United States Patent 5,763,407: Desmopressin Claims, Scope, Expiration, and Patent Landscape

U.S. Patent No. 5,763,407 covers high-purity, large-batch desmopressin and selected therapeutic doses prepared from those batches. Its central technical limitation is an iodine-mediated final oxidation step performed on at least kilogram quantities of a protected or derivative desmopressin precursor. The patent does not provide a live U.S. barrier to generic desmopressin because its statutory term expired in 2015. Its historical claim scope was narrow and heavily dependent on batch size, purity, manufacturing conditions, and, for two claims, a product-by-process formulation.

What does U.S. Patent 5,763,407 cover?

The patent covers desmopressin, also known as DDAVP, used to treat diabetes insipidus, hemophilia A, and von Willebrand disease. Desmopressin is a synthetic vasopressin analog with the molecular formula C46H64N14O12S2.

The claims are directed to three related subject matters:

Claim	Claim category	Principal limitations
1	Treatment method combined with manufacturing limitations	Administration of desmopressin by oral, nasal, or intravenous route; therapeutic effect; batch of at least about 50 g; at least 98.5% desmopressin; final iodine oxidation step using at least about 1 kg of precursor
2	Oral dose prepared from a qualifying batch	Single oral dose; treatment of the three named diseases; source batch of at least about 500 g; at least 98.5% desmopressin; same kilogram-scale iodine oxidation step
3	Single oral dose with batch-origin limitations	Single oral dose; source batch containing at least 44 g desmopressin; no more than 1.5% adjoining matter other than water and acetic acid

The claims do not broadly cover every desmopressin product or every use of desmopressin. They require specific manufacturing history or batch characteristics.

What technical process does Patent 5,763,407 claim?

The claimed process is a final oxidative cyclization or disulfide-forming step. The process uses:

A mercaptopropionyl-containing desmopressin precursor, identified as SEQ ID NO: 2, or a derivative stable at neutral or slightly acidic pH.
A protic solvent.
Neutral or slightly acidic reaction conditions.
A separately prepared iodine solution.
Introduction of the iodine solution into the precursor solution under agitation.
A reaction solution in which desmopressin forms.
A scale of at least approximately 1 kg of precursor.

The process is materially different from a generic claim to “making desmopressin.” A manufacturer would need to satisfy the claimed scale, solvent, pH, iodine addition, agitation, precursor identity, and final-product specifications to fall within the literal scope of claims 1 or 2.

The wording “at least about 1 kg” creates a scale threshold. A process using substantially less precursor would have a strong noninfringement position under the literal claim language, although equivalence analysis could have been relevant while the patent was enforceable.

How should each claim be construed?

Claim 1: treatment method with a process limitation

Claim 1 combines a therapeutic method with manufacturing requirements. The accused party would need to be linked to:

Administration of desmopressin;
One of the claimed routes;
Treatment of one of the three named conditions;
A therapeutic dose;
A qualifying batch of at least about 50 g;
At least 98.5% desmopressin, measured against adjoining matter excluding water and acetic acid; and
The specified kilogram-scale iodine process.

This structure limits the claim substantially. A physician administering desmopressin may not know or control how the active ingredient was manufactured. A manufacturer that made a qualifying batch but did not administer the drug would not, by that conduct alone, practice the complete method claim. Liability theories would have depended on direct, induced, or contributory infringement and the facts surrounding distribution and labeling.

The phrase “effective to produce a physiological effect” is functional. It ties the claim to a pharmacologically active dose but does not state a fixed microgram amount. The relevant dose would vary by route, indication, formulation, and patient.

Claim 2: oral dose linked to a 500-gram batch

Claim 2 is narrower than claim 1 in route but broader in batch size. It requires an oral dose prepared from a batch of at least about 500 g, with the same 98.5% purity and final iodine process.

The claim does not cover nasal or intravenous dosing. It also does not merely claim an oral tablet or oral solution. The dose must be prepared from a qualifying batch. That source-batch limitation makes the claim difficult to assess from the finished dosage form alone unless manufacturing records, batch records, certificates of analysis, or discovery evidence establish the origin of the desmopressin.

