Details for Patent: 9,737,530

Which drugs does patent 9,737,530 protect, and when does it expire?

Patent 9,737,530 protects XTAMPZA ER and is included in one NDA.

This patent has one patent family member in one country.

Summary for Patent: 9,737,530

Title:	Process of making stable abuse-deterrent oral formulations
Abstract:	The present disclosure relates to cured pharmaceutical compositions designed to reduce the potential for improper administration of drugs that are subject to abuse, the process of curing such composition in order to improve the dissolution stability, method of using the same for treatment of pain.
Inventor(s):	Said Saim, Alison B. Fleming, Ravi K. Varanasi
Assignee:	Collegium Pharmaceutical Inc
Application Number:	US15/255,859
Patent Litigation and PTAB cases:	See patent lawsuits and PTAB cases for patent 9,737,530
Patent Claim Types: see list of patent claims	Use; Composition; Dosage form;

US Patent 9,737,530: Scope, Claim Construction, Expiration Risk, and Patent Landscape

US Patent 9,737,530 protects a lipid-based microparticle manufacturing process that combines a drug, wax, and fatty acid in a substantially homogeneous melt, converts the melt into solid microparticles, and cures the particles for at least about 48 hours at controlled temperatures. The claims specifically cover oxycodone microparticles using myristic acid or stearic acid, dissolution-stability performance after accelerated storage, pharmaceutical compositions, capsules, and pain-treatment methods.

The patent is technically narrow in its required combination of melt processing, microparticle formation, curing, and lipid excipients. Its commercial relevance is higher for extended-release or abuse-deterrent opioid formulations than for ordinary immediate-release oxycodone products.

What does US Patent 9,737,530 protect?

The patent has four principal claim groups:

Claim group	Claims	Protected subject matter
Manufacturing process	1-9	Melt preparation, microparticle formation, optional formulation, and curing
Pharmaceutical compositions and capsules	10-15	Products prepared by the claimed process and cured microparticle compositions
Pain-treatment methods	16-19	Administration of the claimed oxycodone compositions or microparticles
Performance limitations	2-6	Dissolution stability after six months at 25°C and 60% relative humidity

The independent claims are claims 1, 10, 14, 16, 17, 18, and 19. Claim 1 is the principal process claim. Claim 14 is the principal composition claim. Claims 16 through 19 are method-of-treatment claims.

What is the core process limitation?

Claim 1 requires all of the following:

1. A mixture containing either:
   • one or more drugs, pharmaceutically acceptable waxes, and pharmaceutically acceptable fatty acids; or
   • one or more drugs in fatty-acid-salt form and one or more pharmaceutically acceptable waxes.
2. Heating to form a substantially homogeneous melt.
3. Formation of solid microparticles from that melt.
4. Optional further formulation with excipients.
5. Curing at 25°C through the inversion temperature for at least approximately 48 hours.

A formulation that uses the same ingredients but is made by conventional granulation, spray drying, solvent evaporation, or compression may not satisfy the process claim unless the accused product was actually prepared through the claimed melt and curing sequence.

How should the key claim terms be interpreted?

“Substantially homogeneous melt”

This term requires more than merely mixing solid excipients. The process must produce a melt with sufficient uniformity for the drug, wax, and fatty-acid components to form the claimed microparticle structure. In litigation, evidence would likely include:

• Heating profile;
• Melt viscosity;
• Microscopic or spectroscopic evidence of phase uniformity;
• Drug and excipient distribution;
• Batch manufacturing records;
• Process-development reports.

The term is not limited to a single wax, a single fatty acid, or a single drug. Claim 1 uses “one or more,” creating broad compositional coverage.

“Solid microparticles”

The claims require discrete solid particles rather than a bulk lipid matrix alone. Particle-size data, morphology, residual solvent data, and release testing would be relevant to infringement analysis.

The claims supplied do not define a specific particle-size range. That omission broadens the structural scope but may create disputes over the boundary between microparticles, granules, pellets, and conventional solid dosage forms.

“Curing”

Curing is a central limitation. It requires maintaining the microparticles or formulated microparticles at a temperature within the range of 25°C up to and including the inversion temperature for at least approximately 48 hours.

The curing requirement distinguishes the patent from a process that merely cools a melt and fills capsules. A short post-manufacturing hold, ambient storage, or routine warehouse exposure could raise factual issues, but passive storage would not automatically establish intentional curing.

“Inversion temperature”

The patent identifies approximately 36°C for the oxycodone-myristic-acid embodiment and approximately 53°C for the oxycodone-stearic-acid embodiment.

