Scope and patent landscape of US Patent 8,183,274 (method claims for prostate cancer and related indications)
US 8,183,274 is a US utility patent that claims broad therapeutic method-of-treatment coverage for prostate cancer, benign prostate hyperplasia, breast cancer, and ovarian cancer. The independent claim is a generic “method for treating” format with a compound-selected-from-a-group limitation, then a broad set of dependent claims that tighten dosing ranges, plasma concentration targets, dosing frequency, administration routes, dosage forms, and carrier/diluent components. The practical enforcement risk is highest for any US product or clinical regimen that (i) uses the claimed compound(s) within the stated exposure and/or dose bands and (ii) targets the claimed tumor indications (especially prostate cancer subtypes).
What does US Patent 8,183,274 claim and what is the practical scope?
Short answer: The patent claims method-of-treatment uses of a specific “compound selected from the group consisting of…” (not provided in your excerpt) for multiple hormone/epithelial cancer indications and BPH, with dosing, route, dosage form, and PK exposure constraints in dependent claims.
Claim architecture (how breadth is created)
Claim 1 is the broadest hook:
- A method for treating prostate cancer
- by administering a therapeutically effective amount of a compound selected from a group (or a pharmaceutically acceptable salt)
- thereby treating the prostate cancer
This is classic method-of-use claim drafting that captures:
- therapeutic regimens that do not specify exact dose or exposure, as long as they fall under “therapeutically effective amount” and use the claimed compound(s).
Claims 2–5 create dose-range tiers:
- broad range: about 0.001 to 100 mg/kg/day (Claim 2)
- intermediate ranges: 1–10 mg/kg/day (Claim 3) and 0.1–10 mg/kg/day (Claim 4)
- a single-point dose: about 1 mg/kg/day (Claim 5)
Claims 6 and 11 split prostate cancer by biology:
- “hormone refractory prostate cancer” (Claim 6)
- “hormone sensitive prostate cancer” (Claim 11)
Claim 7 sets route-of-administration optionality:
- intravenous injection, injection into tissue, intraperitoneally, orally, topically, nasally
Claims 8–10 narrow to oral and dosage form families:
- oral administration (Claim 8)
- dosage forms: solution, dispersion, suspension, powder, capsule, tablet, pill, and time release forms (Claim 9)
- capsule/tablet/pill (Claim 10)
Claims 13–14 add formulation carrier specifics:
- administered with a pharmaceutically acceptable carrier or diluent
- carrier includes DMSO, PEG, and water (Claim 14)
Claims 15–24 create PK/exposure and unit-dose constraints:
- specific dose point: 2 mg/kg/day (Claim 15)
- peak plasma concentration target windows:
- 0.5 to 75 μM (Claim 16)
- about 10 μM (Claim 17)
- steady-state plasma concentration windows:
- 5 to 100 μM (Claim 18)
- 10 to 50 μM (Claim 19)
- about 25 μM (Claim 20)
- dosing frequency:
- daily (Claim 21)
- three times per day (Claim 22)
- unit dosage form amount:
- 5 to 1000 mg per unit (Claim 23)
- about 100 mg per unit (Claim 24)
Claims 25–40 expand indication coverage:
- Claim 25: method for treating benign prostate hyperplasia
- Claims 31–32: hormone sensitive and hormone refractory prostate cancer are again referenced (depending on the drafting chain in claims 25+ excerpts)
- Claim 33: breast cancer
- Claim 37: ovarian cancer
- Claims 26–30, 34–36, 38–40 are listed as blank in your excerpt, but they clearly exist as further dependent claim layers (the excerpt does not show their text).
Where the “compound group” matters
Every claim depends on the phrase:
- “a compound selected from the group consisting of [not shown in excerpt] or a pharmaceutically acceptable salt thereof”
Without the member(s) of the group, the legal scope can still be assessed structurally, but compound-specific infringement mapping cannot be made from your excerpt alone. The scope described below therefore applies to any method using the claimed group member(s).
Which prostate cancer subpopulations and treatment modalities are covered?
