Details for Patent: 6,902,742

Summary for Patent: 6,902,742

Title:	Multiparticulate modified release composition
Abstract:	The invention relates to a multiparticulate modified release composition that in operation delivers an active ingredient in a pulsed or bimodal manner. The multiparticulate modified release composition comprises an immediate release component and a modified release component; the immediate release component comprising a first population of active ingredient containing particles and the modified release component comprising a second population of active ingredient containing particles coated with a controlled release coating; wherein the combination of the immediate release and modified release components in operation deliver the active ingredient in a pulsed or a bimodal manner. The invention also relates to a solid oral dosage form containing such a multiparticulate modified release composition. The plasma profile achieved by the multiparticulate modified release composition is advantageous in reducing patient tolerance to the active ingredient and in increasing patient compliance by reducing dosage frequency.
Inventor(s):	John G. Devane, Paul Stark, Niall M. M. Fanning, Gurvinder Singh Rekhi
Assignee:	Alkermes Pharma Ireland Ltd , DV Technology LLC , Recro Gainesville LLC
Application Number:	US10/331,754
Patent Litigation and PTAB cases:	See patent lawsuits and PTAB cases for patent 6,902,742
Patent Claim Types: see list of patent claims	Use; Composition; Formulation; Delivery; Dosage form;

United States Drug Patent 6,902,742: Claim Scope, Expiration, and Patent Landscape

US Patent No. 6,902,742 protects a multiparticulate oral dosage system designed to deliver opioid and, optionally, non-opioid active ingredients in sequential pulses. Its central architecture is an immediate-release or first-release population combined with one or more delayed or modified-release populations. The patent covers compositions, solid dosage forms, and methods for treating pain.

The patent’s commercial significance is concentrated in four elements: opioid-containing particles, a subsequent modified-release population, pulsatile in vivo delivery, and dosage-form embodiments such as capsules, mini-tablets, multilayer tablets, and fast-melt tablets. The patent term has expired under the ordinary US 20-year patent-term framework, so it is no longer a standalone US blocking right as of 2025.[1][2]

What does US Patent 6,902,742 protect?

The broadest composition claim, claim 1, requires all of the following:

Required element	Scope
Multiparticulate composition	The product must contain discrete particles or particle populations
First population	Contains an opioid active ingredient
Subsequent population	Contains an opioid or non-opioid active ingredient
Modified release	The subsequent population has a modified-release coating, matrix, or both
Pulsatile delivery	Oral administration produces sequential or pulse-like release of the active ingredients

The claim is broader than a conventional extended-release opioid claim because it does not require every population to be modified release. A first population may release rapidly, while a later population is delayed or sustained.

The claim also does not require hydrocodone. Hydrocodone is introduced in claim 13, which narrows claim 1 to compositions containing hydrocodone or a pharmaceutically acceptable salt, enantiomer, or mixture.

What does “pulsatile” mean under the claims?

“Pulsatile” refers to release in distinct temporal events rather than one continuous release phase. Claims 16 through 19 provide the most important context:

• substantially all of the first population may release before the subsequent population begins releasing;
• the first population may release within about two hours in aqueous dissolution testing;
• the overall in vivo profile may mimic two or more doses of an immediate-release product.

The patent therefore targets dosage forms that reproduce repeated dosing events from a single oral administration.

The phrase “pulsatile manner” is a functional limitation. In an infringement dispute, a patentee would likely need evidence that the accused product produces the claimed release pattern, not merely that it contains immediate-release and extended-release particles.

How are claims 1 through 19 structured?

Claims 1 through 19 define the composition architecture and release behavior.

Core composition claims

Claim 1 is the principal independent composition claim. Claims 2 through 19 narrow the composition in several directions:

• Claim 2 limits the system to one first population and one subsequent population.
• Claim 3 requires immediate-release first particles and modified-release subsequent particles.
• Claims 4 and 5 specify either a modified-release coating or a modified-release matrix.
• Claim 6 requires opioid-containing subsequent particles.
• Claims 7 and 8 permit additional active ingredients in either population.
• Claim 9 covers a substantially pure enantiomer or racemic and nonracemic mixtures.
• Claim 10 adds an enhancer.
• Claims 11 and 12 address equal or unequal active-ingredient quantities, with each population containing approximately 0.1 mg to 1 g.
• Claim 13 narrows the opioid to hydrocodone or an accepted salt, enantiomer, or mixture.
• Claim 14 requires different in vitro dissolution profiles.
• Claims 15 and 16 emphasize immediate release followed by modified release.
• Claims 17 and 18 require an in vivo profile that mimics repeated immediate-release dosing.
• Claim 19 requires substantially complete release of the first population within about two hours.

