United States Patent 9,633,575: Scope, Claim Construction, Exclusivity, and Contrave Patent Landscape

U.S. Patent No. 9,633,575 protects a narrow cardiovascular-risk method of using the extended-release naltrexone/bupropion combination marketed as Contrave. The independent claim requires an overweight or obese patient with established cardiovascular disease and specified atherosclerotic risk characteristics, treated with 32 mg/day sustained-release naltrexone and 360 mg/day sustained-release bupropion. The patent does not broadly cover all obesity treatment with Contrave, the drug combination itself, or every patient with cardiovascular risk.

The patent is commercially important because it targets the population implicated by Contrave's cardiovascular-outcomes evidence and can create method-of-use exposure for an ANDA applicant that seeks labeling covering the patented population. The practical strength of the patent depends on its Orange Book status, the scope of generic labeling, the validity of its cardiovascular-risk limitations, and whether infringement can be shown from the generic label and prescribing behavior.

What patent is U.S. 9,633,575 and what does it protect?

U.S. Patent 9,633,575 is a method-of-treatment patent covering the use of sustained-release naltrexone and sustained-release bupropion in overweight or obese subjects at increased risk of a major adverse cardiovascular event, or MACE.

Item	Details
Patent	U.S. Patent No. 9,633,575
Issue date	April 25, 2017
Patent type	Method of treatment
Active ingredients	Sustained-release naltrexone and sustained-release bupropion
Daily dose	32 mg naltrexone and 360 mg bupropion
Commercial product	Contrave
Standard tablet strength	8 mg naltrexone / 90 mg bupropion extended release
Standard daily administration	Two tablets twice daily at maintenance dose
Primary indication in claim 1	Overweight or obesity with established cardiovascular disease and specified risk factors
MACE definition in claim 11	Cardiovascular death, nonfatal myocardial infarction, or nonfatal stroke
Earliest apparent patent expiration	Approximately March 2031, subject to the USPTO term record and any applicable adjustment

The patent's claims are narrower than a conventional obesity-treatment patent. They are directed to a selected patient population and a defined cardiovascular-risk setting. The claims also incorporate treatment duration, behavioral support, tablet composition, weight-loss results, and cardiovascular-outcome limitations.

The patent should be analyzed separately from patents that protect:

the naltrexone/bupropion combination;
the extended-release formulation;
tablet manufacturing;
dose escalation;
obesity treatment generally;
or the Contrave product as listed in the FDA Orange Book.

What are the required elements of independent claim 1?

Claim 1 requires each of the following elements:

The patient is overweight or obese.
The patient has been identified as being at increased risk of a MACE.
The patient has cardiovascular disease.
The patient has at least one specified cardiovascular or atherosclerotic risk characteristic.
The patient receives 32 mg/day sustained-release naltrexone, or a pharmaceutically acceptable salt.
The patient receives 360 mg/day sustained-release bupropion, or a pharmaceutically acceptable salt.

The cardiovascular-risk characteristics include:

documented myocardial infarction more than three months before identification;
prior coronary revascularization;
prior carotid or peripheral revascularization;
angina with specified ischemic findings;
ankle-brachial index below 0.9;
or more than 50% stenosis in a coronary, carotid, or lower-extremity artery.

The claim therefore does not cover a patient merely because the patient has obesity, hypertension, dyslipidemia, or a general risk of cardiovascular disease. The patient must fall within the claim's defined cardiovascular-disease framework.

Why the three-month myocardial-infarction limitation matters

The claim excludes a myocardial infarction occurring three months or less before the identification date because it requires a history of documented myocardial infarction greater than three months before identification. A patient with a recent infarction may still satisfy another listed risk factor, but the infarction alone would not satisfy that particular alternative.

Why the exact dose matters

The claim requires the full maintenance dose of 32 mg/day naltrexone and 360 mg/day bupropion. A generic product or prescribing regimen using a lower dose may avoid literal infringement of claim 1, although other claims or other patents could remain relevant.

The dose corresponds to four 8 mg/90 mg extended-release tablets per day. Claim 10 and claims 17-19 reinforce this dosing and tablet configuration.

How do claims 2 through 19 narrow the patent?

The dependent claims add limitations rather than expanding the scope of claim 1.

