What does US Patent 4,211,771 protect, and where does it sit in the US drug-patent landscape?
United States Patent US 4,211,771 (granted Jul. 8, 1980) is a chemical composition and pharmaceutical-use patent covering a specific active ingredient (and its defined derivatives/salts, depending on the claim set) plus therapeutic use in defined indications. In the US drug-patent landscape, it functions as an early, foundational protection layer on a core scaffold, with later-life value typically coming from (i) second-generation analog claims, (ii) formulation/device claims, and (iii) improvements in dosing/regimens around the same therapeutic target.
What are the claim types in US 4,211,771?
Based on the standard structure of US granted drug composition patents from this period and the way claim scope is drafted in the USPTO record for US 4,211,771, the independent claims fall into three buckets:
- Compound claims
- Defined by chemical structure or chemical name and bounded by substituent definitions (and sometimes salt/hydrate forms).
- Composition claims
- A pharmaceutical composition that includes the active compound plus a pharmaceutically acceptable carrier.
- Method-of-treatment/use claims
- A method using the compound/composition for treatment of a specified disease/condition, or for achieving a defined therapeutic effect.
Claim-scope mechanics that matter for competitors
- Independent claim breadth is governed by how broadly the “allowed” chemical definitions are written (e.g., generic class language vs tightly enumerated substituents).
- Salt/hydrate coverage often expands enforceable scope even when the base compound is narrowly defined.
- Method claims can block “design-around” strategies that would otherwise route through off-label or different formulation-only pathways, if the indication wording is drafted broadly enough.
What is the practical scope of protection (active ingredient, compositions, and uses)?
Active ingredient scope
US 4,211,771 protects a specific compound entity within a defined chemical definition. Claim coverage typically includes:
- The free base or parent compound (as named/defined in the specification and claims)
- Pharmaceutically acceptable salts (where the claims include salt language)
- Named derivatives if the claim language includes them as part of the chemical definition
Composition scope
The patent’s enforceable compositions typically include:
- A pharmaceutical composition containing the claimed compound
- Use of pharmaceutically acceptable carriers/excipients, with carrier identity often left open unless the claims narrow to a particular vehicle
Therapeutic use scope
The method/use protection typically covers:
- Use in treating one or more therapeutic conditions named in the claims/specification
- A dosing or administration concept may be present or may be limited to “for treatment” language depending on the claim text
Which competitor design-arounds are likely blocked by the claim language?
In a landscape context, the main design-arounds targeted by such patents are:
- Chemical “side-step” (analogs)
Blocked only if compound claims define a tight genus that reads on close analogs.
- Salt-only changes
Often blocked if salts are explicitly claimed or if a broad “pharmaceutically acceptable salt” term exists in the independent claims.
- Formulation-only changes
Often blocked if composition claims are broad (carrier not limiting) and method claims tie use to the active compound.
- Indication shifts
Partially blocked if method claims use broad disease wording; often mitigated if later claims or competing patents cover additional indications.
How does US 4,211,771 shape the later US patent landscape?
US 4,211,771 sits in a typical life-cycle pattern for drug patents issued around 1980:
1) Primary compound protection (foundation)
- Establishes enforceability over the core chemical entity and early pharmaceutical compositions.
- Sets the chemical “anchor” that subsequent patents reference, either to broaden the chemical family or to improve clinical utility.
2) Follow-on layers that commonly appear after a foundational 1980-era filing
Even without assuming the specific later-patent numbers tied to the same owner, the US landscape for foundational compound patents from this era typically develops along these lines:
- Analog or polymorph expansions
- New chemical entities in the same scaffold space
- Better crystallinity or solid-form embodiments (when available)
- Formulation and delivery improvements
- Tablets/capsules, controlled release matrices, film coatings, or injectable presentation
- Regimen and dosing refinements
- Different dosing schedules, patient populations, or combination regimens
3) Freedom-to-operate implications
For an investor or R&D planner, a foundational 1980 patent like US 4,211,771 generally matters in two ways:
- Historical enforceability: it may be expired in most scenarios by now, depending on filing/maintenance timelines and whether any extensions existed.
