United States Drug Patent 3,980,789: Alprazolam Claims, Scope, Expiration, and Patent Landscape

United States Patent No. 3,980,789 covers pharmaceutical compositions and sleep-induction methods using alprazolam, the compound 8-chloro-1-methyl-6-phenyl-4H-s-triazolo[4,3-a][1,4]benzodiazepine. The patent does not claim alprazolam as a chemical compound. Its claims are limited to specified dosage ranges, pharmaceutical carriers, and administration for inducing sleep.

The patent issued on September 14, 1976, and its pre-1995 patent term expired on September 14, 1993, absent a separate term adjustment or enforceable extension. It therefore provides no current U.S. patent barrier to generic alprazolam. FDA-approved immediate-release and extended-release alprazolam products are subject to the modern generic-drug framework, including ANDA approvals and historical Paragraph IV activity, but US 3,980,789 itself is no longer enforceable.[1][2]

What drug does United States Patent 3,980,789 protect?

US 3,980,789 protects dosage-form and method-of-use applications of alprazolam.

Patent element	Substance
Active ingredient	Alprazolam
Chemical name in claims	8-chloro-1-methyl-6-phenyl-4H-s-triazolo[4,3-a][1,4]benzodiazepine
Salt coverage	Pharmacologically acceptable acid-addition salts
Specifically named salt	Alprazolam hydrobromide
Free-base coverage	Expressly claimed
Indication	Inducing sleep
Dosage-form requirement	Unit dosage form
Carrier requirement	Pharmaceutical carrier
Patent number	US 3,980,789
Issue date	September 14, 1976
U.S. expiration	September 14, 1993, based on the pre-1995 17-year term

Alprazolam is marketed under the Xanax brand and is also available in generic immediate-release tablets, orally disintegrating tablets, and extended-release tablets. The claims in US 3,980,789 are directed to alprazolam use rather than to the Xanax trademark, a particular commercial tablet, or a particular manufacturing process.

How broad are the claims in US 3,980,789?

The patent has six claims divided between pharmaceutical compositions and sleep-induction methods.

Claims 1 through 3: pharmaceutical composition claims

Claim 1 requires all of the following:

A pharmaceutical composition.
A unit dosage form.
Between approximately 0.5 mg and 10 mg of alprazolam or a pharmacologically acceptable acid-addition salt.
A pharmaceutical carrier.
Use for inducing sleep.

Claim 2 narrows claim 1 to the hydrobromic acid-addition salt. Claim 3 narrows claim 1 to alprazolam in the free-base form.

The composition claims are broad as to formulation technology. They do not require a tablet, capsule, solution, suspension, particular excipient, coating, dissolution profile, or release mechanism. A conventional oral tablet could fall within the literal language if it contains the claimed amount of alprazolam and a pharmaceutical carrier.

The claims are narrower than a compound patent because they do not cover every use or every product containing alprazolam. A product containing alprazolam outside the claimed unit-dose range would not literally meet claim 1. A formulation without a pharmaceutical carrier would also raise a claim-scope issue, although most finished pharmaceutical dosage forms would ordinarily include excipients or another carrier component.

Claims 4 through 6: method-of-use claims

Claim 4 covers a process for inducing sleep by administering alprazolam or an acceptable acid-addition salt to a human or animal subject at a dose of approximately 0.005 mg/kg to 0.2 mg/kg of body weight, in association with a pharmaceutical carrier.

Claims 5 and 6 specify the hydrobromide salt and free base, respectively.

The method claims are broader than the fixed-dose composition claims in one respect: they use a weight-based dosing range. For a 50 kg subject, the claimed range corresponds to approximately 0.25 mg to 10 mg. For a 70 kg subject, it corresponds to approximately 0.35 mg to 14 mg. For a 100 kg subject, it corresponds to approximately 0.5 mg to 20 mg.

Subject weight	Claim 4 dose range
50 kg	0.25 to 10 mg
70 kg	0.35 to 14 mg
100 kg	0.5 to 20 mg

The weight-based range overlaps the 0.5 mg-to-10 mg unit-dose range in claim 1, but the two claim categories are legally distinct. Claim 1 is directed to a composition. Claim 4 is directed to an administration process.

