.

Disclosure

Cobalt alleged that the public’s right to disclosure was denied in the ‘114 Patent because, like the patent in Teva Canada Ltd. v. Pfizer Canada Inc., 2012 SCC 60, the ‘114 Patent claims millions of compounds but obscures the identity of moxifloxacin.  The Court rejected Cobalt’s submissions.  The Court found no evidence that the inventors of the ‘114 Patent excluded information from the patent for an improper purpose or that they intentionally misled the public.  Further, there was no evidence before the Court that certain compounds were inactive.  Finally, to the extent that there were some minor discrepancies between the data provided for the example compounds in the ‘114 Patent and the compounds tested in lab notebooks, these discrepancies were not sufficient to invalidate the patent.

Obviousness

The parties agreed that the inventive concept of the ‘114 Patent is the claimed compounds’ unique fused pyrrolidine bicycle at the C-7 position of the quinolone ring and accompanying high antibacterial activity.  Cobalt argued that the choice of modifying the C-7 position on the quinolone ring was obvious and that the choice of a fused pyrrolidine bicycle substituent was obvious.  The Court rejected both of these positions.

The Court held that numerous prior art references showed that many other positions on the quinolone ring were being investigated for antibacterial activity and that there was nothing in the art suggesting that a fused pyrrolidine bicycle conferred enhanced antibacterial activity.  The Court was also persuaded by the actual course of conduct that culminated in the invention, including the extensive work in making hundreds of compounds annually with modifications at nearly all positions on the quinolone ring.  As such, the Court concluded that Cobalt’s allegation of obviousness had not been made out.

The ‘211 Patent – Claims uses for moxifloxacin

Claim Construction

The ‘211 Patent claims the use of moxifloxacin in a concentration of between 0.1 to 1.0 wt% as an antibiotic agent in a pharmaceutical composition for use in the treatment and prevention of ophthalmic infections.  It further claims the pharmaceutical composition itself, and the use of the composition for topically treating or preventing ophthalmic infections.

Obviousness

The Court held that the inventive concept of the ‘211 Patent is a pharmacological composition for topically treating or preventing an ophthalmic infection, which comprises 0.1 to 1.0 wt% of moxifloxacin.  In light of the common general knowledge as of the priority date of the ‘211 Patent, the Court found that the use of moxifloxacin in a topical ophthalmic formulation for the treatment of bacterial infections was obvious or obvious to try.  The Court’s finding was primarily based on the fact that Ciprofloxacin, another quinolone antibiotic, was sold commercially in solution for the treatment and prevention of ocular infections, as were other quinolones such as Ofloxacin.  Therefore, it was obvious to try to treat ophthalmic infections with moxifloxacin.  

According to the Court, the claims of the ‘211 Patent were directed to a known compound being used for a known use in a concentration known to be effective.  As such, Cobalt’s allegation of invalidity on the basis of obviousness was justified and the Court dismissed Alcon’s prohibition application in respect of the ‘211 Patent.

The ‘418 Patent – Claims monohydrate form of moxifloxacin

Claim construction

The ‘418 Patent claims the monohydrate form of moxifloxacin having two characteristic peaks, which is said to have improved stability over the anhydrous form.  It also claims the prism crystal form of moxifloxacin monohydrate, which is said to be more free-flowing than the needle crystal form.  The Court held that Claim 1 of the ‘418 Patent contained three essential elements: (1) the compound moxifloxacin monohydrate; (2) the compound displays a characteristic band in the powder X-ray diffractogram at 2O = 26.7; and (3) the compound displays a characteristic peak in the 13C-NMR spectrum at 168.1 ppm.  The Court rejected Alcon’s argument that it only needed to show that Cobalt’s product had either a characteristic band or a characteristic peak but not both.

Infringement

The parties accepted that Cobalt’s finished product did not infringe the ‘418 Patent.  Alcon argued that Cobalt infringed the ‘418 Patent through its manufacturing of its moxifloxacin product and based its argument that Cobalt’s process uses moxifloxacin monohydrate on the data provided in Cobalt’s ANDS.  The Court held that while Cobalt’s ANDS is suggestive of a process that uses moxifloxacin monohydrate, including XPRD data which showed the characteristic band claimed in the ‘418 Patent, there was no 13C-NMR data available regarding Cobalt’s process.  Since the 13C-NMR characteristic peak is an essential element of Claim 1 of the ‘418 Patent, the Court held that infringement had not been established on the evidence.

The Court declined to draw an inference, in the absence of actual evidence from Cobalt’s process, that because the other elements of Claim 1 have been met, it necessarily follows that a characteristic peak at 168.1 ppm would be present in Cobalt’s process. The Court held that a possibility of infringement is not enough to rebut the presumption of the truth of the allegations contained in a Notice of Allegation.  The Court stated at para. 230: “Whatever the criticism of Cobalt for not producing 13C-NMR data, it was Alcon’s burden to do as much as reasonably possible to establish infringement.  In my view, they did not do so and did not advance a good reason for not putting forward the best evidence.”  The Court was not prepared to accept assumptions from experts when better objective evidence could have been produced.  As such, Cobalt’s allegation of non-infringement of the ‘418 Patent was found to be justified.

Link to decision

Alcon Canada Inc. v. Cobalt Pharmaceuticals, 2014 FC 462