United States Patent 10,058,600 Claims and US Patent Landscape for E. coli AcfD (orf3526) Immunogenic Fragments and Vaccines

United States Patent 10,058,600 claims immunogenic polypeptides and vaccines built from fragments or mutants of the E. coli AcfD (orf3526) protein with two core constraints: (i) deletion of a C-terminal portion (at least the last 300 or at least the last 400 amino acids), and (ii) retained functional immunogenicity relative to full-length AcfD while decreasing protease activity. The claim set also expands protection to purified fragments and vaccine compositions and multi-component vaccines with a broad menu of additional bacterial antigens.

What is US Patent 10,058,600 protecting: immunogenic polypeptides and vaccines from E. coli AcfD (orf3526) fragments?

Core protection granted by claim scope
US 10,058,600 is directed to:

Immunogenic polypeptides comprising fragments or mutants of E. coli AcfD (orf3526).
Fragments that exclude at least the last 300 C-terminal amino acids (claim 1) or exclude at least the last 400 C-terminal amino acids (claim 2).
Amino acid sequences defined by SEQ ID NOs: 1–19 for the parent AcfD protein in the claim.
A functional performance requirement: the fragment “raises at least 70% of the immune response” as compared to the full-length AcfD.
A functional mechanistic requirement: “decreased protease activity” versus full-length AcfD.
Downstream product claims: purified polypeptides (claim 3), and vaccine compositions and vaccines (claims 4–8) formulated with an adjuvant and optionally co-administered with a long list of other bacterial antigens.

Claim construction signals (from the text provided)

The deletion is absolute and structural: the polypeptide “does not comprise at least the last X C-terminal amino acids,” meaning the protected fragments must be truncated from the C-terminus at or beyond that threshold.
The inventiveness is anchored to a functional balancing act:
- immunogenicity retention (≥70% relative immune response)
- protease activity reduction (a measurable functional property)
The “SEQ ID NOs: 1–19” language indicates that the patent is claiming a finite set of specific sequence variants for AcfD (orf3526) as the starting point for fragment/mutant embodiments. This can narrow literal coverage to variants represented by those sequences, even though the functional claim language broadens coverage to fragments derived from those sequences.

Which parts of AcfD (orf3526) are excluded and what does that imply for coverage?

Truncation thresholds

Claim 1: fragments/mutants exclude ≥300 amino acids from the C-terminus.
Claim 2: fragments/mutants exclude ≥400 amino acids from the C-terminus.

In practice, these two cutoffs define at least two protected “zones” of truncation. Any design that truncates less than 300 C-terminal amino acids would fall outside the literal scope of these independent claims as provided.

Implication for designing-around

A competitor aiming to avoid literal infringement would target fragments that either:
- retain ≥1 amino acid within the excluded region beyond the stated threshold, or
- do not meet the defined “decreased protease activity” and ≥70% immune response functional requirements.
If “decreased protease activity” and “raises at least 70%” are implemented through assay-specific definitions, the factual record matters for infringement (but the claim language already makes those functional outcomes central to the claim).

How do claims define immunogenicity and protease activity without specific assays?

The provided claims do not specify:

which immune readout (binding titers, neutralization, T-cell markers, etc.)
which assay standard
what timing/dose regimen is used to compare “at least 70% of immune response”

Even so, the claim text makes these properties litigation-grade anchors: a direct comparison to full-length E. coli AcfD (orf3526) in a “subject” and the functional performance thresholds are necessary claim elements.

What is covered by the “mutant” language in addition to fragments?

Claims 1 and 2 include “fragment or mutant” polypeptides. That means:

A truncated fragment is not the only infringement path; a mutant may also be within scope if it also satisfies the “does not comprise at least the last X C-terminal amino acids” limitation and the functional immunogenicity/protease constraints.
For a competitor, “mutant” does not eliminate the C-terminal deletion constraint; any mutant still must be missing the specified terminal portion.

Which sequences and variants are actually claimed: what do SEQ ID NOs: 1–19 imply?

Finite sequence set with a functional overlay
“wherein the E. coli AcfD (orf3526) protein has an amino acid sequence selected from the group consisting of SEQ ID NOs: 1–19” constrains the universe of covered starting proteins.