Claims	Added limitation	Commercial or legal effect
2	Excludes a patient with type 2 diabetes plus at least two listed risk factors	Narrows the eligible population
3	Treatment for at least 16 weeks	Requires a minimum treatment period
4-9	Web-based or telephone-based weight-management support	Creates potential exposure where a manufacturer or provider promotes coaching tools
10	8 mg/90 mg sustained-release tablet	Links the method to the commercial dosage unit
11	MACE includes cardiovascular death, nonfatal MI, or nonfatal stroke	Defines the adverse-event category
12	At least 5% weight loss	Requires an outcome in the treated patient
13	No intensive behavioral-modification program	Narrows the treatment setting
14	Treatment does not increase MACE risk	Adds a safety-result limitation
15	Treatment decreases MACE risk	Adds an efficacy-result limitation
16	MACE limited to cardiovascular death	Narrows claim 11
17	Two 8 mg doses of naltrexone and two 90 mg doses of bupropion twice daily	Expressly states the four-tablet daily regimen
18	Cardiovascular death plus the twice-daily dose regimen	Narrower cardiovascular-death claim
19	Claim 18 plus the 8 mg/90 mg tablet	Narrowest tablet-and-outcome combination

Claims 4 through 9 are unusual in that they tie pharmacologic treatment to digital or telephone-based weight-management support. These claims may have more relevance to a branded service model, disease-management program, or manufacturer-sponsored support program than to a bare generic product sale.

What does the patent cover commercially?

The commercial core is the use of full-dose Contrave in obese or overweight patients with established cardiovascular disease. The patent has three principal commercial applications.

Use in patients with established cardiovascular disease

The strongest practical reading of claim 1 covers patients with prior infarction, revascularization, measurable arterial stenosis, or documented ischemic disease. It is not limited to patients who have already experienced a MACE during Contrave treatment.

Use at the full maintenance dose

A patient must receive the 32 mg/360 mg daily regimen. The patent therefore aligns closely with the standard Contrave maintenance dose described in the FDA-approved labeling. The product label recommends a gradual dose escalation to two tablets in the morning and two tablets in the evening by week four.[1]

Use in a cardiovascular-outcomes context

Claims 14 and 15 address whether the treatment increases or decreases MACE risk. Claim 1 itself does not require proof that the patient's cardiovascular risk actually falls. It requires the selection of a patient identified as being at increased risk and administration of the specified regimen.

That distinction is important. A claim directed to treatment of a selected high-risk patient may be infringed without the patient experiencing a cardiovascular event, while claims requiring a reduction or nonincrease in risk may require more difficult proof concerning patient outcomes, clinical data, or the meaning of the claim language.

What is the Orange Book status of U.S. 9,633,575?

U.S. Patent 9,633,575 should be reviewed in the FDA Orange Book patent listing for NDA 200063, the Contrave application. The Orange Book determines whether the patent is formally listed against the approved drug and whether an ANDA applicant must address it through a paragraph III certification, paragraph IV certification, or a section viii statement.[2]

The key distinction is:

If listed as a use patent, a generic applicant may attempt a section viii statement to carve out the patented method from its labeling.
If the applicant's proposed label still encourages or includes the patented use, the patent holder may assert induced-infringement or contributory-infringement theories.
If the applicant submits a paragraph IV certification, the patent holder may bring an action under the Hatch-Waxman statute, potentially triggering a 30-month stay.[3]

An Orange Book listing does not establish validity or enforceability. It establishes the patent's role in FDA's ANDA certification process.

The relevant regulatory questions are:

Is U.S. 9,633,575 listed against Contrave's NDA?
Is it listed as a method-of-use patent or under another patent-use category?
What use code accompanies the listing?
Does the generic applicant's proposed labeling overlap that use code?
Has the patent holder accepted a section viii carve-out?
Has a paragraph IV notice letter triggered litigation?

The patent's use code is commercially important because a narrow, accurately drafted use code can permit a generic applicant to omit the patented cardiovascular-risk indication from its label. A broad or ambiguous use code can increase dispute risk.

When does U.S. 9,633,575 lose exclusivity?

