Continuing from our last post where we briefly discussed about the background of rejection of patent application for beta-crystalline variant of imatinib mesylate, Novartis writ petition to challenge the Chennai Patent Office decision and finally the Appellate Board denying the patent application for beta-crystalline variant. Now we will discuss and analyze the findings of the Appellate Board. The main issues raised and discussed were – (1) priority date, (2) novelty/anticipation, (3) inventive step/non-obviousness, (4) selection patent, and (5) section 3(d).
Issue regarding the priority date was decided in the favor of Novartis citing judgment made by Calcutta High Court in Agouron Pharmaceuticals Inc. v. Controller of Patents (AID No. 2 of 2001). The Appellate Board specifically reasoned that issue of priority date for mail-box application need to be considered as per situation on the date of examination not from the date of filing of application.
Novelty/anticipation issue was also decided in favor of Novartis. The Appellate Board specifically reasoned that none of prior art references produced by the Opposing parties disclose or anticipated beta crystalline variant of imatinib mesylate. Discussing anticipation, the Appellate Board also acknowledged the doctrine of enablement and concluded that a person skilled in the art just cannot predict the polymorphism and prepare beta-crystalline imatinib mesylate from EP 0564409 (disclosing imatinib free base and salts thereof) disclosure.
Inventive-step/non-obviousness issue too was decided in favor of Novartis. The Appellate Board specifically reasoned that the Opposing parties has not submitted any evidence that any person has prepared imatinib mesylate and found it to be present only in beta-crystal form prior to the application for beta-crystalline imatinib mesylate. Apart from this, the Appellate Board combined the selection patent argument made by Novartis counsel to strengthen inventive-step of the beta-crystalline form.
Selection patent issue as we already mentioned in our last post, helped Novartis to constitute inventive step for its beta-crystalline imatinib mesylate. The Appellate Board reasoned following minimum guidelines for a patent to be a selection patent.
(1) Whether there is any statement in the specification where the nature of the invention concerns with some kind of selection.
(2) Whether the selection is from a class of substances which is already generally known.
(3) Whether the selected substance in new.
(4) Whether the selection is a result of any research by human intervention and ingenuity opposed to mere verifications.
(5) Whether the selection is unexpected or unpredictable.
(6) Whether the selected substance possesses any unexpected and advantageous property.
The Appellate Board found that patent application for beta-crystalline variant of imatinib mesylate satisfied all the minimum requirements of above guidelines (though we leave it for our readers to decide the merit of the Appellate Board reasoning to reach such satisfaction).