Scope, claims, and US patent landscape for US Drug Patent 5,861,379
What does US 5,861,379 claim at the core?
US 5,861,379 is directed to chimeric fatty-body GRF (growth-hormone releasing factor) analogs with increased biological potency and to downstream pharmaceutical compositions and use methods (growth hormone release, diagnostic/prognostic response measurement, and multiple therapeutic indications).
Claim architecture (high level)
- Independent chemical scope: Claim 1 (core genus) and Claim 8 (one specific embodiment).
- Dependent chemical refinements: Claims 2-7 narrow the genus by fixing substituent parameters and the A30 tail sequence.
- Composition and method layer: Claims 9-17 cover:
- formulation (Claim 9)
- administration to increase GH (Claim 10)
- diagnostic testing via GH response (Claim 11)
- treatment and improvement indications, including pituitary dwarfism/growth retardation, wound/bone healing, osteoporosis, protein anabolism, lipolysis in obesity, and “overall upgrading” of somatroph function (Claims 12-17).
How broad is the chemical genus in Claim 1?
Claim 1 defines a chimeric fatty body GRF analog by:
- A peptide scaffold:
A1-A2-Asp-Ala-Ile-Phe-Thr-A8-Ser-Tyr-Arg-Lys-Val-Leu-A15-Gln-Leu-A18-Ala-Arg-Lys-Leu-Leu-A24-Asp-Ile-A27-A28-Arg-A30-R0
- Terminal residue:
R0 = NH2 (explicit in Claim 1 text).
- Variable substitutions at key positions:
- A1 = Tyr or His
- A2 = Val or Ala
- A8 = Asn or Ser
- A15 = Ala or Gly
- A18 = Ser or Thr
- A24 = Gln or His
- A27 = Met, Ile, or Nle (norleucine)
- A28 = Ser or Asp
- A30 = “any amino acid sequence of 1 to 15 residues”
- A1 anchoring modification with a hydrophobic tail via formula I:
- Claim 1 states A1 is N-anchored by a hydrophobic tail of the general formula I (structure given as ##STR6##).
- Formula I parameters constrain the tail’s chemistry and chain length:
- R1-R4 and R5-R6: hydrogen or small alkyl substituents
- heteroatoms allowed: oxygen or sulfur in multiple positions
- geometric isomerism: cis/trans (CH=CR5) and cis/trans (CH=CR6)
- key parameters a-h are restricted such that:
- a is 1; b is 0; c is 0 to 3; d is 0 or 1; e is 0 to 3; f is 0 or 1; g is 0 to 4; h is 0 to 1
- d + f = 1 or 2
- and the total atom-count constraint requires a linear main chain of between 5 and 7 carbon atoms.
What Claim 1 really covers in practice
Claim 1 is a two-part lock-and-key:
- Part A: the GRF peptide sequence pattern with a defined set of position-wise substitutions plus a free-ended A30 1 to 15 residue extension.
- Part B: the hydrophobic tail attached to N of A1, with structural parameter ranges that limit tail length and functionality rather than specifying a single compound.
This means the genus is not purely sequence-based. The hydrophobic tail constraints in formula I are central to scope and potency.
Which claim elements materially constrain design-around work?
In claim-coverage terms, three elements are most likely to control infringement risk:
-
N-anchoring of A1 by the hydrophobic tail (formula I)
If the hydrophobic modification is not N-anchored at the A1 position (or uses a tail not meeting formula I constraints), coverage falls apart.
-
The peptide region defined by the fixed backbone plus the allowed residue substitutions
Even with A30 freedom, the internal pattern:
- “Asp-Ala-Ile-Phe-Thr”
- “Ser-Tyr-Arg-Lys-Val-Leu”
- “Gln-Leu-A18-Ala-Arg-Lys-Leu-Leu-A24-Asp-Ile-A27-A28-Arg”
remains required.
-
Tail carbon count and sub-parameter sums
The requirement for a linear main chain of 5 to 7 carbon atoms plus the arithmetic constraints (notably d + f) acts as a claim gate against many alternative lipophilic groups.
How does Claim 8 narrow to a specific embodiment?
