Court Opinion

ID: 9839843
Source: CourtListenerOpinion
Date Created: 2023-09-14 15:01:49.631756+00
Date Added: 2024-06-11T09:41:35.578720
License: Public Domain

Case: 23-1540    Document: 35     Page: 1   Filed: 09/14/2023

        NOTE: This disposition is nonprecedential.

   United States Court of Appeals
       for the Federal Circuit
                  ______________________

        AZURITY PHARMACEUTICALS, INC.,
                Plaintiff-Appellant

                             v.

            ALKEM LABORATORIES LTD.,
                  Defendant-Appellee
                ______________________

                        2023-1540
                  ______________________

     Appeal from the United States District Court for the
 District of Delaware in No. 1:19-cv-02100-MSG, Judge
 Mitchell S. Goldberg.
                  ______________________

                Decided: September 14, 2023
                  ______________________

     TUNG ON KONG, Wilson, Sonsini, Goodrich & Rosati,
 PC, San Francisco, CA, argued for plaintiff-appellant. Also
 represented by WENDY L. DEVINE, KRISTINA M. HANSON;
 KELSEY CURTIS, RICHARD TORCZON, Washington, DC.

    TIMOTHY H. KRATZ, Kratz & Barry LLP, Atlanta, GA,
 argued for defendant-appellee.    Also represented by
 GEORGE BARRY, III; MICHAEL PATRICK HOGAN, Philadel-
 phia, PA; R. TOUHEY MYER, Wilmington, DE.
                 ______________________
Case: 23-1540     Document: 35     Page: 2    Filed: 09/14/2023

 2                          AZURITY PHARMACEUTICALS, INC. v.
                                   ALKEM LABORATORIES LTD.

      Before DYK, HUGHES, and STOLL, Circuit Judges.
 DYK, Circuit Judge.
      Azurity Pharmaceuticals, Inc. (“Azurity”) appeals a de-
 cision of the United States district court for the District of
 Delaware determining that claims 16, 18, 22, 23, and 28 of
 U.S. Patent No. 10,786,482 and claims 4, 7, 17, and 18 of
 U.S. Patent No. 10,918,621 were invalid. We affirm.
                        BACKGROUND
     The ’482 and ’621 patents claim liquid formulations of
 enalapril. Enalapril treats high blood pressure and has
 long been used in tablet form. Children and elderly pa-
 tients can have difficulty swallowing tablets, making the
 liquid form a useful alternative. The difficulty with a liquid
 form is that enalapril degrades in water. The ’482 and ’621
 patents aim to remedy this and claim a liquid formulation
 that “maintains about 95% w/w or greater of the initial en-
 alapril amount at the end of a storage period of at least 12
 months at about 5±3° C.” ’482 patent, col. 42 ll. 21–23.
     Alkem Laboratories, Ltd. (“Alkem”) submitted an Ab-
 breviated New Drug Application (“ANDA”). Azurity
 brought suit claiming the ANDA infringed the ’482 and
 ’621 patents. The district court agreed that the ANDA in-
 fringed, and that determination is not challenged on ap-
 peal. However, the district court also found the ’482 and
 ’621 patents were invalid due to obviousness and insuffi-
 cient written description. Azurity appeals.
                         DISCUSSION
     “Obviousness is a mixed question of fact and law.” No-
 vartis AG v. Torrent Pharms. Ltd., 853 F.3d 1316, 1327
 (Fed. Cir. 2017). The district court’s legal conclusion of ob-
 viousness is subject to de novo review, while “subsidiary
 factual findings are reviewed for substantial evidence.” Id.
 Substantial evidence is “such relevant evidence as a
Case: 23-1540    Document: 35       Page: 3   Filed: 09/14/2023

 AZURITY PHARMACEUTICALS, INC. v.                           3
 ALKEM LABORATORIES LTD.

 reasonable mind might accept as adequate to support a
 conclusion.” Consol. Edison Co. v. NLRB, 305 U.S. 197, 229
 (1938).
     We see no legal error in the district court’s obviousness
 determination and conclude that it was supported by sub-
 stantial evidence. Because we affirm the district court’s ob-
 viousness determination, we decline to reach the issue of
 written description.
                        AFFIRMED