On August 17, 2016, in Janssen Biotech, Inc. v. Celltrion Healthcare Co., District of Massachusetts Judge Mark Wolf faced a double patenting fact pattern that had not been adjudicated in a district court case since the Federal Circuit decided Gilead Sciences Inc. v. Natco Pharma Ltd.i Judge Wolf held U.S. Patent No. 6,284,471 (the "'471 patent") invalid for obviousness-type double patenting over U.S. Patent No. 6,790,444 (the "'444 patent") because the '471 patent expired later due to the changes to patent terms under the Uruguay Round Agreements Act ("URAA"), even though both patents claim priority to the same application and the '471 patent issued years before the '444 patent.ii

Background and Gilead

Obviousness-type double patenting, as an invalidity defense in patent litigation, is less common than novelty and nonobviousness defenses under sections 102 and 103 of the Patent Act.iii Janssen Biotech, however, is the second case in two years in which a court invalidated a patent on an FDA-licensed biological product ("branded biologic") for obviousness-type double patenting. The first case involved a patent that covered the biologic drug Humira, and the Federal Circuit invalidated that patent for obviousness-type double patenting in 2014.iv In Janssen Biotech, the '471 patent covered the biologic drug Remicade. In each case, the branded biologic owner sued an applicant seeking approval to market a "biosimilar" drug under the section 351(k) abbreviated approval pathwayv in the Biologics Price Competition and Innovation Act, and the biosimilar applicant asserted obviousness-type double patenting as a defense.

The doctrine of double patenting prevents the unjustified extension of patent protection beyond a single patent term. Under the doctrine, two patents cannot have different terms if they claim the same subject matter (statutory double patenting) or "patentably indistinct" obvious variations of the same subject matter (obviousness-type double patenting). Double patenting can apply whenever patents share a common owner or inventor, and recent statutory changes restricting certain commonly owned patents from being available as prior art may make double patenting defenses more prevalent.vi

Obviousness-type double patenting is a judicially-created doctrine, but it is grounded in section 101 of the Patent Act. Courts have historically applied it to invalidate a later-issued patent claim that is patentably indistinct from an earlier-issued patent claim. More recently, however, in Gilead, the Federal Circuit applied the doctrine to invalidate an earlier-issued patent claim over a later-issued patent claim because the later-issued patent was the first to expire.vii The Federal Circuit held that "looking to the expiration date instead of issuance date" is an appropriate application of the obviousness-type double patenting doctrine.viii In Gilead, the patents expired at different times because they each claimed priority to a different application.ix

The Janssen Biotech Patents

The patents in Janssen Biotech, like the patents in Gilead, expired in the reverse order of their issuance, i.e., the earlier-issued '471 patent had a later expiration date than the laterissued '444 patent. But unlike in Gilead, the patents in Janssen Biotech expired in reverse order solely due to a change in the law--not because they had different priority dates. The '471 patent and the '444 patent had the same priority date--they both claimed priority to the same parent application filed in 1991. The '471 patent issued from a continuing application filed in 1994, while the '444 patent issued from a continuing application filed in 2001. Under the URAA, codified at 35 U.S.C. 154, patents filed before June 8, 1995 (pre-URAA patents), like the '471 patent, have terms that run seventeen years from the patent issue date, while patents filed on or after June 8, 1995 (post-URAA patents), like the '444 patent, have terms that run twenty years from the earliest effective filing date. The result in Janssen Biotech was that the '444 patent had a term that ran twenty years from its 1991 priority date--expiring in 2011, while the '471 patent term runs seventeen years from its 2001 issue date--expiring in 2018. Those dates are shown herex:

Click here to view the image.

At one time, it appeared as though the URAA changes, measuring patent terms from their filing dates, would limit the prevalence of double patenting,xi but here, the URAA caused the patents to expire at different times.

In holding the '471 patent invalid over the '441 patent, Judge Wolf noted that the URAA "was not intended to alter the judicial doctrine of obviousness double-patenting."xii Accordingly, the court held that "the reasoning in Gilead applies where, as here, the later-issued patent expires earlier because of the change to patent terms resulting from the [URAA]."xiii

Looking Forward

Janssen intends to appeal the decision, which will give the Federal Circuit an opportunity to decide whether Gilead properly applies to invalidate a later-expiring patent whose later expiration is due to the URAA.xiv