Claim 8 locks down one explicit hydrophobic GRF analog:
Claim 8 explicit structure (trans)
- transCH3—CH2—CH=CH—CH2—CO- attached to the CO- then Tyr ... peptide:
- peptide sequence after the “CO-” segment:
Tyr-Ala-Asp-Ala-Ile-Phe-Thr-Asn-Ser-Tyr-Arg-Lys-Val-Leu-Gly-Gln-Leu-Ser-Ala-Arg-Lys-Leu-Leu-Gln-Asp-Ile-Met-Ser-Arg-Gln-Gln-Gly-Glu-Ser-Asn-Gln-Glu-Arg-Gly-Ala-Arg-Ala-Ala-Arg-Leu-NH2
This gives a concrete “at-risk” molecule:
- A1 = Tyr
- A2 = Ala
- A8 = Asn
- A15 = Gly
- A18 = Ser
- A24 = Gln
- A27 = Met
- A28 = Ser
- R0 = NH2
- A30 corresponds to the tail segment implied by the C-terminal residues after Arg (with explicit sequence in the claim).
What do Claims 2-7 do to scope?
These are targeted refinements to the genus.
- Claim 2: sets c = 0.
- Claim 3: sets A30 to a specific 13-residue sequence:
Gln-Gln-Gly-Glu-Ser-Asn-Gln-Glu-Arg-Gly-Ala-Arg-Ala-Arg-Leu (as written)
- Claim 4: reiterates R0 = NH2.
- Claim 5: provides explicit compound forms:
- one entry for cis with a defined sequence and an “Asn” vs “AsH” replacement (the text reads “AsH” in the trans variant line as typed).
- one entry for trans with a matching peptide but a different substitution at the position corresponding to A8 and/or a specific residue detail.
- Claim 6: imposes multiple formula I parameter constraints:
- d + f = 2
- R1, R2, R3, R4 = hydrogen
- c + e + g = 2, 3, or 4
- Claim 7: alternative constraints:
- R1, R2, R3, R4 = hydrogen
- c + e + g = 3, 4, or 5
Practical implication
Claims 2-7 reduce the tail configuration space and/or lock the peptide A30 extension. They do not change the requirement that the analog must match the overall backbone and the N-anchored hydrophobic tail defined by formula I.
How do the downstream method claims expand the commercial threat surface?
Claims 9-17 convert the chemical entity into a broad medical and use-based portfolio.
Claim 9: formulation
- A pharmaceutical formulation for inducing growth hormone release:
- active ingredient: a GRF analog “as claimed in claims 1 or 8”
- plus pharmaceutically acceptable carrier/excipient/diluent.
Claim 10: GH elevation
- Method of increasing growth hormone in a patient by administering an effective amount of the claimed GRF analog.
Claim 11: diagnostic
- Method of diagnosing growth hormone deficiencies:
- administer the GRF analog
- measure growth hormone response.
Claims 12-17: therapeutic and metabolic uses
Each requires administration of an effective amount of a GRF analog meeting claims 1 or 8:
- Claim 12: pituitary dwarfism or growth retardation
- Claim 13: wound or bone healing
- Claim 14: osteoporosis
- Claim 15: improving protein anabolism (human or animal)
- Claim 16: inducing lipolytic effect in clinical obesity
- Claim 17: “overall upgrading of somatroph function” (human or animal)
Scope consequence
Even if the chemical structure is narrowly constrained, the use claims are wide. In litigation, a single infringement chemical match can attach to multiple indication-driven business models (diagnostic kits, GH-release therapeutics, metabolic and tissue repair programs).
Patent landscape analysis for US 5,861,379 (scope vs likely surrounding competitors)
A complete US patent landscape requires bibliographic and citation data (family, assignees, continuations, and cited references). The provided prompt includes only claim text; it does not include:
- patent application publication number, priority date, or assignee
- prosecution history identifiers
- list of cited documents
- related patents in the same family
- expiration/term adjustments and maintenance status
Without that, a defensible competitor map (other US patents and their claim coverage relative to this genus) cannot be produced.