- Citation and claim interpretation legacy: it still can appear in prosecution history, claim construction debates, and as prior art for later filings.
What is the likely prior-art and citation footprint?
In US prosecution and later litigation, an older issued patent like US 4,211,771 becomes prior art for:
- New compound claims that are not clearly distinguishable by structural or functional differences
- New use claims unless they are properly supported by later-discovered distinctions
- New formulation claims if they rely on the same core compound and use-case
In the US, patent landscape analytics usually treat such documents as:
- Baseline structural prior art for scaffold claims
- Baseline use/practical application prior art when indication wording is shared
How to map US 4,211,771 against the modern “patentability drivers” in the US
Chemical claims: novelty and non-obviousness
Post-1980 exam practice focuses on:
- Whether a later compound claim is structurally distinguishable (substituent changes that create new properties can matter)
- Whether the scaffold and substitution plan are obvious in light of earlier disclosures, including patents like US 4,211,771
Method-of-use claims: utility and specificity
Method claims face:
- Indication limits: narrow disease wording can preserve enforceability
- Enablement and written description: whether the patent text supports the specific therapeutic effect
Composition claims: formulation boundaries
Composition claims often pivot on:
- Whether the carrier/formulation is novel or routine
- Whether the claims recite any non-standard formulation components that improve stability, bioavailability, or dosing reliability
Where does US 4,211,771 land in the “core vs peripheral” IP stack?
Relative to typical IP portfolios, US 4,211,771 functions as:
- Core IP: protects the active ingredient (or a definable chemical family) and its therapeutic use
- Peripheral IP only if it includes narrowly defined formulation embodiments (most foundation patents from this era do not, unless the claims explicitly restrict excipient classes or delivery form)
That means later portfolio strength usually comes from:
- New chemical entities or expanded genera
- Formulations that improve PK/PD or patient convenience
- Combination therapy claims
US 4,211,771 in the US patent timeline (what you can infer operationally)
| Item |
Data |
| Patent |
US 4,211,771 |
| Grant date |
Jul. 8, 1980 |
| Legal role in landscape |
Foundational compound/composition/use patent (pre-1980s follow-on patterns) |
| Practical landscape function today |
Prior-art and historical scope benchmark; usually not a live exclusivity asset in most cases |
Key Takeaways
- US 4,211,771 is a foundational US drug patent with claim scope centered on a defined active compound, associated pharmaceutical compositions, and therapeutic use language.
- Its enforceable reach in a competitor analysis typically tracks three axes: compound coverage, salt/composition breadth, and indication wording in method/use claims.
- In the broader US drug-patent landscape, it functions mainly as a structural and use prior-art anchor for later filings and a reference point for how examiners and later courts interpret similar claim patterns.
FAQs
What claim types should I expect in US 4,211,771?
You should expect compound, pharmaceutical composition, and method-of-treatment/use style claims typical of issued chemical drug patents from this period.
Does US 4,211,771 likely cover salts or only the base compound?
Most composition/use drug patents from this era include pharmaceutically acceptable salts in claim scope where described; the breadth depends on the exact claim wording.
How does an older compound patent affect freedom-to-operate today?
Typically it affects prior-art positioning and can constrain later patentability, but it may not constrain current commercialization if it is expired.
What’s the easiest design-around against a foundational drug patent like this?
The most common routes are moving outside the claimed chemical definition, changing to unclaimed solid forms/formulations if not captured, and avoiding the claimed therapeutic use language.
What is the biggest lever for competitors: chemistry or indication?
Often indication wording and compound definition boundaries are the dominant levers because they determine whether small changes still read on the independent claims.
References (APA)
[1] United States Patent and Trademark Office. (1980). US 4,211,771 (Jul. 8, 1980). USPTO Patent Full-Text and Image Database.
