United States Patent 12,083,182 (CNP agonist controlled release) : Scope, Claim Strength, and Landscape
United States Patent 12,083,182 is directed to methods for treating or delaying diseases amenable to CNP agonists using a controlled-release CNP agonist conjugate: a CNP moiety (-D) with a specific ring peptide sequence (SEQ ID NO:96) and a reversible prodrug linker that is cleavable under aqueous buffer at pH 7.4 and 37°C without enzymes, followed by polymer conjugation via a water-soluble branched polymer (≥10 kDa). Claim scope is anchored to (i) the exact structural identity and modifications of the CNP “ring moiety,” (ii) polymer/release architecture, and (iii) quantified in vitro performance metrics (NEP degradation half-life ratios and release half-life targets).
The claims you provided appear to be part of the issued patent text, with method claims (treatment/control/delay/prevention) reciting a precise conjugate structure and functional release/degradation performance. The most enforceable boundaries are the claim’s SEQ ID NO:96 ring identity, the reversible prodrug linker cleavable under defined conditions, and the NEP degradation half-life superiority of the controlled-release conjugate versus the corresponding released moiety (D-H).
What is the core claim construction in US 12,083,182?
Claim 1 sets the invention perimeter
Claim 1 (method of treating/controlling/delaying/preventing) requires administration of:
- A therapeutically effective amount of a controlled-release CNP agonist comprising:
- CNP moiety (-D) that includes a ring moiety having:
- the amino acid sequence of SEQ ID NO:96, with permission to modify:
- “methionine at position 11 of SEQ ID NO:96 can be substituted with asparagine”
- Ring architecture:
- “between two cysteine residues forming a disulfide bridge”
- Conjugation/release design:
- the ring moiety is “conjugated to a polymer via a reversible prodrug linker”
- linker is “cleavable in aqueous buffer at pH 7.4 and 37°C in the absence of enzymes”
- linker has a half-life “of up to six months”
- Polymer constraints:
- polymer is “water-soluble”
- polymer is “a branched polymer of at least 10 kDa”
- Release outcome:
- on cleavage, releases the CNP moiety in free form: D-H
- Functional degradation performance (NEP degradation assay):
- controlled-release conjugate has an at least 5-fold longer degradation half-life in vitro in a NEP degradation assay vs the corresponding released D-H
This combination is unusual in method patents because it binds treatment methods to (a) exact structural features and (b) quantitative in vitro biochemical outcomes.
How do dependent claims narrow the scope?
Claims 2–3: escalation of NEP resistance requirement
- Claim 2: controlled-release CNP agonist has ≥15-fold longer degradation half-life vs D-H in vitro NEP assay
- Claim 3: controlled-release CNP agonist has ≥25-fold longer degradation half-life vs D-H in vitro NEP assay
Practical effect: these claims create a graded “performance moat.” A competitor’s conjugate must hit the relevant threshold to fall inside each dependent claim (unless it independently satisfies Claim 1 and another dependent clause is not required).
Claims 4–7: release half-life gates at pH 7.4/37°C
Each requires release of D-H under “aqueous buffer at pH 7.4 and 37°C” with defined half-lives:
- Claim 4: ≥6 hours
- Claim 5: ≥24 hours
- Claim 6: ≥48 hours
- Claim 7: ≥168 hours (7 days)
Practical effect: these are time-based functional limitations. They restrict controlled-release kinetics, not just release presence.
What diseases are explicitly covered (claims 8–10)?
Claim 8: large basket of CNP-amenable skeletal and growth disorders
Includes, among others:
- Achondroplasia / hypochondroplasia / short stature / dwarfism
- Osteochondrodysplasia group (including thanatophoric dysplasia, osteogenesis imperfecta, achondrogenesis, chondrodysplasia punctata and derivatives)
- Various rhizomelic/mesomelic dysplasias
- Neurocristopathies and syndromes (e.g., LEOPARD, Noonan, Costello, Robinow, Reinhardt)
- SHOX deficiency, idiopathic short stature, and growth hormone deficiency
- Osteoarthritis and multiple craniofacial/skeletal morphologies
- Osteopetrosis and osteopoikilosis
Claim 9: additional craniosynostosis/FGF-R pathway craniofacial syndromes
- Muenke syndrome
- Crouzon syndrome
- Apert syndrome
- Jackson-Weiss syndrome
- Pfeiffer syndrome
- Crouzonodermoskeletal syndrome
Claim 10: single disease dependent
Practical effect: disease scope is broad and includes both monogenic growth disorders and selected syndromic indications. However, enforceability against a specific product will still hinge on meeting the conjugate/release/degradation limitations.