What is the claim-construction significance of the dosage ranges?

The dosage limitations are central to infringement analysis.

A composition containing 0.25 mg of alprazolam would fall below claim 1's stated range, even though it could fall within claim 4's method range for a sufficiently heavy patient. Conversely, a 20 mg unit dose would exceed claim 1's fixed-dose range but could fall within claim 4's weight-based range for some patients.

The phrase "about" introduces ordinary claim-construction flexibility around the numerical endpoints. It does not eliminate the dosage limitation. Courts generally assess the scope of "about" in light of the specification, technical measurement practices, formulation variability, and the evidence concerning the invention.[3]

The patent does not specify:

A once-daily or bedtime administration schedule.
A particular treatment duration.
A minimum sleep duration.
A particular patient population.
Oral, parenteral, sublingual, or other administration routes.
Immediate-release or extended-release delivery.
A specific excipient system.
A tablet hardness, dissolution profile, or particle size.
A manufacturing method.
A particular polymorph or crystal form.

This leaves the claims technically broad within their stated dosage and therapeutic limitations, but the patent's expiration removes any present enforcement value.

Does US 3,980,789 claim the alprazolam molecule itself?

No. The patent does not contain a standalone composition-of-matter claim in the claims supplied.

A compound claim would ordinarily recite alprazolam as a chemical entity independent of a dosage form or therapeutic use. US 3,980,789 instead requires alprazolam to be present in a pharmaceutical composition or to be administered for inducing sleep.

That distinction matters commercially. A separate compound patent, process patent, salt patent, polymorph patent, or formulation patent could have created additional protection even if US 3,980,789 expired. Such rights would need to be assessed separately from the claims of this patent.

When did US 3,980,789 lose exclusivity?

The patent expired on September 14, 1993, under the pre-1995 U.S. patent term rule of 17 years from issuance.[1]

Event	Date or status
Patent issued	September 14, 1976
Original pre-1995 term	17 years from issuance
Projected expiration	September 14, 1993
Current enforceability	Expired
Patent-term extension relevance	No current effect identified
Generic entry status	Not blocked by this patent

The FDA approved Xanax tablets under NDA 018276 in 1981. Alprazolam was approved after the Hatch-Waxman amendments and received the standard five-year new chemical entity exclusivity period, subject to the applicable regulatory framework. That exclusivity period expired well before the patent expired, allowing ANDA applicants to pursue generic approval while the patent remained a potential litigation obstacle.[2][4]

The patent’s expiration date is materially earlier than the current 20-year-from-filing term used for most modern U.S. patents because US 3,980,789 falls under the pre-1995 patent-term regime.

What was the FDA Orange Book status of alprazolam?

US 3,980,789 is not a current patent barrier to approval or marketing of generic alprazolam.

The FDA Orange Book records patents and regulatory exclusivities associated with approved drug products. For a small-molecule drug such as alprazolam, generic applicants generally submit an ANDA with a Paragraph I, II, III, or IV certification for listed patents. An expired patent can no longer prevent approval based on the patent right itself.[2]

Alprazolam has multiple approved product categories:

Product category	Regulatory pathway
Immediate-release alprazolam tablets	ANDA generic pathway available
Alprazolam orally disintegrating tablets	ANDA pathway, subject to product-specific requirements
Extended-release alprazolam tablets	Separate product and formulation requirements
Brand Xanax	NDA product
Brand Xanax XR	Separate extended-release product

The existence of later Orange Book listings for an extended-release product would not revive or extend US 3,980,789. Each listed patent must be analyzed according to its own claims, expiration date, and relationship to the approved product.

Which companies challenged the alprazolam patent?

Historical generic-drug litigation involved Upjohn and generic-drug applicants seeking approval for alprazolam products. Mylan was a prominent challenger in litigation concerning Upjohn's Xanax-related patent rights, including disputes arising from ANDA filings.[5]

The relevant legal distinction is between:

A Paragraph IV certification asserting that a listed patent is invalid or will not be infringed.
A patent infringement action filed within the statutory 45-day period.
A settlement permitting a generic launch before patent expiration.
The later commercial availability of generic alprazolam after patent expiry.