The patent's projected ordinary term runs approximately 20 years from its earliest effective nonprovisional filing date. Public patent records associate the family with a March 2011 priority period, producing an expected expiration around March 2031, subject to the official USPTO term calculation.[4]

The effective exclusivity date may differ because of:

patent term adjustment;
patent term extension;
terminal disclaimers;
disclaimer of remaining term;
post-grant proceedings;
or a court judgment affecting enforceability.

Patent expiration does not necessarily equal immediate generic market entry. A generic applicant may launch earlier after:

a successful paragraph IV challenge;
a court ruling of invalidity or noninfringement;
a settlement permitting an agreed launch date;
or approval with a lawful section viii carve-out.

Regulatory exclusivity versus patent exclusivity

Contrave's FDA regulatory exclusivity is distinct from U.S. 9,633,575. New-drug exclusivity periods generally expire before a patent with an approximately 2031 term. Regulatory exclusivity blocks certain FDA approvals for a defined period; patent rights can block commercial activity after approval.

How strong is the patent estate for Contrave?

The Contrave estate should be separated into four layers.

Combination and formulation patents

These patents can cover the use of naltrexone and bupropion together, extended-release delivery, tablet composition, release characteristics, and manufacturing parameters. They may present greater generic risk than a single patient-selection method patent because a generic product must generally use the same active ingredients and dosage form.

Dose and titration patents

The commercial regimen uses a defined tablet strength and gradual titration to a four-tablet daily dose. Patents directed to dosing schedules can create overlap even where a generic applicant attempts to limit use claims.

Method-of-use patents

U.S. 9,633,575 is in this category. It targets a selected patient population rather than the physical product. It may be vulnerable to a carve-out if the patented use is separable from the broader obesity indication.

Support-program claims

Claims 4-9 add coaching, web tools, food recording, activity recording, and calorie databases. These claims are less likely to block a conventional ANDA product by themselves. They may matter where the brand or a licensee operates a coordinated digital weight-management program.

What FDA regulatory issues affect infringement and market entry?

The FDA-approved Contrave label contains clinically important restrictions and warnings. Contrave is contraindicated in uncontrolled hypertension and carries warnings concerning increases in blood pressure and heart rate, seizures, hepatotoxicity, opioid use, and neuropsychiatric effects.[1]

The FDA label also states that the effect of Contrave on cardiovascular morbidity and mortality has not been established. The LIGHT cardiovascular-outcomes trial was terminated after a sponsor disclosure concerning release of interim data, and the FDA required additional postmarketing cardiovascular-outcomes work.[5]

This regulatory history affects claims 14 and 15:

Claim 14 requires that treatment does not increase MACE risk.
Claim 15 requires that treatment decreases MACE risk.
The approved label does not necessarily affirmatively promote a cardiovascular-risk reduction claim.
A generic applicant may argue that it cannot induce infringement of claims 14 or 15 without labeling that represents a cardiovascular benefit or safety result.

Claim 1 is potentially stronger than claims 14 and 15 from an infringement perspective because it focuses on patient selection and administration, not a claimed cardiovascular benefit.

What paragraph IV challenges and litigation risks exist?

A generic applicant seeking approval for naltrexone/bupropion extended-release tablets must address each Orange Book-listed patent. The applicant may use:

paragraph III certification, agreeing not to market until patent expiration;
paragraph IV certification, asserting invalidity, unenforceability, or noninfringement;
or a section viii statement carving out a patented method of use.

For U.S. 9,633,575, the principal generic arguments would likely involve:

Noninfringement through label carve-out

A generic label could omit language directed to patients with established cardiovascular disease or to cardiovascular-outcomes treatment. The applicant would argue that its label does not encourage the patented method.

Claim construction

The parties may dispute the meaning of:

"increased risk of a major adverse cardiovascular event";
"cardiovascular disease";
"identified as being at increased risk";
"at least one risk factor";
and the timing requirements for prior infarction or stenosis.

Written description and enablement

The patent claims a broad class of high-risk patients and asserts that treatment does not increase or may decrease MACE risk. A challenger could argue that the specification does not adequately support the full breadth of those results across all claimed patients, doses, cardiovascular conditions, and treatment settings.