What structural claim elements are explicitly recited (claims 11–13)?
Claim 11: polymer size
- polymer is at least 30 kDa (dependent on Claim 1’s ≥10 kDa baseline)
Claim 12: formula-based definition of the controlled-release CNP agonist
Controlled-release conjugate is defined as:
- ZL2-L1-D) x (Ia), or a pharmaceutically acceptable salt
Where:
- -D is the CNP moiety
- -L1- is a reversible prodrug linker moiety
- -L2- is a single chemical bond or spacer
- -Z is a water-soluble and branched polymer moiety of at least 10 kDa
- x is an integer 1 through 16
Practical effect: this ties the invention to a multivalent architecture (x copies), and to a polymer conjugate whose identity is captured by “Z” formula details in Claim 13.
Claim 13: detailed polymer moiety definition
Claim 13 specifies the polymer moiety as formula (g) and includes extensive substituent possibilities:
- attachment points, alkyl/alkenyl/alkynyl chains (C1–50 alkyl; C2–50 alkenyl; C2–50 alkynyl)
- optional substitution set (halogens, CN, nitro, carboxylate/esters, amides, sulfonamides, etc.)
- aromatic/heteroaromatic segment options for -T-
- branching point options BPa from -N<, -CR<, >C<
- parameter a dependent on branching point
- bonding/spacing flexibility and polymeric moieties -Pa′/Pa″/-Pa′″
Practical effect: Claim 13 reads like a broad genus within constrained architecture: branched, water-soluble polymeric Z moiety, with permissible substitutions and backbone/spacer types. For litigation scope, this pushes the fight toward whether an accused product’s polymer backbone falls inside or outside the recited “g” formula and substituent sets, and whether the conjugation/release/degradation meet the functional limitations in Claim 1.
How do formulation/combo claims alter infringement pathways (claims 14–15)?
Claim 14: tyrosine kinase inhibitor combination
- controlled-release CNP agonist administered with “a tyrosine kinase inhibitor”
Claim 15: NVP-BGJ398 addition
- controlled-release CNP agonist administered with NVP-BGJ398
Practical effect: these introduce combinational method claims. A competitor pursuing combination therapy must still satisfy the CNP conjugate limitations plus the added agent. For portfolio strategy, these claims can be leveraged if a sponsor supports co-administration or combination study designs.
Scope reality check: what is actually protected?
Patent 12,083,182 protects methods of treating using a specific controlled-release CNP agonist conjugate. It does not appear limited to one dosing regimen, one patient genotype, or one formulation vehicle beyond the conjugate architecture and the functional release/degradation requirements.
The critical “tripwires” that likely govern design-around and litigation outcomes:
- SEQ ID NO:96 ring identity with only one permitted substitution:
- Met11 → Asn (no other sequence changes are expressly allowed in the claim text you provided)
- Disulfide bridge architecture: “between two cysteine residues forming a disulfide bridge”
- Reversible prodrug linker cleavable without enzymes at pH 7.4 / 37°C
- Controlled-release duration / half-life:
- “up to six months” for linker half-life
- and dependent claims with release half-life minimums up to 168 hours
- Branched, water-soluble polymer size:
- ≥10 kDa in Claim 1
- ≥30 kDa in Claim 11
- Quantitative NEP protection:
- ≥5-fold, ≥15-fold, or ≥25-fold longer NEP degradation half-life vs released D-H
Bottom line: even if a competitor uses CNP agonism, they can fall outside the claims by missing any of these constrained elements.
Patent landscape implications (what this blocks and where design-around pressure shifts)
1) This patent positions NEP stability as the differentiator
The claims are built around NEP degradation half-life superiority measured in vitro. That makes the “product” in legal terms the conjugate that provides measurable NEP resistance.
- If another sponsor’s CNP prodrug conjugate releases D-H under similar pH/temperature but does not improve NEP degradation half-life by the required factor, it may not meet Claim 1/2/3.
- If another sponsor provides NEP stability via a different mechanism (e.g., different enzyme inhibition or different stabilization not tied to the reversible prodrug linker architecture), they must still meet the conjugate requirements.
2) The polymer genus is broad, but constrained by the Z-g formula framework
Claim 13 contains extensive polymer backbone and substituent variability, which makes the invention’s structural scope relatively wide inside the defined genus.
However, enforcement will still depend on whether the accused polymer:
- qualifies as “water-soluble and branched”
- meets molecular weight (≥10 kDa or ≥30 kDa depending on the dependent claim)
- falls within formula (g) and substitution constraints
Design-around pressure: the shortest path is often to shift polymer chemistry outside the formula-defined genus or to alter the linker/release mechanism so that the conjugate does not satisfy “reversible prodrug linker cleavable … in absence of enzymes” or does not meet the NEP half-life ratio.