That typically creates two practical implications:

Literal infringement is easiest where the challenged product’s parent AcfD variant matches one of the listed SEQ ID NOs (or a fragment/mutant clearly derived from that exact sequence).
Design-around by sequence may be feasible if the competitor uses a substantially different AcfD sequence not captured by SEQ ID NOs 1–19, even if it produces similar immune performance and protease reductions. However, “mutant” and fragment derivation can complicate the boundary depending on how those SEQ ID-defined embodiments are described in the specification.

Limits of the information provided You supplied only the claim text, not the specification’s definitions of each SEQ ID sequence, nor the complete claim-to-sequence mapping. Without those, coverage cannot be enumerated beyond the claim’s express SEQ ID constraint.

What formulations are protected by US 10,058,600: adjuvanted vaccines and multi-antigen compositions?

Single-antigen vs multi-antigen vaccine coverage

The claim tree expands as follows:

Claim 4: immunogenic composition = claim 1 polypeptide + adjuvant.
Claim 5: vaccine = claim 3 purified polypeptide + adjuvant.
Claim 6: vaccine = claim 1 polypeptide + adjuvant.
Claim 7 and Claim 8: vaccines of claims 5 and 6 add an additional vaccine component chosen from a long list of antigens from many bacterial species.

Adjuvant coverage The claims require an “adjuvant” but do not limit by:

adjuvant type (alum, MF59-like, AS01-like, TLR agonists, etc.)
adjuvant dose ratio
route of administration

So, within literal scope, any adjuvant that is used in the disclosed vaccine formulation could satisfy the “adjuvant” element.

What is the practical meaning of the broad antigen list in claims 7 and 8?

Claims 7 and 8 allow co-formulation with many antigens. Functionally, this helps prevent a competitor from arguing “we used a different combination of antigens” as a way to avoid infringement, as long as the challenged vaccine still includes the claimed AcfD immunogenic polypeptide fragment and adjuvant.

The list includes, among others:

Neisseria meningitidis
Streptococcus pneumoniae
Bordetella pertussis
Staphylococcus aureus / epidermis
Clostridium tetani / diphtheriae
Haemophilus influenzae type B (Hib)
Pseudomonas aeruginosa
Legionella pneumophila
Enterococcus (faecalis/faecium)
Helicobacter pylori
Bacillus anthracis / Yersinia pestis
Mycobacterium tuberculosis
Listeria monocytogenes
Vibrio cholerae / Salmonella typhi
Borrelia burgdorferi
Porphyromonas gingivalis
Klebsiella

For freedom-to-operate, this matters most when assessing multi-valent bacterial vaccines or omnibus formulations.

How strong are the claims likely to be: what are the key elements for invalidity and non-infringement risk?

Strength drivers in claim language

The claim’s strongest enforceability anchors are:

Structural limitation: C-terminal truncation thresholds (300/400 amino acids).
Sequence constraint: AcfD parent sequence in SEQ ID NOs: 1–19.
Functional performance:
- ≥70% immune response relative to full-length AcfD
- decreased protease activity

These three elements together raise the bar for generic “immunogenic fragment” arguments, because a potential infringer must show not only sequence/structure differences but also the same performance outcomes.

Invalidity exposure points

Even without the full specification and prosecution history, claim text suggests typical invalidity pressure points:

Written description / enablement risk if the specification does not clearly support:
- a broad range of fragments spanning the 300/400 truncation thresholds
- mutants outside a narrow set of concrete examples
- the functional property claims (≥70% immune response; decreased protease activity) across the full scope
Indefiniteness risk is lower if the specification defines:
- what “immune response” means
- what assay compares “as the E. coli AcfD protein”
- what constitutes “protease activity” and how it is measured But these are not in the claims you provided; they live in the spec.

Non-infringement pathways

A challenger typically attacks one of:

the C-terminal deletion threshold (less than 300 or 400 amino acids removed)
mismatch to one of the SEQ ID NOs variants
failure to meet ≥70% immune response benchmark
failure to show decreased protease activity relative to full-length AcfD

For product defense, the key is having robust characterization data tied to the claim’s functional elements.

When does US 10,058,600 lose exclusivity: what expiration framework applies?

You provided claim text only. A precise exclusivity timeline (scheduled patent expiration, potential PTA, terminal disclaimer impact, and enforceability dates) requires at least:

filing date and priority chain
grant date
any terminal disclaimer, reissue, or continuation history

Without those facts, an accurate exclusivity timeline cannot be produced.

What is the Orange Book status of US 10,058,600?

US 10,058,600 is directed to vaccines (immunogenic polypeptides) and would typically be associated with biologics or vaccines, not small-molecule drugs. Orange Book applicability depends on whether a relevant product is an FDA-approved drug with an NDA and Orange Book listing.

