Prior Art Absorbs Bayer’s Oral Contraceptive Patent

Posted on | April 11, 2008 | No Comments

2008-1282 Bayer Schering v. Barr Pharma
D/NJ 05-CV-2308

Bayer has appealed Judge Peter G. Sheridan’s opinion invalidating its
patent for an oral contraceptive.  In 2005, Bayer filed its Complaint
under the Hatch Waxman Act to declare its Patent No. 6,787,531 valid
and to enjoin Barr from selling a generic form of Bayer’s Yasmin®.  After a healthy dose of discovery, extensive briefing and a two-week bench trial, Judge Sheridan
found the ’531 patent obvious, relying heavily on the Supreme
Court’s KSR decision.  Bayer’s claims required that a combination of
drospirenone and ethinylestradiol be micronized
and delivered in an immediate release tablet.  Bayer argued that the
prior art taught away from micronizing drospirenone as it would
degrade in the stomach and require an enteric coating—i.e., a pH sensitive coating that
wouldn’t degrade until it reached the small intestine.  The Court
disagreed, finding that:

• the prior art, viewed as a whole, did not teach away from micronizing the drug, as several references show that this type of drug benefits from micronization and that a closely related drug absorbed in the stomach; and
• the prior art taught that the use of enteric coatings caused variability that could not be tolerated in contraceptives that must be 99% effective, leading one of ordinary skill to use an immediate release tablet.

While Judge Sheridan noted that Bayer offered little testimony related to the typical secondary considerations for nonobviousness, he also made clear that such testimony would not have altered the Court’s opinion.  Punctuating that point, the Court went on to offer one additional basis for its opinion–Bayer’s drug combination was "obvious to try":

In
this case, the testimony was limited to discussion about whether or
not to employ two common formulation techniques – micronization and
enteric coating. As in KSR “there are a finite number of
identified predictable solutions.” In this case, based on the prior
art as a whole, micronizing and immediately releasing drospirenone
was obvious to try.

Additional coverage of this case can be found at the Orange Book Blog. 

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