Scope and patent landscape for US Drug Patent 12,370,174 (atrasentan for IgA nephropathy proteinuria)

US Patent 12,370,174 is a US method-of-treatment patent focused on reducing proteinuria in primary IgA nephropathy (IgAN) with atrasentan given in a defined dose band (0.20 to 1.5 mg once daily), using a defined patient characterization (exclusion of certain comorbid diagnoses; baseline proteinuria and renal function thresholds; background stable RAS inhibition), and measured proteinuria response targets at defined timepoints. The claim set is structured to support multiple enforcement theories: (1) broad dose-range method claims, (2) narrower embodiments for salt form (hydrochloride), oral once-daily tablet dosing, (3) tighter eligibility filters (not previously diagnosed with diabetic nephropathy, HIV/AIDS, acute kidney failure), (4) baseline enrichment (proteinuria ≥1.0 and ≥1.5 g/day; eGFR ≥30 mL/min/1.73m²; combined thresholds), (5) response end points (drop below 1.0/0.5/0.3 g/day; ≥30% reduction; ≥30% reduction at 12 and 36 weeks), and (6) combination-context method claims with maximally tolerated stable RAS inhibitors (ACEi or ARB). This design increases the probability of capturing real-world prescribing patterns that match clinical trial inclusion and titration logic.

What is US Patent 12,370,174 and what does it claim about atrasentan in IgA nephropathy?

Answer: US 12,370,174 claims methods of reducing proteinuria in human subjects with primary IgA nephropathy using atrasentan in a specific dosing range and regimen, with additional claim layers tied to salt form, route/frequency, patient eligibility exclusions, baseline severity, background RAS inhibitor status, and quantitative proteinuria response outcomes.

Core claim architecture

The independent anchor is claim 1 (and a parallel dosing/embodiment set at claim 2). Dependent claims then narrow along:

Dose: about 0.20 to 1.5 mg atrasentan (or equivalent salt), plus a focal dose at about 0.75 mg.
Salt form: atrasentan hydrochloride.
Dosage form/administration: oral tablet once daily.
Patient eligibility exclusions: no prior diagnosis of diabetic nephropathy, HIV/AIDS, or acute kidney failure.
Baseline severity thresholds:
- proteinuria ≥1 g/day (and ≥1.5 g/day, plus ≥2 g/day)
- eGFR ≥30 mL/min/1.73m²
- combined proteinuria + eGFR thresholds
Response thresholds:
- proteinuria reduced to below 1.0 g/day, and further to below 0.5 or below 0.3 g/day
- ≥30% reduction
- ≥30% reduction after 12 weeks and/or after 36 weeks
Background therapy:
- previously received or concomitantly receiving maximally tolerated stable RAS inhibitor
- RAS inhibitor specifically ACE inhibitor or ARB

What the claim set indicates about clinical grounding

The inclusion/exclusion and endpoints align tightly with how IgAN proteinuria trials are typically designed: baseline proteinuria thresholds in g/day, renal function cutoffs, stable background RAS inhibition, and time-bounded proteinuria reductions (12 and 36 weeks). The patent is therefore likely to map to a clinical development program and may be intended to cover both trial and “real-world trial-like” prescribing.

What is the scope of Claim 1 (dose band, disease, and method outcome) in US 12,370,174?

Answer: Claim 1 broadly covers administering 0.20 to 1.5 mg atrasentan (or equivalent salt) to a patient with primary IgA nephropathy to reduce proteinuria, without requiring the additional narrow eligibility filters that appear only in dependent claims.

Claim 1 element-by-element

Action: administering atrasentan (or salt)
Human condition: primary IgA nephropathy (IgAN)
Dose range: about 0.20 mg to about 1.5 mg
Purpose/outcome: “thereby reducing proteinuria”

Practical infringement “coverage” implied by claim 1

Dose band capture: any prescriber or label that lands within 0.20–1.5 mg likely falls within the numeric dose limitation, subject to “about” interpretation.
Salt neutrality: claim 1 includes “atrasentan, or an equivalent amount of a pharmaceutically acceptable salt thereof,” so salt selection does not avoid the base claim.
Outcome language: the claim is framed as a method “thereby reducing proteinuria.” In litigation, that tends to function as a therapeutic effect limitation. A defendant can try to contest whether a given regimen achieves the asserted proteinuria reduction, but that is often fact-intensive.

How does claim 2 narrow the method in US 12,370,174 (0.75 mg and salt form)?

Answer: Claim 2 tracks claim 1 but explicitly recites about 0.75 mg and supports salt-form specificity via its dependent structure.

Key narrowing features in the claim set provided

A specific dose point: about 0.75 mg
Salt-form embodiment is reinforced through claims that specify atrasentan hydrochloride (claims 3 and 4)

Why this matters

If a generic or competitor selects a dose outside the “about 0.20–1.5 mg” band, claim 1 may be missed, but claim 2 still targets about 0.75 mg. Conversely, if any formulation uses 0.75 mg exactly (or within “about”), claim 2 and its dependent salt/tablet/oral embodiments become prominent enforcement targets.

