Federal Court of Appeal dismisses Mylan’s appeal of donepezil decision (ARICEPT)

On March 29, 2012, the Federal Court of Appeal (“FCA”) dismissed Mylan’s appeal of a decision of Justice Hughes (2011 FC 547) granting a prohibition order to Pfizer in respect of its donepezil product (Aricept) under the Patented Medicines (Notice of Compliance) Regulations.  The FCA decision is another in a recent string of decisions commenting on the uniquely Canadian doctrine of “promise of the patent” and its role in the assessment of utility/sound prediction.

At issue was the validity of two claims of Canadian Patent No. 1,338,808, one a compound claim and the other a therapeutic use claim.  Justice Hughes held that the “promise of the patent” was “that a new class of compounds has been discovered (donepezil being one) which, having regard to the cholinergic function theory of AChE inhibition, is effective for the treatment of Alzheimer’s”.  Justice Hughes went on to find that donepezil’s utility had not been demonstrated as of the patent’s filing date but that is was soundly predicted.

The FCA examined the expert evidence and held that it “overwhelmingly” confirmed Hughes J’s construction of the promise.  The FCA went on to conclude that Justice Hughes committed no error in his construction of the promise of the patent and accordingly dismissed this ground of appeal.

Mylan also appealed on the basis of insufficient/wrong data in the patent.  The FCA held that Justice Hughes was correct in not allowing Mylan to raise this issue because it was not in Mylan’s Notice of Allegation.  The FCA went on to find that, in any event, the data discrepancies raised were not material to the validity of the patent.

A copy of the Reasons for Judgment (2012 FCA 103) may be found here.