Scope and Claims of US Patent 6,369,062 (Ranolazine Compressed Tablet) and the US Patent Landscape
US Patent 6,369,062 claims a specific composition and dose window for a ranolazine compressed tablet built around (i) a high ranolazine loading, (ii) methacrylic-acid copolymer as the key polymeric matrix component, and (iii) a defined set of optional/excipient components including hydroxypropyl methylcellulose (HPMC), microcrystalline cellulose, sodium hydroxide, and magnesium stearate. The scope is composition-limited: it does not claim manufacturing steps, separate dosage forms, or alternative polymer grades in the text provided. The practical freedom-to-operate for generics hinges on staying outside the claimed weight ranges, the claimed excipient set (as recited), and the claimed ranolazine amount range per tablet (350 to 800 mg).
What is US Patent 6,369,062 claim scope for a ranolazine compressed tablet “consisting essentially of”?
Core claim 1 elements (as provided):
- Dosage form: compressed tablet.
- Composition transition: “consisting essentially of” a defined package of materials.
- Active: ranolazine at ~70 to ~80 wt%.
- Polymer matrix: methacrylic acid copolymer at ~5 to ~12.5 wt%.
- Additional excipients: ~1 to ~3 wt% of hydroxypropyl methylcellulose, microcrystalline cellulose, sodium hydroxide, and magnesium sterate (all recited within this range).
- Absolute dose: tablet includes ~350 to ~800 mg ranolazine.
“Consisting essentially of” meaning for design-around
“Consisting essentially of” typically allows additional components that do not materially affect basic and novel characteristics of the claimed invention. As drafted, the claim’s basic characteristics appear to be (a) very high ranolazine loading, (b) a methacrylic-acid copolymer content window, and (c) a limited excipient package plus a specific ranolazine mg-per-tablet range. A generic or licensee that introduces additional excipients that change release profile, tablet mechanics, or solubility behavior could be treated as outside the scope, depending on claim construction and evidence in prosecution or litigation record.
Scope boundary conditions that matter most
For FTO and licensing, the biggest “tripwires” are the numerical ranges and the absolute ranolazine mg per tablet:
- Ranola zine wt% (70 to 80 wt%)
A formulation at 69 wt% is outside the literal wt% floor. A formulation at 81 wt% is outside the literal wt% ceiling.
- Methacrylic acid copolymer wt% (5 to 12.5 wt%)
Polymer content is the principal driver for extended-release behavior in many ranolazine products; staying outside the range is a clean design-around if other attributes permit.
- Excipient package recited within 1 to 3 wt%
The claim language you provided ties hydroxypropyl methylcellulose, microcrystalline cellulose, sodium hydroxide, and magnesium stearate into the stated excipient weight band. If the accused product omits one of these materials, it may fall outside literal scope, unless “consisting essentially of” construction and infringement arguments treat some excipients as optional or implicit.
- Ranola zine mg per tablet (350 to 800 mg)
This is an absolute dose limit that can defeat “same composition, different strength” arguments. A 250 mg tablet would not fall inside the literal mg window.
How do the numeric ranges translate into formulation design constraints?
wt% and mg-per-tablet interplay
The claim links both concentration (wt%) and absolute dose. That combination restricts possible tablet weights.
If ranolazine is 70–80 wt% and is present as 350–800 mg per tablet:
- At 70 wt%, tablet mass is approximately 500–1143 mg total (because 350 mg ranolazine corresponds to 500 mg total; 800 mg corresponds to 1143 mg total).
- At 80 wt%, tablet mass is approximately 438–1000 mg total (350/0.80 = 438 mg; 800/0.80 = 1000 mg).
So, any generic attempting to hit the same tablet weight while changing strengths must still keep both the wt% and mg-per-tablet windows aligned.
Polymer and excipient windows constrain matrix and processing
Methacrylic-acid copolymer at 5–12.5 wt% is a relatively narrow window for extended-release matrices. For a tablet in the mid-range (say 700 mg ranolazine), polymer would be roughly 35–87.5 mg per tablet at 5–12.5 wt%. That is a measurable and testable feature.
For excipients in the “1 to 3 wt%” band, total excipient mass for the recited set would be small compared to the drug and polymer. This affects mechanical strength and disintegration characteristics and can drive process differences.
Practical claim construction pressure points
In litigation, disputes typically turn on:
- Whether a proposed formulation’s wt% values overlap under test variability.
- Whether the formulation uses the same polymer type (methacrylic acid copolymer could encompass multiple commercial grades).
- Whether the excipient package includes all recited materials, or whether some are optional in a “consisting essentially of” sense.
What patents protect ranolazine compressed tablets in the US beyond US 6,369,062?
Because you provided only claim text, a complete US landscape requires specific bibliographic and family data that is not included in your prompt. Without the patent’s application number, assignee, filing date, priority data, and confirmed claim set, a full chart of related US patents, continuations, and Orange Book listings cannot be produced accurately.
What can be concluded from the claim itself:
Patent estate themes likely present around this claim type
Ranolazine tablet portfolios in the US typically cluster into three patent themes relevant to composition claims like 6,369,062:
- Composition claims (wt% active, polymer, and excipient windows).
- Release mechanism claims (matrix design and polymer grades).
- Manufacturing or process claims (granulation, compression, coating, or microencapsulation).
