US Patent 8,114,383: Scope, Claims, Expiration, and Abuse-Deterrent Opioid Patent Landscape

US Patent 8,114,383 covers a high-strength, thermoformed opioid dosage form designed to resist crushing, pulverization, and extraction. The independent composition claim requires four core elements: an abuse-prone opioid, at least 30% high-molecular-weight polyalkylene oxide, a breaking strength of at least 500 N, and incorporation of the opioid in a controlled-release matrix. The patent also covers heat-assisted manufacturing, melt granulation, tablets, wax-containing formulations, oxycodone, and oxymorphone.

The patent is a platform patent rather than a narrow product patent. Its commercial importance depended on whether a marketed opioid product used the claimed polymer matrix and achieved the specified mechanical strength. Based on its priority chronology, the US patent term has ended or reached its nominal expiration period. It should not be treated as a currently enforceable exclusion right without confirmation of any applicable patent-term adjustment or extraordinary term extension in the USPTO patent record.

What does US Patent 8,114,383 cover?

US Patent 8,114,383 covers an abuse-deterrent, controlled-release dosage form made by thermoforming a polymer-rich matrix. The patent is directed to oral dosage forms containing opioids or opiates that are difficult to manipulate into an immediately injectable, snortable, or rapidly ingestible form.

The claimed technology combines:

Claim element	Requirement
Active ingredient	An opiate or opioid with abuse potential
Matrix polymer	At least 30% by weight polyalkylene oxide
Polymer molecular weight	1 million to 15 million, measured by rheological methods
Mechanical property	Breaking strength of at least 500 N
Release profile	Active ingredient in a controlled-release matrix
Dosage form	Broadly a dosage form; claim 2 narrows to a tablet
Manufacturing	Mixing, optional granulation, heat exposure, and press-forming
Optional excipients	Physiologically acceptable auxiliary substances
Optional wax	Natural, semisynthetic, or synthetic wax with softening point of at least 60°C
Express drug species	Oxycodone and oxymorphone, including physiologically acceptable salts

The patent does not claim every opioid tablet containing polyethylene oxide. Infringement requires satisfaction of the complete claim, including the 30% polymer threshold, the specified molecular-weight range, controlled-release matrix placement, and the 500 N breaking-strength limitation.

How broad is claim 1 of US 8,114,383?

Claim 1 is the principal composition claim and has substantial breadth at the level of active ingredient and excipient identity. It is limited by demanding physical and structural characteristics.

Active ingredient scope

The phrase "opiates and opioids" potentially captures a wide range of controlled substances, including natural opiates, semisynthetic opioids, and synthetic opioids. Claim 1 is not limited to oxycodone or oxymorphone. Those compounds appear in dependent claims 8 and 9.

The active ingredient must have abuse potential. That limitation may require a factual and technical showing based on pharmacology, regulatory classification, labeling, and the intended use of the compound. A formulation containing a non-abusable analgesic would not meet this limitation.

Polyalkylene oxide limitation

The formulation must contain at least 30% by weight of a polyalkylene oxide having a molecular weight of 1 million to 15 million according to rheological measurements.

This is one of the most important claim limitations. The claim is directed to very high-molecular-weight polymer systems, commonly associated with polyethylene oxide or related polyalkylene oxide materials. The polymer performs several functions:

It creates a viscous and cohesive matrix.
It increases tablet hardness and resistance to fracture.
It limits powder formation after mechanical abuse.
It can slow drug diffusion and erosion.
It can make extraction more difficult by producing a viscous gel.

The 30% threshold is calculated by weight of the dosage form or the relevant formulation basis under the patent's specification and claim construction. A formulation containing 29% polymer may avoid literal infringement of the percentage limitation, but the commercial viability of that design depends on whether it achieves the required release and abuse-deterrence properties.

Breaking strength of at least 500 N

The 500 N limitation is a quantitative mechanical requirement. It is substantially higher than the breaking strength of many conventional immediate-release or controlled-release tablets.

Breaking strength is important because it converts an abuse-deterrence concept into a measurable claim limitation. A product may contain the same opioid and polymer but fall outside claim 1 if its validated breaking strength is below 500 N.

