ITM ISoTope Technologies Munich Se v. Johns Hopkins University

1. Case Identification

• Case #: PGR2025-00065
• Patent #: 12,115,233
• Filed: July 15, 2025
• Petitioner(s): ITM Isotope Technologies Munich SE
• Patent Owner(s): The Johns Hopkins University
• Challenged Claims: 1-4

2. Patent Overview

• Title: Low Molecular Weight Compounds for Imaging and Radiotherapeutics
• Brief Description: The ’233 patent discloses low molecular weight compounds for diagnostic imaging and radiotherapy. The compounds have a general formula B-L-A, where A is a moiety targeting fibroblast-activation protein-α (FAP-α), B is an optical or radiolabeled functional group, and L is a linker connecting A and B.

3. Grounds for Unpatentability

Ground 1: Claims 1-4 are obvious over Jansen I and/or Jansen II in view of Zimmerman and Pomper

• Prior Art Relied Upon: Jansen I (Patent 9,346,814), Jansen II (a 2013 journal article), Zimmerman (Application # 2010/0098633), and Pomper (Application # 2012/0009121).
• Core Argument for this Ground:
  • Prior Art Mapping: Petitioner argued that the claimed FAP-α targeting moiety (A) was expressly disclosed in Jansen I and Jansen II, which teach 4-quinolinoyl-based FAP inhibitors for their high affinity and selectivity. Zimmerman disclosed the remaining components: radiolabeled functional groups (B) suitable for imaging and radiotherapy, and bifunctional linkers (L) to attach them to FAP inhibitors. Pomper also taught attaching imaging agents to inhibitors via linkers. The specific limitations of dependent claims 2-4, such as the R3x group being -CN, were also disclosed in the exemplary compounds of Jansen I and Jansen II.
  • Motivation to Combine: Petitioner asserted that a person of ordinary skill in the art (POSITA) would combine the high-affinity FAP inhibitor from Jansen I/II with the imaging/therapeutic modules and linkers from Zimmerman to create a targeted diagnostic or therapeutic agent. Pomper further motivated the combination by teaching the benefits of low molecular weight imaging agents, such as better tumor access and promise in preclinical studies, providing a clear reason to develop the claimed compounds.
  • Expectation of Success: A POSITA would have had a reasonable expectation of success because combining known targeting moieties with known imaging agents via known linkers was a well-established strategy in medicinal chemistry for creating targeted diagnostics and therapeutics.

Ground 2: Claims 1-4 are obvious over Dvořáková in view of Pomper

• Prior Art Relied Upon: Dvořáková (a 2017 journal article) and Pomper (Application # 2012/0009121).
• Core Argument for this Ground:
  • Prior Art Mapping: Petitioner contended that Dvořáková disclosed compounds having the full B-L-A structure, including the same FAP-α targeting moiety (A), a PEG linker (L), and an attached optical dye (B). However, Dvořáková’s compounds were high molecular weight polymer conjugates. The only limitation not explicitly met was the "low molecular weight" preamble of claim 1.
  • Motivation to Combine: A POSITA reading Dvořáková would have been motivated by Pomper to modify Dvořáková’s high molecular weight conjugate into a low molecular weight version. Pomper explicitly taught that low molecular weight agents have advantages over larger molecules, including improved pharmacokinetics and better tumor access. Dvořáková itself described its molecules as "highly module and versatile," suggesting to a POSITA that their components, including molecular weight, could be readily adjusted.
  • Expectation of Success: A POSITA would have reasonably expected success in creating a smaller, effective version of Dvořáková’s compound, as this represented a routine optimization to improve drug delivery properties as taught by Pomper.

Ground 3: Claims 1-4 lack enablement under 35 U.S.C. §112

• Core Argument for this Ground: Petitioner argued the claims fail to meet the enablement requirement under the framework of Amgen Inc. v. Sanofi. The claims recite a vast, functional genus for moieties B ("any... functional group suitable for" imaging/therapy) and L ("a linker having bifunctionalization adapted to form a chemical bond"). These functional limitations encompass a virtually infinite number of candidate structures. However, the specification provided only two working examples (XY-FAP-01 and XY-FAP-02) and offered no common structural features or "blaze marks" to guide a POSITA to identify which of the countless other possible compounds would work without undue experimentation. This lack of guidance, Petitioner asserted, amounted to a mere "research plan" that required a POSITA to engage in an iterative, trial-and-error screening process, which is not enablement.

• Additional Grounds: Petitioner asserted additional grounds that the claims lack written description (§112) for failing to show possession of the full genus, are indefinite (§112) because the term "low molecular weight" is undefined and relative, and that claim 1 is invalid for statutory double patenting under 35 U.S.C. §101 over claim 1 of the parent ’201 patent.

4. Key Claim Construction Positions

• "Low Molecular Weight": Petitioner argued this term is indefinite under §112. The specification provides no definition or numerical range. The range proposed during prosecution (50 to 1,500 Daltons) was based on unrelated art (metabolomics) and would improperly exclude fluorescent dye embodiments explicitly disclosed in the patent’s specification that have molecular weights greater than 1,500 Da by themselves. Therefore, the term lacks reasonable certainty and renders the claims indefinite.

5. Arguments Regarding Discretionary Denial

• Petitioner argued that discretionary denial would be inappropriate. There is no parallel litigation that would implicate Fintiv factors. Under the Advanced Bionics framework, Petitioner asserted that the Examiner committed material error by allowing the claims. The Examiner overlooked the teachings of Pomper regarding the benefits of low molecular weight agents and erroneously relied on a declaration of "unexpected results" that was not commensurate with the vast scope of the claims. Furthermore, the challenges under §112 (enablement, written description, indefiniteness) and §101 (double patenting) are new arguments never presented to or considered by the Office, counseling against denial under 35 U.S.C. §325(d).

6. Relief Requested

• Petitioner requests institution of Post Grant Review and cancellation of claims 1-4 as unpatentable.