US Patent 11,896,719: What the Claims Cover and Where the Landscape Tightens

US Drug Patent 11,896,719 is directed to methods of treating IgA nephropathy using an oral budesonide formulation that is engineered for gastroresistance and ileum targeting via (i) an enteric capsule and (ii) extended-release core coating made from a specific ethylcellulose / hydroxypropylmethyl cellulose (HPMC) polymer blend with defined loading and dissolution thresholds under USP <711> Apparatus 2 (paddle, 100 rpm). The claim set then narrows further to percent release to the ileum region, and to specific simulation media conditions, including Level 1 Fasted State Simulated Intestinal Fluid (FaSSIF) at pH 6.5 and phosphate buffer at pH 6.8, with a stated surfactant level.

What matters commercially is that the enforceable scope is not “budesonide for IgA nephropathy.” It is budesonide for IgA nephropathy delivered with a very specific release engineering profile: tight caps on acid exposure release (pH 1.2), strict early-release limits at intestinal pH, and a defined extended-release polymer blend composition and fraction of the coated core.

Claim Architecture: How the Patent Narrows from Product Mechanism to Engineering Specs

Core dependent structure

The independent claims (as provided) are two parallel independent formulations that differ primarily in the permitted ethylcellulose/HPMC blend window and tied subranges.

Claim 1:
- Core: budesonide
- Core coating: extended-release polymer blend = ethylcellulose ~51.8 wt.% and HPMC ~27.3 wt.% (of the polymer blend)
- Polymer blend fraction: 5 wt.% to 18 wt.% of total coated core weight
- Dosage form: capsule with enteric coating at 34 mg to 46 mg per capsule
- Release test: USP <711> Apparatus 2, paddle 100 rpm
- pH 1.2 (aqueous): ≤10% released by 120 min
- pH 6.5 FaSSIF Level 1 or pH 6.8 phosphate buffer:
  - ≤10% released by 30 min
  - ≥70% released by 120 min
- Dosing: daily dose ~16 mg budesonide
Claim 7: same concept and same dissolution/dose structure, but with expanded polymer windows:
- Ethylcellulose 47 wt.% to 56 wt.%
- HPMC 32 wt.% to 22 wt.%
- Polymer blend fraction: 5 wt.% to 18 wt.% of total coated core weight
- Same enteric coating mass window and same in vitro release criteria
- Daily dose ~16 mg

Second layer: ileum-region outcome (dependent claims)

Claims 2-4 / 10-12: require “substantially released” to the ileum region plus quantitative thresholds:
- ≥60% of initial content released to ileum (claim 3 and claim 11)
- ≥90% of initial content released to ileum (claim 4 and claim 12)

Third layer: exact medium selection

Claims 5 and 13: FaSSIF Level 1 at pH ~6.5
Claims 6 and 14: phosphate buffer at pH ~6.8

Fourth layer: surfactant-enabled simulation

Claims 15-16: FaSSIF Level 1 includes added surfactant ~0.5 mg/mL
Claims 17-18: phosphate buffer includes added surfactant ~0.5 mg/mL
Claims 19-20 / 21-22: additional repeats of these same media-plus-surfactant conditions tied to earlier dependencies

Fifth layer: capsule size

Claims 23-24: capsule is size 1

Sixth layer: polymer fraction and fixed-point blend ratios

Claim 8: polymer blend fraction 6 wt.% to 13 wt.% of coated core weight
Claim 9: fixed-point polymer blend fraction 9.1 wt.% (±2%) of total coated core weight
Claim 25: repeats the 6 wt.% to 13 wt.% range as a dependent claim on claim 1
Claim 26: “locking” set of fixed values:
- Ethylcellulose 51.8 wt.% (±2%)
- HPMC 27.3 wt.% (±2%)
- Polymer blend fraction 9.1 wt.% (±2%)
- Capsule size 1

Engineering Scope: What the Claims Actually Require (and How Competitors Can Miss It)

1) Acid resistance (pH 1.2) is capped

The formulation must show:

≤10% budesonide release within 120 minutes at pH ~1.2 in the USP <711> Apparatus 2 paddle test (100 rpm)

This blocks competitors from arguing general enteric protection; the claim demands a specific release outcome in a standardized test.

2) Early intestinal release is capped at 30 minutes

At intestinal pH simulation:

≤10% released within 30 minutes in either:
- FaSSIF Level 1 pH ~6.5, or
- phosphate buffer pH ~6.8

This is a second gate. Even if acid release is low, a formulation that releases too quickly post-entry falls outside.

3) Substantial extended release is required by 120 minutes

Still at intestinal pH simulation:

≥70% released within 120 minutes

The design has to balance “not too fast early” and “complete enough by 2 hours,” which narrows formulation approaches that either:

dump quickly (violates the ≤10% @30 min), or
release too slowly (violates the ≥70% @120 min).