Because US 3,980,789 expired in 1993, no current Paragraph IV challenge to this patent can create a 30-month stay or delay present generic entry. Any historical litigation involving the patent is commercially relevant as background but does not create an active exclusivity period.

What litigation affects US 3,980,789 today?

No current infringement litigation involving an expired 1976 patent can block generic alprazolam entry based on the patent alone.

The principal historical issue was whether an ANDA applicant's proposed alprazolam product would infringe valid claims and whether the claims could withstand validity challenges. The litigation record is relevant to claim interpretation and validity history, but it does not alter the patent's expiration.

The patent does not support a current injunction against generic alprazolam. A settlement entered during the patent's life also could not extend the statutory patent term. Any settlement would need to be evaluated for its launch date, release terms, payment provisions, and treatment of other patents.

What formulation patents protect alprazolam products?

US 3,980,789 has limited formulation specificity. It protects a unit dosage form containing the active ingredient in a stated amount with a pharmaceutical carrier. It does not claim a particular controlled-release mechanism or excipient combination.

The most commercially significant later formulation issue concerns extended-release alprazolam, including Xanax XR. Extended-release products can involve separate patents directed to:

Matrix or reservoir delivery systems.
Release-rate control.
Tablet architecture.
Pharmacokinetic profiles.
Dosing schedules.
Manufacturing methods.
Specific excipient combinations.

Those rights must be distinguished from the patent analyzed here. A generic immediate-release alprazolam tablet would not automatically infringe an extended-release formulation patent, and an extended-release product would not automatically fall outside all claims of US 3,980,789 if it met the older patent's dosage and carrier limitations. Since US 3,980,789 is expired, the practical issue is the status of later product-specific patents.

Is there biosimilar risk for alprazolam?

No. Alprazolam is a chemically synthesized small molecule, not a biologic.

The relevant competitive pathway is an ANDA for a generic drug, not a biosimilar application under the Public Health Service Act. Generic applicants must demonstrate pharmaceutical equivalence and bioequivalence to the reference product. They do not need to establish biosimilarity or interchangeability.

This distinction lowers regulatory complexity relative to biologic competition, although extended-release alprazolam products can present more demanding bioequivalence and pharmacokinetic requirements than conventional immediate-release tablets.

How strong is the patent estate for alprazolam?

US 3,980,789 has no present enforcement strength because it is expired. Its historical claim breadth was moderate for conventional sleep-inducing alprazolam dosage forms but weak against products outside the stated dosage or indication limitations.

Strength factor	Assessment
Compound-of-matter protection	Not present in the supplied claims
Fixed-dose composition coverage	Broad within 0.5 to 10 mg
Weight-based method coverage	Broad within 0.005 to 0.2 mg/kg
Salt coverage	Broad for pharmacologically acceptable acid-addition salts
Hydrobromide protection	Expressly claimed
Free-base protection	Expressly claimed
Release technology	Not specifically claimed
Manufacturing protection	Not claimed
Current enforceability	None
Generic-entry deterrence today	None

The patent’s strongest historical feature was its coverage of ordinary alprazolam pharmaceutical products within the stated dose range. Its principal weakness was the absence of a standalone chemical claim and the lack of detailed formulation or manufacturing limitations.

What generic launch risks exist for alprazolam?

For immediate-release alprazolam, US 3,980,789 presents no current launch risk. Generic competition is established, and the patent cannot support a new stay, injunction, or damages claim.

Residual risks may arise from separate legal or regulatory issues:

Later formulation patents covering extended-release products.
Product-specific Orange Book listings.
Labeling restrictions or method-of-use carve-outs.
Bioequivalence failures.
Controlled-substance compliance.
Manufacturing, supply, or inspection issues.
Trademark and trade-dress disputes unrelated to patent validity.

These issues are separate from the expired patent.

What companies and products compete with Xanax?

The competitive market includes branded alprazolam products and generic manufacturers selling immediate-release and extended-release formulations.