The inversion temperature appears to define a phase or structural transition relevant to the lipid matrix. Claims 7 and 8 use these values for specific oxycodone embodiments. Claim 9 adds a two-stage curing sequence:

1. A first temperature above the inversion temperature; and
2. A second temperature below the inversion temperature.

That limitation may cover a controlled thermal-conditioning cycle rather than a single constant-temperature cure.

Which claims are strongest for oxycodone products?

Claims 7, 8, 12, 13, 15, 19, and related process claims are the most commercially relevant to oxycodone.

Claim	Oxycodone limitation	Commercial significance
7	Oxycodone, myristic acid, inversion temperature of about 36°C	Specific oxycodone-myristic-acid process
8	Oxycodone, stearic acid, inversion temperature of about 53°C	Specific oxycodone-stearic-acid process
12	Composition prepared under claim 7	Product-by-process protection
13	Capsule containing claim 12 composition	Finished dosage form
15	Cured oxycodone-myristic-acid microparticles	Composition claim
19	Pain treatment using claim 15 particles	Method-of-treatment claim

The myristic-acid embodiment has the clearest claim-chain concentration because it appears in claims 7, 12, 13, 15, and 19. The stearic-acid embodiment appears primarily in claim 8 and does not receive the same downstream claim layering in the supplied claims.

What dissolution performance does the patent require?

Claims 2 through 6 impose post-storage dissolution limitations. The testing conditions include:

• Six months at 25°C and 60% relative humidity;
• USP Apparatus I;
• 100 rpm where specified;
• 900 mL of pH 4.5 sodium acetate buffer;
• 0.03% Tween 20;
• 37°C;
• Assessment at the four-hour dissolution point.

The claimed changes are progressively narrower:

Claim	Dissolution limitation
2	Less change than otherwise identical uncured microparticles
3	Less than 15% change in mean drug released at four hours
4	Less than 10% change
5	Less than 5% change
6	Less than 2.5% change

These limitations may provide useful validity and infringement leverage because they connect the process to a measurable technical result. They also create proof burdens. An accused party would likely challenge:

• Whether the comparator is truly “otherwise identical”;
• Whether the storage and dissolution protocols were followed exactly;
• Whether the result is statistically reproducible;
• Whether “change” means absolute percentage-point change or relative percentage change;
• Whether the claimed performance is inherent in every product made by the process.

Claims 3 through 6 are narrower than claim 1 and may be more vulnerable to non-infringement if a competing product uses a different dissolution profile or fails to meet the specified stability result.

How broad is the composition claim in claim 14?

Claim 14 covers pharmaceutically acceptable solid microparticles or formulated microparticles comprising:

• A mixture prepared from a melt;
• One or more pharmaceutically acceptable waxes;
• One or more drugs or fatty-acid salts of drugs;
• A sufficient amount of fatty acid to provide a substantially homogeneous form; and
• Curing at 25°C through the inversion temperature for at least approximately 48 hours.

Unlike claim 1, claim 14 is directed to the resulting material rather than solely to the manufacturing steps. This is important because a composition claim may be asserted against a product even when the patentee cannot prove every detail of the competitor’s manufacturing process.

The composition claim remains limited by the melt-derived structure and curing history. A generic manufacturer could attempt to design around it by using:

• A non-lipid polymer matrix;
• A wax without the claimed fatty-acid component;
• A fatty-acid-free formulation;
• Solvent-based particle formation;
• Spray drying that does not produce the claimed melt;
• A different solid-state structure;
• A manufacturing process that does not include the claimed curing period.

Whether such alternatives avoid infringement would depend on the product’s actual composition and process history.

Does the patent protect oxycodone itself?

No. The patent does not claim oxycodone as a molecule, oxycodone hydrochloride as a known active ingredient, or pain treatment with any oxycodone product generally.

Its protection is directed to a particular delivery platform:

• Oxycodone;
• Wax and fatty-acid excipients;
• Melt-generated microparticles;
• Thermal curing;
• Stability-controlled dissolution.

An ordinary oxycodone tablet, capsule, solution, or conventional extended-release formulation would not fall within the patent merely because it contains oxycodone.

What patents protect competing oxycodone products?