3) The ring moiety sequence and the allowed Met11 substitution are the most direct sequence constraints
The claim explicitly ties the ring moiety to SEQ ID NO:96 and only permits Met11 substitution with Asn.
Design-around pressure: altering the CNP ring identity outside that sequence (or changing the cysteine/disulfide arrangement) likely takes the product outside the claim, but whether it still provides therapeutic function depends on the biological role of that moiety.
4) Timing gates are another enforceability lever
Release half-life thresholds (6h, 24h, 48h, 168h) give measurable checkpoints. Competitors aiming for faster release could reduce risk of meeting dependent claim coverage.
How strong are the claims against typical CNP prodrug conjugate approaches?
Strength factors
- Quantitative in vitro assays (NEP degradation half-life fold changes) reduce “equivalence” arguments because thresholds define pass/fail.
- Sequence identity (SEQ ID NO:96) narrows to a defined peptide ring structure.
- Release conditions and absence of enzymes narrows to a specific prodrug mechanism claim.
Potential vulnerability points
- If a competitor disputes what “corresponding D-H” means experimentally, or differs in assay conditions, they could challenge whether their conjugate meets the fold-change thresholds.
- Polymer formula breadth (Claim 13) helps the patentee, but also invites interpretation fights over whether substituent/backbone choices fall within the formula.
Actionable takeaways for R&D and investment
Where to focus if you are designing an alternative
- Decide early whether your approach is built on the same ring moiety identity (SEQ ID NO:96) and Met11 → Asn allowance.
- Map your linker to the claim’s “reversible prodrug linker” behavior at pH 7.4/37°C without enzymes, and quantify release half-life against the dependent claim tiers.
- Generate NEP degradation half-life data for both:
- the controlled-release conjugate
- the “corresponding released D-H”
- Ensure your polymer meets or avoids:
- branched, water-soluble, ≥10 kDa or ≥30 kDa
- formula constraints of the “g” polymer moiety.
Where to focus if you are licensing or investing
- Evaluate whether the candidate’s mechanism targets NEP degradation protection with the required fold-increase.
- Track disease strategy: the claims include achondroplasia and a broad list of CNP-amenable skeletal and syndromic disorders, including Muenke/Crouzon/Apert/Pfeiffer and related craniosynostosis syndromes.
- For combination strategies, confirm whether co-administered agents include:
- “a tyrosine kinase inhibitor”
- specifically NVP-BGJ398, as Claim 15 names it.
Key Takeaways
- US 12,083,182 protects method-of-treatment uses of a controlled-release CNP agonist conjugate with a SEQ ID NO:96 ring moiety (Met11 may be replaced by Asn), disulfide bridge ring, enzyme-free reversible prodrug linker cleavage at pH 7.4/37°C, and a water-soluble branched polymer (≥10 kDa; ≥30 kDa in Claim 11).
- The patent is anchored by quantitative NEP degradation performance: ≥5-fold (Claim 1), with dependent thresholds of ≥15-fold and ≥25-fold.
- Additional enforceability levers include release half-life tiers up to ≥168 hours and explicit disease coverage including achondroplasia.
- Claims 14–15 extend coverage to combination administration, including NVP-BGJ398.
FAQs
1) Does the patent protect any use of CNP agonists?
No. It protects methods that administer a specific controlled-release CNP agonist conjugate with the claimed ring moiety, linker, polymer architecture, and assay-defined NEP degradation improvement.
2) What is the most important limiter in Claim 1?
The combination of SEQ ID NO:96 ring identity (with only Met11 to Asn permitted) plus the NEP degradation half-life fold improvement over the corresponding released D-H.
3) How can a product fall outside even if it releases D-H?
If the conjugate does not achieve the required NEP degradation half-life fold increase versus D-H, or if it fails the claim’s enzyme-free prodrug cleavage conditions and/or polymer constraints.
4) Are polymer variations likely to avoid infringement?
A competitor can attempt to avoid by changing polymer chemistry outside the formula (g) genus, but Claim 13 is broad. The safer design-around path is usually to alter sequence/linker release mechanism or fail the assay thresholds.
5) Do the dependent release half-life claims require exactly one release profile?
They require meeting the minimum release half-life thresholds (6h/24h/48h/168h) for D-H release at pH 7.4 and 37°C in aqueous buffer.
References
[1] United States Patent No. 12,083,182 (claim text provided by user).