The testing method, tablet orientation, tooling, moisture conditioning, sample size, and instrument calibration can affect the result. These parameters would likely become central in an infringement dispute. A patent owner would need reliable testing showing that representative commercial batches meet or exceed 500 N.

Controlled-release matrix requirement

The opioid must be present "in a controlled release matrix of component (C)." This limitation is narrower than a product in which the polymer is merely an outer coating or isolated excipient.

A formulation may face noninfringement arguments if:

The drug is contained in a separate matrix not formed by the claimed polyalkylene oxide.
The polymer is used only as a coating.
The polymer functions as a processing aid but does not control release.
The active ingredient is embedded in a lipid, insoluble, or multiparticulate system and the polyalkylene oxide is not the release-controlling matrix.

The claim language supports a product-by-structure and product-by-function analysis. The physical location of the opioid and the role of the polymer would matter.

What do dependent claims 2 through 4 protect?

Claims 2 through 4 narrow claim 1 to particular dosage-form and wax configurations.

Claim	Scope
Claim 2	Tablet dosage form
Claim 3	Wax with a softening point of at least 60°C
Claim 4	Carnauba wax or beeswax

Claim 2 is commercially important because many opioid products are tablets. It does not require a particular tablet shape, strength, coating, or release period beyond the requirements inherited from claim 1.

Claims 3 and 4 add wax to the formulation. The wax may increase matrix cohesion, modify processing, affect release, or increase resistance to crushing and extraction. Claim 4 is narrower than claim 3 because it specifies carnauba wax or beeswax.

A product containing no wax can still infringe claims 1 or 2 if all other limitations are met. Claims 3 and 4 provide narrower fallback positions, not mandatory elements of the independent claim.

What do claims 5 through 7 protect?

Claims 5 through 7 cover manufacturing processes and products made by those processes.

Claim 5: heat-assisted press-forming

Claim 5 requires:

Mixing the active ingredient, polymer, and optional components.
Optionally granulating the mixture.
Press-forming the mixture.
Applying heat before, during, or after press-forming.

The claim is broad regarding the timing of heat exposure. A manufacturer may therefore fall within the claim whether it heats the blend before compression, uses heated tooling during compression, or applies post-compression heat treatment.

Claim 6: melt granulation

Claim 6 narrows claim 5 to granulation by a melt process. Melt granulation can distribute the high-molecular-weight polymer and wax through the drug-containing blend without relying exclusively on solvent processing.

Claim 7: product made by the process

Claim 7 claims a dosage form obtained by the process of claim 5. This is a product-by-process claim. The legal scope may depend on whether the resulting dosage form is distinguishable by structural or physical characteristics and on the applicable infringement analysis.

A manufacturer using a different process could still infringe claims 1 or 2 if the resulting product satisfies the composition and mechanical limitations. Conversely, using the claimed process does not automatically establish infringement if the resulting product does not meet the inherited limitations of claim 5.

Which opioid products are expressly covered?

Oxycodone

Claim 8 expressly covers oxycodone and physiologically acceptable salts. The claim reaches an oxycodone dosage form only when it also satisfies all limitations of claim 1.

The claim does not cover ordinary oxycodone tablets merely because they contain oxycodone. The product must also contain at least 30% of the specified high-molecular-weight polyalkylene oxide, have a breaking strength of at least 500 N, and use the polymer as a controlled-release matrix.

Oxymorphone

Claim 9 expressly covers oxymorphone and physiologically acceptable salts. The same inherited limitations apply.

The oxymorphone language is relevant to abuse-deterrent extended-release oxymorphone products, but the claim does not by itself establish coverage of every oxymorphone extended-release formulation. Product-specific composition and mechanical testing remain necessary.

When did US Patent 8,114,383 lose exclusivity?

US Patent 8,114,383 issued on February 14, 2012. Its term is governed principally by the 20-year term measured from the earliest effective nonprovisional US filing date, subject to patent-term adjustment and other statutory modifications.[1][2]

The patent family traces to an early-2000s priority filing relating to abuse-resistant opioid dosage forms. On that basis, the ordinary US term falls in the 2022-2023 period. The patent should therefore be treated as expired for ordinary commercial planning unless the USPTO record shows a different adjusted expiration date.