US Patent 9,737,530 should be analyzed against several separate patent categories:

Patent category	Typical protected subject matter	Relevance to US 9,737,530
Active-ingredient patents	Oxycodone or oxycodone salts	Usually expired or historical for established oxycodone products
Release-profile patents	Extended-release oxycodone dosing and release kinetics	Potentially overlapping therapeutic and formulation rights
Abuse-deterrent patents	Hardness, gelling, extraction resistance, tamper resistance	May overlap commercially but not necessarily technically
Microparticle patents	Lipid, polymer, or multiparticulate delivery systems	Closest technical prior-art and freedom-to-operate category
Manufacturing patents	Melt extrusion, spray congealing, curing, coating, encapsulation	Relevant to process infringement
Method-of-use patents	Pain, opioid substitution, dosing schedules, abuse-deterrent use	Relevant to ANDA certification and product labeling
Regulatory exclusivity	New chemical entity, new clinical investigation, orphan exclusivity	Separate from patent rights

The supplied claims do not establish that any marketed oxycodone product practices the patent. Patent practice must be confirmed through product composition, regulatory filings, manufacturing disclosures, or litigation evidence.

When does US Patent 9,737,530 lose exclusivity?

The patent issued on August 22, 2017. A US utility patent generally expires 20 years from the earliest effective nonprovisional filing date, subject to patent-term adjustment, patent-term extension, terminal disclaimers, and other statutory adjustments.[1]

The grant date alone does not establish the expiration date. The controlling date must be taken from the USPTO Patent Center record and the patent’s term-adjustment information. The patent may also have continuation, divisional, or related-family rights with different expiration dates.

A commercial freedom-to-operate analysis should therefore distinguish:

Event	Legal effect
Patent issuance	Creates enforceable patent rights, subject to validity and enforceability
Patent expiration	Ends ordinary patent enforcement rights
FDA regulatory exclusivity expiration	Ends a separate FDA barrier but does not invalidate patents
Orange Book delisting	Removes a listed patent from certain FDA certification procedures but does not necessarily extinguish patent rights
Patent disclaimer or terminal disclaimer	Can shorten the enforceable term
Patent-term adjustment	Can extend the ordinary 20-year term

What is the Orange Book status of US Patent 9,737,530?

The patent number alone does not establish Orange Book listing status.

The claims are drafted as process, composition, capsule, and method-of-treatment claims. Orange Book listing is generally associated with patents claiming an approved drug substance, drug product, or method of use, subject to FDA listing rules. A process patent is ordinarily not listed as an approved drug-product patent merely because it covers a pharmaceutical manufacturing method.[2]

The most plausible listing relevance would arise from:

• A claim directed to the approved dosage form;
• A claim directed to the drug product composition;
• A claim directed to an approved method of use;
• A sponsor submission identifying the patent for FDA publication.

Claims 10 through 15 could be evaluated for drug-product listing, but the patent’s broad dependence on a specific cured microparticle process may make listing and enforcement more fact-dependent than a conventional formulation patent.

Could a generic applicant file a Paragraph IV challenge?

Yes. If the patent is listed in the Orange Book for a relevant reference-listed drug, an ANDA applicant could certify under Paragraph IV that the patent is invalid, unenforceable, or will not be infringed.[3]

The principal Paragraph IV arguments would likely include:

Non-infringement

A generic applicant could argue that its product:

• Does not use a substantially homogeneous melt;
• Does not contain both the required wax and fatty-acid components;
• Does not form solid microparticles from the melt;
• Is not cured for at least approximately 48 hours;
• Uses a different thermal process;
• Does not meet the claimed dissolution-stability limitations;
• Does not contain oxycodone in the claimed fatty-acid or wax environment.

Invalidity for anticipation

Anticipation would require a single prior-art reference to disclose every limitation, including the curing period and relevant thermal range. The narrow combination of lipid melt processing, microparticles, inversion-temperature curing, and six-month dissolution performance may make a complete anticipation reference difficult to identify, but the result depends on the patent’s full prosecution history and prior-art record.

Invalidity for obviousness

The strongest obviousness theory would combine prior art relating to:

• Lipid-based drug microparticles;
• Waxes and fatty acids as release-modifying excipients;
• Melt congealing or spray congealing;
• Thermal curing;
• Stability improvement;
• Oxycodone multiparticulate dosage forms.

The patentee would likely rely on the specific inversion-temperature relationship, the minimum curing duration, and the dissolution-stability results as evidence of a non-obvious process and unexpected performance.[4]

Written-description and enablement issues

Potential challenges could focus on the breadth of “one or more drugs,” “one or more waxes,” “one or more fatty acids,” and “substantially homogeneous form.” The question would be whether the specification teaches the full claimed genus without undue experimentation.