Claim 3: oral dose with purity and batch-mass limitations

Claim 3 omits the express iodine-process requirement. It requires:

A single oral dose;
A therapeutic use for diabetes insipidus, hemophilia A, or von Willebrand disease;
Preparation from a single batch;
At least 44 g of desmopressin in that batch; and
No more than 1.5% total adjoining matter, excluding water and acetic acid.

Claim 3 is therefore the broadest of the three claims from a process perspective. It does not expressly require the particular precursor, iodine reagent, solvent, pH, agitation, or kilogram-scale reaction. Its practical scope still depends on proving the batch identity and the purity calculation.

What are the principal claim-construction issues?

“Adjoining matter”

“Adjoining matter” appears to refer to impurities or associated non-desmopressin material measured against the desmopressin content. The exclusion of water and acetic acid is significant because desmopressin is commonly handled as an acetate salt or in aqueous/acetic-acid-containing preparations.

The purity limitation should not automatically be read as a conventional assay specification for every finished dosage form. The claims describe batch composition, not necessarily the concentration of desmopressin in a tablet, spray, or injectable solution.

“Single batch”

The single-batch language is a traceability requirement. Blending material from multiple batches could create a noninfringement argument if the claim requires that the dose originate from one qualifying batch. The strength of that argument would depend on whether the claim is interpreted as requiring physical preparation from one batch or merely a batch meeting the stated composition.

Product-by-process language

Claims 2 and 3 describe a dose by reference to the process and batch from which it was prepared. U.S. patent law generally treats product-by-process claims as product claims for infringement purposes, while the process language can define the required product characteristics and may remain relevant to validity and claim scope. The Federal Circuit has addressed this distinction in cases including Abbott Laboratories v. Sandoz, Inc. and In re Thorpe.

For a generic manufacturer, the key question would have been whether the resulting desmopressin product was materially distinguishable from the patented product and whether the claim’s process language imposed a substantive limitation. The answer would have required analysis of the patent specification, prosecution history, and controlling precedent.

“About” and functional terms

The terms “about 50 g,” “about 500 g,” “about 1 kg,” and “effective to produce a physiological effect” introduce interpretive issues. The specification and prosecution history would control the permissible range. A process using 950 g rather than 1 kg, for example, could raise an “about” issue, but the patent does not establish a universal tolerance percentage.

When did U.S. Patent 5,763,407 lose exclusivity?

The patent’s ordinary 20-year U.S. patent term expired in 2015, measured from the relevant nonprovisional filing date under 35 U.S.C. § 154. The patent issued on June 9, 1998. It therefore no longer supplies an enforceable U.S. patent right against current desmopressin manufacturers.

Event	Date or status
U.S. patent grant	June 9, 1998
Patent term framework	20 years from applicable nonprovisional filing date
U.S. patent expiration	2015
Current enforceability	Expired
Current Paragraph IV risk from this patent	None
Current blocking effect on generic launch	None

Expiration eliminates infringement liability for activities occurring after expiration. It does not erase historical validity questions, prior litigation, damages exposure for the enforceable period, or the evidentiary value of the patent as a description of the manufacturing technology.

What was the Orange Book status of Patent 5,763,407?

Patent 5,763,407 is a process and dose-origin patent, not a conventional patent directed to a specific FDA-approved product label. Its claims do not identify a branded dosage form, NDA product, strength, or delivery system in the manner normally associated with Orange Book listing practice.

The patent should not be treated as a current Orange Book barrier to abbreviated new drug application approval. Orange Book relevance depends on whether a patent was submitted for a specific NDA product and accepted for listing by FDA. The presence of a patent in the U.S. patent database does not establish Orange Book listing status. FDA’s Approved Drug Products with Therapeutic Equivalence Evaluations is the controlling source for listed patents and exclusivity information for approved small-molecule products. [2]

Did Patent 5,763,407 create a Paragraph IV obstacle?

Historically, a Paragraph IV certification could have been relevant if the patent had been listed against an applicable desmopressin NDA and the ANDA product fell within the listed claims. The patent’s manufacturing and batch-origin limitations would have created a fact-intensive certification issue.

