US Patent 11,369,590: Scope, Claims, Exclusivity and PSMA Radiopharmaceutical Patent Landscape

US Patent 11,369,590 protects a genus of prostate-specific membrane antigen, or PSMA, radioligands that combine a di-amino-acid urea binding group, a nitrogen-containing linker of approximately seven to nine atoms, and a metal-radionuclide chelate. The claims expressly cover gallium-68 embodiments and imaging of PSMA-expressing or PSMA-overexpressing pathogenic cells.

The claim structure is broad enough to read on gallium-68 PSMA imaging agents with a Glu-urea-Lys binding motif, an amino-acid-derived linker, and a chelator such as HBED-CC. It does not, however, expressly claim a particular named commercial product, specific chelator, manufacturing process, radiolabeling method, dosage, or treatment method.

What does US Patent 11,369,590 claim?

The patent has four principal independent claim categories:

Claim category	Independent claims	Protected subject matter
Radiolabeled compounds	1	B-L-D compounds or salts
Pharmaceutical compositions	13	B-L-D compounds with carriers, diluents or excipients
Imaging methods using compounds	25	Administration for imaging PSMA-associated tissue or cells
Imaging methods using compositions	27	Administration of a pharmaceutical composition for PSMA imaging

The central structural formula is B-L-D:

B is a urea formed from two amino acids.
L contains a divalent alkylenecarbonyl and at least one nitrogen atom.
L has a length of approximately seven to nine atoms.
D contains a metal radionuclide coordinated to a chelating group.
The radionuclide may be gallium-68.
The compound may be administered as a salt or in an aqueous pharmaceutical composition.

Claims 2 and 15 narrow B by requiring a particular amino-acid-derived structure in which R1 is hydrogen and R2 is a substituted carboxylic acid covalently attached to L. Claims 3, 4, 8, 9, 21, 22, 23 and 24 impose amide-bond limitations.

How broad is the composition-of-matter claim?

Claim 1 is the principal composition-of-matter claim. Its breadth comes from the use of functional definitions rather than a single chemical structure.

B: the PSMA-binding urea domain

The B group is defined as a urea of two amino acids. In practical terms, this language is directed to the well-established PSMA-binding pharmacophore based on amino-acid-derived urea compounds, particularly glutamate-urea-lysine or closely related analogues.

The claim does not limit B to one stereochemical configuration in the text supplied. It also does not expressly require the exact Glu-urea-Lys structure commonly used in PSMA ligands. The dependent claims narrow B toward a specific substituted carboxylic-acid configuration.

This creates two infringement questions:

Whether the accused ligand contains a urea structurally derived from two amino acids.
Whether the amino-acid substituents fall within the construction of R1, R2 and the substituted carboxylic-acid language in claim 2.

A commercial ligand with a different PSMA-binding scaffold, such as a non-urea inhibitor or a peptidomimetic structure, has a stronger non-infringement position against claim 1.

L: the seven-to-nine-atom linker

L must include:

a divalent alkylenecarbonyl;
at least one nitrogen atom; and
an overall length of approximately seven to nine atoms.

The claim also permits a wide range of substituents, including alkyl, alkoxy, hydroxy, amino, halo, aryl, heteroaryl, carboxy and related groups.

This is a meaningful scope limitation. A linker that is too short, too long, lacks the required nitrogen atom, or does not contain the required divalent alkylenecarbonyl may fall outside claim 1. The claim does not appear to require one specific linker sequence, one specific amino acid, or one specific chelator.

The approximately seven-to-nine-atom limitation is likely to become central in claim construction and validity disputes. The parties would need to define:

the atoms included in the length calculation;
whether heteroatoms count in the same manner as carbon atoms;
whether the count follows the shortest covalent path between B and D;
whether linker atoms incorporated into amide bonds are included; and
how branching and substituents affect the count.

The phrase “about” increases the interpretive range but does not eliminate the need for a measurable boundary.

D: the radiometal-chelate domain

D includes a radioactive metal isotope coordinated to a chelating group. Claim 1 therefore reaches a platform rather than one radionuclide.

Claim 5 expressly narrows the radioactive isotope to gallium-68. The claim set does not identify the chelator by name. That omission is commercially important because it leaves the independent claim potentially applicable to multiple gallium-68 chelation systems, subject to the other structural limitations.

The claims also use the broader phrase “radioactive isotope of a metal.” On their face, the independent claims can extend beyond gallium-68 to other radiometals, provided the B-L-D structure and linker limitations are met. Examples potentially relevant to the claim language include lutetium-177, actinium-225, copper-64 and zirconium-89, although each product requires a separate structural analysis.

Which claims cover gallium-68 PSMA imaging agents?

Claims 5 through 12, 17 through 24, 26 and 28 through 30 expressly identify gallium-68 or depend from claims that do.

