Details for Patent: 6,479,496

United States Patent 6,479,496 (Method for Treating Variant and Exercise-Induced Angina Using High-Load, Sustained-Release Ranolazine)

What does US 6,479,496 claim, in enforceable terms?

US 6,479,496 is a method-of-treatment patent for human variant and exercise-induced angina using a sustained-release (SR) pharmaceutical dosage form that meets specific dose composition, tablet number, dosing frequency, and plasma exposure targets.

The independent claim (Claim 1) is structured around four enforceable elements:

1. Indication (patient population)

   • “variant and exercise-induced angina”

2. Product format

   • “sustained release pharmaceutical dosage form”
   • includes at least 50% by weight ranolazine
   • dose is “in no more than two tablets per dose”

3. Exposure target

   • maintains “ranolazine plasma levels… at a minimum of 850 ng base/mL for at least 24 hours”

4. Dosing schedule limitation

   • dose administered at a frequency selected from once, twice and three times over 24 hours

How broad is Claim 1 vs. the dependent narrowing claims?

Claim 1 sets the core scope; dependent claims tighten it via plasma ceiling, frequency subset, tablet packing geometry, composition ranges, pharmacokinetic (PK) smoothness, and dose amount.

Claim scope matrix (scope controls litigation and design-around)

Practical reading for infringement

• To infringe Claim 1, an accused SR ranolazine regimen must satisfy all of:

  • patient indication (variant and/or exercise-induced angina),
  • sustained release dosage form,
  • ≥50% by weight ranolazine,
  • ≤2 tablets per dose,
  • maintains plasma ≥850 ng base/mL for ≥24 hours,
  • administered once, twice, or three times per 24 hours.

• Dependent claims create narrower “fallback” positions:

  • Claim 2 adds a ceiling.
  • Claims 3 and 4 constrain frequency and tablet count per dose.
  • Claims 5 and 6 constrain ranolazine content by weight.
  • Claims 7 to 9 constrain peak-to-trough ratio (PK flattening).
  • Claim 10 constrains ranolazine amount per dose.

What is the enforceable “design space” the claims carve out?

Taken together, the claims define a relatively tight PK-and-formulation regime. The boundaries that matter for product development and freedom-to-operate (FTO) are:

Hard boundaries for Claim 1 (and thus easiest to litigate)

• Composition floor: ≥ 50% by weight ranolazine in the SR dosage form.
• Tablet cap: no more than two tablets per dose.
• Exposure minimum: plasma ≥ 850 ng base/mL for at least 24 hours.
• Dosing frequency: once, twice, or three times per 24 hours.
• Therapeutic context: treating variant and exercise-induced angina in a human.

Hard boundaries added by dependent claims

• Ceiling: maximum plasma ≈ 4000 ng base/mL (Claim 2).
• Frequency narrowing: once or twice per 24 hours (Claim 3).
• Tablet geometry: two doses/24 hours, each dose = two tablets (Claim 4).
• Composition band: 50% to 95% (Claim 5); 70% to 80% (Claim 6).
• PK smoothness:
  • peak/trough < 4:1 (Claim 7)
  • < 3:1 (Claim 8)
  • < 2:1 (Claim 9)
• Dose amount: 500 to 1500 mg ranolazine (Claim 10).

Claim construction implications: what parties will argue

Because the patent uses a mix of formulation composition and clinical PK targets, claim construction and expert testimony typically focus on these friction points:

1. “Sustained release”

   • The term is likely litigated against the specification’s dissolution/PK profile, because the claims tie sustained release to meeting the 24-hour plasma minimum.

2. “at least 50% by weight ranolazine”

   • In practice, disputes often hinge on what counts as the dosage form mass (core only vs. includes coating, excipients, shell, etc.).
   • For design-around, companies target lower ranolazine weight fraction (but must keep PK targets).

3. “no more than two tablets per dose”

   • This is a structural limitation. Changing tablet count per dose can avoid the independent claim if the regimen exceeds two tablets per dose, but then dosing frequency and PK must still satisfy the therapeutic requirements.

4. “maintain… at a minimum of 850 ng base/mL for at least 24 hours”

   • This is an objective PK metric.
   • Enforceability depends on how plasma samples are timed and what analytical method defines “ng base/mL.”

5. “frequency selected from once, twice and three times over 24 hours”

   • If a regimen is once daily, it fits; twice daily fits; three times daily fits.
   • If a regimen uses a different cadence (e.g., four times or every other schedule) it may fall outside, but most SR products are designed around once or twice daily.

6. Peak-to-trough ratio thresholds (Claims 7-9)

   • These are high-value fallback positions when Claim 1 is harder to prove, because PK ratios can be measured from profiles.

How does US 6,479,496 map to the competitive ranolazine SR landscape?

Without relying on unspecified patent-family context, the only defensible landscape claims are those directly implied by the claim language itself: the patent covers high ranolazine loading SR tablets with flattened PK sufficient to hold trough levels above 850 ng base/mL for 24 hours, with tablet number capped at two per dose.

