US Patent 11,077,098: Scope, Claim Strength, and US Landscape for the Salt of a (9R)-Oxaspiro Amine
US Patent 11,077,098 claims a tightly defined drug substance class: a pharmaceutically acceptable salt of a specific (9R)-oxaspiro[4.5]decan-9-yl pyridinyl amine bearing a (3-methoxythiophen-2-yl)methyl substituent. The enforceable scope expands from (i) salt identity into (ii) composition with carriers, into (iii) pain-treatment methods, and narrows at the high end with fumarate and high enantiomeric excess (ee) thresholds.
The practical outcome for freedom-to-operate (FTO) is straightforward: the patent is most likely to block commercialization of the same active as a pharmaceutically acceptable salt (especially fumarate), and to raise litigation risk for pain indications where the product uses that exact salt or an equivalent formulation falling within ee ranges claimed.
What is the claim scope of US 11,077,098?
Core active ingredient definition (claims 1-3)
Claim 1 defines the compound family as a salt of:
Claim 1 then limits the salt to:
- “a pharmaceutically acceptable salt” that is non-toxic
- and that the counterion is a non-toxic inorganic or organic acid salt
Claim 2 adds an extensive explicit list of salts (representative breadth across common pharmaceutically acceptable counterions). The listed salts include, among others:
- 2-hydroxyethanesulfonate
- 2-acetoxybenzoate
- acetate
- ascorbate
- benzenesulfonate
- benzoate
- bicarbonate
- carbonate
- citricate
- edetic acid (EDTA) salt
- fumarate
- glucoheptonate
- gluconate
- glutamate
- glycolate
- glycollyarsanilate
- hydrabamate
- hydrobromide
- hydrocloride
- hydroiodide
- hydroxymaleate
- isethionate
- lactate
- lactobionate
- laurylsulfonate
- maleate
- malate
- mandelate
- methanesulfonate
- napsylate
- nitrate
- oxalate
- pamoate
- pantothenate
- phenyl acetate
- phosphate
- propionate
- salicylate
- stearate
- subacetate
- succinate
- sulfamate
- sulfanilate
- sulfate
- tannate
- tartrate
- toluene sulfonate
(These appear verbatim as claim-2 enumerations in the claims provided.)
Claim 3 specifically narrows to:
Composition claims (claims 4-10)
Claims 4-6 cover pharmaceutical compositions containing:
- the salt of claim 1, or claim 2, or claim 3
- plus a pharmaceutically acceptable carrier or excipient
Claims 7-10 add formulation limitation tied to enantiomeric excess for the fumarate:
- Claim 7: ≥ 90% ee of the fumarate
- Claim 8: ≥ 95% ee
- Claim 9: ≥ 98% ee
- Claim 10: ≥ 99% ee
This matters because it creates a graded enforcement surface: a product at 97% ee can be inside one claim band but may fall outside another, depending on how the product’s ee is defined and measured.
Method of treatment claims (claims 11-20)
Claims 11-17 are pain-treatment methods using the compositions:
- Claim 11: using composition of claim 4
- Claim 12: using composition of claim 5
- Claim 13: using composition of claim 6
- Claim 14-17: using claim 6 compositions with fumarate ee thresholds (claims 7-10)
Claims 18-20 are pain-treatment methods using the salts:
- claim 1 salt
- claim 2 salt list (broad salt set)
- claim 3 fumarate salt
Key structural point: the patent ties treatment to “pain” without tying to a mechanism, receptor, route, dosing regimen, or patient subpopulation. This expands the likely read-through risk for common oral/systemic pain regimens.
How broad is claim 2 versus claim 3 (fumarate)?
Claim 2 is a belt-and-suspenders list: it enumerates many specific counterions and still keeps the base definition consistent with claim 1’s active ingredient. Claim 3 then isolates fumarate for higher-precision enforcement via composition and ee claims.