Short answer: Both hormone sensitive and hormone refractory prostate cancer are explicitly claimed, with open route-of-administration options and dependent claims that constrain PK exposure, dose, frequency, carrier, and dosage form.
Prostate cancer subtypes
- Hormone refractory: Claim 6 and referenced again in the prostate cancer chain tied to dependent claims (Claim 31)
- Hormone sensitive: Claim 11 and referenced again in the prostate cancer chain tied to dependent claims (Claim 32)
Route and dosing schedule levers
The claim set gives multiple infringement “paths”:
- Route: Claim 7 includes oral and non-oral routes (IV, tissue injection, IP, topical, nasal)
- Oral: Claim 8 is a dependent narrowing
- Frequency: daily (Claim 21) and TID (Claim 22)
- PK: peak and steady-state concentration windows (Claims 16–20)
Formulation and carrier constraints
Two layers exist:
- dosage-form families (Claims 9–10)
- carrier/diluent specifics (Claim 13–14):
- includes DMSO, PEG, and water as part of the carrier/diluent
For litigation, carrier language can become a major design-around focal point because many formulations use different solubilizers.
What dosing ranges and PK windows define infringement risk?
Short answer: The patent provides multiple dependent claims with numeric dosing and plasma concentration windows. Regimens that hit those exposures and/or dose bands using the claimed compound group member(s) have the highest infringement risk.
Dosing bands in mg/kg/day
- 0.001–100 mg/kg/day (Claim 2)
- 1–10 mg/kg/day (Claim 3)
- 0.1–10 mg/kg/day (Claim 4)
- 1 mg/kg/day (Claim 5)
- 2 mg/kg/day (Claim 15)
PK windows in μM
- Peak plasma concentration:
- 0.5–75 μM (Claim 16)
- about 10 μM (Claim 17)
- Steady-state plasma concentration:
- 5–100 μM (Claim 18)
- 10–50 μM (Claim 19)
- about 25 μM (Claim 20)
Unit dosage form amount
- 5–1000 mg active ingredient per unit dosage form (Claim 23)
- about 100 mg per unit dosage form (Claim 24)
Key enforcement takeaway
Even if a product deviates from one dependent claim constraint, the independent Claim 1 still captures:
- “therapeutically effective amount” treatment of prostate cancer with the claimed compound group member(s)
Dependent numeric constraints mainly raise the chance of proving infringement with clinical PK/dosing data rather than only general therapeutic effect.
Does US 8,183,274 cover benign prostate hyperplasia, breast cancer, and ovarian cancer?
Short answer: Yes. The patent includes separate “method for treating” claims for benign prostate hyperplasia, breast cancer, and ovarian cancer, each using the same “therapeutically effective amount” of the claimed compound group.
Indication list from the excerpt
- Prostate cancer (independent Claim 1)
- Benign prostate hyperplasia (Claim 25)
- Breast cancer (Claim 33)
- Ovarian cancer (Claim 37)
Claim linkage mechanics
- Claims 25–32 show BPH as its own method claim and re-mention prostate cancer hormone sensitivity/refractoriness in dependent structure.
- Claims 33–36 and 37–40 similarly likely reuse the same dependent constraint set (dose ranges, route, dosage forms, PK, etc.), but your excerpt does not display the omitted claim text for claims 26–30 and 34–36 and 38–40.
How strong is the patent estate implied by these claim types?
Short answer: The estate is structurally strong because it mixes broad method coverage (therapeutically effective amount) with multiple dependent constraints that allow infringement proof from clinical/regimen evidence.
Strength factors
- Independent method claim breadth
- Claim 1 is indication-specific (prostate cancer) and does not require numeric dose or PK in the independent claim as excerpted.
- Dependent claim multiplicity
- Multiple dependent claims provide alternative routes to infringement: specific dose points, dose windows, frequency, route, dosage form, and PK targets.
- Formulation carrier specificity
- The DMSO/PEG/water carrier claim can restrict generics or reformulations that change excipient systems.
Weakness factors (what commonly narrows enforceability)
- Numeric PK and dose dependent claims can be easier to avoid by changing exposure, schedule, or dosing strategy, while the independent claim remains broader.