US 6,369,062, as stated, is a composition claim directed to a specific high-loading matrix tablet and is therefore best read as blocking a “matching recipe” approach: ranolazine 70–80 wt%, methacrylic acid copolymer 5–12.5 wt%, and the recited excipient set in 1–3 wt% with 350–800 mg ranolazine per tablet.
Adjacent claim coverage that may exist in continuation patents
The phrase “consisting essentially of” and the explicit numeric windows suggest that the family likely includes other claims with:
- shifted wt% boundaries,
- alternative excipient selections (still with the same polymer),
- different mg-per-tablet strengths,
- or claims focused on release profile testing tied to those compositions.
Without the patent family listing, any enumerated set of those continuations would be speculative.
When does US 6,369,062 lose exclusivity or patent protection?
A complete exclusivity timeline requires at least:
- filing date and any priority date(s),
- whether the patent is subject to PTA,
- whether there are regulatory exclusivities (Orange Book type),
- and whether there are terminal disclaimers.
No such dates are included in your prompt. Therefore, a reliable expiration/exclusivity timeline cannot be stated.
What Orange Book status would US 6,369,062 have for ranolazine tablet strengths?
Orange Book status depends on:
- the specific branded drug product,
- dosage form (extended-release vs other),
- and whether the listed patents cover the NDA/strength/formulation that falls inside the claimed mg window.
No NDA number, listed strength(s), or product linkage is provided, so a verified Orange Book mapping cannot be produced.
How would a generic design around claim 1 of US 6,369,062?
Based on the literal constraints in the claim text, design-around strategies that are structurally aligned with the claim boundaries are:
1) Move ranolazine wt% outside 70–80 wt%
- Use a formulation with ranolazine slightly below 70 wt% or above 80 wt%.
- This also shifts total tablet mass if the mg-per-tablet stays within the same range, so the design must account for both constraints.
2) Move methacrylic acid copolymer wt% outside 5–12.5 wt%
- Lower the polymer to below 5 wt% or raise it above 12.5 wt%.
- This can materially change release, but if the product aims for a different release profile, it may be viable.
3) Use a different polymer or polymer classification
Even if the excipient is “methacrylic acid copolymer” in a broad sense, the claim may be sensitive to the specific chemistry or grade. Switching to a non-methacrylic-acid polymer or to a copolymer outside the intended classification can avoid literal infringement.
4) Change the excipient package
The claim’s excipient set explicitly lists hydroxypropyl methylcellulose, microcrystalline cellulose, sodium hydroxide, and magnesium stearate within the 1–3 wt% band. A design that:
- omits at least one listed excipient, or
- replaces the listed excipient with a different functional excipient,
may avoid literal coverage, subject to “consisting essentially of” interpretation.
5) Offer a strength outside the 350–800 mg ranolazine per tablet window
If the claimed strengths are within 350–800 mg ranolazine per tablet, a generic launched at 250 mg ranolazine per tablet would not be within the mg-per-tablet limit as written.
What method-of-use, process, or formulation patents typically overlap with composition claims like this?
The claim you provided is not framed as a method-of-use patent. However, ranolazine brands often have separate patent layers for:
- dosing regimens,
- extended-release mechanism,
- stability/handling,
- manufacturing methods,
- and related salts/polymorphs.
Without the broader patent record, it cannot be determined whether those layers exist in the same estate as US 6,369,062.
What Paragraph IV challenges and litigation risks exist for US 6,369,062?
Litigation risk depends on:
- the NDA/strength tied to the patent,
- whether any ANDA(s) have been filed,
- whether Paragraph IV certifications have been made,
- and whether the patent is asserted in disputes.
No ANDA numbers, court filings, or settlement records are included in your prompt, so a litigation-specific answer cannot be produced.
Which companies are likely practicing the claimed formulation and challenging/defending the patent?
This requires identification of:
- the patent assignee,
- the branded product manufacturer,
- and any ANDA filers for ranolazine tablets.
No assignee or product linkage is provided in your prompt, so company-specific identification cannot be produced.
Key takeaways
- US 6,369,062 claim 1 is a composition-limited claim for a compressed ranolazine tablet with:
- 70–80 wt% ranolazine
- 5–12.5 wt% methacrylic acid copolymer
- 1–3 wt% recited excipients (hydroxypropyl methylcellulose, microcrystalline cellulose, sodium hydroxide, magnesium stearate)
- 350–800 mg ranolazine per tablet
- “consisting essentially of” constraining additional components.
- The most direct generic design-arounds are to break one of the three numeric pillars (ranolazine wt%, polymer wt%, excipient package, or the 350–800 mg dose window) or switch out the polymer category and/or the excipient set.
- A full US patent landscape (related continuations, Orange Book mappings, expiration dates, and litigation/Paragraph IV history) cannot be reliably compiled from claim text alone.
FAQs
- If a generic matches ranolazine wt% but misses the methacrylic acid copolymer wt% range, is it outside literal claim 1?
- Can a different tablet strength (e.g., 250 mg) avoid the “350 to 800 mg” ranolazine-per-tablet limitation even if wt% matches?
- How does “consisting essentially of” affect adding a release modifier not listed in the excipient set?
- Does swapping magnesium stearate for another lubricant preserve infringement risk under a composition claim?
- If a formulation uses a different methacrylic acid copolymer grade, how is literal scope typically assessed?
References
- US Patent 6,369,062, claim 1 (as provided in user prompt).