The principal gallium-68 coverage is:

Claim	Gallium-68 scope
5	Compound of claim 1 with gallium-68
6	Claim 3 amide-bond embodiment with gallium-68
7	Claim 4 amide-bond embodiment with gallium-68
8-12	B limitation, amide bonds and gallium-68
17-24	Pharmaceutical composition embodiments with gallium-68
26	Compound-based PSMA imaging method with gallium-68
28-30	Composition-based PSMA imaging method with gallium-68

The likely commercial relevance is gallium-68 gozetotide, also known as gallium-68 PSMA-11. FDA approved the product as Illuccix in 2021 and as Locametz in 2022 for PSMA PET imaging in prostate cancer. [2,3]

A product-by-product infringement analysis still requires the exact chemical structure, linker atom count, chelator identity, salt form and labeling configuration. A product name alone does not resolve those issues.

What formulations are protected by US 11,369,590?

Claims 13 through 24 cover pharmaceutical compositions containing the claimed B-L-D compound and one or more carriers, diluents or excipients.

Claim 14 narrows the carrier to an aqueous solution. Claims 16 and 18 through 24 carry the aqueous-solution and gallium-68 limitations into narrower combinations.

The formulation claims are relatively conventional. They do not require:

a specific buffer;
a specific pH;
a particular stabilizer;
a specified radionuclide concentration;
a defined radiochemical purity;
a kit configuration;
a particular container;
a shelf-life period; or
a specific administration route.

The practical value of claims 13 through 24 depends on whether the accused product contains the claimed radioligand in a composition that meets the B, L and D limitations. An aqueous injectable formulation may satisfy the carrier limitation, but the carrier alone is not sufficient for infringement.

What methods of use are protected?

Claims 25 and 27 are method claims directed to imaging tissue or cells associated with pathogenic populations that express or overexpress PSMA.

The claims do not limit the method to prostate cancer. The phrase “pathogenic populations of cells” could encompass malignant or otherwise disease-associated PSMA-expressing cells, subject to the written description and claim-construction record.

The claims also do not expressly limit:

PET versus another imaging modality;
intravenous versus another route of administration;
a particular patient population;
a particular dose;
a particular imaging time;
a specific organ;
a specific disease stage; or
a particular image interpretation protocol.

The use of gallium-68 in claims 26 and 28-30 makes the claims particularly relevant to PSMA PET products. A product label that directs administration of a covered gallium-68 compound for PSMA imaging would create the strongest method-of-use exposure.

Does the patent cover PSMA-11?

PSMA-11 is commonly described as a glutamate-urea-lysine PSMA ligand linked through an aminohexanoic-acid spacer to the HBED-CC chelator and labeled with gallium-68. It is the active imaging agent associated with Illuccix and Locametz. [2,3]

The supplied claim language appears directed to the same general architecture:

PSMA-11 characteristic	Relevance to US 11,369,590
Urea of two amino acids	Corresponds to B
Amino-acid-derived spacer	Potentially corresponds to L
Nitrogen-containing linker	Expressly required by claim 1
Gallium-68	Expressly claimed in dependent claims
HBED-CC-type chelation	Potentially corresponds to D
PSMA imaging	Expressly claimed in claims 25 and 27

Whether PSMA-11 falls within a particular claim depends on the patent’s construction of “about 7 to about 9 atoms in length,” the precise B structure, and the connection points used to count L. The claim set is sufficiently close to the PSMA-11 architecture to make the patent relevant to gallium-68 PSMA-11 products.

How does the patent compare with PSMA-617 patent protection?

PSMA-617 is a different commercial architecture. It is generally associated with a glutamate-urea-lysine PSMA-binding group, a longer linker and a DOTA chelator. It is used primarily with lutetium-177 and is also being studied with actinium-225.

Issue	US 11,369,590	PSMA-617-related technology
Primary use	Diagnostic PSMA imaging	Radioligand therapy and theranostics
Express radionuclide	Gallium-68 in dependent claims	Commonly lutetium-177 or actinium-225
Chelator	Functional chelator definition	DOTA-centered technology
Linker	Approximately seven to nine atoms	Often longer and structurally distinct
Method claims	Imaging	Treatment, imaging or theranostic use
Main commercial products	Gallium-68 PSMA PET agents	Pluvicto and related radioligand products

PSMA-617 may avoid some claims if its linker does not satisfy the seven-to-nine-atom limitation or if its specific structure falls outside the claimed linker architecture. The broad radiometal language in claim 1 creates a possible overlap analysis for non-gallium radionuclides, but the structural limitations remain controlling.

Novartis’ Pluvicto is a lutetium-177 PSMA-directed product approved by FDA for certain patients with PSMA-positive metastatic castration-resistant prostate cancer. Its regulatory and patent position is separate from the gallium-68 diagnostic products. [4]

What is the FDA regulatory and Orange Book status?