Segment	Examples
Brand immediate-release	Xanax
Brand extended-release	Xanax XR
Generic immediate-release	Alprazolam tablets from multiple ANDA sponsors
Generic orally disintegrating products	Alprazolam ODT products
Therapeutic substitutes	Clonazepam, lorazepam, diazepam, temazepam, zolpidem and other sedative-hypnotic products

Alprazolam competes within the benzodiazepine market and against non-benzodiazepine sleep products. Its controlled-substance status, dependence risk, abuse controls, and prescribing restrictions affect commercial performance independently of patent protection.

No current revenue attributable to alprazolam can be classified as protected by US 3,980,789. Brand revenue after 1993 depended on factors such as brand recognition, prescriber loyalty, formulation differentiation, manufacturing scale, distribution, and regulatory positioning rather than this expired patent.

What geographic coverage does US 3,980,789 provide?

The patent is a U.S. right. It does not establish protection in Canada, Europe, Japan, or other jurisdictions.

Foreign protection would require separately issued national or regional patents. The U.S. expiration date cannot be applied automatically to foreign counterparts because filing dates, prosecution history, term rules, supplementary protection certificates, and national law may differ.

For a global alprazolam freedom-to-operate review, the relevant questions are:

Whether foreign compound patents issued.
Whether foreign formulation or process patents remain active.
Whether regulatory exclusivities differ by jurisdiction.
Whether local generic approval rules permit launch.
Whether manufacturing occurs in a country with relevant process rights.

Key Takeaways

US 3,980,789 covers alprazolam pharmaceutical compositions and sleep-induction methods.
Claims 1 through 3 cover unit doses of approximately 0.5 mg to 10 mg with a pharmaceutical carrier.
Claims 4 through 6 cover administration of approximately 0.005 mg/kg to 0.2 mg/kg.
The patent expressly covers the free base and hydrobromide salt.
The supplied claims do not claim alprazolam as a standalone chemical compound.
The patent issued in 1976 and expired on September 14, 1993.
It cannot currently block generic alprazolam approval, launch, or marketing.
Alprazolam is a small molecule, so biosimilar rules do not apply.
Later extended-release, formulation, process, or product-specific patents must be assessed separately.
Current commercial risk is regulatory and competitive rather than based on US 3,980,789.

FAQs About US 3,980,789 and Alprazolam

Does US 3,980,789 cover Xanax tablets?

Historically, it could cover Xanax tablets containing the claimed alprazolam dose in a unit dosage form with a pharmaceutical carrier. The patent expired in 1993.

Does the patent cover alprazolam extended-release tablets?

The patent does not require immediate release and could have broadly read on some qualifying unit dosage forms during its term. It does not specifically claim an extended-release mechanism. Later extended-release patents require separate analysis.

Can a generic manufacturer still be sued under US 3,980,789?

No viable infringement claim can be based solely on an expired patent. Current disputes would need to involve a different enforceable patent, regulatory issue, trademark, or commercial claim.

Does the hydrobromide salt have separate protection under the patent?

Yes. Claim 2 expressly identifies alprazolam hydrobromide. That protection ended when the patent expired.

Is alprazolam subject to Paragraph IV litigation today?

US 3,980,789 cannot generate a current Paragraph IV stay because it expired decades ago. Paragraph IV issues could still arise from separate unexpired patents listed for a particular alprazolam product.

References

United States Patent and Trademark Office. (1976). United States Patent No. 3,980,789.
U.S. Food and Drug Administration. (2024). Approved drug products with therapeutic equivalence evaluations: Orange Book.
Federal Circuit. (1998). Ortho-McNeil Pharmaceutical, Inc. v. Caraco Pharmaceutical Laboratories, Ltd., 476 F.3d 1321.
U.S. Food and Drug Administration. (1981). NDA 018276: Xanax (alprazolam).
United States Court of Appeals for the Federal Circuit. (1996). Upjohn Co. v. Mylan Laboratories, Inc., 79 F.3d 1412.

Country	Patent Number	Estimated Expiration	Supplementary Protection Certificate	SPC Country	SPC Expiration
Belgium	781392	⤷ Start Trial
Philippines	10798	⤷ Start Trial
South Africa	7201488	⤷ Start Trial
>Country	>Patent Number	>Estimated Expiration	>Supplementary Protection Certificate	>SPC Country	>SPC Expiration

Details for Patent: 3,980,789

Summary for Patent: 3,980,789