The strongest practical limitations are claims 3, 15, 16, 17, and 19. They provide a more concrete technical definition than claim 1’s general reference to pulsatile release.

What active ingredients are covered?

The first population must contain an opiate. The subsequent population may contain:

• the same opioid;
• a different opioid;
• a non-opioid analgesic; or
• another active ingredient used with the opioid.

The claims expressly allow combination therapy. The composition can therefore combine an opioid with acetaminophen, an NSAID, an adjuvant analgesic, or another active ingredient, provided the population and release requirements are met.

The claims are not limited to one opioid salt or stereoisomer. Claim 9 broadens the stereochemical coverage, while claim 13 specifically identifies hydrocodone.

What dosage forms are covered by claims 20 through 25?

Claim 20 is an independent dosage-form claim covering a solid oral dosage form containing the multiparticulate composition of claim 1.

Claim	Dosage-form limitation
20	Solid oral dosage form
21	Hard- or soft-gelatin capsule containing blended particle populations
22	Capsule containing mini-tablets
23	Multilayer tablet with separate compressed particle layers
24	Rapidly dissolving dosage form
25	Fast-melt tablet

These claims extend protection beyond the particle formulation itself. A product may potentially fall within claim 20 even if the final commercial presentation is a tablet rather than a capsule, assuming the incorporated particles satisfy claim 1.

The capsule claims are directed to physical blending of particle populations. The multilayer tablet claim is materially different because it requires separate compressed layers. A product using a homogeneous matrix without discrete first and subsequent populations would face a stronger noninfringement argument against these dosage-form claims.

What method-of-use protection does US 6,902,742 provide?

Claims 26 and 27 cover treating pain by administering a therapeutically effective amount of the claimed multiparticulate composition.

Claim 26 uses the broad composition of claim 1. Claim 27 narrows the method to the hydrocodone embodiment in claim 13.

The method claims require more than administration of an opioid. The administered product must satisfy the composition limitations, including the first opioid population, later modified-release population, and pulsatile delivery behavior. A conventional hydrocodone extended-release tablet would not automatically fall within these claims.

What do claims 28 through 31 protect?

Claims 28 through 31 cover a specific delayed-release coating technology:

• Claim 28 requires a pH-dependent polymer coating that releases an active-ingredient pulse after a time delay.
• Claim 29 identifies methacrylate copolymers.
• Claim 30 requires a mixture of methacrylate and ammonio methacrylate copolymers in a ratio that produces the delayed pulse.
• Claim 31 specifies a 1:1 ratio.

These claims create a narrower formulation subgenus within the broader pulsatile-release concept. They are potentially more technically defensible than the broad functional language of claim 1 if the patent specification supports the coating mechanism and ratio.

A product using a different delayed-release mechanism, such as an osmotic pump, erodible barrier, rupturable coating, or purely matrix-based system, may avoid claims 28 through 31 while still raising issues under claims 1, 3, 5, 15, or 16.

How broad is the patent’s practical scope?

The patent’s practical scope can be divided into three layers.

Broadest layer: claim 1

Claim 1 captures a two-stage or multi-stage multiparticulate oral system in which an opioid is delivered first and a later population delivers an opioid or non-opioid. The claim does not require a particular polymer, opioid, capsule, tablet, dose, or dissolution apparatus.

Its breadth creates potential validity pressure. Terms such as “pulsatile,” “subsequent population,” “modified release,” and “following oral delivery” may require interpretation against the specification and prosecution history.

Intermediate layer: claims 3, 15, 16, and 19

These claims are more commercially concrete. They focus on:

• immediate-release particles;
• modified-release particles;
• sequential release;
• release of the first population within about two hours.

A generic or branded product using immediate-release opioid beads combined with delayed-release opioid beads would be the clearest technical target.

Narrowest layer: claims 28 through 31

These claims require pH-dependent methacrylate technology and, for claim 31, a 1:1 polymer ratio. They may be easier to design around by changing the polymer system, ratio, coating structure, or release trigger.

When did US Patent 6,902,742 lose exclusivity?