Gallium-68 PSMA products have received FDA authorization through drug-approval pathways rather than through a generic abbreviated new drug application pathway.

Product	Active imaging agent	FDA status
Illuccix	Gallium-68 gozetotide	Approved for PSMA PET imaging
Locametz	Gallium-68 gozetotide	Approved kit for preparation of gallium-68 gozetotide injection
Pluvicto	Lutetium-177 vipivotide tetraxetan	Approved PSMA-directed radioligand therapy

The Orange Book is principally relevant to approved drug products and listed patents submitted by the NDA holder. [5] A patent’s existence does not establish that it is listed in the Orange Book. Patent 11,369,590 must be matched against the relevant NDA, product presentation and FDA listing record before it can be treated as an Orange Book-listed patent.

For radiopharmaceutical competitors, the practical exclusivity analysis also includes:

FDA regulatory exclusivity;
drug-substance and drug-product manufacturing controls;
radionuclide supply;
radiolabeling infrastructure;
hospital pharmacy requirements;
state and federal radioactive-material licenses; and
product-specific patent and license rights.

When does US Patent 11,369,590 lose exclusivity?

US 11,369,590 issued on June 28, 2022. Patent expiration is generally calculated as 20 years from the earliest effective nonprovisional U.S. filing date, subject to patent-term adjustment, patent-term extension, terminal disclaimers and any applicable disclaimer record. [1]

The issue date is not the expiration date. A reliable exclusivity date requires the patent’s earliest priority chain, PTA certificate, PTE status and terminal-disclaimer information. The patent number and claim text alone do not establish the final expiration date.

For commercial diligence, the relevant date should be recorded as:

the base patent-term date;
the USPTO-adjusted expiration date;
any FDA patent-term extension;
any terminal disclaimer; and
any later-issued continuation or divisional patents with separate claim scope.

Are there Paragraph IV risks?

A generic applicant could challenge the patent through an ANDA Paragraph IV certification if the relevant patent is listed for an FDA-approved product and the proposed product is alleged not to infringe, or the patent is alleged to be invalid or unenforceable. [6]

The most credible Paragraph IV positions would focus on:

lack of anticipation for the claimed linker geometry;
obviousness based on earlier PSMA urea ligands and known chelators;
indefiniteness of “about 7 to about 9 atoms in length”;
written-description support for the breadth of the B-L-D genus;
enablement across multiple radiometals and chelators;
lack of infringement because the proposed ligand uses a different linker length;
lack of infringement because the B group is not a urea of two amino acids; and
lack of infringement by a product using a different chelation architecture.

The patent holder would likely rely on the specific combination of PSMA-binding urea, linker topology, linker length and radiometal-chelate function. Prior art directed separately to PSMA ligands, chelators or radiometals would not necessarily anticipate the complete combination.

Which companies are challenging the patent?

The supplied information does not establish a public Paragraph IV filing, ANDA litigation, inter partes review, district-court action or settlement involving US 11,369,590. Patent litigation databases and USPTO records should be checked for the specific patent number and related family members before assigning a challenger or litigation status.

The competitive parties most relevant to the surrounding market include:

Telix Pharmaceuticals, associated with Illuccix;
Novartis, associated with Locametz and Pluvicto;
Lantheus, a major PSMA imaging and radiopharmaceutical company;
Blue Earth Diagnostics, associated with fluorinated PSMA imaging products;
Curium and other radiopharmaceutical manufacturers;
academic institutions and licensees developing PSMA ligands; and
generic or hospital-based radiopharmacy suppliers.

Market participation does not establish infringement or a patent challenge.

How strong is the patent estate?

The claim set has moderate platform breadth and stronger relevance to gallium-68 PSMA imaging than to all radiometal products.

Strength	Assessment
Composition coverage	Broad functional genus, but constrained by B and L structure
Gallium-68 coverage	Direct and commercially relevant
Chelator coverage	Broad because no single chelator is required
Formulation coverage	Narrower and conventional
Imaging-use coverage	Broad disease and imaging language
Manufacturing coverage	No express process claims in the supplied set
Validity risk	Concentrated in obviousness, enablement and linker-length construction
Design-around potential	Meaningful through alternate PSMA scaffolds, linkers or chelators
Commercial relevance	Highest for gallium-68 PSMA urea ligands

The absence of manufacturing claims limits the patent’s ability to block an alternative synthesis or radiolabeling process when the resulting product does not fall within the composition claims. The absence of treatment claims also limits the patent’s direct reach into therapeutic radioligands unless the therapeutic compound independently satisfies the composition claims.

What generic launch scenarios exist?

