U.S. Patent 11,278,544: Claim Scope, Contrave Patent Landscape, and Generic Entry Risk

U.S. Patent 11,278,544 is a method-of-treatment patent covering the use of combined bupropion and naltrexone to treat overweight or obesity. Its central limitation is a therapeutically effective dose of 30-500 mg of bupropion and 5-50 mg of naltrexone, with bupropion in a sustained-release formulation. The patent does not require a particular brand, tablet design, release profile, dosing schedule, or fixed ratio unless a dependent claim adds that limitation.

The patent is relevant to Contrave, the FDA-approved extended-release combination of naltrexone hydrochloride and bupropion hydrochloride. Contrave's labeled maximum daily dose is 32 mg of naltrexone hydrochloride and 360 mg of bupropion hydrochloride, administered as four extended-release tablets per day.[2]

What does U.S. Patent 11,278,544 protect?

The patent protects a therapeutic method, not the active ingredients as chemical compounds. A potentially infringing practice must satisfy every limitation of an asserted claim.

Claim	Principal limitation	Scope
1	Treating overweight or obesity with 30-500 mg bupropion and 5-50 mg naltrexone; bupropion must be sustained release	Broad independent method claim
2	Naltrexone also is in a sustained-release formulation	Narrows claim 1
3	Bupropion dose is 30-300 mg	Narrows the bupropion range
4	Both agents are administered simultaneously	Covers concurrent administration
5	Both agents are supplied in one oral dosage form	Covers a combined tablet or other single oral form
6	Naltrexone is administered before bupropion	Covers sequential dosing in that order
7	Naltrexone is administered after bupropion	Covers the reverse sequential order

The independent claim has four principal elements:

A patient in need of treatment.
The patient is overweight or obese.
The patient receives 30-500 mg of bupropion and 5-50 mg of naltrexone, or pharmaceutically acceptable salts.
The bupropion is in a sustained-release formulation.

The claim does not expressly require that naltrexone be sustained release, although claim 2 adds that limitation. It also does not require simultaneous administration, a single tablet, a specific bupropion-to-naltrexone ratio, a particular titration schedule, or a specific clinical endpoint.

How broad is independent claim 1?

Claim 1 is materially broader than the commercial Contrave regimen in several respects. Contrave uses a fixed extended-release tablet containing 8 mg of naltrexone hydrochloride and 90 mg of bupropion hydrochloride. The approved maintenance dose is two tablets twice daily, equivalent to 32 mg of naltrexone hydrochloride and 360 mg of bupropion hydrochloride per day.[2]

Claim 1 reaches beyond that product because:

The bupropion range extends to 500 mg.
The naltrexone range extends to 50 mg.
Only bupropion must be sustained release.
The two ingredients may be administered in separate dosage forms.
The agents need not be administered simultaneously.
The claim covers salts, not only the hydrochloride salts used in Contrave.
The claim covers treatment of overweight as well as obesity.

A competitor could therefore fall within claim 1 even if it does not copy Contrave's tablet, excipient system, tablet strength, or twice-daily schedule.

The term "comprising" also makes the claim open-ended. Additional active ingredients, excipients, dosage units, or treatment steps generally would not avoid the claim if the recited bupropion, naltrexone, formulation, dose, and disease-treatment limitations remain present.

What formulations are protected by the patent?

The formulation protection is limited but commercially important.

Bupropion sustained release

Claim 1 requires sustained-release bupropion. The claim does not expressly define a dissolution profile, polymer matrix, coating technology, release duration, particle size, or manufacturing process. A range of sustained-release systems could potentially satisfy the limitation, including matrix tablets, coated multiparticulates, and other oral controlled-release systems.

The claim does not require sustained-release naltrexone. A product containing extended-release bupropion and immediate-release naltrexone could potentially satisfy claim 1, assuming the dose and treatment limitations are met.

Both ingredients sustained release

Claim 2 requires sustained release for both active ingredients. This claim is narrower and more closely aligned with a dual extended-release product such as Contrave.

Single oral dosage form

Claim 5 requires both ingredients to be provided in a single oral dosage form. A fixed-dose combination tablet is the clearest example. The claim does not appear limited to a particular tablet weight, strength, release mechanism, or inactive ingredient.

Separate bupropion and naltrexone products administered during the same treatment course may avoid claim 5, but they could remain within claim 1 or claim 4.

Does the patent cover method-of-use activity?

Yes. The claims are method-of-use claims directed to treatment of overweight or obesity.

The patent does not expressly recite:

A minimum percentage of body-weight loss.
A specific body-mass-index threshold.
A requirement for diet and exercise.
A treatment duration.
A requirement that the patient have a particular obesity-related comorbidity.
A specific prescriber, care setting, or route other than the oral dosage form stated in claim 5.

A product label that expressly instructs use of sustained-release bupropion with naltrexone for overweight or obesity could create significant induced-infringement exposure if the remaining limitations are met. Liability would depend on the label language, product configuration, actual use, and the applicable infringement evidence.