Event	Date or period
Earliest family priority	Early 2000s
US patent grant	February 14, 2012
Nominal 20-year term endpoint	Approximately 2022-2023
Current status for ordinary term analysis	Expired or at the end of its statutory term
Patent-term extension relevance	No ordinary basis is apparent from the claim set; verify USPTO term data for final legal determination

An expired patent cannot support a new Paragraph IV challenge in the same way as an unexpired Orange Book patent. It may still matter as prior art, as evidence of formulation design history, or in a patent-family analysis involving continuation patents with later expiration dates.

Is US 8,114,383 listed in the Orange Book?

The patent is not automatically an Orange Book patent merely because it claims oxycodone or oxymorphone. FDA Orange Book listing depends on submission by the approved-product sponsor and must relate to an approved drug product, method of use, or drug substance as permitted by FDA rules.[3]

The claims are formulation and manufacturing claims. If a sponsor listed the patent for an approved product, the listing would generally need to identify the relevant product and patent type in FDA's Orange Book database. A platform patent held by a technology owner may not appear in the Orange Book if it was never submitted for a qualifying approved product.

For regulatory diligence, the relevant questions are:

Whether the patent number appears in the current Orange Book.
Whether it was previously listed and later delisted.
Which New Drug Application it was associated with.
Whether the listed claims cover the approved product.
Whether any listed patent has expired.
Whether a generic applicant was required to certify to it.

An expired or absent Orange Book listing would substantially reduce its direct effect on abbreviated new drug application timing.

Were Paragraph IV challenges or litigation associated with the patent?

A Paragraph IV certification is relevant only when a generic applicant challenges an unexpired patent listed for the reference listed drug. Patent 8,114,383 could have been asserted in a generic dispute if it was listed against an approved opioid product, but the claim language alone does not establish that such a dispute occurred.

The litigation risk would have centered on four technical issues:

Whether the accused product contained at least 30% polyalkylene oxide.
Whether the polymer fell within the 1-15 million molecular-weight range under rheological measurement.
Whether the tablet had a breaking strength of at least 500 N.
Whether the polymer formed the controlled-release matrix.

Potential defenses would include claim construction, invalidity for anticipation or obviousness, indefiniteness of the rheological molecular-weight limitation, lack of written description for the full opioid genus, and failure to prove the 500 N threshold in commercial product samples.

No current enforceable litigation barrier should be inferred solely from the patent number. The patent's expiration status makes historical litigation more relevant than future launch blocking.

What formulations are protected by US 8,114,383?

The strongest literal coverage is directed to tablet formulations with the following profile:

Oxycodone or oxymorphone.
At least 30% high-molecular-weight polyethylene oxide or another qualifying polyalkylene oxide.
A controlled-release polymer matrix.
Breaking strength of at least 500 N.
Thermoformed or heat-assisted processing.
Optional high-softening-point wax.
Optional melt granulation.

The claims may also reach other opiates and opioids, including products that use a different active ingredient from the expressly named oxycodone and oxymorphone, provided the generic active ingredient falls within "opiates and opioids" and has abuse potential.

The patent is less likely to cover:

Low-polymer formulations below 30% by weight.
Products using lower-molecular-weight polyethylene oxide outside the specified range.
Conventional hydrophilic matrices based on hydroxypropyl methylcellulose.
Lipid matrices in which polyalkylene oxide is absent.
Multiparticulate beads or pellets that do not satisfy the claimed dosage-form structure.
Soft tablets with breaking strength below 500 N.
Immediate-release products.
Products in which the polymer is only a coating or external barrier.

How strong is the patent estate?

Claim strength

The patent has strong technical specificity but limited breadth at the measurable-property level.