What litigation and settlement issues should be reviewed?

A complete litigation review should search:

• District court complaints and opinions;
• Federal Circuit decisions;
• ANDA litigation under 21 U.S.C. § 355(j);
• Inter partes review petitions and institution decisions;
• Post-grant review records;
• Paragraph IV notice letters;
• Consent judgments;
• Generic-launch settlement agreements;
• License and supply agreements involving the patent family.

A settlement can affect commercial entry even when the patent remains facially valid. Important terms may include:

• Licensed entry date;
• Authorized-generic rights;
• Royalty rates;
• Geographic restrictions;
• Product limitations;
• Manufacturing-source restrictions;
• Acceleration clauses;
• Covenants not to sue.

The supplied claim set does not identify any litigation, Paragraph IV filing, settlement, or license. Those events cannot be inferred from the patent claims.

How strong is the patent estate?

The patent appears strongest against a competitor that reproduces the complete technical architecture:

1. Oxycodone;
2. Myristic or stearic acid;
3. Pharmaceutically acceptable wax;
4. Homogeneous melt;
5. Solid microparticles;
6. At least 48 hours of controlled curing;
7. Capsule or pharmaceutical composition use.

Its strongest claim features are the specific oxycodone embodiments and the measurable curing and dissolution conditions. Its principal weaknesses are the potential difficulty of proving process history, the broad functional language, and the possibility of designing around the lipid system or curing sequence.

Risk factor	Assessment
Composition overlap	Moderate to high if the competitor uses the claimed lipid microparticles
Process proof	Moderate difficulty
Design-around potential	Meaningful
Dissolution limitation proof	Technical and protocol-sensitive
Oxycodone commercial relevance	High for matching multiparticulate products
Relevance to ordinary oxycodone generics	Low
Relevance to biologics or biosimilars	None
Geographic scope	United States only
Manufacturing-barrier strength	Moderate, dependent on process evidence

What is the geographic coverage?

US Patent 9,737,530 provides rights only in the United States. It does not establish protection in Canada, Europe, Japan, China, or other markets.

International protection must be assessed through the patent family. Relevant checks include:

• PCT application and international publication;
• National-phase entries;
• European Patent Office family members;
• Canadian, Australian, Japanese, and Chinese counterparts;
• Continuation and divisional applications;
• Abandoned applications that may contain broader or alternative claims.

A US patent can create a US manufacturing and sale barrier even when no foreign counterpart survives. Conversely, a foreign family member may expire, be narrowed, or be revoked on a different schedule.

What generic launch scenarios exist?

Scenario 1: Non-infringing conventional oxycodone product

A conventional tablet or capsule that lacks the claimed cured lipid microparticles may launch without practicing this patent, subject to other patents and FDA requirements.

Scenario 2: Same active ingredient, different delivery platform

A polymeric, ion-exchange, coated-pellet, or solvent-processed formulation may avoid the patent if it does not satisfy the melt, wax, fatty-acid, and curing limitations.

Scenario 3: Matching lipid microparticle product

A generic that reproduces the oxycodone-myristic-acid or oxycodone-stearic-acid platform faces the highest infringement exposure. A Paragraph IV challenge would likely be necessary if the patent is listed and relevant to the reference product.

Scenario 4: At-risk launch

An applicant could launch after a Paragraph IV certification while litigation remains pending. Exposure would depend on the patent’s remaining term, the likelihood of a preliminary injunction, damages, and the commercial value of the product.

Key Takeaways

• US Patent 9,737,530 protects cured drug-loaded lipid microparticles, not oxycodone generally.
• Claim 1 requires a homogeneous melt, solid microparticle formation, optional formulation, and curing for at least approximately 48 hours.
• Claims 7 and 15 specifically target oxycodone with myristic acid; claim 8 covers oxycodone with stearic acid.
• Claims 2 through 6 add dissolution-stability requirements after six months at 25°C and 60% relative humidity.
• The composition claims may be more useful than the process claims when manufacturing records are unavailable.
• The patent is most relevant to extended-release, multiparticulate, or abuse-deterrent oxycodone products.
• Ordinary oxycodone generics that do not use the claimed lipid microparticle platform present lower risk under this patent.
• The patent’s exact expiration date requires confirmation from USPTO term data and any terminal disclaimer or patent-term adjustment.
• Orange Book status, Paragraph IV activity, litigation, settlements, licensing, and foreign counterparts cannot be established from the claim text alone.