Key implications for competitor products (high-level FTO lens)

To evaluate whether another SR ranolazine product infringes or avoids the patent, the technical question reduces to whether the product and prescribed regimen can meet the claim’s converging constraints:

• Formulation: ≥50% ranolazine by weight and SR release.
• Dosing: ≤2 tablets per dose with a dosing frequency among 1x, 2x, or 3x per day.
• PK: trough ≥850 ng base/mL across 24 hours; and if needed, peak-to-trough ratio below 4:1 (or 3:1, or 2:1 depending on fallback).
• Dose magnitude: 500-1500 mg ranolazine (Claim 10).

Design-around pathways suggested by the claim limits

These are the routes a developer typically explores because they attack independent-claim elements rather than dependent fallbacks:

• Reduce or eliminate the ≥50% by weight ranolazine property (but then must still meet the 850 ng base/mL trough target).
• Increase tablet count per dose beyond two (but then must still comply with other dosing frequency and PK constraints).
• Change dosing frequency away from once/twice/three times per 24 hours (less common for approved SR regimens).
• Target a PK profile that drops below 850 ng base/mL before 24 hours (but then may conflict with therapeutic goal).
• If exposure is achieved, but the developer wants to avoid dependent claims, adjust PK to push peak-to-trough above the relevant thresholds (4:1, 3:1, 2:1) or exceed maximum ~4000 ng base/mL. That often increases tolerability risk, so it is more a litigation defense than a safe development strategy.

Litigation posture: what is likely to matter in a claim chart

A typical infringement case under these claims will run as a checklist:

Claim 1 checklist

• Human patient: “variant and exercise-induced angina”
• Treatment method: “administering”
• Dosage form: “sustained release” SR tablet product
• Composition: ≥50% wt ranolazine
• Tablet count: ≤2 tablets per dose
• Frequency: once, twice, or three times over 24 hours
• PK profile:
  • Minimum trough ≥850 ng base/mL
  • Sustained for ≥24 hours

Dependent claims: what shifts the burden

• Claim 2 (max plasma ceiling near 4000 ng base/mL)
• Claim 5/6 (50-95% wt or 70-80% wt)
• Claims 7-9 (peak-to-trough <4:1, <3:1, <2:1)
• Claim 10 (500-1500 mg ranolazine per dose)

Patent landscape summary (scope-driven, claim-derived)

The landscape question is not answered by generalities because the claim language is the primary “landscape map.” Within that map:

Where the patent sits in the ranolazine SR protection space

US 6,479,496 occupies a formulation-and-PK intersection:

• Formulation: very high ranolazine weight fraction in an SR tablet.
• Clinical exposure: specific trough threshold (850 ng base/mL) maintained for 24 hours.
• Regimen: bounded by tablet number and dosing frequency.

This means the patent is most likely to be asserted against competitors offering SR ranolazine tablets with:

• similar high drug loading,
• similar trough maintenance,
• similar dosing cadence (once/twice),
• and a tablet dosing scheme of no more than two tablets per dose.

Where it is less likely to bite

It is less likely to cover:

• regimens that require more than two tablets per dose,
• products with ranolazine weight fraction below 50% (if formulation proof supports it),
• products that do not maintain the specified trough for 24 hours,
• products outside the specified dosing cadence.

Key Takeaways

• US 6,479,496 is a method-of-treatment patent targeting variant and exercise-induced angina with an SR ranolazine regimen that maintains plasma ≥850 ng base/mL for at least 24 hours.
• The independent claim (Claim 1) enforces five converging requirements: SR dosage form, ≥50% wt ranolazine, ≤2 tablets per dose, frequency = once/twice/three times per 24h, and trough threshold maintained for 24h.
• Dependent claims narrow to PK ceiling (~4000 ng/mL max), specific wt% bands (50-95% or 70-80%), dose size (500-1500 mg), and PK smoothness (peak-to-trough <4:1, <3:1, or <2:1).
• From an FTO lens, infringement is determined by whether a competitor product and prescribed regimen satisfies the claim’s formulation composition + dosing structure + measured PK profile simultaneously; design-arounds that attack any single independent-claim element are the most direct paths.

FAQs

1) Is US 6,479,496 a product claim or a method claim?
It is a method for treating a human patient with variant and exercise-induced angina by administering a sustained-release ranolazine regimen meeting defined formulation and PK targets.

2) What is the minimum plasma level requirement?
Claim 1 requires maintaining ranolazine plasma levels at a minimum of 850 ng base/mL for at least 24 hours.

3) What restricts dosing format in Claim 1?
Claim 1 limits each dose to no more than two tablets and requires dosing frequency selected from once, twice, or three times over 24 hours.

4) What composition thresholds appear in the claims?
Claim 1 requires at least 50% by weight ranolazine. Dependent claims add ranges of 50%-95% and 70%-80%.

5) Which claims control PK smoothness?
Claims 7-9 set peak-to-trough ratios over 24 hours below 4:1, 3:1, or 2:1, respectively.

References (APA)

[1] United States Patent 6,479,496. Claims 1-10 (as provided by the user).