A competing gallium-68 PSMA product could pursue several strategies:

Use the same or substantially similar PSMA-11 structure and challenge the patent through Paragraph IV.
Use a different PSMA-binding scaffold that is not a urea of two amino acids.
Retain the urea pharmacophore but alter linker length outside the construed seven-to-nine-atom range.
Use a different linker lacking the required divalent alkylenecarbonyl.
Use a different chelator and assess whether D remains within the functional claim.
Develop a fluorine-18 PSMA agent with a non-metal radionuclide, avoiding the radiometal limitation.
Supply a radiopharmacy preparation that does not practice the claimed composition or method.

The strongest design-around route is usually a change to the B-L-D architecture rather than a simple substitution of buffer, salt, vial, or excipient.

Key Takeaways

US 11,369,590 claims B-L-D PSMA radioligands, compositions and imaging methods.
The core structure combines a urea of two amino acids, a nitrogen-containing seven-to-nine-atom linker and a radiometal chelate.
Gallium-68 is expressly covered in multiple dependent claims.
The patent is highly relevant to gallium-68 PSMA-11-type imaging products.
The claims do not expressly require HBED-CC, PSMA-11, a particular dose, a particular buffer or a manufacturing process.
PSMA-617 and other therapeutic radioligands require separate linker and chelator analysis.
The principal validity pressure points are obviousness, enablement, written description and the meaning of “about 7 to about 9 atoms in length.”
The final expiration date cannot be determined from the issue date alone.
No litigation or Paragraph IV challenge is established by the supplied record.
The commercial risk is greatest for products using the same amino-acid urea, linker architecture and gallium-68 chelation design.

FAQs

Does US 11,369,590 cover all gallium-68 PSMA tracers?

No. The tracer must satisfy the claimed amino-acid urea, linker and radiometal-chelate limitations. Gallium-68 alone is insufficient.

Does the patent cover fluorine-18 PSMA imaging agents?

Generally, the supplied claims require a radioactive isotope of a metal. A fluorine-18 compound would ordinarily not satisfy that limitation, although its separate patent position requires independent analysis.

Does the patent cover lutetium-177 PSMA therapy?

Potentially, if the lutetium-177 compound satisfies the B-L-D and linker limitations. The patent does not limit all embodiments to gallium-68, but it contains no express therapeutic-method claims in the supplied claim set.

Can a different chelator avoid infringement?

Possibly, but not automatically. D is defined functionally as a radioactive metal coordinated to a chelating group. A different chelator may remain within claim 1 if the rest of the claimed structure is present.

Is an aqueous gallium-68 PSMA injection automatically covered by claims 13 and 14?

No. The product must first contain a compound that satisfies claim 1. The aqueous carrier limitation is an additional requirement, not a substitute for the compound limitations.

Sources:

United States Patent and Trademark Office. (2022). U.S. Patent No. 11,369,590, patent records and claims.
U.S. Food and Drug Administration. (2021). Illuccix prescribing information.
U.S. Food and Drug Administration. (2022). Locametz prescribing information.
U.S. Food and Drug Administration. (2022). Pluvicto prescribing information.
U.S. Food and Drug Administration. (2024). Approved drug products with therapeutic equivalence evaluations.
U.S. Food and Drug Administration. (2017). Approved drug products and therapeutic equivalence evaluations, guidance on patent certifications and exclusivity.

Applicant	Tradename	Generic Name	Dosage	NDA	Approval Date	TE	Type	RLD	RS	Patent No.	Patent Expiration	Product	Substance	Delist Req.	Patented / Exclusive Use	Submissiondate
Novartis	LOCAMETZ	gallium ga-68 gozetotide	POWDER;INTRAVENOUS	215841-001	Mar 23, 2022		RX	Yes	Yes	⤷ Start Trial	⤷ Start Trial	Y	Y		FOR USE AFTER RADIOLABELING WITH GALLIUM-68, FOR POSITRON EMISSION TOMOGRAPHY OF PROSTATE-SPECIFIC MEMBRANE ANTIGEN (PSMA)-POSITIVE LESIONS IN MEN WITH PROSTATE CANCER	⤷ Start Trial
>Applicant	>Tradename	>Generic Name	>Dosage	>NDA	>Approval Date	>TE	>Type	>RLD	>RS	>Patent No.	>Patent Expiration	>Product	>Substance	>Delist Req.	>Patented / Exclusive Use	>Submissiondate

Country	Patent Number	Estimated Expiration	Supplementary Protection Certificate	SPC Country	SPC Expiration
Australia	2008289108	⤷ Start Trial
Canada	2696627	⤷ Start Trial
China	102014956	⤷ Start Trial
China	104873982	⤷ Start Trial
Denmark	2187965	⤷ Start Trial
>Country	>Patent Number	>Estimated Expiration	>Supplementary Protection Certificate	>SPC Country	>SPC Expiration

Details for Patent: 11,369,590

Which drugs does patent 11,369,590 protect, and when does it expire?

Summary for Patent: 11,369,590