A generic applicant could have argued that:

Its process did not use the specified precursor;
It did not perform the iodine addition under the claimed conditions;
Its reaction scale was below the claimed threshold;
Its desmopressin was not made in a single qualifying batch;
Its product did not meet the claimed purity or batch-mass limits;
Its label did not induce treatment of every claimed indication; or
The claims were invalid for lack of enablement, written description, anticipation, obviousness, or indefiniteness.

Because the patent expired in 2015, it cannot support a new Paragraph IV challenge or a current 30-month stay under the Hatch-Waxman framework.

What FDA products and dosage forms compete with desmopressin?

Desmopressin has been marketed in several delivery systems:

Dosage form	Typical product category	Commercial and regulatory relevance
Oral tablet	DDAVP and generic desmopressin tablets	Generic competition is established
Nasal spray	Desmopressin nasal formulations, including DDAVP-type products	Route-specific formulation and device issues may apply
Injection	Intravenous or subcutaneous products	Used where controlled parenteral dosing is required
Sublingual tablet	Nocdurna and related products	Newer delivery system with distinct formulation and regulatory issues
Hemostatic nasal product	Stimate-type desmopressin	Product-specific manufacturing and supply issues

FDA approval of a desmopressin product does not imply freedom to practice every patent covering a formulation, device, manufacturing process, indication, or dosing regimen. Patent 5,763,407, however, is no longer an enforceable U.S. constraint.

What patents protect newer desmopressin formulations?

Later patent estates may focus on formulation and delivery rather than bulk synthesis. Relevant categories include:

Sublingual and orally disintegrating formulations

These patents can claim:

Low-dose desmopressin compositions;
Sublingual or buccal delivery;
Rapid disintegration;
Water-soluble excipient systems;
Reduced fluid-intake regimens;
Dosing schedules designed to reduce hyponatremia risk.

Nocdurna’s regulatory profile is distinct from older oral tablets because the product uses a low-dose sublingual route and has specific fluid-restriction labeling. FDA labeling and Orange Book records must be reviewed separately from the expired bulk-process patent. [2, 3]

Nasal spray and device patents

Nasal products may raise patent issues involving:

Spray-pump geometry;
Metered-dose delivery;
Droplet-size distribution;
Formulation viscosity and pH;
Preservative systems;
Container-closure compatibility.

These rights generally do not depend on the large-batch iodine oxidation process claimed in Patent 5,763,407.

Method-of-use patents

Later patents or regulatory exclusivities may address:

Nocturnal enuresis;
Nocturia;
Mild hemophilia A;
von Willebrand disease;
Central diabetes insipidus;
Age-specific dosing;
Fluid-management protocols.

A method-of-use patent can remain commercially relevant even when the active ingredient and basic tablet are off patent. Its practical effect depends on whether the generic label carves out the patented indication and whether the remaining label still encourages infringement.

How strong was the patent estate for desmopressin?

The estate represented by Patent 5,763,407 was technically narrow but commercially relevant during its term.

Factor	Assessment
Active ingredient coverage	Weak; the claims do not broadly cover all desmopressin
Bulk manufacturing coverage	Moderate if the accused process matched the iodine and scale limitations
Formulation coverage	Limited; no detailed tablet, spray, device, or excipient claims appear in the supplied claims
Method-of-use coverage	Present but tied to manufacturing and batch limitations
Proof burden	High because batch origin and manufacturing conditions must be established
Current enforceability	None because the patent expired
Generic launch significance today	No blocking significance

The patent’s principal commercial value was process control and manufacturing standardization, not control of the desmopressin molecule itself.

What generic entry risks exist for desmopressin?

Current generic entry risk is determined primarily by other rights and regulatory requirements:

Product-specific Orange Book patents for branded formulations;
Formulation patents for sublingual or nasal products;
Device patents for metered nasal delivery;
Method-of-use patents;
FDA requirements for bioequivalence and route-specific clinical performance;
Manufacturing validation and impurity-control requirements;
Supply continuity for sterile injectable and nasal products;
Potential post-marketing safety requirements relating to hyponatremia.

Patent 5,763,407 does not create current generic-entry risk. A generic manufacturer using a different synthesis route does not need to design around this expired patent for U.S. launch purposes.

What litigation or settlement agreements affect Patent 5,763,407?