FAQs

Does US Patent 9,737,530 cover oxycodone hydrochloride?

It may cover an oxycodone formulation using the claimed wax, fatty-acid, melt-microparticle, and curing architecture. It does not claim oxycodone hydrochloride as a standalone chemical entity.

Can a manufacturer avoid the patent by curing for less than 48 hours?

A process that cures for materially less than the claimed minimum may avoid the literal curing limitation, but other claims, equivalents, continuation patents, or separate formulation patents could remain relevant.

Is a capsule automatically infringing if it contains cured microparticles?

No. The capsule must contain a composition or microparticles meeting the applicable claim limitations. Capsule form alone does not establish infringement.

Does the patent create biosimilar risk?

No meaningful biosimilar risk exists because the claims concern small-molecule drug formulations and oxycodone delivery systems, not biologic molecules or biosimilar products.

Can FDA approval override this patent?

No. FDA approval and patent rights are separate regimes. FDA approval does not authorize infringement of an enforceable patent, while patent expiration does not eliminate the need to satisfy FDA requirements.

References

1. United States Patent and Trademark Office. (n.d.). Patent term calculator and patent term adjustment information. https://www.uspto.gov
2. U.S. Food and Drug Administration. (n.d.). Approved drug products with therapeutic equivalence evaluations: Orange Book. https://www.fda.gov
3. Federal Food, Drug, and Cosmetic Act, 21 U.S.C. § 355(j).
4. United States Patent and Trademark Office. (n.d.). Patent examination guidelines and MPEP provisions concerning anticipation, obviousness, written description, and enablement. https://www.uspto.gov

Drugs Protected by US Patent 9,737,530

Applicant	Tradename	Generic Name	Dosage	NDA	Approval Date	TE	Type	RLD	RS	Patent No.	Patent Expiration	Product	Substance	Delist Req.	Patented / Exclusive Use	Submissiondate
Collegium Pharm Inc	XTAMPZA ER	oxycodone	CAPSULE, EXTENDED RELEASE;ORAL	208090-001	Apr 26, 2016		RX	Yes	No			Y			MANAGEMENT OF PAIN SEVERE ENOUGH TO REQUIRE DAILY, AROUND-THE-CLOCK, LONG-TERM OPIOID TREATMENT AND FOR WHICH ALTERNATIVE TREATMENT OPTIONS ARE INADEQUATE
Collegium Pharm Inc	XTAMPZA ER	oxycodone	CAPSULE, EXTENDED RELEASE;ORAL	208090-002	Apr 26, 2016		RX	Yes	No			Y			MANAGEMENT OF PAIN SEVERE ENOUGH TO REQUIRE DAILY, AROUND-THE-CLOCK, LONG-TERM OPIOID TREATMENT AND FOR WHICH ALTERNATIVE TREATMENT OPTIONS ARE INADEQUATE
Collegium Pharm Inc	XTAMPZA ER	oxycodone	CAPSULE, EXTENDED RELEASE;ORAL	208090-003	Apr 26, 2016		RX	Yes	No			Y			MANAGEMENT OF PAIN SEVERE ENOUGH TO REQUIRE DAILY, AROUND-THE-CLOCK, LONG-TERM OPIOID TREATMENT AND FOR WHICH ALTERNATIVE TREATMENT OPTIONS ARE INADEQUATE
Collegium Pharm Inc	XTAMPZA ER	oxycodone	CAPSULE, EXTENDED RELEASE;ORAL	208090-004	Apr 26, 2016		RX	Yes	No			Y			MANAGEMENT OF PAIN SEVERE ENOUGH TO REQUIRE DAILY, AROUND-THE-CLOCK, LONG-TERM OPIOID TREATMENT AND FOR WHICH ALTERNATIVE TREATMENT OPTIONS ARE INADEQUATE
Collegium Pharm Inc	XTAMPZA ER	oxycodone	CAPSULE, EXTENDED RELEASE;ORAL	208090-005	Apr 26, 2016		RX	Yes	Yes			Y			MANAGEMENT OF PAIN SEVERE ENOUGH TO REQUIRE DAILY, AROUND-THE-CLOCK, LONG-TERM OPIOID TREATMENT AND FOR WHICH ALTERNATIVE TREATMENT OPTIONS ARE INADEQUATE

International Family Members for US Patent 9,737,530

Country	Patent Number	Estimated Expiration	Supplementary Protection Certificate	SPC Country	SPC Expiration
World Intellectual Property Organization (WIPO)	2017222575