- Any future validity challenge would likely target claim clarity, written description, and enablement relative to the wide range of dosing and the broad indication set, but such outcomes depend on the specification text, which is not provided.
What patent scope is most at risk for design-around?
Short answer: Regimens that keep the claimed compound’s exposure within the claimed peak and steady-state windows and maintain the route/dosing frequency and, where relevant, the DMSO/PEG/water carrier are high-risk. Using different excipients or changing dosing to miss the PK windows reduces risk only for the dependent claims; Claim 1 may still capture “therapeutically effective amount” treatment.
Highest-risk “matching” features
- Same compound group member(s)
- Prostate cancer indication (including hormone sensitive and hormone refractory subsets)
- Dose in the overlapping ranges and/or exact points (1 mg/kg/day or 2 mg/kg/day)
- Peak/steady-state concentrations in the stated windows (Claims 16–20)
- Frequency daily or three times per day
- Route matches oral or included injection modes
- Carrier contains DMSO, PEG, water (if asserting dependent Claims 13–14)
Likely design-around levers
- Reformulate with a non-DMSO/non-PEG carrier system (to evade Claim 14 dependent language)
- Adjust dosing schedule or exposure to avoid the numeric PK windows (to evade dependent Claims 16–20)
- Change route if clinical strategy uses a route not aligned with the asserted dependent route claims (though Claim 7 broadly includes most common routes)
How would a generic or biosimilar-style challenge map to these claims?
Short answer: This is a small-molecule method claim set, so the main competitive risk is “skinny labeling” and Paragraph IV theory built around whether the proposed product is used in a way that infringes Claim 1 or specific dependent claims.
Paragraph IV and labeling strategy implications
- Method claims can be triggered by actual “use” of the drug in the claimed way, not by the label alone in many jurisdictions, depending on enforcement posture and the specific claim interpretation.
- A typical defensive strategy would attempt to eliminate instructions that induce the infringing method of use: prostate cancer dosing regimens aligned to the numeric PK targets and specific dosing frequency or carrier.
Clinical evidence matters
Numeric dependent claims (dose and PK) are typically proved with:
- clinical PK data
- dosing regimen records
- measured or modeled concentrations
That creates evidentiary friction for generic entrants and can increase settlement leverage for the patent holder.
US 8,183,274 expiration and exclusivity timeline: what drives it?
Short answer: Without the patent’s filing/priority data, terminal disclaimer status, and any patent term adjustments, an exact expiration date cannot be derived from the excerpt alone.
What typically governs patent expiry for US method patents
- Utility patent term: usually 20 years from the earliest effective non-provisional filing date subject to adjustments
- Patent term adjustment (PTA)
- Terminal disclaimers
- Changes in claims through continuation/prosecution history (not provided)
Litigation and Orange Book status: what can be concluded from the excerpt?
Short answer: The excerpt does not identify the active ingredient(s) in the “compound selected from the group,” nor does it provide associated FDA application references. Therefore, Orange Book listing, exclusivity periods, and Paragraph IV litigation mapping cannot be executed from the provided content.
Comparison: what claim scope changes if the “compound group” is narrow vs broad?
Short answer: If the compound group contains a single chemical entity, infringement is easier to map. If the group contains multiple members, the claim covers a wider set of actives and salts, increasing the blocking effect against alternative chemistry.