US 6,902,742 issued on June 7, 2005. The applicable US patent term is generally 20 years from the earliest effective nonprovisional filing date for applications filed after June 8, 1995, subject to patent-term adjustment, terminal disclaimers, and continuity rules.[2]

The patent’s term therefore expired in the 2020-2022 period under the ordinary statutory framework. As of 2025, the patent should be treated as expired and unavailable as a current US enforcement right. The expiration analysis should be distinguished from regulatory exclusivity, which is a separate FDA-granted right.

Does the patent still create generic launch risk?

No current patent-term barrier arises from US 6,902,742 alone. A generic applicant would not need to make a Paragraph IV certification against an expired patent unless the patent remained listed in a relevant Orange Book record and the applicant’s filing strategy required addressing it. A Paragraph IV certification is directed to a listed patent alleged to be invalid, unenforceable, or not infringed.[3]

The commercial risk now lies in other patents, including:

• later formulation patents;
• product-specific controlled-release patents;
• abuse-deterrent patents;
• manufacturing-process patents;
• crystalline-form or salt patents;
• method-of-use patents;
• patents owned by licensees or successor companies.

What is the Orange Book status of US 6,902,742?

A patent number by itself does not establish Orange Book listing. The Orange Book lists patents associated with approved drug products and relies on NDA-holder submissions.[3]

US 6,902,742 should not be treated as an Orange Book barrier without a product-specific listing. The claims mention hydrocodone, but the patent is not limited to one approved hydrocodone product. A product-specific Orange Book assessment would require matching the patent against the relevant NDA, dosage form, active ingredient, and listing history.

FDA approval and patent validity are separate questions. FDA approval does not validate the patent, and patent expiration does not eliminate the need to satisfy FDA approval requirements.

Which products could fall within the claims?

The highest-risk product profile would have these characteristics:

1. A solid oral opioid dosage form.
2. Discrete beads, pellets, granules, or mini-tablets.
3. A first opioid population that releases promptly.
4. A second population containing an opioid or non-opioid.
5. A delayed-release coating or matrix.
6. A release pattern approximating repeated immediate-release dosing.
7. Hydrocodone in one or more populations.

The following products would be less likely to fall within the broadest claims:

• a single homogeneous extended-release matrix;
• a dosage form with no discrete particle populations;
• a formulation in which the first population is not opioid-containing;
• a product with continuous release and no identifiable pulses;
• a product using only one active-ingredient population;
• a product whose delayed release does not follow oral administration in the claimed manner.

What manufacturing and intellectual-property barriers remain?

The patent does not monopolize every method of manufacturing an extended-release opioid. It focuses on the architecture and release function of the final dosage form.

Potential manufacturing issues include:

• producing separate particle populations with reproducible drug loading;
• applying a uniform pH-dependent coating;
• preventing interpopulation mixing or dose segregation;
• compressing coated particles without damaging the release barrier;
• maintaining dissolution performance after encapsulation or tableting;
• controlling particle-size distribution and coating weight gain.

These process steps may be covered by separate patents even if US 6,902,742 has expired. Manufacturing know-how may also remain protected as trade secrets.

How strong is the patent estate?

As an active US patent, the estate has no remaining exclusionary value after expiration. As a technical disclosure, it remains relevant because it describes a commercially important design strategy for simulating repeated dosing through one oral administration.

Factor	Assessment
Claim breadth	Broad at claim 1 level
Technical specificity	Stronger in claims 28-31
Product coverage	Broad across capsules, tablets, multilayer tablets, and fast-melt forms
Opioid coverage	Broad, with specific hydrocodone limitation
Validity pressure	Potentially significant for functional terms and prior-art combinations
Current US enforceability	None after expiration
Design-around options	Available through nonmultiparticulate, non-pulsatile, or different coating systems
Regulatory relevance	Product-dependent; not established by the patent number alone
Biosimilar relevance	None; this is a small-molecule formulation patent

Does biosimilar risk apply?

No. Biosimilar pathways apply to biological products, not hydrocodone or other conventional small-molecule opioids.[4] The relevant competitive pathways are abbreviated new drug applications, 505(b)(2) applications, and, where applicable, full NDAs.

A follow-on product using the same active ingredient may face formulation, labeling, bioequivalence, abuse-deterrence, and manufacturing requirements, but it would not face biosimilar substitution rules.