A practical scope matrix:
| Layer |
Claim set |
What changes |
Enforcement posture |
| Drug substance (salt identity) |
Claims 1-2 |
Counterion varies across non-toxic inorganic/organic acids and explicit salts |
Broad read across salt selection |
| Drug substance (single counterion) |
Claim 3 |
Fixes counterion to fumarate |
Highest clarity on infringement |
| Formulation |
Claims 4-6 |
Adds carrier/excipient |
Usually easy to satisfy if salt is present |
| Formulation (fumarate ee) |
Claims 7-10 |
Adds minimum ee (90 to 99%) |
Litigation risk increases with ee purity |
| Indication (pain) |
Claims 11-17 and 18-20 |
Uses composition/salt for pain treatment |
Blocks method use in “pain” unless designed around |
Where is the patent strongest for FTO?
1) The fumarate track is the highest specificity
Fumarate is explicitly claimed in:
- claim 3 (salt identity)
- claims 6-10 (composition with carrier and ee thresholds)
- claims 13-17 (pain-treatment methods using those compositions)
Fumarate is likely to be the commercialization candidate with the tightest control over physical properties, stability, and manufacturability, which means the product is more likely to match the claimed salt and ee band.
2) The ee ladder can create narrow carve-outs, but only if ee is actually controlled
If a competitor product uses the same fumarate but at, for example, 89% ee, it can fall outside claim 7’s ≥90% threshold while still potentially being captured by claims 3, 6, 13, or the broader pain method claims depending on how the product aligns with the composition language used in each claim.
If a competitor product uses non-fumarate salts, the ee claims generally do not apply, but claim 1 or claim 2 substance-level and method claims still do.
3) “Pain” is broad and does not require a specific protocol
There is no requirement in the claim text you provided for:
- neuropathic vs nociceptive labeling
- chronic vs acute
- route (oral, transdermal, etc.)
- dosing interval
- co-therapy
For FTO, this means the indication can be triggered by how the product is positioned and used, not by how it is dosed in a technically distinct protocol.
What claims are most likely to be asserted in litigation?
In most enforcement strategies, the starting points are usually the narrowest and cleanest matches:
1) Claim 3 + Claim 18/20-style method language (fumarate salt and pain treatment)
2) Claim 6/13/14-17 where ee is tested and aligned
3) If ee is disputed or not met, pivot to claim 1/2 scope over other salt forms
The reason is evidentiary: salt identity and ee measurement can be directly tested on batches, and method-of-use hinges on labeling, prescribing, and/or instructions for “pain.”
How does the claim language treat “salt equivalents” and designer salts?
The claims are written to capture:
- salts that are pharmaceutically acceptable and non-toxic
- within the broad class of inorganic/organic acid salts (claim 1)
- and a long enumerated list of specific acid salts (claim 2)
What is not claimed (based on your claim text):
- “hydrates,” “solvates,” “polymorphs,” “co-crystals” (no direct mention in claims provided)
- “free base” (claim 1 and others are salt-specific)
So if a competitor changes the solid form (polymorph or hydrate) without changing the salt type, claim risk remains. If a competitor avoids salts entirely and markets the free base, claim coverage in the provided claims may not directly attach, but that would depend on whether other unprovided claims exist in the patent (not provided here).
What is the US patent landscape around US 11,077,098?
A complete US landscape requires:
- listing the assignee and application family
- identifying related filings and continuations
- mapping any Orange Book entries for the active
- cross-referencing examiner citations, US patents, and WO publications
None of that metadata is available in the prompt you provided. Under the operating constraint here, a landscape statement without those sourced identifiers would be incomplete and not patent-analyst-grade.
What would an investor or R&D team do with this scope?
1) If you are developing the same active
Treat fumarate and high-tee fumarate as the primary infringement risk. Product development should track:
- whether the salt is fumarate or another member of the claim-2 set
- what ee range is used and how it is measured (ee claims are threshold-based)
2) If you are developing a competing salt
Because claim 2 enumerates many counterions and claim 1 covers non-toxic inorganic/organic acid salts more generally, “just change the counterion” is not a safe design-around unless the alternative is outside:
- pharmaceutically acceptable non-toxic inorganic/organic acid salts, or
- the enumerated list in claim 2, and also avoids capture by claim 1’s general language.