What formulations and dosing regimens are protected (hydrochloride salt and oral once-daily tablet)?

Answer: The patent includes embodiments specifying atrasentan hydrochloride and oral once-daily tablets, which can matter for label design, product switching, and attempt-to-design-around with different salt forms or dosing schedules.

Salt scope

Claims 3–4: atrasentan is administered as atrasentan hydrochloride.

Dosage form and frequency scope

Claims 5–6: atrasentan (or salt) administered as a tablet orally once daily.

Claim strategy implications

If a generic company seeks to switch from hydrochloride to another acceptable salt, it may still be captured by claim 1 (salt-agnostic) while avoiding the dependent claim 3/4 embodiment. That said, dependent claims can still be separately infringed if a specific product uses hydrochloride and dosing matches.

What patient eligibility exclusions are included in US 12,370,174 (diabetic nephropathy, HIV/AIDS, acute kidney failure)?

Answer: The patent includes method claims limiting the treated subject to those not previously diagnosed with diabetic nephropathy, HIV/AIDS, or acute kidney failure.

How the exclusion operates in the claim set

Claims 7–8: subjects have not been previously diagnosed with one or more of:
- diabetic nephropathy
- HIV/AIDS
- acute kidney failure

Scope consequences

This is a classic “inclusion/exclusion” compliance lever. If a treatment regimen is used in a broader comorbidity population, a defendant might argue that not all treated subjects meet the exclusion criteria, weakening “method for a human subject having…” style arguments tied to the excluded diagnoses.

What baseline proteinuria and renal function thresholds are protected?

Answer: The patent targets enriched baseline disease severity using multiple proteinuria and eGFR thresholds, including combined filters that narrow to a specific clinical phenotype.

Baseline proteinuria thresholds

Claims 9–13:
- proteinuria ≥1 g/day (claims 9–11)
- proteinuria ≥1.5 g/day (claims 12–13)
Claim 29:
- proteinuria ≥2 g/day

Renal function threshold

Claims 14–15:
- eGFR ≥30 mL/min/1.73m²

Combined baseline requirement

Claims 16–17:
- proteinuria ≥1 g/day and/or eGFR ≥30
- The “and/or” wording broadens the interpretation relative to a strict “both” requirement, but it still creates an eligibility filter beyond claim 1.

Why these dependent thresholds matter

They give the patent multiple claim layers tied to trial-like cutoffs. If a competitor product is used outside these thresholds (e.g., lower proteinuria, lower eGFR, or different comorbidity mixes), the dependent claims may be avoided while claim 1 remains at issue unless the competitor also steers dosing and use outside the claim’s broad scope.

What proteinuria response endpoints are claimed (below 1.0 g/day, ≥30%, 12 weeks, 36 weeks)?

Answer: The patent claims both absolute reductions (cutoffs at 1.0, 0.5, 0.3 g/day) and relative reductions (≥30%), including time-specific embodiments at 12 and 36 weeks.

Absolute proteinuria reductions

Claim 18: reduced to below 1.0 g/day
Claim 19: reduced to below 1.0 g/day, or below 0.5 g/day, or below 0.3 g/day

Relative proteinuria reductions

Claims 20–22:
- proteinuria reduced by at least about 30%
Claim 23–24:
- ≥30% after 12 weeks and/or ≥30% after 36 weeks

Scope implications

A dosing regimen can potentially infringe the patent even if it does not meet the absolute cutoff, so long as it meets the relative reduction threshold and the timing is satisfied for the relevant dependent claims.
Time dependence creates leverage in litigation discovery: measured urine protein outcomes and timing can become central.

How does the patent handle background RAS inhibition (maximally tolerated stable ACEi/ARB)?

Answer: The patent includes dependent claims where the subject is receiving or has received maximally tolerated stable RAS inhibitors, with ACE inhibitors and ARBs called out.

Claims and structure

Claims 25–26: previously received or concomitantly receiving maximally tolerated stable dose of one or more RAS inhibitors
Claims 27–28: RAS inhibitor is an:
- angiotensin-converting enzyme (ACE) inhibitor
- or an angiotensin II receptor blocker (ARB)

Infringement relevance

If a product is marketed or used without stable background RAS inhibition, dependent claims 25–28 may be harder to assert. Claim 1 remains available as a broader hook unless limited by a “patient having” element. In practice, most IgAN protocols use stable RAS blockade, so the dependent claims often track standard care.

What do the claim tiers suggest about enforceability and design-around paths?

Answer: The claim set is tiered to preserve enforceability against multiple real-world implementation variants: dose, salt, dosing frequency, patient phenotype, baseline cutoffs, and response/time endpoints.