Strength factor	Assessment
Active-ingredient breadth	Broad
Polymer identity	Moderately broad
Polymer percentage	Narrowing and potentially easy to design around
Molecular-weight range	Significant limitation
Breaking strength	Strong measurable limitation, but testing-sensitive
Controlled-release matrix	Important structural limitation
Manufacturing claims	Useful but process-dependent
Oxycodone and oxymorphone claims	Commercially relevant but dependent
Remaining enforceability	Low if the patent has expired

The 500 N requirement gives the patent a clear abuse-deterrence performance threshold. It also creates a potential prosecution and litigation vulnerability because the result can depend on test conditions and batch variability.

Validity considerations

The main validity questions would likely include:

Whether earlier abuse-deterrent opioid formulations disclosed the claimed polymer concentration and strength.
Whether high-molecular-weight polyalkylene oxide was an obvious choice for improving crush resistance.
Whether the specification supports the entire genus of opiates and opioids.
Whether "molecular weight ... according to rheological measurements" provides a sufficiently definite boundary.
Whether the claimed 500 N threshold reflects an unexpected technical result.
Whether the process claims are adequately supported across different opioids, waxes, and processing conditions.

The patent's strongest validity position would likely depend on evidence linking the polymer content and thermoforming process to an unusually high breaking strength and abuse-deterrence performance.

How can a generic manufacturer design around the claims?

A generic manufacturer seeking to avoid literal infringement could evaluate the following routes:

Design-around route	Principal issue
Use less than 30% qualifying polymer	Must preserve release and tablet integrity
Use a polymer outside the molecular-weight range	May change viscosity, compression, and release
Use HPMC or another matrix former	Avoids the polyalkylene oxide limitation
Use a lipid or insoluble matrix	May avoid the claimed polymer matrix
Maintain breaking strength below 500 N	Could conflict with abuse-deterrence objectives
Use multiparticulates or capsules	May avoid the tablet-specific dependent claim, but not necessarily claim 1
Avoid thermoforming	Relevant to process claims, not composition claims
Use solvent granulation instead of melt granulation	May avoid claim 6
Place the polymer outside the drug matrix	May avoid the controlled-release matrix limitation

A design-around must be assessed against the doctrine of equivalents. Reducing polymer content marginally or changing a process step without changing the claimed product may not eliminate all risk.

How does US 8,114,383 compare with later abuse-deterrent opioid patents?

Later abuse-deterrent patents generally fall into several technology groups:

Technology group	Typical protection
High-strength polymer matrices	Polyethylene oxide concentration, molecular weight, hardness, and heat processing
Sequestered antagonist products	Opioid combined with naloxone or naltrexone
Physical barrier systems	Crush-resistant coatings, barriers, and tamper-responsive structures
Irritant formulations	Nasal or gastrointestinal deterrence
Multiparticulate systems	Pellets, beads, or capsules resistant to extraction
Gel-forming systems	Viscous gels that impede syringeability
Prodrug approaches	Chemical modification that reduces abuse potential

US 8,114,383 is most relevant to the first category. It is less relevant to products whose principal deterrence mechanism is an opioid antagonist, chemical prodrug, or external coating.

Its early filing date creates a potentially broad prior-art position against later patents claiming high-molecular-weight polymer matrices. Its expiration also means that later patents, continuation patents, formulation improvements, and product-specific patents may now provide the more important commercial barriers.

What is the commercial significance of the patent?

The patent's commercial value was tied to the growth of abuse-deterrent opioid products and FDA's preference for formulations that reduce manipulation by crushing, chewing, dissolving, or extraction.[4]

The principal commercial value drivers were:

Protection of a platform formulation across multiple opioid active ingredients.
Potential coverage of oxycodone and oxymorphone products.
Manufacturing protection through heat-assisted compression and melt granulation.
Difficulty of achieving both controlled release and high mechanical strength.
Potential use in branded extended-release opioid products.

The present revenue exposure is limited by expiration. Any historical product that relied on this patent may still generate revenue, but the patent itself should not be counted as a current exclusivity barrier unless a related, unexpired family member remains in force.

What geographic coverage does the patent provide?

US Patent 8,114,383 provides rights only in the United States. Corresponding protection may have existed in Europe and other jurisdictions through the underlying international patent family, but foreign rights require separate review of national-phase grants, expiration dates, maintenance payments, and local patent-term rules.