No current litigation or settlement agreement can extend the patent’s expired U.S. term. Any historical enforcement or settlement involving the patent would have been limited to the period before expiration and would not restore exclusivity.

A complete historical litigation chronology cannot be established from the claims alone. The patent record establishes the claim text and legal status, but litigation databases, district-court dockets, Federal Circuit opinions, and settlement filings are required to attribute specific cases, defendants, dates, or license terms accurately.

What licensing and manufacturing barriers remain after expiration?

Patent expiration removes the U.S. patent barrier but does not eliminate:

Trade-secret protection for process optimization;
Know-how relating to iodine addition and reaction control;
Scale-up data;
Impurity profiling;
Batch-release specifications;
Supplier qualification;
Sterile manufacturing controls;
Regulatory documentation;
Foreign patent rights with later expiration dates.

Geographic coverage must be assessed jurisdiction by jurisdiction. U.S. expiration does not establish expiration of corresponding European, Canadian, Japanese, or other national family members. A manufacturer exporting from a jurisdiction where a corresponding patent remains active could face separate infringement exposure.

Key Takeaways

U.S. Patent 5,763,407 claims high-purity desmopressin made in large batches using a specified iodine-mediated final synthetic step.
Claim 1 covers treatment by oral, nasal, or intravenous administration but requires a qualifying manufacturing process and batch.
Claim 2 is limited to an oral dose from a batch of at least about 500 g and includes the same process limitations.
Claim 3 omits the express iodine-process limitation but requires a single oral dose prepared from a qualifying 44-gram batch.
The patent expired in 2015 and creates no current U.S. infringement or Paragraph IV barrier.
Later desmopressin risks are more likely to involve formulation, device, sublingual delivery, dosing regimen, method-of-use, and manufacturing know-how rights.
Orange Book status must be assessed by NDA product and listed patent, not by the existence of the expired patent in the USPTO database.
Foreign counterparts may have had different expiration dates and legal outcomes.

Frequently Asked Questions

Is U.S. Patent 5,763,407 a patent on desmopressin itself?

No. The supplied claims do not broadly claim the desmopressin molecule. They claim therapeutic doses and treatment methods tied to specific batch characteristics and, in claims 1 and 2, a defined manufacturing step.

Can a generic manufacturer use the iodine oxidation process today?

In the United States, the patent no longer prevents use of the claimed process because Patent 5,763,407 expired in 2015. Separate trade-secret, contractual, foreign-patent, or regulatory restrictions may still apply.

Does the patent cover desmopressin acetate tablets?

Not categorically. The claims refer to desmopressin purity while excluding water and acetic acid from the adjoining-matter calculation. They do not recite a complete tablet composition, excipient system, strength, dissolution profile, or tablet manufacturing process.

Does Patent 5,763,407 cover desmopressin nasal spray?

Claim 1 recites nasal administration, but only as part of a treatment method that also requires the claimed batch and manufacturing characteristics. It is not a standalone nasal-spray formulation claim.

Can the expired patent still affect an FDA approval?

It can remain relevant as historical prior art or as part of technical background, but it cannot support a current patent-based FDA stay or block U.S. approval after expiration.

References

United States Patent and Trademark Office. (1998). U.S. Patent No. 5,763,407, Desmopressin-related manufacturing and dosage claims.
U.S. Food and Drug Administration. (2024). Approved drug products with therapeutic equivalence evaluations (Orange Book).
U.S. Food and Drug Administration. (2020). Nocdurna (desmopressin acetate) prescribing information.
35 U.S.C. § 154. Patent term.
Abbott Laboratories v. Sandoz, Inc., 566 F.3d 1282 (Fed. Cir. 2009).
In re Thorpe, 777 F.2d 695 (Fed. Cir. 1985).
Nautilus, Inc. v. Biosig Instruments, Inc., 572 U.S. 898 (2014).

Country	Patent Number	Estimated Expiration	Supplementary Protection Certificate	SPC Country	SPC Expiration
Austria	193892	⤷ Start Trial
Germany	69424940	⤷ Start Trial
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European Patent Office	0710243	⤷ Start Trial
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Greece	3034405	⤷ Start Trial
Mexico	9710103	⤷ Start Trial
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Details for Patent: 5,763,407

Summary for Patent: 5,763,407