Likely “design-around” pressure points

Dose range: stay outside 0.20 to 1.5 mg and outside about 0.75 mg
Salt form: avoid hydrochloride (but may still fall into broader salt-agnostic claim 1)
Dosing frequency/dosage form: avoid oral once-daily tablets (e.g., different formulation schedule)
Population selection: treat only patients with comorbidities that violate the exclusion language
Baseline severity: avoid treating patients below specified proteinuria and eGFR thresholds if trying to avoid dependent claims
Measured endpoints: timing and achieving thresholds is fact-dependent; it is rarely a reliable design-around.

Litigation consequence

Because claim 1 is broad and dependent claims add narrower embodiments, the patent’s strongest posture usually comes from showing that the accused use fits the broad independent claim, then using dependents to corroborate the use-case matching trial-like criteria.

How does US 12,370,174 compare to typical atrasentan/IPR landscapes for IgA nephropathy?

Answer: This patent fits the common pattern for late-stage development patents: method-of-use claims anchored on a clinically defined dosing regimen and clinically defined endpoints in a specific renal disease.

Shared industry pattern

receptor antagonist (atrasentan) + IgAN + proteinuria reduction endpoints
background stable RAS therapy for standardization
timepoints consistent with clinical program milestones

Distinguishing elements within this patent

The claim set explicitly includes:
- numerical dose band (0.20 to 1.5 mg)
- specific 0.75 mg embodiment
- hydrochloride and oral once-daily tablet embodiments
- multiple baseline severity thresholds
- both absolute and relative proteinuria response cutoffs
- 12-week and 36-week response embodiments
- comorbidity exclusions for diabetic nephropathy, HIV/AIDS, acute kidney failure

What is the patent estate coverage likely to be (claims breadth vs likely dependent vulnerability)?

Answer: Based on the claim text provided, the patent has meaningful breadth through claim 1, with substantial “stacking” of dependent claim limitations that mirror inclusion criteria and endpoints. That increases the number of fact patterns where infringement can be asserted, but each dependent claim also creates a potential way for defendants to challenge elements by showing non-matching patient selection or outcomes.

Coverage map (from your claim text)

Claim layer	Limitation type	Key elements in 12,370,174
Independent method	Dose + disease + effect	Primary IgAN; administer atrasentan 0.20–1.5 mg; reduce proteinuria
Dose-specific	Narrow dose	about 0.75 mg
Salt/form	Formulation	atrasentan hydrochloride
Administration	Regimen	oral tablet once daily
Eligibility exclusions	Patient history	no prior diabetic nephropathy, HIV/AIDS, acute kidney failure
Baseline severity	Baseline thresholds	proteinuria ≥1, ≥1.5, ≥2 g/day; eGFR ≥30
Endpoint/time	Outcome definition	below 1.0/0.5/0.3 g/day; ≥30% reduction at 12 and 36 weeks
Background therapy	Concomitant standard of care	stable maximally tolerated RAS inhibitors; ACEi/ARB

Key Takeaways

US 12,370,174 is a method-of-use patent covering atrasentan for reducing proteinuria in primary IgA nephropathy, anchored on a specific dose band (0.20 to 1.5 mg).
The claims include layered limitations for dose (0.75 mg), salt form (hydrochloride), oral once-daily tablets, and clinically standardized patient selection and endpoints.
The strongest enforcement hooks are the combination of claim 1 breadth and the dependent claims that tightly track trial-style criteria: baseline proteinuria/eGFR, stable RAS inhibition, and proteinuria reductions including ≥30% at 12/36 weeks.
Potential design-around strategies focus on escaping the dose band, avoiding hydrochloride, changing dosing regimen/form, or treating populations not matching dependent eligibility filters.

FAQs

Does US 12,370,174 require a specific proteinuria measurement method (e.g., urine protein-to-creatinine ratio vs 24-hour protein)?
Can an at-risk product avoid infringement by using a different atrasentan salt than hydrochloride?
What happens if a patient’s baseline proteinuria is between 0.5 and 1.0 g/day under the dependent claims?
Is the “≥30% reduction after 12 weeks” requirement enforceable if later timepoints still show benefit?
How does concomitant ACE inhibitor vs ARB use change the risk profile under the RAS-inhibitor dependent claims?

References

United States Patent Application/Patent No. 12,370,174 (claims as provided by user).

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	VANRAFIA	atrasentan hydrochloride	TABLET;ORAL	219208-001	Apr 2, 2025		RX	Yes	Yes	⤷ Start Trial	⤷ Start Trial				TREATMENT OF PRIMARY IMMUNOGLOBULIN A NEPHROPATHY (IGAN)	⤷ 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	2020404984	⤷ Start Trial
Brazil	112022012075	⤷ Start Trial
Canada	3161516	⤷ Start Trial
China	113272013	⤷ Start Trial
China	116173014	⤷ Start Trial
China	116327758	⤷ Start Trial
>Country	>Patent Number	>Estimated Expiration	>Supplementary Protection Certificate	>SPC Country	>SPC Expiration

Summary for Patent: 12,370,174