No product association or listing details were provided, so a definitive Orange Book status cannot be stated from the information available.

How does US 10,058,600 compare with adjacent AcfD fragment and protease-reduced immunogen patents?

Claim differentiation is likely to be functional Most immunogenic protein fragment patents in this space distinguish on:

specific truncation region(s)
immune readouts
antigen presentation and adjuvant system
reduction in undesirable activity (here, decreased protease activity)

US 10,058,600’s distinctive feature is the explicit pairing of:

C-terminal deletion (300/400 amino acids) and
functional immunogenicity retention (≥70%) and
functional activity reduction (protease)

That combination is a common pattern in vaccine antigen engineering claims, where a full-length protein has problematic activity, and a fragment is engineered to retain immunogenic epitopes while removing functional or safety liabilities.

But without other patent numbers from the same family or competitors, landscape ranking is not possible under your constraint.

What patent litigation could affect freedom-to-operate for these AcfD immunogens and vaccines?

Litigation risk assessment requires:

case captions
parties
asserted claims
jurisdictions
outcomes or settlements
whether the patent is stayed, enforced, or narrowed

No litigation information was provided, so a reliable litigation landscape cannot be generated.

What generic or biosimilar entry risks exist for vaccines covered by US 10,058,600?

Vaccines generally do not follow “generic” pathways for NDA drugs, and “biosimilar” does not map cleanly onto synthetic polypeptide fragments unless a biologic license application and “BLA” framework applies to the product in question.

A valid entry-risk analysis requires the product’s regulatory pathway (NDA vs BLA), the exact claim-to-product mapping, and whether there are other controlling patents around:

antigen sequence
truncation window
adjuvant and formulation
manufacturing and purification

Those facts are not included in the input.

Key claim-by-claim breakdown of US 10,058,600 as provided

Claim	What it covers	Main limiting elements
1	Immunogenic polypeptide (fragment or mutant)	AcfD (orf3526) SEQ ID NOs 1–19; does not include at least last 300 C-terminal amino acids; raises ≥70% immune response vs full-length AcfD; decreased protease activity vs full-length
2	Immunogenic polypeptide (fragment)	Same as claim 1 but truncation excludes at least last 400 C-terminal amino acids
3	Purified immunogenic polypeptide of claim 1	Purification limitation on claim 1 product
4	Immunogenic composition	Claim 1 polypeptide + adjuvant
5	Vaccine	Claim 3 purified polypeptide + adjuvant
6	Vaccine	Claim 1 polypeptide + adjuvant
7	Vaccine with added antigens	Claim 5 vaccine + additional antigens selected from long list
8	Vaccine with added antigens	Claim 6 vaccine + additional antigens selected from long list

Key Takeaways

US 10,058,600 targets engineered E. coli AcfD (orf3526) immunogens built from C-terminally truncated fragments/mutants with explicit truncation thresholds of 300 or 400 amino acids.
The claims require a functional performance package: ≥70% immune response relative to full-length AcfD and decreased protease activity versus full-length AcfD.
Protection extends to purified polypeptides and adjuvanted vaccines, including multi-antigen vaccine formulations with a broad selectable antigen list.
Enforceability and infringement typically hinge on whether a candidate immunogen matches the SEQ ID NOs: 1–19 universe and meets the functional assay-defined constraints.

FAQs

How do the “at least the last 300” and “at least the last 400” C-terminal amino acid limits affect infringement for AcfD truncation products?
What does “raises at least 70% of the immune response” likely require for assay design and proof of infringement?
Do claims covering “fragment or mutant” still require the C-terminal deletion threshold to be met?
How do the claims treat vaccine multi-antigen formulations if a competitor uses different additional bacterial antigens?
What evidence typically matters for proving “decreased protease activity” compared with full-length E. coli AcfD?

References (APA)

US Patent 10,058,600 (claims provided in user input).

Applicant	Tradename	Biologic Ingredient	Dosage Form	BLA	Approval Date	Patent No.	Expiredate
Emergent Biodefense Operations Lansing Llc	BIOTHRAX	anthrax vaccine adsorbed	Injection	103821	November 12, 1998	⤷ Start Trial	2034-10-27
>Applicant	>Tradename	>Biologic Ingredient	>Dosage Form	>BLA	>Approval Date	>Patent No.	>Expiredate

Patent: 10,058,600

Summary for Patent: 10,058,600