How does the patent compare with Contrave's FDA-approved regimen?

Attribute	Claim 1 of U.S. 11,278,544	Contrave label
Bupropion	30-500 mg	360 mg daily at maintenance
Naltrexone	5-50 mg	32 mg daily at maintenance
Bupropion release	Sustained release required	Extended release
Naltrexone release	Not required by claim 1	Extended release
Dosage form	Not required	Single extended-release tablet
Administration	Flexible	Two tablets twice daily at maintenance
Indication	Overweight or obesity	Chronic weight management in adults with obesity or overweight plus a related condition
Active ingredients	Bupropion or salt; naltrexone or salt	Bupropion hydrochloride and naltrexone hydrochloride

The approved Contrave regimen appears to fall within claim 1 and claim 2. It also falls within claim 3 because 360 mg of daily bupropion exceeds the 30-300 mg range in claim 3. Claim 3 is therefore not aligned with the labeled maximum maintenance dose if the dose is measured on a total daily basis. It may apply to regimens using 300 mg or less of bupropion.

What are the principal design-around paths?

A competitor evaluating a non-infringing regimen would likely examine the following variables:

Design-around variable	Potential effect
Use bupropion without sustained release	Could avoid claim 1, subject to claim construction and product facts
Use bupropion below 30 mg	Could avoid the recited bupropion range
Use naltrexone below 5 mg or above 50 mg	Could avoid the recited naltrexone range
Treat a condition other than overweight or obesity	Could avoid the claimed indication
Use a non-bupropion antidepressant with naltrexone	Outside the literal active-ingredient combination
Use separate products	Could avoid claim 5 but not necessarily claims 1 or 4
Administer only one active ingredient	Outside the combination claims
Use a non-oral dosage form	May avoid claim 5, but claim 1 does not expressly require a single oral dosage form

The most consequential design-around issue is the sustained-release limitation for bupropion. A product that uses immediate-release bupropion could present a stronger non-infringement position, although equivalence, prosecution history, and the patent's specification would remain relevant.

Dose avoidance is less straightforward for commercial products. The patented ranges are broad enough to encompass many clinically plausible combinations, including the approved Contrave dose. A small dose adjustment may not provide a commercially useful or clinically acceptable alternative.

What is the Orange Book status of U.S. Patent 11,278,544?

The Orange Book status must be evaluated separately from the patent's technical scope. A patent can cover a method associated with an approved drug without being listed in the Orange Book. Orange Book listing depends on FDA listing practices, the drug product, the approved labeling, and the patent's relationship to the approved product.[3]

For Contrave, the relevant regulatory questions are:

Whether U.S. 11,278,544 is listed against Contrave.
Whether its use code covers treatment of obesity or overweight.
Whether the listed claims correspond to the approved indication.
Whether the patent has been delisted, expired, or subject to a statutory disclaimer.
Whether an ANDA applicant must address it with a Paragraph IV certification.

A definitive Orange Book conclusion cannot be derived from the claim text alone. The FDA's current Orange Book entry and patent listing must control.

When does U.S. Patent 11,278,544 lose exclusivity?

The patent issued on March 29, 2022.[1] Its enforceable expiration date depends on the patent family's earliest effective nonprovisional filing date, patent-term adjustment, patent-term extension, terminal disclaimers, and any applicable regulatory extension.

The issue date is not the expiration date. A continuation patent generally shares the term of its parent application and does not receive a new 20-year term merely because it issued later. A reliable expiration analysis therefore requires the USPTO patent record and patent-term data, rather than the claims alone.

The economic significance of the patent depends on whether it remains enforceable after other Contrave patents expire. A later-expiring method patent can delay practical generic entry if it is listed in the Orange Book and tied to the approved use. If it is not listed, it may still support infringement litigation but would not necessarily create the same ANDA certification and 30-month-stay framework.

What Paragraph IV risks exist for generic bupropion-naltrexone products?

A generic applicant seeking approval for a product equivalent to Contrave could face several certification issues:

Paragraph III certification if the applicant accepts a later launch date.
Paragraph IV certification alleging that a listed patent is invalid, unenforceable, or not infringed.
A section viii statement carving out a patented method of use, if the remaining approved uses can be marketed lawfully.
A product-label strategy that removes the patented use, subject to FDA approval and induced-infringement risk.

Because claims 1-7 are method claims, a generic applicant may focus on label carve-outs, dosing instructions, and whether the proposed product's labeling induces treatment of overweight or obesity. A carve-out is most difficult when the patented method substantially overlaps the only commercial use of the reference product.

Which companies are challenging the Contrave patent estate?

The relevant competitive field includes generic pharmaceutical companies capable of supplying:

Bupropion extended-release products.
Naltrexone products.
Fixed-dose bupropion-naltrexone combinations.
Obesity medicines with different mechanisms, including GLP-1 receptor agonists and other incretin-based therapies.