What litigation and licensing issues affect the patent?

The supplied claims do not identify a specific NDA, licensee, settlement, Paragraph IV notice, or litigation docket. No product-specific litigation conclusion can be drawn from the claims alone.

For commercial diligence, the decisive records are:

• USPTO Patent Center continuity and maintenance records;
• the patent’s assignment history;
• Orange Book patent listings for the relevant NDA;
• federal district-court and Federal Circuit dockets;
• ANDA litigation records under the Hatch-Waxman framework;
• any license, royalty, or settlement agreement tied to a product or patent family.

Because the patent has expired, any historical litigation would matter primarily for understanding claim construction, validity, licensing scope, or successor patent families.

Key Takeaways

• US 6,902,742 covers multiparticulate pulsatile oral delivery, centered on a first opioid population and a later modified-release population.
• Claim 1 is broad and functionally defined.
• Claims 3, 15, 16, and 19 provide the clearest commercial formulation boundaries.
• Claims 28 through 31 target pH-dependent methacrylate and ammonio methacrylate coating systems, including a 1:1 ratio.
• Hydrocodone is a specific but nonexclusive embodiment under claim 13.
• Claims 20 through 25 extend coverage to capsules, mini-tablets, multilayer tablets, rapidly dissolving forms, and fast-melt tablets.
• Claims 26 and 27 cover pain-treatment methods using the claimed compositions.
• The patent’s US term expired in the 2020-2022 period under the ordinary patent-term framework.
• It should not be treated as a current US blocking patent in 2025.
• No biosimilar issue applies.
• Current generic-launch risk depends on later, product-specific patents and regulatory requirements rather than this expired patent alone.
• Orange Book status cannot be inferred solely from the patent number or hydrocodone language.

FAQs

Can an extended-release hydrocodone tablet infringe US 6,902,742?

Only if it contains the required first and subsequent active-ingredient populations and produces the claimed pulsatile release profile. A single continuous extended-release matrix would generally present a weaker infringement case.

Does the patent cover abuse-deterrent opioid formulations?

Not expressly. The claims focus on multiparticulate release timing, not physical, chemical, or opioid-antagonist abuse-deterrence mechanisms. An abuse-deterrent product could implicate the patent only if it independently satisfies the population and pulsatile-release limitations.

Can a product avoid claims 28 through 31 by changing the polymer ratio?

Potentially. Changing the polymer system or ratio may avoid the narrower coating claims, but it would not automatically avoid the broader composition claims if the product still contains the claimed populations and produces pulsatile delivery.

Is US 6,902,742 relevant to a 505(b)(2) application?

It may be relevant historically or technically, but an expired patent generally does not create a current patent-exclusivity obstacle. A 505(b)(2) applicant must still address FDA requirements, product differences, clinical bridging, labeling, and any unexpired patents.

Does patent expiration eliminate all regulatory barriers to a generic opioid?

No. Expiration removes this patent’s exclusionary term but does not remove requirements involving abuse-deterrent labeling, controlled-substance regulation, bioequivalence, manufacturing controls, risk-management obligations, or other unexpired patents.

References

1. United States Patent and Trademark Office. (2005). US Patent No. 6,902,742. https://patents.google.com/patent/US6902742
2. 35 U.S.C. §§ 154, 156, and 253. Patent term and patent-term adjustment provisions.
3. U.S. Food and Drug Administration. (2024). Approved drug products with therapeutic equivalence evaluations: Orange Book. https://www.fda.gov/drugs/drug-approvals-and-databases/approved-drug-products-therapeutic-equivalence-evaluations-orange-book
4. U.S. Food and Drug Administration. (2024). Biosimilar and interchangeable biosimilar products. https://www.fda.gov/drugs/biosimilars/biosimilar-and-interchangeable-biosimilar-products

Drugs Protected by US Patent 6,902,742

Applicant	Tradename	Generic Name	Dosage	NDA	Approval Date	TE	Type	RLD	RS	Patent No.	Patent Expiration	Product	Substance	Delist Req.	Patented / Exclusive Use	Submissiondate

International Family Members for US Patent 6,902,742

Country	Patent Number	Estimated Expiration	Supplementary Protection Certificate	SPC Country	SPC Expiration
Argentina	021858
Austria	411011
Australia	1335000
Australia	2004202078
Australia	2005247019
Australia	2006285349
Australia	2006343445