April

Case Name: Bayer Pharma AG v. Watson Labs., Inc., Civ. No. 12-cv-517 (GMS), 2016 U.S. Dist. LEXIS 55752 (D. Del. Apr. 27, 2016) (Sleet, J.)

Drug Product and Patent(s)-in-Suit: Staxyn® (vardenafil hydrochloride trihydrate); U.S. Patent No. 8,613,950 (“the ’950 patent”)

Nature of the Case and Issue(s) Presented: Watson asserted that that claims of the ’950 patent were invalid as obvious for two reasons: (i) combining vardenafil hydrochloride trihydrate with the sugar alcohol excipients mannitol and sorbitol into a known orally disintegrating tablet (“ODT”) dosage form was taught by the prior art and would have been obvious to the person of ordinary skill, particularly in view of the taste profiles and favorable disintegration properties of the sugars; and (ii) competitive pressure would have motivated one skilled in the art to derive the claimed subject.

Bayer responded that one of skill would not have been motivated to modify the dosage type of vardenafil to ODT as there were no known problems with the digestible version of vardenafil in Levitra®. In addition, there were very few ODT formulations on the market or being contemplated at the time of the invention. Lastly, one of skill would not be motivated to use an ODT dosage with vardenafil because of the taste profile.

The court agreed with Bayer and found that Watson had not met is clear and convincing burden of proving invalidity by obviousness.

Why Bayer Prevailed: The court agreed with Bayer that one of skill would not have modified the digestible version of vardenafil into an ODT dosage form because there had not been any known problems with the digestible version. Further, literature at the time demonstrated that ODT dosage forms were not that common, and, in particular, no compound or contemplated compound to treat erectile dysfunction was offered in an ODT dosage form. The court also rejected Watson’s argument that one of skill would have used her own personal taste to determine if an ODT dosage form of vardenafil would be sufficient. Lastly, the court found that the evidence in the prior art contemplated the use of only one sugar in such formulations, and not two as suggested by Watson.

The court also found that secondary considerations of non-obviousness favored Bayer. In particular, there were unexpected results related to the bioavailability of the ODT dosage form as compared to the digestible form. Likewise, there was evidence that Watson did copy the claimed invention, and not just simply by filing an ANDA.