4) Polymer blend composition is a defining structural parameter

Two different “independent claim tracks” appear:

Track A (Claim 1): fixed blend components at ~51.8 wt.% ethylcellulose and ~27.3 wt.% HPMC (as wt.% of the extended-release polymeric blend), with polymer blend fraction 5 to 18 wt.% of coated core weight.
Track B (Claim 7): broader ethylcellulose/HPMC windows (47–56 wt.% ethylcellulose; 32–22 wt.% HPMC) with same polymer blend fraction window.

5) Polymer blend loading is not an open ended “coating exists”

The claims require the extended-release polymeric blend is 5 wt.% to 18 wt.% of total coated core weight, with additional dependent limitations:

6–13 wt.% (claims 8 and 25)
9.1 wt.% ±2% (claim 9)
or the fully locked set with (claim 26) fixed blend component ratios plus the locked polymer blend fraction plus size 1 capsule.

6) Ileum-region outcome is a key narrowing outcome

Claims 2-4 and 10-12 require substantial release in the ileum region, with quantitative thresholds:

≥60% (claims 3 and 11)
≥90% (claims 4 and 12)

This is an enforcement pressure point. Competitors may meet dissolution in vitro but miss site-selective release in vivo.

Scope Map: Claim-to-Design “Hit or Miss” Matrix for Developers

Direct claim elements and likely design levers

Claim element	Literal requirement (as provided)	Likely formulation/design lever	Where competitors can miss
Enteric + core coating	Oral capsule with enteric coating 34–46 mg/capsule; core coated with extended-release polymer blend	Enteric mass and polymer coating on budesonide cores	Using enteric coating but with different mass or relying on unquantified coating performance
Acid release gate	≤10% released at pH 1.2 within 120 min	Film permeability and enteric integrity	Coatings that leak early or different polymer matrices affecting diffusion in acidic media
Intestinal early release gate	≤10% released in ≤30 min at pH 6.5 or 6.8	Polymer erosion/diffusion kinetics	Faster erosion polymers, insufficient coating mass, or different blend ratio
Extended release completion	≥70% released by 120 min at intestinal pH	Release kinetics tuned for 2-hour window	Too-slow systems that don’t reach 70% by 120 min
Polymer blend composition	Ethylcellulose and HPMC wt.% values in the blend (fixed in claim 1/26; ranged in claim 7)	Blend formulation	Different ratios that still look “close” but fall outside numeric windows
Polymer blend fraction	5–18 wt.% (or narrower dependent ranges) of coated core weight	Coating weight fraction	Slightly higher or lower coating fraction
Ileum targeting	“Substantially released to ileum” with ≥60% or ≥90% thresholds	Site targeting and enteric behavior	Achieving dissolution but not ileum localization in vivo
Simulation medium specificity	FaSSIF Level 1 pH 6.5 or phosphate buffer pH 6.8	Choice of test medium	Different media compositions or omission of surfactant condition when invoked
Surfactant condition	Added surfactant ~0.5 mg/mL in specified media	In vitro test setup	Different surfactant level or different “Level” designation
Capsule size	Size 1 capsule	Manufacturing form factor	Different capsule size if asserted in dependent claims

Patent Landscape: Practical Positioning Versus Likely Design-Around Space

What this patent blocks

As written, 11,896,719 blocks therapeutic claims that combine: 1) IgA nephropathy treatment with budesonide, and 2) an oral capsule delivery system that satisfies the exact USP <711> App. 2 dissolution performance gates, and 3) a coated core using the specified ethylcellulose/HPMC extended-release blend with constrained weight fraction, and 4) (in later dependents) ileum-region release percentages.

That creates a relatively narrow “claim corridor.” A competitor must either:

replicate the dissolution profile tightly, and
hit the polymer blend numbers, or
avoid the claim by changing at least one “numeric gate” so that the dissolution criteria and/or polymer composition falls outside.

How dependent claims expand enforcement

Dependent claims create multiple ways to land on infringement depending on formulation characteristics:

Even if a product misses claim 1 fixed ratios, it can still land under claim 7 broad polymer ranges.
If a product’s dissolution kinetics align but ileum targeting differs, it may still face exposure under the non-ileum claims (1 or 7) but potentially escape those dependents (2-4, 10-12).
If a product uses specific simulation media with surfactant, it can be brought under 15-22 if the media matches the surfactant specification.
If capsule form factor differs (not size 1), it avoids 23-24 and the tight locked configuration 26 while still potentially meeting the broader dissolution/polymers unless those dependents are asserted.

