The Full Court of the Federal Court recently upheld the trial judge's invalidation of one of the Lipitor patents for false suggestion or misrepresentation.

In Ranbaxy Australia Pty Ltd v Warner-Lambert Company LLC [2008] FCAFC 82, the patent in dispute was a selection patent related to a supposedly particularly effective form of atorvastatin calcium, the active ingredient in the blockbuster drug Lipitor.

In the specification and during prosecution of the patent, the patentee had asserted that the particularly effective form was 10 times more effective than the normal form. Whilst certain test results could be construed as supporting this assertion, the court found that, on the evidence, the skilled expert would have discounted these results. The evidence supported the assertion that the effective form was only twice as effective, which was also held to be an expected result.

As a consequence, the assertions in the specification and during prosecution that the particularly effective form was 10 times more effective doomed the patent. Whilst the main Lipitor patent was held valid, the particularly effective form of the atorvastatin calcium patent was held to be obvious (and hence reduced the ability of the patentee to extend the length of the main patent).

The case shows that patentees in Australia may be held to a harsh standard for any statements or results presented in the specification or during prosecution, right up to the grant of a patent, and perhaps beyond.

Peter Treloar

Shelston IP
Level 21, 60 Margaret Street
Sydney NSW 2000
Australia
Tel: +61 2 9777 1111
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