On Friday, the U.S. Court of Appeals for the Federal Circuit denied a petition to rehear by Apotex asking the Federal Circuit to reconsider a ruling that Apotex is barred from selling its generic version of the anticlotting drug Plavix while Apotex continues its five-year patent lawsuit with Sanofi-Aventis.
The trial began this week with Apotex urging that the underlying patent should be declared invalid saying that the development of Plavix was anticipated in a prior patent held by Sanofi and that its development would have been obvious to a person of ordinary skill in the field who examined the prior patent. Apotex also claims that Sanofi made several misstatements and omissions in its prosecution of the patent in the USPTO. The trial is expected to last about four weeks.
A reader recently asked the question about how often generics succeed in challenging branded drugs. I don’t have recent statistics for just generic drug challenges but some earlier studies for all patent cases showed that out of the 2,500 cases filed each year, barely one in seven terminates with a court’s judgment. Most of the remaining cases were settled. Thus, the vast majority of the patents remain intact. Of those patents that go all the way through to a court ruling, many do not survive validity challenges.
Approximately 40% of those patents challenged on validity grounds are found invalid on summary judgment. Assuming summary judgment of validity is survived, approximately 30% are found invalid at trial. However, validity is only one piece of the equation on whether the patent will survive. There are also equitable challenges so the cumulative effect of all validity and equitable challenges results in a patent surviving a challenge to its validity approximately 55% of the time.
On the question of pay-offs of generics to not introduce their drugs, things are never simple. As I mentioned above, generic-drug companies regularly make legal challenges to brand-name companies’ patents in the hopes of getting their generic versions on the market more quickly. They have little to lose. For the cost of a lawsuit, the generic company gets a shot at hundreds of millions (perhaps billions) of dollars in revenue.
The threat of a lawsuit claiming that the brand-name drug companies patent is invalid is close to being held at gunpoint since a jury may find the patent invalid and the drug company will be left twisting in the wind. Patent invalidity suits often come down to a nuanced, battle of experts trying to decide what some hypothetical person skilled in the art would or would not have found obvious a decade or two ago.
Read the full post here.