3) If you are developing for pain
Method claims are present. Even if the formulation is slightly different, if the label and use target “pain,” the method-of-treatment claims can still be implicated.
Claim-by-claim scope summary
| Claim |
Category |
What it covers |
Key limitation(s) |
| 1 |
Substance |
Salt of the specific (9R) oxaspiro amine |
Non-toxic inorganic/organic acid salt |
| 2 |
Substance |
Salt of claim 1 limited to enumerated salts |
Specific counterion list |
| 3 |
Substance |
Fumarate salt |
Counterion = fumarate |
| 4 |
Composition |
Claim-1 salt + carrier/excipient |
General |
| 5 |
Composition |
Claim-2 salt + carrier/excipient |
Enumerated salt set |
| 6 |
Composition |
Claim-3 fumarate + carrier/excipient |
Fumarate |
| 7 |
Composition |
Claim-6 composition |
Fumarate ee ≥ 90% |
| 8 |
Composition |
Claim-6 composition |
Fumarate ee ≥ 95% |
| 9 |
Composition |
Claim-6 composition |
Fumarate ee ≥ 98% |
| 10 |
Composition |
Claim-6 composition |
Fumarate ee ≥ 99% |
| 11 |
Method |
Treat pain by administering claim-4 composition |
Pain indication |
| 12 |
Method |
Treat pain by administering claim-5 composition |
Pain indication |
| 13 |
Method |
Treat pain by administering claim-6 composition |
Pain indication |
| 14 |
Method |
Treat pain by administering claim-7 composition |
Fumarate ee ≥ 90% |
| 15 |
Method |
Treat pain by administering claim-8 composition |
Fumarate ee ≥ 95% |
| 16 |
Method |
Treat pain by administering claim-9 composition |
Fumarate ee ≥ 98% |
| 17 |
Method |
Treat pain by administering claim-10 composition |
Fumarate ee ≥ 99% |
| 18 |
Method |
Treat pain by administering claim-1 salt |
Pain indication |
| 19 |
Method |
Treat pain by administering claim-2 salt |
Pain indication |
| 20 |
Method |
Treat pain by administering claim-3 fumarate salt |
Pain indication |
Key Takeaways
- US 11,077,098 is salt-centric: enforceable scope is anchored on a single active scaffold with an explicit (9R) stereochemical definition and then expands by pharmaceutically acceptable acid salt selection.
- Fumarate is the main enforcement hook because it is singled out (claim 3) and then tied to composition and pain methods with ee thresholds (90%, 95%, 98%, 99%).
- “Pain” method claims are broad in the claim text you supplied and do not require dose, route, regimen, or patient subgroup constraints.
- A meaningful US patent landscape cannot be produced from the claim text alone; the landscape requires assignee, family, publication/app numbers, and Orange Book/device details to map related patents and expiry timelines.
FAQs
1) Does the patent require fumarate to be infringed?
No. Claims 1 and 2 cover pharmaceutically acceptable non-toxic inorganic or organic acid salts of the same (9R) active, while claim 3 covers fumarate specifically.
2) What is the practical impact of the ee thresholds?
They create different infringement bands for fumarate-containing compositions: products at or above 90%, 95%, 98%, or 99% ee map to claims 7-10 and corresponding pain method claims 14-17.
3) Is “pain” defined more narrowly in the claims provided?
No. The claim text provided states “treating pain” without further sub-classification.
4) Do the composition claims add meaningful design-around options?
Not much if your product uses the same salt with standard pharmaceutically acceptable carriers, because claims 4-6 and 13-17 are satisfied by conventional formulation.
5) Can switching to another salt avoid the patent?
Claim 1 is broad over non-toxic inorganic/organic acid salts, and claim 2 enumerates many specific counterions. Avoidance requires careful selection outside both the general claim 1 class and the claim 2 list, plus an indication/use strategy that avoids the pain method claims.
References
[1] US Patent 11,077,098 (claims provided in prompt).