Public litigation and Paragraph IV conclusions must be tied to individual docket numbers, ANDA numbers, and FDA records. The existence of a generic bupropion or naltrexone product does not establish a challenge to U.S. 11,278,544. A generic company can market each component separately without necessarily seeking approval for the patented combination method.

How strong is the patent estate?

The patent is strongest against a product that:

Uses sustained-release bupropion.
Uses 5-50 mg of naltrexone.
Is labeled for overweight or obesity.
Uses the active ingredients together in a chronic weight-management regimen.
Supplies both ingredients in a single oral dosage form.

The patent is weaker against:

Immediate-release bupropion regimens.
Products outside the claimed dose ranges.
Products with a non-obesity indication.
Separate-component products with no combination-use instructions.
Products whose labeling omits or carves out the patented method.

The claims are broad in therapeutic and dosing scope but relatively narrow in requiring bupropion sustained release. They do not claim the molecular compounds, a specific tablet architecture, or a manufacturing process. Their commercial value therefore depends heavily on whether a competing obesity product uses the same pharmacologic combination and how its FDA label instructs use.

What manufacturing and intellectual-property barriers remain?

The patent does not appear, from the supplied claims, to claim:

Manufacture of bupropion.
Manufacture of naltrexone.
A specific sustained-release polymer.
A specific tablet-compression process.
A specific dissolution profile.
A particular salt-selection process.
A fixed-dose combination composition.

Separate formulation, composition, process, and method patents may exist in the broader Contrave estate. Those patents must be analyzed independently. Avoiding U.S. 11,278,544 would not eliminate infringement exposure under another patent covering the tablet composition, release profile, manufacturing process, or approved method of use.

Key Takeaways

U.S. 11,278,544 is a method-of-treatment patent for combined bupropion and naltrexone in overweight or obese patients.
Claim 1 is the commercial center of gravity and requires sustained-release bupropion.
The claimed dose ranges encompass the approved Contrave maintenance regimen.
Claim 2 reaches dual sustained-release products.
Claim 5 targets single oral dosage forms, including fixed-dose combination tablets.
Separate administration can avoid claim 5 but may remain within claims 1, 4, 6, or 7.
The patent does not claim the active molecules, a particular formulation technology, or a manufacturing process.
Orange Book listing, patent-term status, Paragraph IV exposure, and generic launch timing require review of the current FDA and USPTO records.
The strongest generic design-around strategy is likely to focus on the sustained-release bupropion limitation, dose boundaries, labeling, or a non-overlapping indication.

Frequently Asked Questions

Does U.S. Patent 11,278,544 cover Contrave itself?

The approved Contrave regimen appears to fall within the technical scope of claims 1 and 2 because it combines sustained-release bupropion and sustained-release naltrexone within the claimed dose ranges for obesity or overweight treatment.

Does the patent require one tablet containing both drugs?

No. Claim 1 does not require a single dosage form. Claim 5 adds that limitation. A two-product regimen may avoid claim 5 while still implicating broader claims.

Can a generic sell bupropion and naltrexone separately?

Separate marketing of the individual drugs is not automatically within claim 5. Risk depends on the products' labeling, intended use, dosing instructions, actual combination use, and other patents in the estate.

Does claim 3 cover the standard Contrave maintenance dose?

Claim 3 recites 30-300 mg of bupropion. The standard labeled maintenance dose is 360 mg of bupropion hydrochloride per day, so the labeled maintenance regimen does not fall within that specific bupropion range if measured as total daily dose.

Is avoiding the patent enough to launch a competing obesity product?

No. Other composition, formulation, process, and method-of-use patents may affect launch. Regulatory exclusivity, Orange Book listings, Paragraph IV litigation, labeling restrictions, and settlement agreements also can determine launch timing.

References

United States Patent and Trademark Office. (2022). U.S. Patent No. 11,278,544, methods of treating overweight or obesity. U.S. Department of Commerce.
U.S. Food and Drug Administration. (2023). Contrave (naltrexone hydrochloride and bupropion hydrochloride) extended-release tablets: Prescribing information. FDA.
U.S. Food and Drug Administration. (2024). Approved drug products with therapeutic equivalence evaluations: Orange Book. FDA.
35 U.S.C. §§ 154, 271, 355. (2024). United States Code.

Country	Patent Number	Estimated Expiration	Supplementary Protection Certificate	SPC Country	SPC Expiration
European Patent Office	2316456	⤷ Start Trial	CA 2017 00062	Denmark	⤷ Start Trial
European Patent Office	2316456	⤷ Start Trial	300918	Netherlands	⤷ Start Trial
European Patent Office	2316456	⤷ Start Trial	122017000109	Germany	⤷ Start Trial
European Patent Office	2316456	⤷ Start Trial	LUC00054	Luxembourg	⤷ Start Trial
European Patent Office	2316456	⤷ Start Trial	2017C/064	Belgium	⤷ Start Trial
>Country	>Patent Number	>Estimated Expiration	>Supplementary Protection Certificate	>SPC Country	>SPC Expiration

Details for Patent: 11,278,544

Summary for Patent: 11,278,544