Evidence-grade claim coverage matrix
Below is a practical mapping from the claim language to “must-have” and “optional/replaceable” features for design and freedom-to-operate analysis.
| Feature |
Where in claims |
Coverage rule (must/allowed) |
Typical design impact |
| GRF peptide backbone with fixed internal motifs |
Claim 1 |
Required scaffold: A1-A2-Asp-Ala-Ile-Phe-Thr-A8-Ser-Tyr-Arg-Lys-Val-Leu-A15-Gln-Leu-A18-Ala-Arg-Lys-Leu-Leu-A24-Asp-Ile-A27-A28-Arg-A30-R0 |
Must preserve backbone and positioning of allowed substitutions |
| A1 allowed |
Claim 1 |
Tyr or His |
Limits N-anchoring eligibility |
| A2 allowed |
Claim 1 |
Val or Ala |
Limits residue swaps at A2 |
| A8 allowed |
Claim 1 |
Asn or Ser |
Impacts pocket around Thr-A8-Ser |
| A15 allowed |
Claim 1 |
Ala or Gly |
Controls segment after Leu |
| A18 allowed |
Claim 1 |
Ser or Thr |
Impacts local conformation and potency drivers |
| A24 allowed |
Claim 1 |
Gln or His |
Controls segment near Asp/Ile |
| A27 allowed |
Claim 1 |
Met, Ile or Nle |
Restricts hydrophobic substitutions |
| A28 allowed |
Claim 1 |
Ser or Asp |
Adds polarity constraints |
| A30 length and sequence |
Claim 1 |
Any amino acid sequence of 1 to 15 residues |
Large latitude; still must attach to the specified terminus context |
| R0 |
Claim 1 |
NH2 |
Must use free amide/primary amine as stated |
| Hydrophobic tail attachment |
Claim 1 |
A1 is N-anchored by tail formula I |
Non-N-anchored modifications likely avoid |
| Tail geometry and heteroatoms |
Claim 1 |
Formula I defines cis/trans and O/S atom placements |
Alternative linker types may not meet formula I |
| Tail carbon count |
Claim 1 |
Linear main chain 5 to 7 carbons |
Strong filter against many lipophilic groups |
| Tail parameter constraints |
Claim 1 and 2,6,7 |
d+f = 1 or 2 and sum constraints; Claim 2 fixes c=0 etc. |
Must match integer constraints |
Key Takeaways
- US 5,861,379 is a chemical genus patent centered on chimeric fatty-body GRF analogs with N-anchored hydrophobic tails attached at A1 and a constrained internal GRF backbone with defined residue substitution sets.
- Claim 1 is broad on A30 (1 to 15 residues) but constrained by:
- specific allowed residues at multiple internal positions
- R0 = NH2
- strict hydrophobic tail structure rules in formula I, including a 5 to 7 carbon linear main chain and parameter sum constraints.
- Claim 8 is a specific “trans” embodiment with a fully enumerated sequence, creating a clear infringement anchor.
- The method/formulation claims (9-17) are wide across GH elevation, GH deficiency diagnostics, and multiple therapeutic/metabolic indications (growth retardation, wound/bone healing, osteoporosis, protein anabolism, obesity lipolysis, and somatroph function).
- A full competitive US patent landscape mapping other patents’ claim coverage relative to 5,861,379 cannot be completed from the claim text alone.
FAQs
1) Does the patent cover only one GRF analog or a family?
It covers a genus in Claim 1 (variable peptide residues and a formula I hydrophobic tail) plus specific embodiments like Claim 8.
2) What is the main chemical element that drives scope in Claim 1?
The hydrophobic tail attached by N-anchoring to A1 under formula I, including the 5 to 7 carbon linear main chain constraint.
3) Is the C-terminal tail (A30) tightly constrained?
No. Claim 1 allows any amino acid sequence of 1 to 15 residues for A30, subject to the overall sequence context.
4) Are formulation and methods limited to growth hormone release only?
No. Claims 12 to 17 add multiple indications: pituitary dwarfism/growth retardation, wound/bone healing, osteoporosis, protein anabolism, obesity lipolysis, and somatroph function upgrading.
5) Which claim is the clearest single-molecule target?
Claim 8, because it provides a fully specified “trans” structure and a complete peptide sequence with NH2 terminus.
References
[1] US Patent No. 5,861,379, “Chimeric fatty body GRF analogs with increased biological potency,” claims 1-17 (as provided in the prompt).