Design-around levers that most directly affect literal claim elements

Based on the claim text alone, the most “literal” escape levers are:

Shift dissolution timing outside the windows:
- make acid release exceed 10% by 120 min, or
- make intestinal early release exceed 10% by 30 min, or
- make intestinal release fall below 70% by 120 min.
Change the polymer blend composition or its fraction:
- move ethylcellulose/HPMC ratios outside the windows (claim 1 fixed; claim 7 ranged; claim 26 fixed ±2%).
- move polymer blend loading outside 5–18 wt.% (or narrower 6–13, 9.1 ±2%).
Change capsule parameters:
- avoid enteric coating mass 34–46 mg per capsule
- use a capsule size other than size 1 if the narrower dependents are asserted.
Change site-release behavior:
- if in vivo ileum release cannot reach ≥60% or ≥90%, those dependents are harder to prove.

Claims as an Enforcement Tool: Why this is “Spec-Heavy” rather than “Genus-Heavy”

The claims do not read as “any modified-release budesonide capsule.” They read as:

a specific polymer chemistry pairing (ethylcellulose + HPMC) with explicit blend proportions,
a specific amount of that polymer blend within the coated core,
a standardized in vitro release performance profile with numeric cutoffs,
a standard enteric coating mass per capsule, and
a standard daily dose (about 16 mg).

For infringement analysis, the practical consequence is that any challenger needs to evaluate the product against the full combined set of numeric requirements. Partial overlap is unlikely to neutralize the claim unless the product cleanly misses one of the hard gates.

Key Takeaways

US 11,896,719 is a method-of-use patent for IgA nephropathy using orally administered budesonide with a spec-defined enteric capsule and extended-release coated core.
The patent scope is defined by numeric dissolution thresholds under USP <711> App. 2 at 100 rpm, including:
- ≤10% release at pH 1.2 by 120 min
- ≤10% release at pH 6.5 FaSSIF Level 1 or pH 6.8 phosphate buffer by 30 min
- ≥70% release at the same intestinal media by 120 min
The formulation must include an ethylcellulose/HPMC extended-release polymer blend with constrained:
- component ratios (fixed in claim 1 and locked in claim 26; ranged in claim 7),
- blend loading as % of coated core weight (5–18 wt.% base; narrowed to 6–13 or 9.1 ±2% in dependents).
Dependent claims add ileum-region release thresholds (≥60% or ≥90%) and specific dissolution media variants (FaSSIF Level 1 pH 6.5, phosphate pH 6.8, with 0.5 mg/mL surfactant when invoked), plus size 1 capsule constraints.

FAQs

1) Is 11,896,719 broad across all budesonide IgA therapies?

No. It requires budesonide delivery that meets the specific polymer blend plus the USP <711> dissolution release profile under Apparatus 2 (paddle, 100 rpm) with tight numeric caps at pH 1.2 and intestinal pH.

2) What is the hardest “literal” element to design around?

The combined set of numeric dissolution gates plus the polymer blend composition and loading. Missing any one hard gate can move the product outside the claim.

3) Do the claims require in vivo proof of ileum release?

The dependent claims require the method as reciting ileum-region release thresholds (≥60% or ≥90%), which effectively ties infringement to ileum localization behavior in addition to dissolution test performance.

4) Does the patent allow both FaSSIF and phosphate buffer as the intestinal medium?

Yes. The claims state the pharmaceutically-relevant dissolution medium can be FaSSIF Level 1 at pH ~6.5 or phosphate buffer at pH ~6.8, and they further add surfactant specifics when those dependents are invoked.

5) How do capsule specifications affect infringement risk?

The claims include dependent limitations for size 1 and a required enteric coating mass per capsule (34–46 mg). Products that use different capsule size or enteric mass can avoid those dependents while still potentially facing the broader claim elements.

References

[1] USP <711> Dissolution (apparatus and testing framework), United States Pharmacopeia (as referenced in the claim language).

Applicant	Tradename	Generic Name	Dosage	NDA	Approval Date	TE	Type	RLD	RS	Patent No.	Patent Expiration	Product	Substance	Delist Req.	Patented / Exclusive Use	Submissiondate
Calliditas	TARPEYO	budesonide	CAPSULE, DELAYED RELEASE;ORAL	215935-001	Dec 15, 2021		RX	Yes	Yes	⤷ Start Trial	⤷ Start Trial				REDUCTION IN LOSS OF KIDNEY FUNCTION AND REDUCTION OF PROTEINURIA IN ADULTS WITH PRIMARY IMMUNOGLOBULIN A NEPHROPATHY (IGAN) WHO ARE AT RISK OF DISEASE PROGRESSION, BY RELEASE OF BUDESONIDE FROM THE FORMULATION	⤷ 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	2023210461	⤷ Start Trial
Canada	3249575	⤷ Start Trial
Chile	2024002201	⤷ Start Trial
>Country	>Patent Number	>Estimated Expiration	>Supplementary Protection Certificate	>SPC Country	>SPC Expiration

Details for Patent: 11,896,719

Which drugs does patent 11,896,719 protect, and when does it expire?

Summary for Patent: 11,896,719