Opinion ID: 807367
Heading Depth: 2
Heading Rank: 2

Heading: Lilly’s Patents

Text: In conjunction with their antifolate research, the inventors filed U.S. patent application 07/448,742 (the “’742 application”) on December 11, 1989. The ’742 application disclosed and claimed pemetrexed as well as a broader group of related antifolates containing pemetrexed’s characteristic core structure. The ’742 application, though itself eventually abandoned, founded a family of related applications that ultimately yielded the three patents at issue in this appeal. The ’932 patent issued on September 6, 1994, from an application filed on March 22, 1991, claiming priority from the ’742 application through a series of continuations. Claim 3 of the ’932 patent claims pemetrexed. Claims 1, 2, and 7 are generic, Markush-style claims that encompass pemetrexed as well as other structurally related antifolates. U.S. Patent 5,028,608 (the “’608 patent”) issued on July 2, 1991, from an application filed on May 24, 1990, as a continuation-in-part of the ’742 application. The ’608 patent claims, inter alia, an antifolate (the “’608 Compound”) that differs from pemetrexed only in its aryl region—the ’608 Compound contains a five-member thiophene ring in place of pemetrexed’s six-member benzene ring. 3 3 The parties use the expressions “thienyl group” and “phenyl group”; accordingly, we will also. ELI LILLY v. APP PHARMA 8 The ’608 Compound U.S. Patent 5,248,775 (the “’775 patent”) issued on September 28, 1993, from an application filed January 31, 1992, as a continuation-in-part of the application that led to the ’932 patent. The ’775 patent discloses a family of chemical intermediates that can be used to make a variety of antifolates, including pemetrexed, that contain a pyrrolo[2,3-d]pyrimidine bicyclic core. Among others, the ’775 patent claims a compound (the “’775 Intermediate”) that is used as an intermediate in one method for making pemetrexed. The ’775 Intermediate differs from pemetrexed in having a carbon-carbon triple bond in its bridge region and three protecting groups at substituent positions in its core and glutamate domains. 4 In addition, 4 Protecting groups are selectively reversible chemical modifications often used to prevent unwanted side reactions during multistep organic syntheses. In general, protecting groups are introduced at one or more particularly reactive positions in a complex molecule to stabilize or “protect” those parts of the molecule during later chemical manipulation of other target sites. Once a desired modification has been achieved elsewhere in the molecule, the protecting groups can be removed to reconstitute a reactive substituent at each protected position. The ’775 Intermediate contains a pivaloyl protecting group (denoted “t-BuCO”) in its core region and two methyl ester protecting groups (denoted “OMe”) in its glutamate domain. 9 ELI LILLY v. APP PHARMA Examples 6 and 10 of the ’775 patent disclose reduction and hydrolysis reactions, respectively, that could together be used to derive pemetrexed from the ’775 Intermediate. ’775 patent col. 9, l. 59 – col. 10, l. 5; col. 12, ll. 51–66. The ’775 Intermediate The ’932, ’608, and ’775 patents were assigned to the Trustees of Princeton University and exclusively licensed to Eli Lilly. The ’608 and ’775 patents have expired, but the ’932 patent remains in effect until July 24, 2016, due to a patent term extension of over four years to compensate for delays in the regulatory approval of Alimta®. See 35 U.S.C. § 156. Lilly holds a further six months of market exclusivity over pemetrexed pursuant to 21 U.S.C. § 355a.