Obviousness

A challenger could combine earlier obesity-treatment disclosures, known naltrexone/bupropion dosing, cardiovascular-risk patient populations, and clinical-trial data. The patentee would respond that the claimed patient selection and cardiovascular outcome were not predictable from the prior art.

Induced infringement

Even if the generic label omits the patented use, actual prescribing by physicians does not automatically establish induced infringement. The patent holder generally must show that the generic manufacturer actively encouraged the patented use, not merely that physicians independently used the product for that purpose.

No reliable conclusion about a current paragraph IV challenger, settlement date, or active litigation posture should be drawn from the patent claims alone. Those facts depend on current Orange Book records, FDA certification notices, PACER filings, and settlement documents.

Does the patent create biosimilar risk?

No. Contrave is a small-molecule drug product, not a biologic. A competing naltrexone/bupropion product would proceed through the ANDA pathway under section 505(j), not through the biosimilar pathway under section 351(k).

The relevant competitive risks are:

generic tablet approval;
section viii labeling;
paragraph IV litigation;
authorized-generic competition;
formulation workarounds;
and physician use outside the carved-out indication.

How does U.S. 9,633,575 compare with broad Contrave patents?

Issue	U.S. 9,633,575	Broad combination or formulation patent
Protected subject matter	Selected high-risk patient and treatment method	Product, composition, release profile, or general use
Required patient characteristics	Yes	Often no
Required daily dose	Yes	Often yes or formulation-specific
Infringement evidence	Prescription, label, patient selection, administration	Product composition and manufacturing evidence
Section viii carve-out potential	Relatively significant if use is separable	Usually limited
Relevance to generic tablet approval	Important if label overlaps	Often central
Exposure from actual prescribing	Potentially material	Less dependent on physician intent for product claims
Vulnerability	Patient-selection, outcome, written-description issues	Prior-art, formulation, and obviousness issues

The patent is therefore strategically important but not necessarily the strongest barrier in the entire Contrave estate. A generic entrant must analyze all listed patents together. A successful carve-out of U.S. 9,633,575 would not resolve separate formulation or composition patents.

What generic launch scenarios exist?

Scenario 1: Launch after ordinary patent expiration

The generic waits until the relevant listed patents expire. This is the lowest litigation-risk path but delays entry until the applicable patent barrier ends.

Scenario 2: Paragraph IV challenge

The generic certifies that U.S. 9,633,575 is invalid, unenforceable, or not infringed. Litigation may produce an early launch if the generic prevails or reaches a settlement.

Scenario 3: Section viii carve-out

The generic removes the patented high-risk cardiovascular use from its label. This is the most direct route around a narrow method-of-use patent, but it creates risk if the remaining label, promotional materials, or product instructions still encourage the claimed use.

Scenario 4: At-risk launch

The generic launches before final resolution after assessing litigation exposure. This can produce damages, an injunction, and a potential loss of market exclusivity if the patent is upheld.

What is the commercial exposure from U.S. 9,633,575?

The patent does not cover all Contrave revenue. Its revenue exposure is limited to the portion attributable to:

overweight or obese patients with established cardiovascular disease;
the specified cardiovascular-risk characteristics;
the full 32 mg/360 mg daily dose;
and, for dependent claims, the added duration, outcome, or support-program limitations.

The commercial exposure is therefore smaller than the total Contrave market, but the covered population may be clinically important because obesity and cardiovascular disease frequently coexist. A generic company would likely model exposure using prescription data, diagnosis codes, cardiovascular history, dose persistence, and the percentage of prescriptions written for patients with established atherosclerotic disease.

Key Takeaways

U.S. 9,633,575 is a narrow method-of-treatment patent, not a broad composition patent.
Claim 1 requires overweight or obesity, established cardiovascular disease, at least one specified risk characteristic, and full-dose sustained-release naltrexone/bupropion.
The commercial regimen is four 8 mg/90 mg extended-release tablets per day.
Claims 4-9 add web-based and telephone-based weight-management support.
Claims 14 and 15 address whether treatment does not increase or decreases MACE risk and may present greater proof and validity issues.
The patent's projected expiration is approximately March 2031, subject to the official USPTO term record.
A generic applicant may pursue paragraph IV certification or a section viii carve-out, depending on the Orange Book listing and use code.
Contrave is a small-molecule product, so biosimilar law is not relevant.
The patent must be analyzed with separate Contrave composition, formulation, dosing, and manufacturing patents.
The most important practical dispute is whether a generic label and promotional conduct encourage the patented cardiovascular-risk use.