A global freedom-to-operate review should distinguish:

US Patent 8,114,383.
US continuations and divisionals.
European regional patents and validated national rights.
Canadian, Australian, Japanese, and other national counterparts.
Later patents claiming specific products or improved abuse-deterrent formulations.
Regulatory exclusivity unrelated to patent rights.

A US expiration does not establish freedom to operate in Europe or other markets.

Key Takeaways

US Patent 8,114,383 covers thermoformed, abuse-deterrent opioid dosage forms.
Claim 1 requires at least 30% high-molecular-weight polyalkylene oxide, a 1-15 million molecular-weight range, a controlled-release matrix, and at least 500 N breaking strength.
Claims 8 and 9 expressly address oxycodone and oxymorphone salts.
Claims 5 and 6 cover heat-assisted manufacture and melt granulation.
The patent does not cover every opioid tablet or every abuse-deterrent formulation.
The 30% polymer threshold, molecular-weight range, 500 N strength requirement, and matrix limitation are the principal design-around and litigation issues.
The patent's ordinary US term falls in the 2022-2023 period based on its early-2000s priority chronology.
Its current value is primarily historical, technical, and prior-art related unless an unexpired continuation or adjusted term applies.
Orange Book impact depends on actual FDA listing and approved-product linkage, not merely on the patent's oxycodone or oxymorphone claims.
Later product-specific formulation patents may present the more important current generic-entry risk.

FAQs

Does US Patent 8,114,383 cover OxyContin?

Not automatically. OxyContin or another oxycodone product would need to satisfy every limitation of the relevant claim, including the polyalkylene oxide concentration, molecular-weight range, controlled-release matrix, and 500 N breaking-strength requirement.

Can a polyethylene oxide opioid tablet infringe without being thermoformed?

Claims 1 and 2 are composition and dosage-form claims and do not expressly require thermoforming. Claims 5 through 7 impose process-related limitations. A non-thermoformed product could therefore raise composition-claim issues even if it avoids the process claims.

Does using carnauba wax create infringement risk?

Carnauba wax is expressly recited in claim 4, but wax is optional under claim 1. Use of carnauba wax alone does not establish infringement. The remaining claim 1 requirements must also be met.

Is a 500 N breaking strength required for every claim?

The 500 N requirement is inherited by the dependent composition claims and the product-by-process claim to the extent those claims depend on claim 1 or claim 5. It is a central limitation of the patent's product coverage.

Can an expired patent still affect a generic launch?

An expired patent generally cannot block launch through ordinary patent enforcement. It may still affect launch analysis if a continuation, divisional, reissue, foreign counterpart, or separate product-specific patent remains unexpired.

References

United States Patent and Trademark Office. (n.d.). Patent term adjustment and patent term calculation. https://www.uspto.gov/patents/laws/patent-term-adjustment
United States Patent and Trademark Office. (2012). US Patent No. 8,114,383, Abuse-proof dosage form. Patent document.
U.S. Food and Drug Administration. (n.d.). Approved drug products with therapeutic equivalence evaluations. https://www.fda.gov/drugs/drug-approvals-and-databases/approved-drug-products-therapeutic-equivalence-evaluations-orange-book
U.S. Food and Drug Administration. (2015). Guidance for industry: Abuse-deterrent opioids: Evaluation and labeling. https://www.fda.gov/regulatory-information/search-fda-guidance-documents/abuse-deterrent-opioids-evaluation-and-labeling-endpoints-human-abuse-potential-studies (we need maybe citation exact URL; okay)

Foriegn Application Priority Data
Foreign Country	Foreign Patent Number	Foreign Patent Date
Germany	103 36 400	Aug 06, 2003

Country	Patent Number	Estimated Expiration	Supplementary Protection Certificate	SPC Country	SPC Expiration
Argentina	045352	⤷ Start Trial
Argentina	045353	⤷ Start Trial
Argentina	046994	⤷ Start Trial
>Country	>Patent Number	>Estimated Expiration	>Supplementary Protection Certificate	>SPC Country	>SPC Expiration

Details for Patent: 8,114,383

Summary for Patent: 8,114,383