Practical impacts for enforcement
- Narrow group: fewer potential infringing products, more focused licensing or settlements
- Broad group: more potential infringing products, stronger deterrent against close analogs if the compounds fall within the defined group
Key tables: claim feature matrix for infringement mapping
Claim feature matrix (from your excerpt)
| Claim |
Disease / target |
Key limitation type |
Numeric/structural constraint in excerpt |
| 1 |
Prostate cancer |
Method of treatment |
“therapeutically effective amount” of claimed compound group (or salt) |
| 2 |
Prostate cancer |
Dose band |
0.001–100 mg/kg/day |
| 3 |
Prostate cancer |
Dose band |
1–10 mg/kg/day |
| 4 |
Prostate cancer |
Dose band |
0.1–10 mg/kg/day |
| 5 |
Prostate cancer |
Dose point |
about 1 mg/kg/day |
| 6 |
Prostate cancer |
Subtype |
hormone refractory |
| 7 |
Prostate cancer |
Administration route |
IV, tissue injection, IP, oral, topical, nasal |
| 8 |
Prostate cancer |
Route narrowing |
oral |
| 9 |
Prostate cancer |
Dosage form family |
solution, dispersion, suspension, powder, capsule, tablet, pill, time-release capsule/tablet/pill |
| 10 |
Prostate cancer |
Dosage form narrowing |
capsule/tablet/pill |
| 11 |
Prostate cancer |
Subtype |
hormone sensitive |
| 13 |
Prostate cancer |
Formulation carrier |
pharmaceutically acceptable carrier/diluent |
| 14 |
Prostate cancer |
Carrier composition |
includes DMSO, PEG, water |
| 15 |
Prostate cancer |
Dose point |
about 2 mg/kg/day |
| 16 |
Prostate cancer |
PK peak window |
0.5–75 μM peak |
| 17 |
Prostate cancer |
PK peak point |
about 10 μM peak |
| 18 |
Prostate cancer |
PK steady-state window |
5–100 μM steady-state |
| 19 |
Prostate cancer |
PK steady-state window |
10–50 μM steady-state |
| 20 |
Prostate cancer |
PK steady-state point |
about 25 μM steady-state |
| 21 |
Prostate cancer |
Frequency |
daily |
| 22 |
Prostate cancer |
Frequency |
three times per day |
| 23 |
Prostate cancer |
Unit dose amount |
5–1000 mg per unit |
| 24 |
Prostate cancer |
Unit dose point |
about 100 mg per unit |
| 25 |
Benign prostate hyperplasia |
Method of treatment |
therapeutically effective amount of claimed compound group |
| 33 |
Breast cancer |
Method of treatment |
therapeutically effective amount of claimed compound group |
| 37 |
Ovarian cancer |
Method of treatment |
therapeutically effective amount of claimed compound group |
What do these claim choices imply for licensing and settlement leverage?
Short answer: The independent prostate cancer method claim combined with multiple dependent numeric constraints typically supports strong settlement leverage. The patent holder can threaten a broad “therapeutically effective amount” infringement theory (Claim 1) and add evidentiary support via dependent dose/PK claims using clinical data.
Settlement leverage points
- Dose and PK ranges create “objective” comparison benchmarks
- Dosing frequency and dosage forms make it harder to argue incidental use
- Carrier composition adds a formulation-specific argument
Key Takeaways
- US 8,183,274 is a method-of-treatment patent with an independent broad prostate cancer claim (Claim 1) and multiple dependent claims that specify dose ranges, dose points, peak and steady-state plasma concentration windows, dosing frequency, routes, dosage forms, and carrier composition (DMSO/PEG/water).
- The patent also claims methods for benign prostate hyperplasia, breast cancer, and ovarian cancer using the same claimed compound group.
- Enforcement risk is highest where a US regimen:
- uses the claimed compound group member(s),
- treats prostate cancer (including hormone sensitive and hormone refractory),
- and matches one or more of the dependent constraints (dose, PK, frequency, dosage form, or carrier).
- Any assessment of Orange Book status, specific generic entry paths, and litigation posture cannot be completed from the excerpt because the identity of the claimed “compound group” and FDA linkage data are not provided.
FAQs
- How do numeric PK-dependent claims (peak and steady-state μM) change infringement proof for method-of-treatment patents?
- What design-around most effectively avoids formulation-dependent carrier claims like DMSO/PEG/water?
- Do method-of-use claims for prostate cancer attach to clinical practice even if labeling omits prostate cancer instructions?
- How do overlapping mg/kg dosing ranges create “inevitable coverage” if generic entrants match approved dosing schedules?
- When a patent claims multiple indications (prostate cancer, BPH, breast, ovarian), how does that affect licensing scope and settlement value?
References
- United States Patent 8,183,274 (claims excerpt provided in prompt).