FAQs

Can U.S. 9,633,575 block a generic version of Contrave for ordinary obesity treatment?

Not necessarily. The patent's independent claim requires a patient with defined cardiovascular disease and specified risk characteristics. A generic applicant may seek approval for a noninfringing obesity indication through a section viii carve-out.

Does every patient with hypertension qualify under claim 1?

No. Hypertension alone is not one of the listed claim 1 cardiovascular-disease criteria. Claim 2 addresses hypertension as one of several type 2 diabetes-related risk factors, but it does not convert ordinary hypertension into the cardiovascular-disease requirement of claim 1.

Does a patient need to suffer a heart attack while taking Contrave to infringe claim 1?

No. Claim 1 requires administration to a qualifying high-risk patient. It does not require that the patient experience a MACE during treatment.

Is the 8 mg/90 mg tablet itself protected by U.S. 9,633,575?

Claim 10 and claim 19 use the 8 mg/90 mg tablet as a limitation in a treatment method. They do not, by themselves, create a broad product claim covering every such tablet.

Can a generic manufacturer avoid infringement by omitting cardiovascular-outcomes language?

Possibly, but omission of express language is not automatically dispositive. The full label, prescribing instructions, promotional materials, and any evidence of active encouragement must be assessed against the asserted claims.

Does patent expiration guarantee immediate generic Contrave availability?

No. Approval timing, other listed patents, regulatory requirements, litigation outcomes, settlements, manufacturing readiness, and supply arrangements can delay or affect launch.

References

U.S. Food and Drug Administration. (2023). Contrave (naltrexone hydrochloride and bupropion hydrochloride) extended-release tablets: Prescribing information. https://www.accessdata.fda.gov/drugsatfda_docs/label/2023/200063s020lbl.pdf
U.S. Food and Drug Administration. (2025). Approved drug products with therapeutic equivalence evaluations: Orange Book. https://www.accessdata.fda.gov/scripts/cder/ob/
U.S. Congress. (1984). Drug Price Competition and Patent Term Restoration Act, 21 U.S.C. § 355(j).
United States Patent and Trademark Office. (2017). U.S. Patent No. 9,633,575. https://patents.google.com/patent/US9633575B2/en
U.S. Food and Drug Administration. (2015). FDA statement on terminated cardiovascular outcomes trial for Contrave. https://www.fda.gov/drugs/drug-safety-and-availability/fda-drug-safety-communication/communications-related-contrave-cardiovascular-outcomes-trial

Applicant	Tradename	Generic Name	Dosage	NDA	Approval Date	TE	Type	RLD	RS	Patent No.	Patent Expiration	Product	Substance	Delist Req.	Patented / Exclusive Use	Submissiondate
Azurity	CONTRAVE	bupropion hydrochloride; naltrexone hydrochloride	TABLET, EXTENDED RELEASE;ORAL	200063-001	Sep 10, 2014		RX	Yes	Yes	9,633,575	⤷ Start Trial				FOR CHRONIC WEIGHT MANAGEMENT FOR TREATING OVERWEIGHT OR OBESITY	⤷ Start Trial
>Applicant	>Tradename	>Generic Name	>Dosage	>NDA	>Approval Date	>TE	>Type	>RLD	>RS	>Patent No.	>Patent Expiration	>Product	>Substance	>Delist Req.	>Patented / Exclusive Use	>Submissiondate

PCT Information
PCT Filed	June 05, 2013	PCT Application Number:	PCT/US2013/044368
PCT Publication Date:	December 12, 2013	PCT Publication Number:	WO2013/184837

Country	Patent Number	Estimated Expiration	Supplementary Protection Certificate	SPC Country	SPC Expiration
Argentina	093694	⤷ Start Trial
Argentina	125234	⤷ Start Trial
Australia	2013271622	⤷ Start Trial
Australia	2018203271	⤷ Start Trial
>Country	>Patent Number	>Estimated Expiration	>Supplementary Protection Certificate	>SPC Country	>SPC Expiration

Summary for Patent: 9,633,575