Indivior Inc. v. Dr. Reddy’s Labs., S.A.

Case Name: Indivior Inc. v. Dr. Reddy’s Labs., S.A., No. 2017-2587, 2018-1010, -1058, -1062, -1114, -1115, -1176, -1177, -1949, -2045, 2019 U.S. App. LEXIS 20680 (Fed. Cir. July 12, 2019) (Circuit Judges Newman, Mayer, and Lourie presiding; Opinion by Lourie, J.; Dissent by Mayer, J.) (Appeal from D. Del., Andrews, J.)

Drug Product and Patent(s)-in-Suit: Suboxone® (buprenorphine / naloxone) Film; U.S. Patents Nos. 8,603,514 (“the ’514 patent”), 8,900,497 (“the ’497 patent”), 8,017,150 (“the ’150 patent”)

Nature of the Case and Issue(s) Presented: Indivior asserted three patents that cover its sublingually administered Suboxone film product. The ’514 and ’497 claim a method of using only bottom heat to create a uniform distribution of API in a pharmaceutical film. The ’150 patent claims a pharmaceutical film composition comprising API, polyethylene oxide, and hydrophilic cellulosic polymer (“HCP”).

The district court held four bench trials. In the first trial, defendant Watson did not seek construction of the bottom-heat drying limitation of the ’514 patent. The district court found that Watson infringed and that the asserted claims were not invalid as indefinite. In the second and third trials, respectively, Dr. Reddy’s Laboratories (“DRL”) and Alvogen Pine Brook (“Alvogen”) obtained constructions of the ’514 and ’497 patents that excluded drying methods that solely use conventional top drying techniques. Based on this construction, both ANDA products were found not to infringe. The district court ruled that the patents were not invalid as obvious. In the fourth trial, DRL was found not to infringe the ’150 patent under the doctrine of equivalents.

Why defendants DRL and Alvogen Prevailed: On appeal, concerning the district court’s finding of non-infringement of the ’514 and ’497 patents, Indivior made two primary arguments: (i) that the district court incorrectly construed the drying limitation; and (ii) even under this construction, Indivior sufficiently demonstrated infringement. As to the former, the Federal Circuit explained that the district court’s construction was correct because the patent specifications and prosecution history made express statements that repeatedly disparaged conventional top drying methods. As to the latter argument, the Federal Circuit explained that the district court did not err in determining that the sole source of heat in the drying process was hot air coming from above the film and that any bottom drying was merely incidental.

With respect to the district court’s finding that DRL did not infringe the ’150 patent, Indivior argued that the district court erred in finding that DRL’s use of polyvinyl pyrrolidone (“PVP”) did not infringe the HCP limitation under the doctrine of equivalents.  The Federal Circuit disagreed, noting that the specification taught that PVP, an unclaimed embodiment, was an alternative to HCP. In other words, PVP was dedicated to the public, meaning it could not be recaptured through the doctrine of equivalents.

Why Indivior prevailed as against Watson: Watson argued that the district court erred in finding that its product infringed a viscosity limitation of the ‘514 patent. The Federal Circuit concluded that Watson could not demonstrate clear error in the court’s judgment and affirmed.

Finally, the Federal Circuit found that the ‘514 patent was not invalid as obvious. In particular, defendants failed to demonstrate that the prior art taught the claimed API limitations or that the prior art disclosed uniform dried films. The defendants also argued that the ʼ514 patent was invalid as indefinite because it recited a physical impossibility: “a flowable yet solid cast film.” The Federal Circuit disagreed, explaining that the flowable matrix is first flowable and then dried.

As to the ’150 patent, the Federal Circuit found that Indivior demonstrated sufficient written description support to claim priority to its original provisional application, thereby antedating DRL’s asserted art.

In his dissent, Judge Mayer stated that there was “no need for this court to reach the issue of infringement because the three patents … asserted by [Indivior] are invalid as obvious.” According to Judge Mayer, the ’497 and ’514 patents are obvious because before their priority dates, multiple prior art references taught both methods to manufacture sublingual films and techniques for achieving film content uniformity. With respect to the ’150 patent, it is obvious because the district court erred in concluding that it can claim priority to the 2003 filing date of its parent application, the ’902 application. In particular, the ’902 application nowhere conveys possession of the specific polymer component recited in independent claim 1 of the ’150 patent. That claim requires low molecular weight polyethylene oxide (“PEO”), high molecular weight PEO, and a hydrophilic cellulosic polymer (“HCP”), and further specifies that the low molecular weight PEO must be at least 60% of the polymer component and that the HCP can be no more than 25% of the polymer component. But the ’902 application does not suggest possession of a polymer component including at least 60% low molecular weight PEO and at most 25% HCP. For those reasons, the district court erred in concluding that lndivior was entitled to rely on the 2003 priority date of the ’902 application, the asserted claims of the ’150 patent are invalid as obvious.